WO2018128156A1 - Polyurethane film and method for manufacturing same - Google Patents

Abstract

The purpose of the present invention is to provide: a polyurethane film in which the delamination of a polyurethane layer that occurs when the polyurethane film is used in cold climates is alleviated; and a method for manufacturing the polyurethane film. This polyurethane film contains polyurethane and silicon atoms, and is characterized by satisfying equation (1) below. (1) 1<A/B≤100, where A is the content of silicon atoms on the surface of the polyurethane film, and B is the content of silicon atoms on the back surface of the polyurethane film.

Description

Polyurethane film and method for producing the same

The present invention relates to a polyurethane film and a method for producing the same, and more particularly to a polyurethane film and the like in which peeling of a polyurethane layer is improved in use in a cold region.

In recent years, a polyurethane film has been used as a paint protection film (PPF) in order to protect the exterior paint of automobiles from scratches caused by car washing or running pebbles.

Since polyurethane has a high elastic modulus, it can respond reversibly to some dents and scratches, and it is accepted in the market as self-healing. It is known that the polyurethane film is usually formed from two or more polyurethane layers of a protective layer having a high self-healing property and a base material layer supporting the same from the viewpoint of self-healing property (for example, patents) Reference 1).

However, since the polyurethane film is disposed on the exterior paint of an automobile, it is necessary to clear a very strict standard. However, when the inventor evaluated the polyurethane film described in Patent Document 1, In an actual vehicle test in a low temperature environment of about 20 ° C., peeling of the polyurethane film from the base material layer was observed.

Therefore, there is a high demand for a polyurethane film having improved peelability between the base material layer and the protective layer, which are constituent layers, even in a low temperature environment when used in cold regions.

Special table 2008-539107 gazette

The present invention has been made in view of the above-mentioned problems and situations, and a problem to be solved is to provide a polyurethane film in which peeling of a polyurethane layer is improved in a cold district and a method for producing the same.

In order to solve the above-mentioned problems, the present inventor is a polyurethane film containing polyurethane and silicon atoms in the process of examining the cause of the above-mentioned problem, and the silicon atom content A on the surface of the polyurethane film, It has been found that the polyurethane film satisfying a specific relationship with the silicon atom content B on the back surface of the polyurethane film improves the peeling of the polyurethane layer in use in a cold region, and has led to the present invention.

That is, the above-mentioned problem according to the present invention is solved by the following means.

1. A polyurethane film containing polyurethane and silicon atoms,
A polyurethane film characterized in that the silicon atom content A on the surface of the polyurethane film and the silicon atom content B on the back surface of the polyurethane film satisfy the following formula (1).

Formula (1) 1 <A / B ≦ 100
2. 2. The polyurethane film according to item 1, wherein the silicon atom is introduced from a silane coupling agent or a polysiloxane derivative.

3. 2. The polyurethane film according to item 1, wherein the silicon atom content A on the surface of the polyurethane film and the silicon atom content C inside the polyurethane film satisfy the following formula (2).

Formula (2) 1 <C / A
4). The polyurethane film according to any one of items 1 to 3, wherein the polyurethane film has a laminated structure, and the laminated structure is composed of at least a base material layer and a protective layer.

5). A method for producing a polyurethane film for producing the polyurethane film according to any one of items 1 to 4,
A method for producing a polyurethane film comprising a step of laminating a plurality of layers containing polyurethane, wherein at least one of the plurality of layers contains silicon atoms.

6. The step of laminating a plurality of layers containing polyurethane comprises a protective layer containing polyurethane and a silane coupling agent or a polysiloxane derivative applied on the release surface of the separator, and a base material layer containing at least polyurethane. 6. The method for producing a polyurethane film according to item 5, which is a step of pasting together while pressing with a nip roller.

By the above means of the present invention, it is possible to provide a polyurethane film in which the peeling of the polyurethane layer is improved in a cold region and a method for producing the same.

The expression mechanism or action mechanism of the effect of the present invention is not clear, but is presumed as follows.

As a result of earnestly examining the means for improving the peeling of the constituent layers of the polyurethane film, the present inventor is a polyurethane film containing polyurethane and silicon atoms, the silicon atom content A on the surface of the polyurethane film, and the polyurethane It has been found that the silicon atom content B on the back surface of the film can be improved by satisfying the formula (1), and the present invention has been achieved.

The mechanism of the present invention is estimated as follows.

Polyurethane film is affixed to the vehicle body in a stretched state because of its high elastic modulus derived from polyurethane. Therefore, considerable stress is accumulated in the film, and it is presumed that the film is concentrated particularly at the interface of the layers. In normal temperatures and warm environments, polyurethane is flexible, so stress is easily dispersed and no delamination occurs. However, in a low temperature environment of about −20 ° C., the polyurethane becomes hard and stress is likely to be concentrated locally. In particular, the layer interface is broken, that is, peeled off at a portion having a high curvature such as the end of an automobile frame. It is considered a thing.

The effect of the present invention is that the binding energy of the layer interface between the base material layer and the protective layer of the polyurethane film is increased by “siloxane bond” (—Si—O—Si—) derived from a silane coupling agent or a polysiloxane derivative. Thus, it is presumed that delamination has become difficult.

That is, by providing a slope of the silicon atom content A on the surface side with the protective layer of the polyurethane film and the silicon atom content B on the back surface with the base material layer of the polyurethane film as in the formula (1), It is presumed that the silicon atom content in the protective layer was increased and the siloxane bond at the layer interface between the base material layer and the protective layer was strengthened to improve the peel resistance in a low temperature environment.

Furthermore, the polyurethane film of the present invention forms a protective layer containing polyurethane and a silane coupling agent or a polysiloxane derivative on the release surface of the separator, and the separator and the base material layer are bonded together by a nip roller. In the case of an embodiment in which a laminated structure is formed, the surface of the protective layer having a high silicon atom content is arranged inside the film, so that the siloxane bond at the layer interface is further strengthened, and higher peel resistance can be realized in a low temperature environment. (Equation (2)).

This is presumed that the silicon atom-containing compound is moved to the surface side of the protective layer as the solvent evaporates when the coating film is dried. Especially in the case of a silane coupling agent, the molecular weight is lower and the surface tension is lower. There is also an influence of the coupling group, and it is thought that the tendency becomes stronger. Therefore, it is presumed that a part having a large silicon atom content is present inside the polyurethane film by bonding the surface of the protective layer having a large silicon atom content and the base material layer together.

From the above, the adhesion between the layers is sufficient due to the intermolecular force between polyurethanes and urethane bonds under normal temperature environment, but it is necessary to further increase the bond density in low temperature environments such as the present invention. Suggests.

The schematic diagram which shows an example of the preferable structure of the polyurethane film of this invention Schematic which shows an example of the preferable manufacturing method of the polyurethane film of this invention.

The polyurethane film of the present invention is a polyurethane film containing polyurethane and silicon atoms, and the silicon atom content A on the surface of the polyurethane film and the silicon atom content B on the back surface of the polyurethane film are expressed by the following formula (1). ) Is satisfied.

Formula (1) 1 <A / B ≦ 100
This feature is a technical feature common to or corresponding to the claimed invention.

As an embodiment of the present invention, from the viewpoint of manifestation of the effect of the present invention, the introduction of the silicon atom from a silane coupling agent or a polysiloxane derivative has a low haze and transparency in addition to the effect of the present invention. From the viewpoint of obtaining a high film.

The use of a siloxane bond in the base material layer and the protective layer in cold districts means that the silicon atom content A on the surface of the polyurethane film and the silicon atom content C inside the polyurethane film satisfy the above formula (2). It is possible to further improve the adhesion at the interface and further improve the peeling at the layer interface.

In addition, the polyurethane film has a laminated structure, and that the laminated structure is composed of at least a base material layer and a protective layer has a high elastic modulus as a polyurethane film to be bonded to a vehicle body, and is in a tensile state. This is a preferred embodiment as a protection film that is durable and has an excellent protective function for car body painting.

The method for producing a polyurethane film for producing a polyurethane film of the present invention is characterized in that in the step of laminating a plurality of layers containing the polyurethane, at least one of the plurality of layers contains silicon atoms.

Furthermore, the step of laminating a plurality of layers containing polyurethane comprises a protective layer containing polyurethane and a silane coupling agent or a polysiloxane derivative coated on the release surface of the separator, and a substrate containing at least polyurethane It is a preferable method for producing a polyurethane film from the viewpoint of achieving both the effect of further improving the peel resistance according to the present invention and the productivity, in which the layer is bonded to the layer while being pressed with a nip roller.

Hereinafter, the present invention, its components, and modes and modes for carrying out the present invention will be described in detail. In the present application, “˜” is used to mean that the numerical values described before and after it are included as a lower limit value and an upper limit value.

<< Outline of polyurethane film of the present invention >>
The polyurethane film of the present invention is a polyurethane film containing polyurethane and silicon atoms, and the silicon atom content A on the surface of the polyurethane film and the silicon atom content B on the back surface of the polyurethane film are expressed by the following formula (1). This structure provides a polyurethane film in which the peeling of the polyurethane layer in a low temperature environment such as a cold region is improved, and a method for producing the polyurethane film. Moreover, it is preferable that the polyurethane film of this invention has a laminated structure, and the said laminated structure is comprised at least by a base material layer and a protective layer.

Formula (1) 1 <A / B ≦ 100
When the range of the formula (1) is preferably 5 ≦ A / B ≦ 50, in addition to the effect of improving the peel resistance of the present invention, a polyurethane film having low haze and high transparency is easily obtained.

Here, the “front surface” refers to a portion from the interface between the polyurethane film surface and air to a thickness of 1 μm in the film thickness direction, and refers to a portion in which silicon atoms according to the present invention are contained more than the following “back surface”.

The “back surface” means a portion located on the opposite surface of the “front surface” of the polyurethane film, and refers to a portion from the interface with air or another medium up to 1 μm in the film thickness direction. Depending on the application, it may come into contact with another base film or adhesive.

When the polyurethane film has a laminated structure of a base material layer and a protective layer, the silicon atom content A is the surface on the protective layer side, and the silicon atom content B is a protective layer of the base material layer. The silicon atom content on the surface opposite to the surface, that is, the back surface is preferable.

The “inside” means a film portion of the polyurethane film that is neither the “front surface” nor the “back surface”.

The value of the silicon surface content ratio between the “surface” and the “inside” preferably satisfies the formula (1) and the formula (2) in order to further improve the adhesion between the base material layer and the protective layer. In addition to the effects of the present invention, the range of 1.5 ≦ C / A ≦ 2.5 is preferable from the viewpoint of obtaining a film with low haze and high transparency of the polyurethane film.

The “protective layer” according to the present invention is a layer including a part of the “surface” and the “inside” in the polyurethane film, and in the present invention, the thickness is preferably about 2 to 50 μm. .

The “base material layer” according to the present invention is a layer including the “back surface” and the “inside” in a polyurethane film, and preferably has a thickness of about 2 to 200 μm.

“Separator” is generally called a release film, and refers to a film having at least a base material and an adhesive layer, and the base material having peelability. In the present invention, the “protective layer” according to the present invention may be formed on the release surface of the separator.

“Silicon atom content” is determined by using an EDX (Energy-dispersive X-ray Spectroscopy) while observing the cross section of the polyurethane film with an SEM (scanning electron microscope). Can be measured. The silicon atom content is calculated based on the following formula. Ten points of the “front surface” and the “back surface” of the sample are measured at random, and the average value is used. That is, the average value of the silicon atom content in the region from the “front surface” or “back surface” to 1 μm in the film thickness direction is determined.

Internal silicon atom content is measured at 10 points on the silicon atom content at random by the EDX mapping function when there is a silicon atom content in the “inside” of the film. The average value is used.

The silicon atom content obtained by the following formula is not the silicon atom content itself, but is a value capable of relatively comparing the silicon surface content of “front surface” and “back surface” or “inside”.

Silicon atom content = (X-ray count at 1.74 keV at EDX (cps)) / (X-ray count at 1.60 keV at EDX (cps))
As an example of an apparatus that can be used, JSM-6060LA (manufactured by JEOL Ltd.) can be used for the SEM, and Apollo 40 (manufactured by Ametech Co., Ltd.) can be used for EDX.

<Configuration of polyurethane film of the present invention>
FIG. 1 is a schematic view showing an example of a preferred configuration of the polyurethane film of the present invention.

The polyurethane film 1 of the present invention preferably has a layer structure of at least a base material layer 2 and a protective layer 3. The base material layer 2 may be a film containing polyurethane as a main component or a film containing polyurethane and a silane coupling agent or a polysiloxane derivative as main components.

The protective layer 3 is preferably a layer containing polyurethane and a silane coupling agent or a polysiloxane derivative as main components. The “main component” means a component mainly containing 50% by mass or more of the solid content including the resin contained in the base material layer or the protective layer, preferably 70% by mass or more, more preferably 80% by mass. % Or more, particularly preferably 90% by mass or more.

The base material layer 2 and the protective layer 3 can each constitute a polyurethane film of the present invention by laminating a plurality of layers. For example, by laminating a plurality of protective layers 3 having different contents of silane coupling agent or polysiloxane derivative on the base material layer 2, an arbitrary inclination is provided to the “surface” and “inner” silicon atom contents. It is possible. Here, “gradient” refers to a form in which there is a concentration gradient of silicon atom content along the thickness direction of the film.

Further, the protective layer 3 may be directly laminated on the base material layer 2, but at least a polyurethane containing a polyurethane and a silane coupling agent or a polysiloxane derivative coated on the release surface of the separator. In some cases, a polyurethane film that is a laminate is formed by performing a bonding process (hereinafter also referred to as a laminating process) by heating or pressurizing the base material layer containing s. Even in this case, the base layer can contain a silane coupling agent or a polysiloxane derivative together with polyurethane.

A well-known anchor coat layer may be provided on the surface of the base material layer as an intermediate layer for improving the smoothness of the base material layer 2 and the adhesion of the protective layer 3 to the base material layer 2.

In addition, on the back surface of the base material layer 2, when the base material layer 2 is heated, low molecular weight components such as monomers and oligomers are deposited from the inside to the surface, and a bleed out preventing layer for the purpose of suppressing so-called bleed out. May be provided.

[1] Polyurethane The polyurethane according to the present invention is a reaction product of one or more polyol components and one or more diisocyanate components. The one or more polyol components are preferably selected from polyester polyols, polycarbonate polyols, polyether polyols, polycaprolactone polyols, and the like to form a thermoplastic polyurethane. In the present invention, the thermoplastic polyurethane or a combination or blend thereof is preferable. Among these, these thermoplastic polyurethanes are preferably contained in the base material layer, and it is preferable to use polycarbonate polyol for the base material layer.

The one or more diisocyanate components are preferably a mixture of one or more diisocyanates and one or more triisocyanates. The triisocyanate component used with the diisocyanate is preferably about 10% by weight or less based on the total weight of the reaction constituents.

[1.1] Polyol Component [1.1.1] Polyester Polyol The polyester polyol used in the present invention usually has two or more ester bonds and two or more hydroxy groups in the molecule.

Examples of the polyester polyol include a polyester polyol obtained by a condensation reaction between a polyhydric alcohol and a polybasic acid. Here, as the polyhydric alcohol, ethylene glycol, 1,2-propanediol, 1,3-butanediol, 1,4-butanediol, 3-methyl-1,5-pentanediol, 1,6-hexane Diol, 3,3'-dimethylol heptane, 1,4-cyclohexanedimethanol, neopentyl glycol, 3,3-bis (hydroxymethyl) heptane, diethylene glycol, dipropylene glycol, glycerin, trimethylolpropane, etc. These may be used alone or in combination of two or more. Examples of the polybasic acid include succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, cyclopentanedicarboxylic acid, cyclohexanedicarboxylic acid, orthophthalic acid, isophthalic acid, terephthalic acid, and naphthalenedicarboxylic acid. These may be used alone or in combination of two or more.

Specific examples include polyester polyols such as polyethylene adipate diol, polybutylene adipate diol, and polyethylene succinate diol.

In the polyester polyol, the number average molecular weight (Mn) is preferably 400 to 2000, more preferably 500 to 1500, and most preferably 600 to 1200. The number average molecular weight (Mn) can be measured by general gel permeation chromatography (GPC).

These polyester polyols are available as reagents or industrially, and examples of commercially available polyester polyols include “Polylite (registered trademark)” series manufactured by DIC Corporation, and “Nipporan (registered trademark)” manufactured by Tosoh Corporation. Series, “Maximol (registered trademark)” series manufactured by Kawasaki Kasei Kogyo Co., Ltd., and the like.

[1.1.2] Polycarbonate polyol The polycarbonate polyol used in the present invention is preferably a polycarbonate diol, more preferably a polycarbonate diol having an alkylene group in which a plurality of methylene groups are linked. Hereinafter, the polycarbonate diol is referred to as “alkylene group-containing polycarbonate diol”. The hydroxy group value of the alkylene group-containing polycarbonate diol is preferably 100 to 250 mgKOH / g.

The alkylene group-containing polycarbonate diol is a polycarbonate diol having two hydroxy groups in its molecule, and can be obtained, for example, by a reaction between a diol compound and ethylene carbonate. Examples of the diol compound include 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 2-methyl-1,3-propanediol, 3-methyl-1, Examples thereof include linear or branched alkanediols such as 5-pentanediol, 2-ethyl-1,6-hexanediol, and 2,4-dimethyl-1,5-pentanediol. Moreover, the diol compound which contains an alicyclic structure, an aromatic ring structure, and both in the skeleton with these alkylene groups may be sufficient. The diol compound-derived part in the urethane part of the copolymer may be any one of the above diol compounds, or two or more of them may be used in combination.

[1.1.3] Polyether Polyol The polyether polyol used in the present invention is usually a hydroxy compound having one or more ether bonds in the main skeleton in the molecule. The repeating unit in the main skeleton may be either saturated hydrocarbon or unsaturated hydrocarbon, and may be linear, branched or cyclic.

Examples of the repeating unit include 1,2-ethylene glycol unit, 1,2-propylene glycol unit, 1,3-propanediol (trimethylene glycol) unit, 2-methyl-1,3-propanediol unit, 2 , 2-Dimethyl-1,3-propanediol unit, 1,4-butanediol (tetramethylone glycol) unit, 2-methyl-1,4-butanediol unit, 3-methyl-1,4-butanediol unit 3-methyl-1,5-pentanediol unit, neopentyl glycol unit, 1,6-hexanediol unit, 1,7-heptanediol unit, 1,8-octanediol unit, 1,9-nonanediol unit, Examples include 1,10-decanediol unit and 1,4-cyclohexanedimethanol unit.

Among the polyether polyols having these repeating units in the main skeleton, polytetramethylene ether glycol, polytrimethylene ether glycol, copolymer polyether polyol obtained by reaction of 1 to 20 mol% of 3-methyltetrahydrofuran and tetrahydrofuran (For example, “PTG-L1000”, “PTG-L2000” and “PTG-L3500” manufactured by Hodogaya Chemical Co., Ltd.) and copolymerized polyether glycols obtained by the reaction of neopentyl glycol and tetrahydrofuran are preferred.

These polyether polyols may be used alone or in combination of two or more, and may be variously selected according to the desired properties of the polyurethane.

The molecular weight of the polyether polyol used in the present invention is preferably a number average molecular weight (Mn) of 500 or more, more preferably 1000 or more, and further preferably 1500 or more. Further, it is preferably 5000 or less, more preferably 4000 or less, and further preferably 3500 or less.

[1.1.4] Polycaprolactone polyol A polyol having a lactone in the molecule can be produced by ring-opening polymerization of the following lactones, and by changing the amount of lactone used relative to the polyol, The content ratio can be easily changed.

Examples of the lactone include ε-caprolactone, 4-methylcaprolactone, 3,5,5-trimethylcaprolactone, 3,3,5-trimethylcaprolactone, β-propiolactone, γ-butyrolactone, δ-valerolactone, γ- Examples include valerolactone and enanthlactone. These may be used alone or in combination of two or more. Ε-caprolactone is most preferred because it is readily available and highly reactive.

[1.2] Diisocyanate Component In the present invention, an aliphatic diisocyanate compound, an alicyclic diisocyanate compound, an aromatic diisocyanate compound, and a mixture thereof are used as the diisocyanate component. Among these, it is preferable to use an aliphatic diisocyanate compound and / or an alicyclic diisocyanate compound from the viewpoint of weather resistance. For the same reason, 30 to 100% by mass, particularly 50 to 100% by mass of the diisocyanate compound is preferably an aliphatic diisocyanate compound.

If the diisocyanate compound which can be used conveniently for this invention is illustrated,
Aliphatic diisocyanate compounds such as tetramethylene-1,4-diisocyanate, hexamethylene-1,6-diisocyanate, octamethylene-1,8-diisocyanate, 2,2,4-trimethylhexane-1,6-diisocyanate;
Cyclobutane-1,3-diisocyanate, cyclohexane-1,3-diisocyanate, cyclohexane-1,4-diisocyanate, 2,4-methylcyclohexyl diisocyanate, 2,6-methylcyclohexyl diisocyanate, isophorone diisocyanate, norbornene diisocyanate, 4,4 ' Isomer mixtures of methylenebis (cyclohexyl isocyanate), hexahydrotoluene-2,4-diisocyanate, hexahydrotoluene-2,6-diisocyanate, hexahydrophenylene-1,3-diisocyanate, hexahydrophenylene-1,4-diisocyanate 1,9-diisocyanato-5-methylnonane, 1,1-bis (isocyanatomethyl) cyclohexane, 2-isocyanato-4-[(4-iso Anat cyclohexyl) methyl] -1-methyl-cyclohexane, 2- (3-isocyanatopropyl) cyclohexyl isocyanate, alicyclic diisocyanate compounds such as norbornane diisocyanate;
Phenylcyclohexylmethane diisocyanate, isomer mixture of 4,4'-methylenebis (phenylisocyanate), toluene-2,3-diisocyanate, toluene-2,4-diisocyanate, toluene-2,6-diisocyanate, phenylene-1,3- Diisocyanate, phenylene-1,4-diisocyanate, 1,3-bis (isocyanatomethyl) benzene, xylylene diisocyanate, tetramethylxylylene diisocyanate, naphthalene diisocyanate, diphenyl ether diisocyanate, 1,3-diisocyanatomethylbenzene, 4, 4'-diisocyanato-3,3'-dimethoxy (1,1'-biphenyl), 4,4'-diisocyanato-3,3'-dimethylbiphenyl, 1,2-diisocyanatobenzene 1,4-bis (isocyanatomethyl) -2,3,5,6-tetrachlorobenzene, 2-dodecyl-1,3-diisocyanatobenzene, 1-isocyanato-4-[(2-isocyanatocyclohexyl) methyl Aromatic diisocyanates such as 2-methylbenzene, 1-isocyanato-3-[(4-isocyanatophenyl) methyl) -2-methylbenzene, 4-[(2-isocyanatophenyl) oxy] phenyl isocyanate, diphenylmethane diisocyanate A compound etc. can be mentioned.

Among these, from the viewpoint of good adhesive strength, heat resistance, and coatability, as described above, 30 to 100% by mass, particularly 50 to 100% by mass of the diisocyanate compound is an aliphatic diisocyanate compound and an alicyclic compound. It is preferably at least one diisocyanate compound selected from the group consisting of diisocyanate compounds. Specific examples of suitable compounds include tetramethylene-1,4-diisocyanate, hexamethylene-1,6-diisocyanate, octamethylene-1,8-diisocyanate, 2,2,4-trimethylhexane-1,6- Diisocyanate, cyclobutane-1,3-diisocyanate, cyclohexane-1,3-diisocyanate, cyclohexane-1,4-diisocyanate, 2,4-methylcyclohexyl diisocyanate, 2,6-methylcyclohexyl diisocyanate, isophorone diisocyanate, norbornane diisocyanate, 4, Isomeric mixture of 4'-methylenebis (cyclohexyl isocyanate), hexahydrotoluene-2,4-diisocyanate, hexahydrotoluene-2,6-diisocyanate, hexahi Rofeniren 1,3 diisocyanate are hexahydrophthalate phenylene-1,4-diisocyanate. These isocyanate compounds may be used alone or in combination of two or more.

Further, a part of the NCO group of the diisocyanate compound may be modified to urethane, urea, burette, allophanate, carbodiimide, oxazolidone, amide, imide, etc., and the polynuclear substance contains isomers other than the above. The thing which is doing is also included.

These diisocyanate compounds are preferably used in an amount of usually 0.1 to 5 equivalents based on the total of the hydroxyl groups of the polyol and 1 equivalent of the total of the hydroxyl groups and / or amino groups of the chain extenders described below. 0.8 to 2 equivalents, more preferably 0.9 to 1.5 equivalents, most preferably 0.95 to 1.2 equivalents, and 0.98 to 1. 1 equivalent is particularly preferred.

When the amount of the diisocyanate compound is 5 equivalents or less, unreacted isocyanate groups are prevented from causing an undesirable reaction, and desired physical properties are easily obtained. Moreover, by setting it as 0.1 equivalent or more, the molecular weight of a polyurethane and a polyurethane urea can be made large enough, and it will become easy to express desired performance.

[1.3] Chain extender The chain extender used in the production of the polyurethane of the present invention is mainly classified into a compound having two or more hydroxy groups, a compound having two or more amino groups, and water. . Among these, a polyurethane having a short-chain polyol, specifically, a compound having a compound having two or more hydroxy groups is preferable. For the production of polyurethane urea, polyamine compounds, specifically, compounds having two or more amino groups are preferred.

These chain extenders may be used alone or in combination of two or more.

Examples of the compound having two or more hydroxy groups include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, 1,3-propanediol, 2-methyl-1,3- Propanediol, 2-methyl-2-propyl-1,3-propanediol, 2-butyl-2-ethyl-1,3-propanediol, 2-butyl-2-hexyl-1,3-propanediol, 1, 2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,5-pentanediol, 2-methyl-2,4-pentanediol, 3-methyl-1, 5-pentanediol, 2,2,4-trimethyl-1,3-pentanediol, ne Pentyl glycol, 1,6-hexanediol, 2-ethyl-1,3-hexanediol, 2,5-dimethyl-2,5-hexanediol, 1,8-octanediol, 2-methyl-1,8-octane Examples thereof include aliphatic glycols such as diol and 1,9-nonanediol, alicyclic glycols such as bishydroxymethylcyclohexane, and glycols having an aromatic ring such as xylylene glycol and bishydroxyethoxybenzene.

Examples of the compound having two or more amino groups include aromatic diamines such as 2,4- or 2,6-tolylenediamine, xylylenediamine and 4,4′-diphenylmethanediamine, ethylenediamine, 2-propylenediamine, 2,2-dimethyl-1,3-propanediamine, 1,3-pentanediamine, 2-methyl-1,5-pentanediamine, 2-butyl-2-ethyl-1,5-pentanediamine Aliphatic diamines such as 1,6-hexanediamine, 2,2,4- or 2,4,4-trimethylhexanediamine, 1,8-octanediamine, 1,9-nonanediamine and 1,10-decanediamine; 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane (IPDA), 4,4'-dicyclohexyl Tanjiamin (hydrogenated MDA), isopropylidene cyclohexyl-4,4'-diamine, alicyclic diamine such as 1,4-diaminocyclohexane and 1,3-bis-aminomethyl cyclohexane. Among these, ethylenediamine, propylenediamine, 1,3-pentanediamine and 2-methyl-1,5-pentanediamine are preferable.

These chain extenders are preferably used in an amount of usually 0.1 to 5.0 equivalents and 0.8 to 2 equivalents, where the equivalent of the isocyanate group minus the equivalent of the isocyanate compound is defined as 1. 0.0 equivalent is more preferable, and 0.9 to 1.5 equivalent is still more preferable.

By setting the amount of the chain extender to be not more than the above upper limit, the obtained polyurethane can be prevented from becoming too hard, and desired characteristics can be obtained, and it is easily dissolved in a solvent and easy to process. Moreover, by setting it as the said lower limit or more, sufficient intensity | strength, elastic recovery performance, and elastic retention performance are obtained without being too soft, and favorable high temperature characteristics are obtained.

[1.4] Production of Polyurethane In the present invention, polyurethane is produced by using the polyol, isocyanate compound, and chain extender as main production raw materials in the amounts used as described above, and It can be carried out in the absence of a solvent or in the presence of a solvent by any production method used industrially.

The solvent used in this case is not particularly limited, but N, N-dimethylacetamide, N, N-dimethylformamide, a mixture of two or more thereof, and the like from the viewpoint of versatility and solubility. An amide solvent; a solvent selected from the group consisting of N-methylpyrrolidone, N-ethylpyrrolidone and dimethylsulfoxide is preferably used, and among these, N, N-dimethylformamide and N, N-dimethylacetamide are particularly preferable.

As an example of the production method, a method in which the polyol, the isocyanate compound and the chain extender are reacted together (hereinafter referred to as a one-step method). First, the polyol and the isocyanate compound are reacted to prepare a prepolymer having isocyanate groups at both ends. Then, a method of reacting the prepolymer with the chain extender (hereinafter referred to as a two-stage method) can be mentioned.

Among these, the two-stage method is a process in which a polyol is reacted with one or more equivalents of an isocyanate compound in advance to prepare an intermediate sealed with both terminal isocyanates corresponding to the polyurethane soft segment, In the two-stage method, by preparing a prepolymer and then reacting with a chain extender, it is easy to adjust the molecular weight of the soft segment part, the phase separation of the soft segment and the hard segment is easy to be solidified, and as an elastomer There are features that make it easy to achieve performance.

The temperature at which the polyol, isocyanate compound, and chain extender are mixed is not limited, but is preferably mixed at 10 to 110 ° C. By setting it as 110 degrees C or less, it can prevent that a polyol mixture colors. In addition, by setting the temperature to 10 ° C. or higher, it is possible to prevent a part of the polyol from solidifying, improve work efficiency, prevent non-uniform mixing, and stably produce a polyurethane having excellent peelability and homogeneity. Can be produced.

The reaction temperature when producing polyurethane varies depending on the amount of solvent, the reactivity of raw materials used, reaction equipment, and the like. If the temperature is too low, the progress of the reaction is too slow, or the solubility of the raw materials and the polymer is lowered, so that the productivity is poor. On the other hand, if the temperature is too high, side reactions and polyurethane are decomposed.

The reaction may be performed while degassing under reduced pressure. Moreover, a catalyst, a stabilizer, etc. can also be added for reaction as needed. Examples of the catalyst at that time include triethylamine, tributylamine, dibutyltin dilaurate, stannous octylate, acetic acid, phosphoric acid, sulfuric acid, hydrochloric acid, and sulfonic acid.

Examples of the stabilizer include 2,6-dibutyl-4-methylphenol, distearyl thiodipropionate, di-β-naphthylphenylenediamine, and tri (dinonylphenyl) phosphite.

In the chain extension reaction, it is usually preferable to react each component at 0 to 250 ° C. The reaction temperature varies depending on the amount of solvent, the reactivity of raw materials used, reaction equipment, and the like. If the temperature is too low, the progress of the reaction is too slow, and the solubility of the raw materials and the polymer is low, so that the productivity is poor. On the other hand, if the temperature is too high, side reactions and polyurethane decomposition occur. The reaction may be performed while degassing under reduced pressure.

[1.5] Physical Properties of Polyurethane The polyurethane obtained by the above production method is usually obtained in a state of being dissolved in a solvent because it is usually reacted in the presence of a solvent. It is not limited even in the solid state.

In the present invention, the weight average molecular weight (Mw) of polyurethane by gel permeation chromatography (GPC) varies depending on the use, but is usually preferably 10,000 to 1,000,000, more preferably 50,000 to 500,000, more preferably 100,000 to 400,000. Is more preferable, and 150,000 to 300,000 is particularly preferable.

Further, as a measure of the molecular weight distribution, the ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is preferably 1.5 to 3.5, and preferably 1.7 to 3.0. Is more preferable, and 1.8 to 3.0 is particularly preferable. The number average molecular weight (Mn) can also be measured by the gel permeation chromatography (GPC) described above.

[1.6] Other polyurethanes As other polyurethanes, it is also preferable to use an ultraviolet curable or thermosetting urethane (meth) acrylate as a polyurethane according to the present invention, and it is particularly preferable to use it as a polyurethane for a protective layer. .

As said urethane (meth) acrylate, the said polyol, the said polyisocyanate, and the isocyanate compound which has a (meth) acryloyl group are made to react, or the polyurethane compound obtained by these reaction is (meth) acrylic acid as needed. Can be obtained by esterification.

[1.1] and [1.2] can be referred to for the polyol and the polyisocyanate.

Examples of the isocyanate compound having a (meth) acryloyl group include 2- (meth) acryloyloxyethyl isocyanate, a reaction product of hydroxyethyl (meth) acrylate and isophorone diisocyanate, and pentaerythritol tri (meth) acrylate and isophorone diisocyanate. Examples thereof include a reaction product, a reaction product of dipentaerythritol penta (meth) acrylate and isophorone diisocyanate.

Examples of hydroxy group-containing (meth) acrylates include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, pentaerythritol tri (meth) acrylate, and dipentaerythritol. Examples include penta (meth) acrylate, trimethylolpropane di (meth) acrylate, pentaerythritol tri (meth) acrylate, and dipentaerythritol penta (meth) acrylate.

Specific products of UV curable urethane acrylate include: Nippon Synthetic Chemical Industry Co., Ltd., Shikkou UV-1700B, UV-6300B, UV-7600B, UV-7630B, UV-7630B, UV-7640B, manufactured by Kyoeisha Chemical Co., Ltd. , UA-306H, UA-306T, UA-306I, UA-510H, manufactured by Shin-Nakamura Chemical Co., Ltd., NK Oligo UA-1100H, NK Oligo UA-53H, NK Oligo UA-33H, NK Oligo UA-15HA, ( Examples include AUP787 manufactured by Tokiki Corporation.

Specific examples of the thermosetting urethane acrylate include TOM Co., Ltd., MOTOE-S800C, and the like.

[2] Silicon atom-containing compound The silicon atom according to the present invention is preferably introduced from a silane coupling agent or a polysiloxane derivative.

[2.1] Silane coupling agent The silane coupling agent according to the present invention includes, for example, halogen-containing silane coupling agents (2-chloroethyltrimethoxysilane, 2-chloroethyltriethoxysilane, 3-chloropropyltrimethoxysilane). Silane, 3-chloropropyltriethoxysilane, etc.), epoxy group-containing silane coupling agent [2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, 3- (3,4-epoxycyclohexyl) propyltrimethoxysilane, 2-glycidyloxyethyltrimethoxysilane, 2-glycidyloxyethyltriethoxysilane, 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropyltrie Toxisilane etc.], amino group-containing silane coupling agents (2-aminoethyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2- [N- (2-aminoethyl) amino] ethyl Trimethoxysilane, 3- [N- (2-aminoethyl) amino] propyltrimethoxysilane, 3- (2-aminoethyl) amino] propyltriethoxysilane, 3- [N- (2-aminoethyl) amino] Propyl-methyldimethoxysilane), mercapto group-containing silane coupling agent (2-mercaptoethyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, etc.), vinyl group-containing silane coupling agent ( Vinyltrimethoxysilane, vinyl Triethoxysilane), (meth) acryloyl group-containing silane coupling agents (2-methacryloyloxyethyltrimethoxysilane, 2-methacryloyloxyethyltriethoxysilane, 2-acryloyloxyethyltrimethoxysilane, 3-methacryloyloxypropyltri Methoxysilane, 3-methacryloyloxypropyltriethoxysilane, 3-acryloyloxypropyltrimethoxysilane, etc.). Among these, epoxy group-containing silane coupling agents, mercapto group-containing silane coupling agents, silane coupling agents containing a (meth) acryloyl group, and the like are preferably used.

The epoxy group-containing silane coupling agent is an organosilicon compound having at least one epoxy group (an organic group containing an epoxy group) and at least one alkoxysilyl group in the molecule, and is compatible with the adhesive component. Those having good light transmission properties, for example, substantially transparent are preferable.

Specific examples of the epoxy group-containing silane coupling agent include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltrialkoxysilane such as 3-glycidoxypropyltriethoxysilane, and 3-glycidoxypropyl. 3-glycidoxypropylalkyldialkoxysilane such as methyldiethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, methyltri (glycidyl) silane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- And 2- (3,4-epoxycyclohexyl) ethyltrialkoxysilane such as (3,4-epoxycyclohexyl) ethyltriethoxysilane. Among them, from the viewpoint of further improving the durability, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 2- (3,4 epoxycyclohexyl) ) Ethyltrimethoxysilane is preferred, and 3-glycidoxypropyltrimethoxysilane is particularly preferred. These may be used individually by 1 type and may be used in combination of 2 or more type.

The mercapto group-containing silane coupling agent is an organosilicon compound having at least one mercapto group (an organic group containing a mercapto group) and at least one alkoxysilyl group in the molecule, and has compatibility with other components. Those which are good and have optical transparency, for example, those which are substantially transparent are suitable.

Specific examples of mercapto group-containing silane coupling agents include mercapto group-containing low molecular weight silane coupling agents such as 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, and 3-mercaptopropyldimethoxymethylsilane; 3 -Mercapto group-containing silane compounds such as mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropyldimethoxymethylsilane, methyltriethoxysilane, ethyltriethoxysilane, methyltrimethoxysilane, ethyltrimethoxysilane And a mercapto group-containing oligomer type silane coupling agent such as a cocondensate with an alkyl group-containing silane compound. Among these, from the viewpoint of durability, a mercapto group-containing oligomer type silane coupling agent is preferable, particularly a cocondensate of a mercapto group-containing silane compound and an alkyl group-containing silane compound, and more preferably 3-mercaptopropyltrimethoxysilane and A cocondensate with methyltriethoxysilane is preferred. These may be used individually by 1 type and may be used in combination of 2 or more type.

Examples of the (meth) acryloyl group-containing silane coupling agent include 1,3-bis (acryloyloxymethyl) -1,1,3,3-tetramethyldisilazane, 1,3-bis (methacryloyloxymethyl) -1, 1,3,3-tetramethyldisilazane, 1,3-bis (γ-acryloyloxypropyl) -1,1,3,3-tetramethyldisilazane, 1,3-bis (γ-methacryloyloxypropyl)- 1,1,3,3-tetramethyldisilazane, acryloyloxymethylmethyltrisilazane, methacryloyloxymethylmethyltrisilazane, acryloyloxymethylmethyltetrasilazane, methacryloyloxymethylmethyltetrasilazane, acryloyloxymethylmethylpolysilazane, methacryloyloxymethyl Methyl policy Razan, 3-acryloyloxypropylmethyltrisilazane, 3-methacryloyloxypropylmethyltrisilazane, 3-acryloyloxypropylmethyltetrasilazane, 3-methacryloyloxypropylmethyltetrasilazane, 3-acryloyloxypropylmethylpolysilazane, 3-methacryloyloxy Propylmethylpolysilazane, acryloyloxymethylpolysilazane, methacryloyloxymethylpolysilazane, 3-acryloyloxypropylpolysilazane, and 3-methacryloyloxypropylpolysilazane are preferred, and from the viewpoint that the compound can be easily synthesized and identified, 1,3-bis (Acryloyloxymethyl) -1,1,3,3-tetramethyldisilazane, 1,3-bis (methacryloyloxy) Til) -1,1,3,3-tetramethyldisilazane, 1,3-bis (γ-acryloyloxypropyl) -1,1,3,3-tetramethyldisilazane, 1,3-bis (γ- Particularly preferred is methacryloyloxypropyl) -1,1,3,3-tetramethyldisilazane.

As the silane coupling agent, in addition to the above epoxy group-containing silane coupling agent, mercapto group-containing silane coupling agent and (meth) acryloyl group-containing silane coupling agent, for example, hydroxy group-based silane coupling agent, carboxy group A silane coupling agent, an amino group silane coupling agent, an amide group silane coupling agent, an isocyanate group silane coupling agent, a fluorine silane coupling agent and the like are preferably used.

Examples of the fluorine-based silane coupling agent include CF ₃ (CF ₂ ) ₃ CH ₂ CH ₂ Si (OCH ₃ ) ₃ ; CF ₃ (CF ₂ ) ₅ CH ₂ CH ₂ Si (OCH ₃ ) ₃ ; CF ₃ ( CF ₂ ) ₇ CH ₂ CH ₂ Si (OCH ₃ ) ₃ ; CF ₃ (CF ₂ ) ₉ CH ₂ CH ₂ Si (OCH ₃ ) ₃ ; (CF ₃ ) ₂ CF (CF ₂ ) ₄ CH ₂ CH ₂ Si ( _{OCH 3) 3; (CF 3} ) 2 CF (CF 2) 6 CH 2 CH 2 Si (OCH 3) 3; (CF 3) 2 CF (CF 2) 8 CH 2 CH 2 Si (OCH 3) 3; CF ₃ (C ₆ H ₄ ) C ₂ H ₄ Si (OCH ₃ ) ₃ ; CF ₃ (CF ₂ ) ₃ (C ₆ H ₄ ) C ₂ H ₄ Si (OCH ₃ ) ₃ ; CF ₃ (CF ₂ ) ₅ ( _{C 6} H ₄₎ C 2 H _{Si (OCH 3) 3; CF} 3 (CF 2) 7 (C 6 H 4) C 2 H 4 Si (OCH 3) 3; CF 3 (CF 2) 3 CH 2 CH 2 SiCH 3 (OCH 3) 2; _{CF 3 (CF 2) 5 CH} 2 CH 2 SiCH 3 (OCH 3) 2; CF 3 (CF 2) 7 CH 2 CH 2 SiCH 3 (OCH 3) 2; CF 3 (CF 2) 9 CH 2 CH 2 SiCH ₃ (OCH ₃ ) ₂ ; (CF ₃ ) ₂ CF (CF ₂ ) ₄ CH ₂ CH ₂ SiCH ₃ (OCH ₃ ) ₂ ; (CF ₃ ) ₂ CF (CF ₂ ) ₆ CH ₂ CH ₂ SiCH ₃ (OCH ₃ ) ₂ ; (CF ₃ ) ₂ CF (CF ₂ ) ₈ CH ₂ CH ₂ SiCH ₃ (OCH ₃ ) ₂ ; CF ₃ (C ₆ H ₄ ) C ₂ H ₄ SiCH ₃ (OCH ₃ ) ₂ ; CF ₃ ( CF ₂ ) ₃ (C ₆ H ₄ ) C ₂ H ₄ SiCH ₃ (OCH ₃ ) ₂ ; CF ₃ (CF ₂ ) ₅ (C ₆ H ₄ ) C ₂ H ₄ SiCH ₃ (OCH ₃ ) ₂ ; CF ₃ ( _{CF 2) 7 (C 6 H} 4) C 2 H 4 SiCH 3 (OCH 3) 2; CF 3 (CF 2) 3 CH 2 CH 2 Si (OCH 2 CH 3) 3; CF 3 (CF 2) 5 CH ₂ CH ₂ Si (OCH ₂ CH ₃ ) ₃ ; CF ₃ (CF ₂ ) ₇ CH ₂ CH ₂ Si (OCH ₂ CH ₃ ) ₃ ; CF ₃ (CF ₂ ) ₉ CH ₂ CH ₂ Si (OCH ₂ CH ₃ ) ₃ ; and CF ₃ (CF ₂ ) ₇ SO ₂ N (C ₂ H ₅ ) C ₂ H ₄ CH ₂ Si (OCH ₃ ) ₃ ;

Examples of commercially available silane coupling agents include (meth) acryloyl group-containing silane coupling agents such as KBM-13, KBM-22, KBM-103, KBM-303, KBM- manufactured by Shin-Etsu Chemical Co., Ltd. 402, KBM-403, KBM-502, KBM-503, KBM-602, KBM-603, KBM-802, KBM-803, KBM-903, KBM-1003, KBM-3033, KBM-5103, KBM-7103, KBE-13, KBE-22, KBE-402, KBE-403, KBE-502, KBE-503, KBE-846, KBE-903, KBE-1003, KBE-3033, KBE-9007, LS-520, LS- 530, LS-1090, LS-1370, LS-1382, LS-1890 Mention may be made of the LS-2750, LS-3120.

Commercially available products of fluorine-containing silane coupling agents include commercial products such as MegaFac RS-56, RS-75, RS-76-E, RS-76-NS, RS-78, and RS-90 manufactured by DIC Corporation. Is used as appropriate. As for these silane coupling agents, only 1 type may be used independently and 2 or more types may be used together.

The blending amount of the silane coupling agent and the polysiloxane derivative described later is desirably in the range of 0.1 to 5% by mass with respect to the total solid content of the protective layer and the base material layer. If it is 0.1 mass% or more, the effect of this invention can fully be acquired, and if it is less than 5 mass%, bleeding out is suppressed and the external appearance of films, such as a haze, is not impaired.

(Polymerization initiator)
In general, the silane coupling agent according to the present invention is preferably used in combination with a polymerization initiator. When a polymerization initiator is used, its content is preferably 0.1 mol% or more, more preferably 0.5 to 2 mol% of the total amount of compounds involved in the polymerization. By setting it as such a composition, the polymerization reaction via an active component production | generation reaction can be controlled appropriately. Examples of photopolymerization initiators are Irgacure series (for example, Irgacure 651, Irgacure 754, Irgacure 184, Irgacure 2959, Irgacure 907, Irgacure 369, Irgacure 379, Irgacure 819, etc.) commercially available from BASF Japan. Darocur series (eg, Darocur TPO, Darocur 1173, etc.), Quantacure PDO, Ezacure series (eg, Ezacure TZM, Ezacure TZT, Ecure TZT, Ecure TZT, Ecure Etc.).

[2.2] Polysiloxane derivative It is also preferable to use a polysiloxane derivative in order to make the polyurethane film of the present invention contain silicon atoms.

Specific examples include polysiloxane derivatives such as polysiloxane compounds, polydimethylsiloxane compounds, and polydimethylsiloxane copolymers. Moreover, what combined these compounds may be used.

The compound having a polysiloxane skeleton has a structure represented by the following general formula (I), and changes the number of repetitions n (one or more) in the general formula (I) and the type of the organic modification part. Thus, the surface tension can be arbitrarily controlled.

As an example of changing the type of n or the organically modified part in the general formula (I), for example, a structure represented by the following general formula (II) (x and y are one or more numbers representing the number of repetitions, m is An integer of 1 or more), and the silicone skeleton can be modified by adding a side chain. As the R ¹ in the formula (II), for example, a methyl group, an ethyl group, group and the like. Examples of R ² include a polyether group, a polyester group, and an aralkyl group.

Furthermore, a compound having a structure represented by the following general formula (III) (m is an integer of 1 or more) can also be used, and the silicone chain is composed of several Si—O bonds and corresponds to R ³ . It has an average of one polyether chain and the like.

(Polysiloxane compounds)
Examples of polysiloxane compounds include tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltoxioxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ-glycid. Xylpropyltriethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-methacryloxypropyl Hydrolyzable silicic acid such as methyldimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-acryloxypropyltrimethoxysilane, γ-acryloxypropylmethyldimethoxysilane A partially hydrolyzed product of a silane compound having a group, an organosilica sol in which fine particles of silicic anhydride are stably dispersed in an organic solvent, or the above-mentioned silane compound having radical polymerizability added to the organosilica sol Can be mentioned.

(Polydimethylsiloxane compound)
Polydimethylsiloxane compounds include polydimethylsiloxane, alkyl-modified polydimethylsiloxane, carboxy-modified polydimethylsiloxane, amino-modified polydimethylsiloxane, epoxy-modified polydimethylsiloxane, fluorine-modified polydimethylsiloxane, and (meth) acrylate-modified polydimethylsiloxane. (For example, GUV-235 manufactured by Toagosei Co., Ltd.).

(Polydimethylsiloxane copolymer)
The polydimethylsiloxane copolymer may be any of a block copolymer, a graft copolymer, and a random copolymer, but a block copolymer and a graft copolymer are preferable.

(Commercial materials)
Moreover, as a commercially available material, if it has a silicon atom, it will not specifically limit, For example, what was described below can be used.

Kyoeisha Chemical Co., Ltd .: GL-01, GL-02R, GL-03, GL-04R
Nissin Chemical Industry Co., Ltd .: Silface SAG002, Silface SAG005, Silface SAG008, Silface SAG503A, Surfinol 104E, Surfinol 104H, Surfinol 104A, Surfinol 104BC, Surfinol 104DPM, Surfinol 104PA, Surfinol 104PG-50, Surfinol 104S, Surfinol 420, Surfinol 440, Surfinol 465, Surfinol 485, Surfinol SE
Shin-Etsu Chemical Co., Ltd .: FA-600, KC-89S, KR-500, KR-516, X-40-9296, KR-513, X-22-161A, X-22-162C, X-22-163 X-22-163A, X-22-164, X-22-164A, X-22-173BX, X-22-174ASX, X-22-176DX, X-22-343, X-22-2046, X -22-2445, X-22-3939A, X-22-4039, X-22-4015, X-22-4272, X-22-4741, X-22-4952, X-22-6266, KF-50 -100cs, KF-96L-1cs, KF-101, KF-102, KF-105, KF-351, KF-352, KF-353, KF-354L, KF-355A, KF- 93, KF-615A, KF-618, KF-857, KF-859, KF-860, KF-862, KF-877, KF-889, KF-945, KF-1001, KF-1002, KF-1005, KF-2012, KF-2201, X-22-2404, X-22-2426, X-22-3710, KF-6004, KF-6011, KF-6015, KF-6123, KF-8001, KF-8010, KF-8012, X-22-9002
Made by Toray Dow Corning Co., Ltd .: DOW CORNING 100F ADDITIVE, DOW CORNING 11 ADDITIVE, DOW CORNING 3037 INTERMEDIATE, DOW CORNING 56 GDIWRA TO 104 CORNING TORAY FZ-2222
Made by Kao Corporation: Emulgen 102KG, Emulgen 104P, Emulgen 105, Emulgen 106, Emulgen 108, Emulgen 109P, Emulgen 120, Emulgen 123P, Emulgen 147, Emulgen 210P, Emulgen 220, Emulgen 306P, Emulgen 320P, Emulgen 404, Emulgen 408, Emulgen 409PV, Emulgen 420, Emulgen 430, Emulgen 705, Emulgen 707, Emulgen 709, Emulgen 1108, Emulgen 1118S-70, Emulgen 1135S-70, Emulgen 2020G-HA, Emulgen 2025G, Emulgen LS-106, Emulgen LS-110, Emulgen LS-110 LS114
The molecular weight of the polysiloxane derivative is not particularly limited, but for example, those having a polystyrene-reduced average molecular weight in the range of 500 to 100,000 are preferred, and those having the molecular weight in the range of 1,000 to 50,000 are more preferred.

[2.3] Surfactant In order to contain a silane coupling agent or a polysiloxane derivative in polyurethane, it is preferable to use a surfactant in combination from the viewpoint of uniform mixing. Specifically, hydrocarbons such as NIKKOL BL, BC, BO, BB series manufactured by Nikko Chemicals Co., Ltd., ZONYL FSN, FSO manufactured by DuPont, Surflon S-141, 145 manufactured by Asahi Glass Co., Ltd., DIC ( Fluorine-based products such as MegaFac F-141 and 144 manufactured by Neos Inc., Footogen F-200 and F251 manufactured by Neos Co., Ltd., Unidyne DS-401 and 402 manufactured by Daikin Industries, Ltd., and Fluorard FC-170 and 176 manufactured by 3M Alternatively, a silicone-based nonionic surfactant can be used, and a cationic surfactant, an anionic surfactant, and an amphoteric surfactant can also be used.

[2.4] Organic solvent An organic solvent is preferably used to contain polyurethane with a silane coupling agent or a polysiloxane derivative. Examples of the organic solvent include alcohol solvents, ketone solvents, ester solvents, non-solvents, and the like. Examples include proton solvents.

Here, examples of the alcohol solvent include n-propanol, iso-propanol, n-butanol, iso-butanol, sec-butanol, tert-butanol, n-pentanol, iso-pentanol, 2-methylbutanol, 2- Butoxyethanol, sec-pentanol, tert-pentanol, 3-methoxybutanol, n-hexanol, 2-methylpentanol, sec-hexanol, 2-ethylbutanol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol Monopropyl ether, propylene glycol monobutyl ether, 1-butoxy-2-propanol, 3-methoxy-1-butanol and the like are preferable. These alcohol solvents may be used alone or in combination of two or more.

Examples of ketone solvents include acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl-n-butyl ketone, diethyl ketone, methyl-iso-butyl ketone, methyl-n-pentyl ketone, ethyl-n-butyl ketone, methyl-n-hexyl. In addition to ketone, di-iso-butyl ketone, trimethylnonanone, cyclohexanone, 2-hexanone, methylcyclohexanone, 2,4-pentanedione, acetonylacetone, acetophenone, fenchon, acetylacetone, 2,4-hexanedione, 2 , 4-heptanedione, 3,5-heptanedione, 2,4-octanedione, 3,5-octanedione, 2,4-nonanedione, 3,5-nonanedione, 5-methyl-2,4-hexanedione, 2,2,6,6-tetrame Le-3,5-heptane dione, 1,1,1,5,5,5 beta-diketones such as hexafluoro-2,4-heptane dione and the like. These ketone solvents may be used alone or in combination of two or more.

Examples of ester solvents include diethyl carbonate, ethylene carbonate, propylene carbonate, diethyl carbonate, methyl acetate, ethyl acetate, γ-butyrolactone, γ-valerolactone, n-propyl acetate, iso-propyl acetate, n-butyl acetate, and iso -Butyl, sec-butyl acetate, n-pentyl acetate, sec-pentyl acetate, 3-methoxybutyl acetate, methyl pentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, benzyl acetate, cyclohexyl acetate, methylcyclohexyl acetate, n-acetate -Nonyl, methyl acetoacetate, ethyl acetoacetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, vinegar Acid diethylene glycol mono-n-butyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, di Glycol acetate, methoxytriglycol acetate, ethyl propionate, n-butyl propionate, iso-amyl propionate, diethyl oxalate, di-n-butyl oxalate, methyl lactate, ethyl lactate, n-butyl lactate, n-lactate Examples include amyl, diethyl malonate, dimethyl phthalate, and diethyl phthalate. These ester solvents may be used alone or in combination of two or more.

Aprotic solvents include acetonitrile, dimethyl sulfoxide, N, N, N ′, N′-tetraethylsulfamide, hexamethylphosphoric triamide, N-methylmorpholone, N-methylpyrrole, N-ethylpyrrole, N -Methylpiperidine, N-ethylpiperidine, N, N-dimethylpiperazine, N-methylimidazole, N-methyl-4-piperidone, N-methyl-2-piperidone, N-methyl-2-pyrrolidone, 1,3-dimethyl Examples include -2-imidazolidinone and 1,3-dimethyltetrahydro-2 (1H) -pyrimidinone. The above organic solvent can be used 1 type or in mixture of 2 or more types.

In the present invention, for example, the organic solvent used when forming the protective layer is preferably an alcohol solvent or a ketone solvent among the above organic solvents.

[3] Method for Producing Polyurethane Film Next, an example of a method for producing a polyurethane film will be described, but it is not limited thereto. About the manufacturing method of the polyurethane film of this invention, the manufacturing method of a base material layer and a protective layer is demonstrated.

[3.1] Manufacturing method of base material layer For the base material layer, manufacturing methods such as inflation method, T-die method, calendar method, cutting method, casting method, emulsion method, hot press method, etc. can be used. From the viewpoint of production efficiency, it is preferable to form by a typical melt casting film forming method or solution casting film forming method.

[3.1.1] Melt casting film forming method The polyurethane film is preferably formed by a melt casting film forming method. In the melt casting film forming method, a composition containing an additive such as a polyurethane resin, a silane coupling agent, and a polysiloxane derivative and other additives is heated and melted to a temperature exhibiting fluidity, and then fluidized polyurethane. Refers to casting a melt containing

In the melt casting film forming method, the melt extrusion method is preferable from the viewpoint of mechanical strength and surface accuracy. It is preferable that a plurality of raw materials used for melt extrusion are usually kneaded in advance and pelletized.

Pelletization may be performed by a known method. For example, additives such as dry polyurethane, silane coupling agent, polysiloxane derivative, and other additives are fed to an extruder with a feeder and mixed using a single or twin screw extruder. It can be smelted, extruded from a die into a strand, cooled with water or air, and cut.

Additives may be mixed before being supplied to the extruder, or may be supplied by individual feeders.

A small amount of additives such as particles and antioxidants are preferably mixed in advance in order to mix uniformly.

The extruder is preferably processed at a temperature as low as possible so that it can be pelletized so that the shearing force is suppressed and the resin does not deteriorate (molecular weight reduction, coloring, gel formation, etc.). For example, in the case of a twin screw extruder, it is preferable to rotate in the same direction using a deep groove type screw. From the uniformity of kneading, the meshing type is preferable.

Film formation is performed using the pellets obtained as described above. Of course, the raw material powder can be directly fed to the extruder by a feeder without being pelletized to form a film as it is.

Using a single-screw or twin-screw type extruder, the pellets are melted at a temperature of about 200 to 300 ° C., filtered through a leaf disk type filter or the like to remove foreign matter, and then flowed from the T die into a film. The film is stretched, and the film is nipped with a cooling roller and an elastic touch roller, and solidified on the cooling roller to form a polyurethane film.

When introducing into the extruder from the supply hopper, it is preferable to prevent oxidative decomposition or the like under vacuum, reduced pressure, or inert gas atmosphere.

It is preferable to adjust the extrusion flow rate stably by introducing a gear pump. Further, a stainless fiber sintered filter is preferably used as a filter used for removing foreign substances. The stainless steel fiber sintered filter is a united stainless steel fiber body that is intricately intertwined and compressed, and the contact points are sintered and integrated. The density of the fiber is changed depending on the thickness of the fiber and the amount of compression, and the filtration accuracy is improved. Can be adjusted.

Additives such as plasticizers and particles may be mixed with the resin in advance, or may be kneaded in the middle of the extruder. In order to add uniformly, it is preferable to use a mixing apparatus such as a static mixer.

The temperature of the polyurethane film on the touch roller side when the polyurethane film is nipped between the cooling roller and the elastic touch roller is preferably in the range of Tg to (Tg + 110 ° C.) of the film. A known roller can be used as the roller having an elastic surface used for such purposes.

The elastic touch roller is also called a pinching rotary body. A commercially available one can be used as the elastic touch roller.

When peeling the polyurethane film from the cooling roller, it is preferable to control the tension to prevent deformation of the film.

Moreover, it is preferable that the polyurethane film obtained as described above is stretched by the stretching operation after passing through the step of contacting the cooling roller.

As the stretching method, a known roller stretching machine or tenter can be preferably used. The stretching temperature is preferably performed in the temperature range of Tg to (Tg + 60 ° C.) of the resin constituting the film.

Before winding, the end may be slit and cut to the product width, and knurled (embossed) may be applied to both ends to prevent sticking and scratching during winding. The knurling method can be performed by heating or pressurizing using a metal ring having an uneven pattern on the side surface. In addition, the grip part of the clip at both ends of the film is usually cut out and reused because the polyurethane film is deformed and cannot be used as a product.

It is also preferable to wind up the polyurethane film while laminating the separator.

The separator according to the present invention has a configuration in which a release agent such as silicone is applied to at least a base material for the purpose of adjusting a peeling force or preventing electrification, and is necessary as appropriate from an article to be bonded. Can be peeled off in a simple process. In addition, the said base material may be called a separator.

As for the type of the substrate used for the specific separator, for example, a thermoplastic resin film such as polyester, polyethylene, or polypropylene, or paper is preferable. The substrate is coated with a silicon coat, a polyalkylene coat, or a fluororesin coat. The thing which was done is mentioned. From the viewpoint of dimensional stability, smoothness and peel stability, a polyester film coated with silicon is preferred.

Further, the thickness of the separator is preferably within a range of 10 to 100 μm, and more preferably within a range of 20 to 60 μm. If it is 10 μm or more, the film is not wrinkled by heat during winding, and if it is 100 μm or less, it is preferable from the viewpoint of economy.

[3.1.2] Solution casting film forming method In the solution casting film forming method, an additive such as a polyurethane resin and a silane coupling agent or a polysiloxane derivative, and other additives are dissolved in a solvent to form a dope. The step of preparing, the step of casting the dope on a belt-shaped or drum-shaped metal support, the step of drying the cast dope as a web, the step of peeling from the metal support, the step of stretching or maintaining the width, and further drying And a step of winding up the finished polyurethane film.

The organic solvent useful for forming the dope can be used without limitation as long as it can simultaneously dissolve additives such as polyurethane resin, silane coupling agent or polysiloxane derivative, and other additives. For example, as the chlorinated organic solvent, dichloromethane, as the non-chlorinated organic solvent, methyl acetate, ethyl acetate, amyl acetate, acetone, tetrahydrofuran, 1,3-dioxolane, 1,4-dioxane, cyclohexanone, ethyl formate, 2 , 2,2-trifluoroethanol, 2,2,3,3-tetafluoro-1-propanol, 1,3-difluoro-2-propanol, 1,1,1,3,3,3-hexafluoro-2 -Methyl-2-propanol, 1,1,1,3,3,3-hexafluoro-2-propanol, 2,2,3,3,3-pentafluoro-1-propanol, nitroethane, methanol, ethanol, n -Propanol, iso-propanol, n-butanol, sec-butanol, tert-butanol, etc. It can, dichloromethane, methyl acetate, ethyl acetate, and may be used preferably acetone. The solvent is preferably a dope composition in which a polyurethane resin and other additives are dissolved in a total amount of 15 to 45% by mass.

As the metal support, a stainless steel belt or a drum whose surface is plated with a casting is preferably used.

The cast width can be in the range of 1-4m. The surface temperature of the metal support in the casting step is set to −50 ° C. to below the temperature at which the solvent boils and does not foam. A higher temperature is preferred because the web can be dried faster, but if it is too high, the web may foam or the flatness may deteriorate. A preferable support temperature is appropriately determined in the range of 0 to 100 ° C, and more preferably in the range of 5 to 30 ° C. Alternatively, it is also a preferable method that the web is gelled by cooling and is peeled off from the belt or drum while containing a large amount of residual solvent. The method for controlling the temperature of the metal support is not particularly limited, and there are a method of blowing hot air or cold air, and a method of contacting hot water with the back side of the metal support. The method using warm water is preferable because the heat transfer is performed efficiently, so that the time until the temperature of the metal support becomes constant is short.

When using warm air, considering the temperature drop of the web due to the latent heat of vaporization of the solvent, while using warm air above the boiling point of the solvent, there may be cases where wind at a temperature higher than the target temperature is used while preventing foaming. .

In particular, it is preferable to efficiently dry by changing the temperature of the support and the temperature of the drying air during the period from casting to peeling.

In order to obtain good flatness of the polyurethane film, the amount of residual solvent when peeling the web from the metal support is preferably in the range of 10 to 150% by mass, more preferably in the range of 20 to 40% by mass. Alternatively, it is in the range of 60 to 130% by mass, particularly preferably in the range of 20 to 30% by mass or in the range of 70 to 120% by mass. The amount of residual solvent is defined by the following formula.

Residual solvent amount (% by mass) = {(MN) / N} × 100
Note that M is the mass of a sample collected during or after the production of the web or film, and N is the mass after heating M at 115 ° C. for 1 hour.

In the drying process of the polyurethane film, the web is peeled off from the metal support and dried to make the residual solvent amount 1% by mass or less, more preferably 0.1% by mass or less, and particularly preferably 0%. It is in the range of -0.01% by mass.

In the film drying process, generally, a roller drying method (a method in which webs are alternately passed through a plurality of upper and lower rollers) and a tenter method for drying while transporting the web are employed. In the stretching step, the film can be sequentially or simultaneously stretched in the longitudinal direction (MD direction) and the width direction (TD direction) of the film. The draw ratios in the biaxial directions perpendicular to each other are preferably finally in the range of 1.0 to 2.0 times in the MD direction and in the range of 1.05 to 2.0 times in the TD direction. It is preferable to carry out in the range of 1.0 to 1.5 times in the direction and 1.05 to 2.0 times in the TD direction. For example, a method in which a circumferential speed difference is applied to a plurality of rollers, and the roller circumferential speed difference is used to stretch in the MD direction. Both ends of the web are fixed with clips and pins, and the interval between the clips and pins is increased in the traveling direction. A method of stretching in the MD direction, a method of stretching in the transverse direction and stretching in the TD direction, a method of stretching the MD direction and the TD direction simultaneously, and stretching in both directions.

It is preferable to perform the width maintenance or the stretching in the width direction in the film forming process by a tenter, and a pin tenter or a clip tenter may be used.

The film transport tension in the film forming process such as a tenter depends on the temperature, but is preferably in the range of 120 to 200 N / m, and more preferably in the range of 140 to 200 N / m.

The stretching temperature is in the range of (Tg−30 ° C.) to (Tg + 100 ° C.), more preferably in the range of (Tg−20 ° C.) to (Tg + 80 ° C.), and more preferably, when the glass transition temperature of the polyurethane film is Tg. The range is from (Tg−5 ° C.) to (Tg + 20 ° C.).

[3.1.3] Physical properties of base material layer The thickness of the base material layer is preferably in the range of 2 to 200 μm. More preferably, it is in the range of 100 to 200 μm. The substrate layer (polyurethane film) preferably has a width in the range of 0.5 to 4 m. If it exceeds 4 m, conveyance becomes difficult.

Further, the length of the base material layer (polyurethane film) is preferably in the range of 1000 to 10000 m, more preferably in the range of 1000 to 8000 m, and particularly preferably in the range of 1000 to 4000 m. By setting it as the range of the said length, it is excellent in the productivity and handling property of a polyurethane film.

[3.2] Method for producing protective layer The protective layer is prepared by mixing the polyurethane, the silane coupling agent, the polysiloxane derivative, the polymerization initiator and the organic solvent, and applying the composition onto the base material layer. It is preferable to form by this. It is preferable to use the UV curable urethane acrylate or the thermosetting urethane acrylate as the polyurethane.

The content of polyurethane in the composition is preferably 50% by mass or more, more preferably 70% by mass or more, and particularly preferably 80% by mass or more.

Any appropriate method can be adopted as a method of applying the coating liquid containing the composition. Specific examples include spin coating, roller coating, flow coating, ink jet, spray coating, printing, dip coating, cast film formation, bar coating, and gravure printing. After applying the coating solution, it is preferable to dry the coating film. By drying the coating film, the organic solvent contained in the coating film can be removed. Regarding the formation method, refer to paragraphs “0058” to “0064” of JP-A-2014-151571, paragraphs “0052” to “0056” of JP-A-2011-183773, etc., which are conventionally known. Can do. The thickness of the protective layer is preferably about 2 to 50 μm, more preferably 5 to 30 μm.

In addition, a coating liquid containing the composition is applied onto a release surface of a separator (release film) to form a protective layer, and then the separator with a coating film and the base material layer are laminated, It is also preferable to form a protective layer on the material layer.

FIG. 2 is a schematic view showing an example of a preferred method for producing the polyurethane film of the present invention.

In the polyurethane film of the present invention, the protective layer 3 is applied on the release surface of the separator 4 to form a coated film separator, and the nip roller 5 is used to form the base material layer 2 and the coated film surface of the coated film separator. Can be bonded together (laminating) to form a polyurethane film 1 'with a separator.

The laminating method is not particularly limited. For example, the laminating process may be performed by passing the base layer and the coated film side of the coated film separator through a nip roller under a constant oxygen and moisture concentration environment. It is preferable to carry out while applying pressure. More preferably, it is laminated through a nip roller while applying pressure.

Specifically, when laminating with a nip roller, a nip roller heated to 40 to 120 ° C. is used, or the laminating is preferably performed with a nip pressure of 0.2 to 1.0 MPa. In the case of not heating with a nip roller, it is preferable to perform aging treatment at a temperature of about 30 to 40 ° C. for 1 to 7 days after laminating from the viewpoint of improving the adhesion between the base material layer and the protective layer.

After lamination, the separator prevents the protective layer according to the present invention from being damaged during the handling process. Thereafter, the separator can be peeled off at a necessary stage to make the protective layer the outermost surface.

[4] Other constituent layers Next, constituent layers other than the base material layer and the protective layer, which are used as necessary for the polyurethane film of the present invention, will be described.

[4.1] Anchor coat layer In the polyurethane film of the present invention, if necessary, as an intermediate layer between the base layer and the protective layer, the adhesion between the base layer and the protective layer is improved, and high smoothness is achieved. From the viewpoint of obtaining the above, an anchor coat layer may be formed on the base material layer.

Examples of the anchor coating agent used to form this anchor coat layer include polyester resins, isocyanate resins, urethane resins, acrylic resins, ethylene vinyl alcohol resins, vinyl modified resins, epoxy resins, modified styrene resins, modified silicone resins, and alkyl titanates. Can be used alone or in combination of two or more. Conventionally known additives can be added to these anchor coating agents.

The above-mentioned anchor coating agent is coated on the base material layer by a known method such as roller coating, gravure coating, knife coating, dip coating, spray coating, etc., and the anchor coating layer is formed by drying and removing the solvent, diluent, etc. Can be formed.

The application amount of the anchor coating agent is preferably about 0.1 to 5 g / m ^{2 in} a dry state.

[4.2] Bleed-out prevention layer In the polyurethane film of the present invention, a bleed-out prevention layer may be formed on the back surface of the base material layer.

The bleed-out prevention layer has a protective layer for the purpose of suppressing a phenomenon in which unreacted oligomers migrate from the base material layer to the surface when the film having the protective layer is heated to contaminate the film surface. It is provided on the opposite surface of the base material layer.

In addition, the bleed-out prevention layer may contain a thermoplastic resin, a thermosetting resin, an actinic ray curable resin, a photopolymerization initiator, or the like as a binder.

Examples of the thermoplastic resin include cellulose derivatives such as acetylcellulose, nitrocellulose, acetylbutylcellulose, ethylcellulose, and methylcellulose, vinyl acetate and copolymers thereof, vinyl chloride and copolymers thereof, vinylidene chloride and copolymers thereof, and the like. Resins, acetal resins such as polyvinyl formal, polyvinyl butyral, acrylic resins and copolymers thereof, acrylic resins such as methacrylic resins and copolymers thereof, polystyrene resins, polyamide resins, linear polyester resins, polycarbonate resins, etc. Can be mentioned.

Examples of the thermosetting resin include phenol resin, urea melamine resin, epoxy resin, unsaturated polyester resin, and silicone resin.

The actinic radiation curable resin is cured by irradiating actinic radiation (ultraviolet ray or electron beam) to actinic radiation curable paint in which one or more of photopolymerizable prepolymer or photopolymerizable monomer is mixed. Things can be used. Here, as the photopolymerizable prepolymer, an acrylic prepolymer having two or more acryloyl groups in one molecule and having a three-dimensional network structure by crosslinking and curing is particularly preferably used. As this acrylic prepolymer, urethane acrylate, polyester acrylate, epoxy acrylate, melamine acrylate and the like can be used. Further, as the photopolymerizable monomer, the polyunsaturated organic compounds described above can be used.

Photopolymerization initiators that can be used in combination with actinic radiation curable resins include acetophenone, benzophenone, Michler's ketone, benzoin, benzylmethyl ketal, benzoin benzoate, hydroxycyclohexyl phenyl ketone, 2-methyl-1- (4- (methylthio) phenyl)- 2- (4-morpholinyl) -1-propane, α-acyloxime ester, thioxanthones and the like can be mentioned.

In addition to the binder, the bleed-out prevention layer may contain a matting agent. As the matting agent, inorganic particles having an average particle diameter of about 0.1 to 5 μm are preferable. As such inorganic particles, one or more of silica, alumina, talc, clay, calcium carbonate, magnesium carbonate, barium sulfate, aluminum hydroxide, titanium dioxide, zirconium oxide and the like can be used in combination. . The matting agent composed of inorganic particles is 2 parts by mass or more, preferably 4 parts by mass or more, more preferably 6 parts by mass or more and 20 parts by mass or less, preferably 100 parts by mass of the solid content of the unsaturated organic compound. Is preferably mixed in a proportion of 18 parts by mass or less, more preferably 16 parts by mass or less.

The above bleed-out prevention layer is prepared by blending a binder, a matting agent and other components added as necessary, and adding a predetermined dilution solvent to prepare a coating solution. It can form by apply | coating to the surface of this by the conventionally well-known coating method, and irradiating an active ray and making it harden | cure. As a method of irradiating the actinic radiation, a method of irradiating ultraviolet rays having a wavelength range of 100 to 400 nm, preferably 200 to 400 nm emitted from an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc, a metal halide lamp, or the like, This can be performed by a method of irradiating an electron beam having a wavelength region of 100 nm or less emitted from a scanning or curtain type electron beam accelerator.

The thickness of the bleed-out preventing layer is 1 to 10 μm, preferably 2 to 7 μm. By setting the thickness of the bleed-out prevention layer to 1 μm or more, it becomes easy to make the heat resistance as a polyurethane film sufficient. In addition, by making the thickness of the bleed-out prevention layer 10 μm or less, it becomes easy to adjust the balance of the optical properties of the polyurethane film, and the polyurethane film curls when the protective layer is provided on one surface of the polyurethane film. It becomes possible to make it easy to suppress.

[4.3] Adhesive layer It is preferable to form an adhesive layer containing an adhesive on the back surface side of the polyurethane film of the present invention and to bond it to an article to be bonded.

The pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer is not particularly limited, and examples thereof include acrylic pressure-sensitive adhesives, silicone pressure-sensitive adhesives, urethane pressure-sensitive adhesives, polyvinyl butyral pressure-sensitive adhesives, and ethylene-vinyl acetate pressure-sensitive adhesives. Can do. Moreover, a commercial item may be sufficient and the transparent adhesive sheet LUCIACS CS9621T made from Nitto Denko can be used, for example.

The acrylic pressure-sensitive adhesive used may be either solvent-based or emulsion-based, but is preferably a solvent-based pressure-sensitive adhesive because it is easy to increase the adhesive strength and the like, and among them, those obtained by solution polymerization are preferable. Examples of the raw material for producing such a solvent-based acrylic pressure-sensitive adhesive by solution polymerization include, for example, acrylic acid esters such as ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, and acryl acrylate as main monomers serving as a skeleton, As a comonomer to improve cohesive strength, vinyl acetate, acrylonitrile, styrene, methyl methacrylate, etc., to further promote crosslinking, to give stable adhesive strength, and to maintain a certain level of adhesive strength even in the presence of water Examples of the functional group-containing monomer include methacrylic acid, acrylic acid, itaconic acid, hydroxyethyl methacrylate, and glycidyl methacrylate. Since the adhesive layer of the laminated film requires a particularly high tack as the main polymer, those having a low glass transition temperature (Tg) such as butyl acrylate are particularly useful.

This adhesive layer contains additives such as stabilizers, surfactants, UV absorbers, flame retardants, antistatic agents, antioxidants, thermal stabilizers, lubricants, fillers, coloring, adhesion modifiers, etc. It can also be made.

The thickness of the adhesive layer is preferably in the range of 1 to 50 μm, more preferably in the range of 3 to 40 μm. If it is 1 micrometer or more, there exists a tendency for adhesiveness to improve and sufficient adhesive force is acquired. On the other hand, if it is 50 μm or less, not only the transparency of the polyurethane film is improved, but also after the polyurethane film is attached to the object to be bonded and then peeled off, no cohesive failure occurs between the adhesive layers, and adhesion to the glass surface There is a tendency that there is no remaining agent.

[5] Use of polyurethane film The polyurethane film of the present invention is used in a wide range of fields such as clothing, sanitary goods, packaging, civil engineering, architecture, medical care, automobiles, home appliances, and other industrial parts.

In particular, it can be applied to paint protection film (PPF), which is a car exterior protection film. By attaching the PPF to a new car, it prevents the exterior from being scratched, and when sold as a used car, the car body is damaged. There are advantages such as being able to sell the car high. As a structure, it is common to provide an adhesive layer on the back side of the polyurethane film + polyurethane film + self-healing layer (protective layer referred to in the present application) and bond it to the vehicle body.

The polyurethane film of the present invention has excellent suitability regardless of the usage environment of the car because the peeling of the polyurethane layer is improved in cold areas.

Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In addition, although the display of "part" or "%" is used in an Example, unless otherwise indicated, "mass part" or "mass%" is represented.

The materials for polyurethane films used in the examples are listed below.

<Polyurethane for base material layer>
XUS2098 (Non-yellowing polyether-based thermoplastic polyurethane: TPU (Thermoplastic Polyethane), manufactured by Seadam Co., Ltd., 200 μm thickness) • Esmer URS PX (Non-yellowing caprolactan-based TPU), Nippon Matai Co., Ltd., 150 μm thickness XN-2001 (Non-yellowing polycarbonate-based TPU, pellet form), manufactured by Tosoh Corporation, formed by melt extrusion at 180 ° C., 100 μm thick <Polyurethane for protective layer>
・ AUP787 (UV curable urethane acrylate, coating solution), manufactured by Tokushi Co., Ltd. ・ MOTOE-S800C (containing thermosetting urethane acrylate, coating solution, polysiloxane), manufactured by ATT Co., Ltd. <Silicone rubber and silane coupling agent >
・ KMP-594 (silicone rubber, fine powder of silicone rubber having a structure in which linear dimethylpolysiloxane is cross-linked): manufactured by Shin-Etsu Chemical Co., Ltd. ・ KBM403 (silane coupling agent, epoxy system: 3-glycid (Xypropyltrimethoxysilane): manufactured by Shin-Etsu Chemical Co., Ltd. ・ KBE-9007 (silane coupling agent, isocyanate type): manufactured by Shin-Etsu Chemical Co., Ltd. <Separator>
Commercially available PET film with release agent <Example 1>
Add 1 part by weight of silicone rubber (KMP-594, manufactured by Shin-Etsu Chemical Co., Ltd.) to 100 parts by weight of polycarbonate-based thermoplastic polyurethane pellets (XN-2001, manufactured by Tosoh Corporation), and melt at 180 ° C. with an extruder. After kneading, it was extruded from the T die onto the first cooling roller. After pressing with an elastic touch roller, it was further cooled with a second cooling roller and a third cooling roller to obtain a polyurethane film having a thickness of 100 μm. The surface temperature of the first cooling roller was 110 ° C., the surface temperature of the elastic touch roller was 95 ° C., the surface temperature of the second cooling roller was 60 ° C., and the surface temperature of the third cooling roller was 40 ° C. In this film, the surface in contact with the cooling roller was defined as the back surface side of the base material layer.

<Example 2>
As a base film, a thermosetting urethane acrylate (S800C, containing 1% polysiloxane, manufactured by ATT), on the surface side of a polyether-based thermoplastic polyurethane film (XUS2098, manufactured by Seadam Co., Ltd., thickness 200 μm), A mixture of 100 parts by weight of a solid content (50%) and 25 parts by weight of isocyanate (S800HC, manufactured by ATT Co., Ltd., 80% solid content) was applied so that the thickness after drying was 10 μm. Dried to form a protective layer. After drying, a separator was laminated on the coating film and aged at 40 ° C. for 3 days to obtain a polyurethane film having a thickness of 210 μm.

<Example 3>
As a base film, a UV curable urethane acrylate (AUP787, manufactured by Tokushiki Co., Ltd.) on a surface side of a polycaprolactan-based thermoplastic polyurethane film (Esmer URS PX, manufactured by Nihon Matai Co., Ltd., thickness 150 μm), solid 50%) 100 parts by weight and a silane coupling agent (KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd., solid content 100%) 0.5 parts by weight of a mixture was applied so that the thickness after drying was 10 μm. And dried at 90 ° C. for 3 minutes to form a protective layer. After drying, it was cured under UV irradiation conditions of 400 mJ / cm ² to obtain a polyurethane film having a thickness of 160 μm.

<Example 4>
In Example 3, the amount of the silane coupling agent KBM403 added to the UV curable urethane acrylate was adjusted so that the surface Si amount A / back surface Si amount B described in Table I was 100. Thus, a polyurethane film was obtained.

<Example 5>
In Example 2, the base film was left as it was, and on the surface side, thermosetting urethane acrylate (MOTOE-S800C, containing 1% polysiloxane, manufactured by ATT Co., Ltd., solid content 50%) 100 parts by mass, isocyanate ( MOTOE-S800HC, manufactured by ATT Co., Ltd. (80% solid content) 25 parts by mass and a silane coupling agent (KBE-9007, manufactured by Shin-Etsu Chemical Co., Ltd.) 0.5 parts by mass have a thickness after drying. It apply | coated so that it might become 20 micrometers, it was made to dry at 90 degreeC for 3 minutes, and the protective layer was formed. Thereafter, a separator was laminated on the coating film and aged at 40 ° C. for 3 days to obtain a polyurethane film having a thickness of 220 μm.

<Example 6>
In Example 3, the base film was left as it was, and a thermosetting urethane acrylate (MOTOE-S800C, containing 1% polysiloxane, manufactured by ATT Co., Ltd.) on the release surface of the separator (commercially available PET film with a release agent). , Solid content 50%) 100 parts by mass, isocyanate (MOTOE-S800HC, manufactured by ATT Co., Ltd., solid content 80%) 25 parts by mass, silane coupling agent (KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.) 0. 5 parts by mass of the mixture was applied so that the thickness after drying was 20 μm, and dried at 90 ° C. for 3 minutes to form a protective layer (coating film). After drying, the protective film (coating film) side of the base film and the separator with the coating film is laminated while being pressed so as to face the base film, and is aged at 40 ° C. for 3 days. A polyurethane film having a thickness of 170 μm Got.

<Comparative Example 1>
A polyurethane film having a thickness of 100 μm was obtained in the same manner as in Example 1, except that the silicone rubber was omitted.

<Comparative example 2>
A polyurethane film having a thickness of 160 μm was obtained in the same manner as in Example 3 except that the silane coupling agent was omitted.

<Comparative Example 3>
In Example 3, the addition amount of the silane coupling agent KBM403 added to the UV curable urethane acrylate was adjusted, and the same procedure was performed except that the surface Si amount A / back surface Si amount B described in Table I was 110. Thus, a polyurethane film was obtained.

≪Evaluation≫
(1) Measurement of silicon atom content A cross section of the polyurethane film was observed by SEM (scanning electron microscope: JSM-6060LA, manufactured by JEOL Ltd.), and at the same time, EDX (energy dispersive X-ray fluorescence analyzer, Apollo 40 ( The silicon atom content was measured by using Ametech Co., Ltd.).

The silicon atom content is calculated based on the following formula.

Silicon atom content = (count number at 1.74 keV in EDX (cps)) / (count number at 1.60 keV in EDX (cps))
Ten points were randomly measured from the front or back surface of the polyurethane film in a thickness of 1 μm, and the average value was used. That is, the silicon atom content A on the surface is measured from the interface between the polyurethane film surface and air, the silicon atom content of the part up to 1 μm in the film thickness direction, and the silicon atom content B on the back surface of the polyurethane film is From the air interface on the opposite side, the silicon atom content in a part up to 1 μm in the film thickness direction was measured.

When the polyurethane film has a laminated structure of a base material layer and a protective layer, the silicon atom content A is the silicon atom content on the surface of the protective layer, and the silicon atom content B is determined by the protective layer of the base material layer. It is the silicon atom content on the surface opposite to the certain surface (back surface).

In addition, the internal silicon atom content C is determined by measuring the silicon atom content of the part at 10 points at random in the part when the part having the silicon atom content higher than the surface exists inside by the EDX mapping function. The average value was used. The measurement results are shown in Table I.

(2) Low temperature adhesion Table I shows the results of a peel test conducted in a low temperature environment using the polyurethane films of Examples 1 to 6 and Comparative Examples 1 to 3. After the acrylic pressure-sensitive adhesive was applied to the back side of the base material layer with a thickness of 40 μm, a polyurethane film with pressure-sensitive adhesive was stretched to 200% and bonded to the edge of an aluminum bat (As One, Asa No. 3). After leaving in a −20 ° C. refrigerator for 2 hours, low temperature adhesion was evaluated.

1: Peel off just by touching 2: No change when touched, but peels off when cellophane tape is pressed and peeled 3: Crimped on cellophane tape at the edge and does not peel off (3) Room temperature self-repairing Example 1 Using the polyurethane films of -6 and Comparative Examples 1 to 3, the brass brush part was attached to a friction tester at room temperature (23 ° C), pressed against the surface with a load of 2 kg, and 10 reciprocations on the film at 500 mm / min. The film was allowed to stand at room temperature (23 ° C.) for 1 hour, and then the film was visually observed. “Self-healing” means that when a film surface is scratched or hit by scratching, the wound disappears immediately or in a short period of time without the need for external repair operations. To do.

1: Five or more scratches are visible 2: One to four scratches are visible 3: There is no scratch and cannot be seen Table I shows the above evaluation results.

From the results of Table I, the polyurethane films of Examples 1 to 6, which are the constitution of the present invention, have low temperature adhesion and room temperature self-healing with respect to the polyurethane films of Comparative Examples 1 and 2 that do not contain silicon atoms. It turns out that it is excellent in property.

Moreover, when the polyurethane film of Example 3 and Example 4 and the polyurethane film of the comparative example 3 are compared, the value of the surface Si amount A / the back surface Si amount B satisfies the range (upper limit 100) of the present invention. It turns out that it is excellent in adhesiveness and normal temperature self-repairability. The polyurethane film of Comparative Example 3 was inferior in low temperature adhesion and white turbidity because the amount of the silane coupling agent in the protective layer was too large and bleeded out, and the transparency of the film was lowered.

Furthermore, the polyurethane films of Examples 5 and 6 in which the silicon atom content satisfies the formula (2) are more low temperature adhesive and room temperature self-repairing than the polyurethane films of Examples 1 to 3. I found it excellent.

In particular, as a result of a cycle test in which the sample was repeatedly left to stand at −20 ° C. and a normal temperature environment 1000 times or more, the polyurethane film of Example 6 has lower temperature adhesion and normal temperature self-healing than the polyurethane film of Example 5. Was even better.

The polyurethane film of the present invention is a polyurethane film in which peeling of the polyurethane layer is improved in use in a cold region, and is widely used in clothing, sanitary goods, packaging, civil engineering, architecture, medical care, automobiles, home appliances, and other industrial parts. Available in the field. In particular, the present invention can be applied to a paint protection film (PPF) which is a car exterior protective film.

DESCRIPTION OF SYMBOLS 1 Polyurethane film 1 'Polyurethane film with a separator 2 Base material layer 3 Protective layer 4 Separator 5 Nip roller

Claims (6)

A polyurethane film containing polyurethane and silicon atoms,
A polyurethane film characterized in that the silicon atom content A on the surface of the polyurethane film and the silicon atom content B on the back surface of the polyurethane film satisfy the following formula (1).
Formula (1) 1 <A / B ≦ 100 The polyurethane film according to claim 1, wherein the silicon atom is introduced from a silane coupling agent or a polysiloxane derivative. The polyurethane film according to claim 1, wherein the silicon atom content A on the surface of the polyurethane film and the silicon atom content C inside the polyurethane film satisfy the following formula (2).
Formula (2) 1 <C / A The polyurethane film according to any one of claims 1 to 3, wherein the polyurethane film has a laminated structure, and the laminated structure includes at least a base material layer and a protective layer. It is a manufacturing method of the polyurethane film which manufactures the polyurethane film as described in any one of Claim 1- Claim 4, Comprising:
A method for producing a polyurethane film comprising a step of laminating a plurality of layers containing polyurethane, wherein at least one of the plurality of layers contains silicon atoms. The step of laminating a plurality of layers containing polyurethane comprises a protective layer containing polyurethane and a silane coupling agent or a polysiloxane derivative applied on the release surface of the separator, and a base material layer containing at least polyurethane. The method for producing a polyurethane film according to claim 5, wherein the step of adhering is carried out while pressing with a nip roller.

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