KR20170109729A - The composition for coating foam, the coating foam and the preparation method of the coating foam - Google Patents

Abstract

Wherein the curing structure regulating agent comprises a polyfunctional crosslinking agent or inorganic nanoparticles, and the maximum foaming temperature of the foaming agent and the one-minute half-life of the curing agent Wherein the difference in temperature is 15 DEG C or less. Also provided is a coated foam of the composition for foam coating. Preparing a composition for foam coating; And coating and foaming the composition for foaming a coating.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a composition for foaming coating, a coated foam, and a method for producing a coated foam.

Compositions suitable for coating foaming, coated foams made therefrom, and methods of making the coated foams.

Foams manufactured by various foaming methods are used for various purposes throughout the industry. For example, it can be used for bonding between parts of electronic products, interior materials for interior decorations, interior / exterior materials for automobiles, insulation materials, and the like. The foam may also be used as a base material for a double-sided pressure-sensitive adhesive tape. The double-sided pressure-sensitive adhesive tape has a structure in which an adhesive layer is formed on both sides of the substrate, and the thickness and the peeling force are variously designed according to the specific use of the double-sided pressure-sensitive adhesive tape. At this time, the base material of the double-sided pressure-sensitive adhesive tape occupies most of the total thickness of the double-sided pressure-sensitive adhesive tape and affects the peeling property.

Commonly used foams include polyethylene foam or acrylic foam. For example, Korean Patent Laid-Open Publication No. 10-2014-0070235 discloses a foamed composition prepared with carbon dioxide for a polyethylene solvent, and a polyethylene foam produced by extrusion molding such a foamed composition. Also, for example, Korean Patent Laid-Open Publication No. 10-2015-0123368 discloses an acrylic foam formed by curing an acrylic curable resin.

In this way, studies for controlling the physical properties and thickness of the foam material for various applications have been conducted, and a variety of researches have been made on the composition of foams and foam compositions.

One embodiment of the present invention provides a composition for foaming a coating, which is excellent in durability on the basis of a uniform thickness and an appropriate gel content and exhibits excellent physical properties in terms of impact resistance and footing force .

Another embodiment of the present invention is a coated foam of the composition for foam coating, which has a thin film structure of uniform thickness, and provides a coating foam which simultaneously realizes excellent durability, impact resistance and footing force.

Another embodiment of the present invention provides a method for effectively producing a coated foam having appropriate density and thickness and capable of simultaneously realizing the above-mentioned excellent physical properties.

In one embodiment of the present invention, there is provided a curable composition comprising a styrene-butadiene-styrene (SBS) rubber, a foaming agent, a curing agent and a curing structure control agent, wherein the curing structure control agent comprises a polyfunctional crosslinking agent or inorganic nanoparticles, Wherein the difference between the temperature and the one-minute half-life temperature of the curing agent is not more than 15 占 폚.

In another embodiment of the present invention, there is provided a coated foam of the composition for foam coating.

In another embodiment of the present invention, there is provided a process for preparing a composition for foam coating, And coating and foaming the composition for foaming a coating.

The composition for foam coating and the coated foam according to the present invention exhibit improved durability based on the gel content of a desired level, exhibit excellent impact resistance and rigidity, and are applied as a base material of an adhesive tape in terms of thickness uniformity Favorable physical properties can be realized.

In addition, the method for producing the coated foam may provide a method for producing a coated foam having the above-mentioned advantages by using the composition for foam coating at a high process efficiency.

Figure 1 schematically illustrates a cross-section of a coated foam according to one embodiment of the present invention.
Fig. 2 schematically shows a cross-section of a double-sided adhesive tape to which a coated foam according to an embodiment of the present invention is applied as a substrate.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other features and advantages of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which: These embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art to which the invention pertains. Only. Like reference numerals refer to like elements throughout the specification.

In the drawings, the thickness is enlarged to clearly represent the layers and regions. In the drawings, for the convenience of explanation, the thicknesses of some layers and regions are exaggerated.

It will also be understood that when a layer, film, region, plate, or the like is referred to as being "on" or "over" another portion, . Conversely, when a part is "directly over" another part, it means that there is no other part in the middle. In addition, when a layer, film, region, plate, or the like is referred to as being "under" or "under" another portion, . Conversely, when a part is "directly underneath" another part, it means that there is no other part in the middle.

In one embodiment of the present invention, there is provided a curable composition comprising a styrene-butadiene-styrene (SBS) rubber, a foaming agent, a curing agent and a curing structure control agent, wherein the curing structure control agent comprises a polyfunctional crosslinking agent or inorganic nanoparticles, Wherein the difference between the temperature and the one-minute half-life temperature of the curing agent is about 15 ° C or less.

The composition for foam coating is a composition optimized to be applied to a coating foaming method. The coating foaming method is a method for foaming a foam by simultaneously foaming with a coating, which is advantageous for producing a foam having a thin thickness as compared with other foaming methods in which an extrusion foaming method or a coating and foaming step are separated, It is difficult to form a foam having a uniform thickness as the thickness of the foam becomes thinner.

In one embodiment of the present invention, the coating foaming composition comprises styrene-butadiene-styrene (SBS) rubber, and the difference between the maximum foaming temperature of the foaming agent and the one minute half- It is possible to manufacture a foam having a thin film structure of uniform thickness through a coating foaming method by including a satisfactory foaming agent and a curing agent together.

In addition, the composition for foaming coating contains a curing structure regulating agent including a polyfunctional crosslinking agent or inorganic nanoparticles, realizing excellent durability based on an appropriate gel content, and achieving an advantage of simultaneously improving impact resistance and footing force have.

In the present specification, the "maximum foaming temperature" of the foaming agent means the temperature at which the foaming agent expands to its maximum size when heat is applied to the composition for coating foaming. The 'one minute half-life temperature' of the curing agent is a temperature at which the amount of the curing agent is reduced to 1/2 after a lapse of 1 minute from the start of application of heat to the composition for foam coating.

The difference between the maximum foaming temperature of the foaming agent and the one minute half life temperature of the curing agent can be about 15 캜 or less, for example, about 10 캜 or less, for example, about 5 캜 or less. More specifically, the maximum foaming temperature of the foaming agent and the one-minute half-life temperature of the curing agent may be the same. By controlling the difference between the maximum foaming temperature of the foaming agent and the one-minute half-life temperature of the curing agent to the above-mentioned range, the coating foaming composition can be made into a coated foil having a thin film of uniform thickness, Durability can be realized.

The composition for foam coating includes styrene-butadiene-styrene (SBS) rubber. The styrene-butadiene-styrene (SBS) rubber is a copolymer of styrene and butadiene, and is a kind of rubber different from styrene-butadiene rubber (SBR), which is generally referred to as styrene. . Since the composition for foam coating includes styrene-butadiene-styrene (SBS) rubber, puncture, elongation and tensile strength can be realized better than those of other types of rubber such as polyethylene and polyacrylate.

The styrene-butadiene-styrene (SBS) rubber may have a styrene-derived structural unit content of about 20 wt% to about 35 wt%. By using the above-mentioned styrene-butadiene-styrene (SBS) rubber in the above-mentioned composition for foamed coating, it is possible to realize a durability which is further improved and to secure excellent puncture resistance and impact resistance of the coated foam prepared from the above- Can be advantageous.

The styrene-butadiene-styrene (SBS) rubber may have a weight average molecular weight (Mw) of about 100,000 to about 40, for example, about 100,000 to about 15. Thereby, the compatibility of the styrene-butadiene-styrene (SBS) rubber with other components can be improved, and the coating foaming composition can have an appropriate viscosity.

The composition for foaming a coating includes a foaming agent, and the foaming agent has a hollow particle structure. 'Hollow particle' is a hollow spherical particle. In this case, 'spherical shape' does not mean a geometrically perfect spherical shape but means a shape which is usually recognized as a spherical shape. Further, the hollow is meant to mean that the liquid or solid component is not contained, and a gas component that is not visually recognized may be contained.

The foaming agent does not disappear or disappear in the foaming process of the coating foaming composition, and can form a bubble structure in the coated foam as its own form. More specifically, when heat for foaming is applied to the composition for foaming coating, the foaming agent of the hollow particle structure expands and becomes large in size, and the expanded form itself can form a bubble structure in the coated foam.

More specifically, the blowing agent is a core-shell structure, and the core of the blowing agent is selected from the group consisting of a nitrogen (N ₂ ) gas, a hydrocarbon gas, a hydrogen (H ₂ ) gas, Wherein the shell of the foaming agent comprises a thermoplastic resin.

Specifically, the thermoplastic resin of the shell may include one selected from the group consisting of a polyethylene resin, a polyvinyl chloride resin, a polystyrene resin, a polypropylene resin, a polymethyl methacrylate resin, and a combination thereof.

In one embodiment, when the shell of the blowing agent is made of a thermoplastic resin and the core is made of a hydrocarbon gas, heat stability and chemical stability can be easily ensured.

The particle diameter of the blowing agent may be about 10 탆 to about 16 탆. The particle diameter of the foaming agent means the particle diameter of the foaming agent in the composition for foaming coating, and indicates the size of the foaming agent itself before it is expanded by heating. The particle size of the blowing agent can be determined by measuring the diameter of the projected image by an SEM measurement method. When the particle size of the foaming agent is in the above range, the dispersibility in the composition for foaming coating can be excellent and it can be advantageous to secure an appropriate density and surface roughness according to the fine regulation of the bubble size.

The composition for foam coating includes a curing agent, which is chemically crosslinked with the styrene-butadiene-styrene (SBS) rubber to cure the composition for foam coating properly.

For example, the curing agent may include one selected from the group consisting of dibenzoyl peroxide type curing agent, ditertiary butyl peroxide type curing agent, lauryl peroxide type curing agent, and combinations thereof. The curing agent can be used with the styrene-butadiene-styrene (SBS) rubber as compared with the curing agent having another chemical structure by including the curing agent having such a chemical structure, and can exhibit an advantage of realizing excellent durability, and styrene-butadiene- (SBS) resin has the advantage that it can mediate the bond between the resins through a radical, even though it is not modified to have a functional group such as a hydroxyl group or a carboxyl group for the curing reaction.

In one embodiment, the curing agent may comprise a dibenzoyl peroxide-based curing agent or a lauryl peroxide-based curing agent, and in other embodiments, the curing agent may include a dibenzoyl peroxide-based curing agent. In this case, it is advantageous that the difference between the maximum foaming temperature of the foaming agent and the one-minute half-life temperature of the curing agent satisfies the above-mentioned range, and the coating foam formed from the coating foaming composition can realize improved durability and impact resistance.

The composition for foam coating includes the curing agent and the foaming agent together with the styrene-butadiene-styrene (SBS) rubber. By using them at an appropriate ratio, the effect of improving the durability can be maximized.

For example, the composition for foam coating may comprise about 1 to about 10 parts by weight of the curing agent per 100 parts by weight of the styrene-butadiene-styrene (SBS) rubber, for example, about 3 to about 5 Weight part. By using the above-mentioned curing agent in such an amount, compatibility with the styrene-butadiene-styrene (SBS) rubber is improved, the durability can be improved through the composition for foam coating and releasability due to proper adhesiveness of the surface can be obtained .

The coating foam composition may contain about 0.1 to about 1 part by weight of the foaming agent per 100 parts by weight of the styrene-butadiene-styrene (SBS) rubber, for example, about 0.2 to about 0.4 part by weight . By using such a foaming agent in such an amount, compatibility with the styrene-butadiene-styrene (SBS) rubber is improved, and the durability can be improved through the composition for foam coating and desired specific density and thickness can be obtained.

The composition for foam coating may further contain one selected from the group consisting of carbon black, titanium dioxide (TiO ₂ ), and combinations thereof within a range that does not deteriorate the required physical properties and effects. By further including this, the coated foam prepared from the composition for foam coating can exhibit an appropriate color.

The composition for foam coating includes a curing structure control agent. The curing structure control agent is an additive that forms an additional curing structure in addition to curing by crosslinking of the styrene-butadiene-styrene (SBS) rubber with a curing agent. The composition for foam coating can simultaneously realize improved impact resistance and footing force have.

The cure structure modifying agent may include a polyfunctional crosslinking agent, inorganic nanoparticles, or both.

The multifunctional crosslinking agent is a compound having at least two functional groups that can chemically react with the styrene-butadiene-styrene (SBS) rubber to form an additional crosslinked structure, and examples thereof include polythiol compounds, polyacrylate compounds, And combinations thereof.

The polythiol compound is a compound having two or more thiol groups in one molecule, and may include, for example, a trifunctional to pentafunctional polythiol compound, and may include, for example, a tetrafunctional polythiol compound have. Since the polyfunctional crosslinking agent includes the polythiol compound having the thiol group within the above range, the impact resistance and the footing force improving effect of the composition for foam coating can be increased.

The polyacrylate compound is a compound having two or more acrylate groups in one molecule, and may include, for example, trifunctional or hexafunctional polyacrylate compounds. Since the polyfunctional crosslinking agent includes a polyacrylate compound having an acrylate group within the above range, the effect of improving the impact resistance and footing force of the composition for foam coating can be enhanced.

The inorganic nanoparticles are disposed between the styrene-butadiene-styrene (SBS) rubber and the curing agent or the polyfunctional crosslinking agent when they chemically react to form a curing structure to effectively control the curing structure.

The inorganic nanoparticles may have a particle size of from about 1 nm to about 10 μm, for example, from about 100 nm to about 500 nm. The inorganic nanoparticles may be mixed with particles having various particle sizes within the above range.

The particle size of the inorganic nanoparticles is the largest length or diameter measured for one particle, and can be measured by SEM, TEM or the like.

When the particle size of the inorganic nanoparticles satisfies the above range, the cured structure can be easily controlled, and the effect of improving the impact resistance and footing force of the composition for foam coating can be enhanced.

The inorganic nanoparticles may be formed of a layered silicate. The silicate of the layered structure is an inorganic compound in which a layer of a plate-like silicate is piled up. Since the inorganic nanoparticles are composed of a layered silicate, it is easy to control the curing structure of the styrene-butadiene-styrene (SBS) rubber.

The silicate of the layered structure is an inorganic compound formed by bonding one or more kinds of metal oxide with silica (SiO ₂ ), and the metal oxide is an aluminum oxide, a potassium oxide, a calcium oxide, a magnesium oxide, And combinations thereof.

The composition for foam coating may contain about 0.5 parts by weight or more and less than about 2 parts by weight of the curing structure control agent per 100 parts by weight of the styrene-butadiene-styrene (SBS) rubber, Parts by weight or more, and less than about 1.5 parts by weight. When the content of the curing structure control agent is within the above range, a curing structure for improving both the impact resistance and the releasing force to a desired level can be formed. If the content exceeds the above range, the elongation may decrease.

The above composition for foam coating can significantly improve the impact resistance and the footing force by satisfying the content of the curing agent and the curing structure regulating agent in the above-mentioned ranges, respectively, compared to the styrene-butadiene-styrene (SBS) rubber.

In another embodiment of the present invention, there is provided a coated foam of the composition for foam coating.

Specifically, the above-mentioned coated foam is a molded product obtained by processing the above-mentioned composition for foaming coating by a method of coating foaming, and has a thin film structure having a uniform thickness compared with a molded article produced by applying the composition for foaming coating to other foaming methods such as extrusion foaming Can be easily secured, and excellent surface physical properties and durability can be realized. In addition, it is possible to simultaneously exhibit improved impact resistance and rigidity.

Figure 1 schematically illustrates a cross-section of a coated foam 100 according to one embodiment of the present invention.

Referring to FIG. 1, the coated foam 100 comprises a bubble A. As described above, the bubble (A) is formed by a structure in which the foaming agent of the coating foaming composition is expanded by heat, and the foaming agent is expanded by heat to function as the bubble (A) itself.

At this time, the diameter of the bubble (A) may be about 30 탆 to about 40 탆. When the particle diameter of the bubble (A) satisfies the above range, an appropriate density and surface roughness can be realized in consideration of the thickness of the coated foam. The particle size of the bubbles can be obtained by photographing a cross section of the coated foam by SEM or TEM and measuring the diameter of the bubbles in the projected image.

2 schematically shows a cross-section of a double-faced adhesive tape to which the coated foam 100 according to an embodiment of the present invention is applied as a substrate. Referring to FIG. 2, the coated foam 100 may be applied as a base of a double-sided pressure-sensitive adhesive tape by forming an adhesive layer 10 on both sides thereof.

That is, the coated foam may be used as a base for a double-faced adhesive tape. Specifically, the double-sided pressure-sensitive adhesive tape is applied to general electronic products, and it is an important factor to secure excellent scratch resistance and impact resistance. There is an advantage that it is easy to secure the scratch resistance and impact resistance required by using the coated foam as a base material of the double-sided pressure-sensitive adhesive tape.

The thickness of the coated foam can be from about 100 [mu] m to about 200 [mu] m, for example from about 120 [mu] m to about 180 [mu] m. The thickness of the coated foam satisfies the above range, the thickness uniformity can be excellent, and desired density and roughness can be obtained.

In another embodiment of the present invention, there is provided a process for preparing the coated foam. Specifically, the method for producing the coated foam includes the steps of: preparing the composition for foam coating; And coating and foaming the composition for foam coating.

As described above, the composition for foaming coating comprises a foaming agent and a curing agent that satisfy a condition that the difference between the maximum foaming temperature of the foaming agent and the one-minute half-life temperature of the curing agent is about 15 ° C or less, It is possible to prepare a foam having a thin film structure of

In addition, the composition for foam coating contains a curing structure regulating agent including a polyfunctional crosslinking agent or inorganic nanoparticles, realizing excellent durability based on an appropriate gel content, and simultaneously realizing improved physical properties in terms of impact resistance and footing force have.

The difference between the maximum foaming temperature of the foaming agent and the one minute half-life temperature of the curing agent can be about 15 캜 or less, for example, about 10 캜 or less, for example, about 5 캜 or less. More specifically, the maximum foaming temperature of the foaming agent and the one-minute half-life temperature of the curing agent may be the same. By controlling the difference between the maximum foaming temperature of the foaming agent and the one-minute half-life temperature of the curing agent to the above-mentioned range, the coating foaming composition can be made into a coated foil having a thin film of uniform thickness, Durability can be realized.

The coated foam may be prepared by the method of producing the coated foam, and the foam structure and thickness uniformity of the coated foam may be suitably controlled by the method of producing the coated foam.

Specifically, the method for producing the coated foam includes the step of preparing a coating foaming composition comprising the styrene-butadiene-styrene (SBS) rubber, a foaming agent, a curing agent, and a curing structure control agent. The composition for foaming coating and each component are as described above.

The step of preparing the coating foaming composition may be carried out by first mixing the curing agent and the foaming agent, followed by mixing the styrene-butadiene-styrene (SBS) rubber. By mixing the respective components of the above-mentioned coating foaming composition in this order, it is advantageous to control the density and thickness by increasing the dispersibility of the foaming agent as compared with the case of mixing in the other order.

In addition, the curing structure control agent may be mixed with the styrene-butadiene-styrene (SBS) rubber in the preferentially mixed curing agent and the blowing agent.

In addition, the method for producing the coated foam includes coating and foaming the composition for foaming the coating. At this stage, the composition for foaming the coating is simultaneously subjected to foaming and curing. The coating foaming composition can be foamed so that foaming and curing are performed at the same time, so that a thin film-like coated foam having a uniform thickness can be produced, and a low-roughness surface and a desired density can be obtained.

Specifically, the coating foaming can be performed by coating the coating foaming composition at a normal pressure in a thin film form, and then applying heat at a predetermined temperature. A method of applying heat to the composition for foam coating is not particularly limited, but an oven can be used.

At this time, the step of coating and foaming the composition for foaming coating is a condition that the maximum foaming temperature of the foaming agent is ± 15 ° C; And the one-minute half-life temperature of the curing agent is within a range of +/- 15 ° C.

Specifically, the 'maximum foaming temperature' of the foaming agent refers to the temperature at which the foaming agent expands to its maximum size when heat is applied to the composition for foaming coating. The 'one minute half-life temperature' of the curing agent is a temperature at which the amount of the curing agent is reduced to 1/2 after a lapse of one minute from the start of applying heat to the composition for foam coating.

Specifically, when the coating foaming is performed, heat is applied to the composition for foaming the coating, wherein the heating temperature satisfies both of the conditions of the maximum foaming temperature of the foaming agent ± 15 ° C and the one minute half-life temperature of the curing agent ± 15 ° C . More specifically, the heating temperature may be ± 10 ° C., for example ± 5 ° C., from the one minute half-life temperature of the curing agent.

By satisfying the above-mentioned temperature conditions of the coating foaming, the foam structure and thickness uniformity of the coated foam produced by the above-mentioned production method can be formed to be excellent. For example, the coated foam produced by the above-described method can be used as a base for a double-sided pressure-sensitive adhesive tape as described above. At this time, a bubble structure capable of realizing excellent durability can be secured. So that the structural properties of the double-sided pressure-sensitive adhesive tape can be improved.

Hereinafter, specific embodiments of the present invention will be described. However, the embodiments described below are only intended to illustrate or explain the present invention, and thus the present invention should not be limited thereto.

< Example  And Comparative Example >

Example  One

0.3 parts by weight of a blowing agent (Akzonobel, Expancel DU) having a particle diameter of 10 mu m before foaming and a maximum foaming temperature of 135 DEG C per 100 parts by weight of styrene-butadiene-styrene (SBS) rubber, 5 parts by weight of a dibenzoyl peroxide type curing agent (ACROS, Dibenzoyl Peroxide), 1 part by weight of a polythiol compound having four thiol groups, and 0.5 part by weight of carbon black were mixed to prepare a coating foaming composition. At this time, the foaming agent and the curing agent were first mixed, and then the styrene-butadiene-styrene (SBS) rubber and the polythiol compound were mixed. The composition for foaming the coating was coated on a release polyethylene terephthalate (PET) and heated in an oven at 130 캜 for 3 minutes to prepare a coating foam having a thickness of 150 탆.

Example  2

Inorganic nanoparticles composed of a layered silicate prepared from aluminum oxide and silica (SiO ₂ ) having a particle size of 100 nm were mixed with 100 parts by weight of styrene-butadiene-styrene (SBS) rubber in place of the polythiol compound. Except that the weight of the coating foam was 20 parts by weight, the coating foam of the same thickness was prepared in the same manner as in Example 1 above.

Comparative Example  One

Except that 5 parts by weight of a ditertiary butyl peroxide curing agent (Aldrich, Luperox? DI) having a half-life temperature of 1 minute at 193 占 폚 was used per 100 parts by weight of styrene-butadiene-styrene (SBS) rubber. Coating foams of the same thickness were prepared in the same manner.

Comparative Example  2

A coating foam of the same thickness was prepared in the same manner as in Example 1, except that the polythiol compound was not contained at all.

The properties of the components of the coating and foaming compositions of Examples and Comparative Examples are shown in Table 1 below.

ingredient Example 1 Example 2 Comparative Example 1 Comparative Example 2 SBS Rubber Mw 11 million 11 million 11 million 11 million Styrene content 31 wt% 31 wt% 31 wt% 31 wt% blowing agent Particle diameter before foaming 10 탆 10 탆 10 탆 10 탆 Maximum foaming temperature 135 ℃ 135 ℃ 135 ℃ 135 ℃ Hardener 1 minute half-life temperature 130 ℃ 130 ℃ 193 ° C 130 ℃ Curing structure control agent Polythiol compound ○ - ○ - Layered silicate - ○ - -

<Evaluation>

Experimental Example  1: Measurement of gel content

For each of the coated foams of the above Examples and Comparative Examples, the initial weight (Wi) was measured for a specimen obtained by cutting it to a predetermined size. Subsequently, the specimen was immersed in toluene solvent for 24 hours, then filtered using a mesh having a known weight (Wm), dried in an oven at 110 DEG C for 2 hours, and then measured for weight (Wf) Respectively. The gel content was then determined by the following formula 1, and the results are shown in Table 2 below.

[Formula 1]

Gel content (%) = {(Wf-Wm) / Wi} x 100

Experimental Example  2: Evaluation of impact resistance

On each of the coated foams of Examples and Comparative Examples, an acrylic adhesive layer having a thickness of 50 mu m was formed on both sides to prepare a double-sided pressure-sensitive adhesive tape. Each of the double-faced pressure-sensitive adhesive tapes was then formed into specimens of 0.7 mm x 20 mm x 4 A, and the specimens were attached between the polycarbonate (PC) substrate and the glass substrate. Then, a weight having a weight of 100 g was dropped by the Dupont type test method to measure the weight and height when the double-sided adhesive tape was separated from the substrates. The impact energy (mJ) was calculated using the above weight and height, and the results are as shown in Table 2 below.

Experimental Example  3: Foot force  evaluation

On each of the coated foams of Examples and Comparative Examples, an acrylic adhesive layer having a thickness of 50 mu m was formed on both sides to prepare a double-sided pressure-sensitive adhesive tape. Each of the double-faced pressure-sensitive adhesive tapes was then formed into specimens of 0.7 mm x 20 mm x 4 A, and the specimens were attached between the polycarbonate (PC) substrate and the glass substrate. Then, the force (kgf) required to peel off the specimen and the glass substrate surface at a peeling rate of 20 mm / min was measured. The results are shown in Table 2 below.

Experimental Example  4: Evaluation of durability

After the artificial sebum was applied to the surface of the specimen for evaluating the above-mentioned footing force, the footing force after being left for 72 hours using a thermo-hygrostat device under the conditions of a temperature of about 85 캜 and a relative humidity of about 85% . &Lt; / RTI &gt; The results are shown in Table 2 below.

Gel content (%) durability Impact resistance Push-out Example 1 63.2 0.05kgf 318.5 mJ 3.6kgf Example 2 64.0 0.05kgf 294mJ 3.5kgf Comparative Example 1 0 Not measurable 245mJ 2.7kgf Comparative Example 2 73.7 0.015kgf 294mJ 3.0kgf

Referring to the results of Tables 1 and 2 above, the coated foams made from the composition for coating foaming according to one embodiment of the present invention satisfy a gel content of about 60% to about 70%, and more preferably about 290 mJ or more For example, an impact energy of about 290 mJ to about 320 mJ and a treading force of about 3.5 kgf or more, for example, about 3.5 kgf to about 4.0 kgf, thereby achieving an improved impact resistance and durability at the same time have. Furthermore, even after being left in a high temperature and high humidity environment for a long time, it can be seen that excellent durability and reliability are realized by exhibiting a tensile force of about 0.05 kgf or more, for example, about 0.05 kgf to about 1.0 kgf.

100: Coated foam
10: Adhesive layer
A: Bubble

Claims (18)

Styrene-butadiene-styrene (SBS) rubber, a blowing agent, a curing agent and a curing structure control agent,
Wherein the curing structure control agent comprises a polyfunctional crosslinking agent or inorganic nanoparticles,
The difference between the maximum foaming temperature of the foaming agent and the one-minute half-life temperature of the curing agent is not more than 15 ° C
Composition for foaming coating.
The method according to claim 1,
The styrene-butadiene-styrene (SBS) rubber has a styrene-derived structural unit content of 20 wt% to 35 wt%
Composition for foaming coating.
The method according to claim 1,
Wherein the foaming agent has a particle diameter of 10 mu m to 16 mu m
Composition for foaming coating.
The method according to claim 1,
The foaming agent is a core-shell structure,
The core of the blowing agent comprises one selected from the group consisting of nitrogen (N ₂₎ gas, hydrocarbon gas, hydrogen (H ₂₎ gas, and combinations thereof,
Wherein the shell of the blowing agent comprises a thermoplastic resin
Composition for foaming coating.
The method according to claim 1,
The curing agent includes one selected from the group consisting of dibenzoyl peroxide type curing agent, ditertiary butyl peroxide type curing agent, lauryl peroxide type curing agent, and combinations thereof
Composition for foaming coating.
The method according to claim 1,
(1) to (10) parts by weight of the curing agent relative to 100 parts by weight of the styrene-butadiene-styrene (SBS) rubber
Composition for foaming coating.
The method according to claim 1,
Wherein 0.1 to 1 part by weight of the blowing agent is added to 100 parts by weight of the styrene-butadiene-styrene (SBS) rubber
Composition for foaming coating.
The method according to claim 1,
Wherein the polyfunctional crosslinking agent comprises one selected from the group consisting of a polythiol compound, a polyacrylate compound, and combinations thereof
Composition for foaming coating.
9. The method of claim 8,
The polythiol compound is a trifunctional to pentafunctional polythiol compound
Composition for foaming coating.
9. The method of claim 8,
The polyacrylate compound is a trifunctional to hexafunctional polyacrylate compound
Composition for foaming coating.
The method according to claim 1,
The inorganic nanoparticles have a particle size of 1 nm to 10 [
Composition for foaming coating.
The method according to claim 1,
The inorganic nanoparticles are composed of a layered silicate
Composition for foaming coating.
The method according to claim 1,
Wherein the curing structure regulating agent is contained in an amount of not less than 0.5 parts by weight and less than 2 parts by weight based on 100 parts by weight of the styrene-butadiene-styrene (SBS) rubber
Composition for foaming coating.
14. Coated foam of a composition for foaming a coating according to any one of the preceding claims.
15. The method of claim 14,
Said coated foam comprising bubbles,
The bubbles have a particle diameter of 30 탆 to 40 탆
Coated foam.
15. The method of claim 14,
Used as a substrate for double-sided adhesive tape
Coated foam.
14. A process for producing a coating composition according to any one of claims 1 to 13, which comprises: preparing a composition for foaming a coating according to any one of claims 1 to 13; And
And coating and foaming the composition for foaming the coating
&Lt; / RTI &gt;
18. The method of claim 17,
The coating and foaming of the composition for foaming a coating may include:
The maximum foaming temperature of the foaming agent is 占 15 占 폚; And the one-minute half-life temperature of the curing agent is within a range of +/- 15 DEG C
&Lt; / RTI &gt;

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