JP2961771B2 - Method for producing polyurethane resin for synthetic leather - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing a polyurethane resin for synthetic leather having excellent abrasion resistance.

(Prior Art) Conventionally, polyurethane resins have been used in many applications by utilizing their excellent mechanical properties and durability. However, polyurethane resins usually have poor abrasion resistance, and have the drawback of low surface lubricity. To compensate for this drawback, silicone resin, silicone oil, cellulose derivatives, polyvinyl chloride resin, AS resin, ABS resin, etc. are added, or polysiloxane dicarboxy in which hydroxyl groups are bonded to both ends of linear polysiloxane. There has been proposed a polyurethane resin obtained by copolymerizing phenol with an organic diisocyanate as a part of a diol component.

(Problems to be Solved by the Invention) However, such a polyurethane resin is superior in abrasion resistance as compared with a conventional polyurethane resin containing no silicone component at all, but its level is still insufficient.

Moreover, such a polyurethane resin has problems such as migration of additives to the surface, hardening, and deterioration of mechanical properties.

(Means for Solving the Problems) The present inventors have conducted intensive studies in order to improve these problems, and as a result, one end is a functional group that is non-reactive with an isocyanate group, and the other end is a functional group. A polyurethane resin having an organopolysiloxyl group in the molecular side chain obtained by reacting an organopolysiloxane having one primary hydroxyl group with an organic diisocyanate as an essential component was obtained using a conventional linear polysiloxane dicarbinol. The inventors have found that the abrasion resistance is extremely superior to that of the polyurethane resin, and have completed the present invention.

That is, the present invention relates to an organopolysiloxane (A) having one end having a non-reactive functional group with an isocyanate group and two other end hydroxyl groups with an aliphatic diisocyanate and / or an alicyclic diisocyanate. (B) is reacted with a poly (alkylene carbonate) diol (C) to form a urethane prepolymer having an isocyanate group at the terminal, and further reacted by adding an organic diamine (D) to have an organopolysiloxyl group as a molecular side chain. An object of the present invention is to provide a method for producing a polyurethane resin for synthetic leather, characterized by obtaining a polyurethane resin.

The molecular side chain in the polyurethane resin having an organopolysiloxyl group in the molecular side chain according to the present invention is a portion which is bonded to the main chain of the polyurethane resin having the largest number of carbon atoms and is branched therefrom. Say.

Further, the polyurethane resin according to the present invention refers to a polyurethane resin consisting of only a urethane bond and a polyurethane polyurea resin consisting of a urethane bond and a urea bond.

The polyurethane resin according to the present invention usually has a molecular side chain,
It is made of a polyurethane resin having an organopolysiloxyl group whose terminal is blocked with a functional group that is non-reactive with an isocyanate group.

Examples of the organopolysiloxyl group having a terminal capped with a non-reactive functional group with an isocyanate group include, for example, an organopolysiloxyl group capped with a trialkylsilyl group or a triarylsilyl group. the _{manner, Si (CH 3) 2 O} n Si (CH 3) 3 _{Si (ph) (CH 3)} O n Si (CH 3) 3 And the like. Of course, the organopolysiloxyl group may be an organopolysiloxyl group in which a polyalkylsiloxyl group and a polyalkylarylsiloxyl group are copolymerized in a random or block manner.

The repeating unit n of the organopolysiloxyl group is usually 10
10001000, preferably 20-100.

The polyurethane resin of the present invention is produced by reacting an organopolysiloxane (A) and a diol (C) other than the organopolysiloxane (A) with an organic diisocyanate (B). Further, the above (A), (B),
When the reaction is carried out using an organic diamine (D) in addition to (C), the obtained polyurethane resin has the above-mentioned (A),
It is particularly preferable because the mechanical properties are improved as compared with the polyurethane resin obtained from only (B) and (C). In this case, only the above (A), (B) and (C) are preliminarily reacted to obtain a urethane prepolymer having a terminal isocyanate group, and then an organic diamine (D) is added for further reaction.

The proportion of the organopolysiloxane (A) used in producing the polyurethane resin according to the present invention is not particularly limited, but the organopolysiloxane (A), the diol (C) other than the component (A), and the organic diamine (D) Is usually 0.1 to 50 parts by weight, preferably 0.5 to 20 parts by weight, based on 100 parts by weight of the total. Within this range, the organopolysiloxane (A)
There is a tendency that the larger the amount of the resin used, the smaller the wear coefficient of the obtained polyurethane resin.

The amount of the organic diisocyanate (B) used is usually 0.95 to 1.10 equivalents when the total amount of active hydrogen of the components (A), (C) and (D) is 1 equivalent.

The reaction of the above components (A), (C) and (D) with the component (B) can be carried out by a conventionally known method, but in a solvent-free or organic solvent, if necessary, in the presence of a catalyst. 30-120 ° C
At a reaction temperature of 1 to 10 hours.

The organopolysiloxane (A) according to the present invention is not particularly limited. Are shown.

The alkyl group or the aryl group represented by R _{1 to} R _{7 in} the general formula [I] usually has 1 to 10 carbon atoms.

X in the general formula [I] is not particularly limited as long as it is a group having two primary hydroxyl groups, and a polyorganosiloxyl group and two primary hydroxyl groups are formed by an ether bond, a carbonyl group, Bond, an amide bond, those bonded with an alkylene chain which may be via an ester bond,
Specifically, for example, Is mentioned.

As the organopolysiloxane of the general formula (I), for example, (However, n is a positive integer.).

The repeating unit n of the organopolysiloxyl group is usually
It is 10 to 1000, preferably 20 to 100. Within this range, as the repeating unit n increases, the wear coefficient tends to decrease.

Polysiloxane (A) represented by the above general formula [I]
Is, for example, an alkyloxyalkanediol and an organopolysiloxane having one end having a silane group, or a dialkanol monocarboxylic acid and an organopolysiloxane having one end having a silane group substituted with a hydroxyl group. Or react a dialkanol monocarboxylic acid with an organopolysiloxane which is a silane group having one end substituted with a hydroxyl group, or replace one end of the dialkanol monocarboxylic acid with an amino group with an amino group. It is obtained by reacting the obtained silane group with an organopolysiloxane.

Raw materials for producing the polysiloxane (A) represented by the general formula [I] include 3-allyloxy-1,2-propanediol, 2-allyloxy-1,3-propanediol, and 3-allyloxy-2- Methyl-1,2-propanediol, 2-allyloxy-2-methyl-1,3-propanediol, 3-allyloxy-2-ethyl-1,2-propanediol, 2-allyloxy-2-ethyl-1,3 -Propanediol, 4-allyloxy-3-methyl-3-hydroxymethyl-butan-1-ol, 3-allyloxy-3
-Methyl-1,5-pentanediol, 4-allyloxy-
Allyloxyalkanediols such as 3-ethyl-3-hydroxymethyl-butan-1-ol, 3-allyloxy-3-ethyl-1,5-pentanediol, and dialkyls such as dimethylolacetic acid, dimethylolpropionic acid, and dimethylolbutyric acid. Roll monocarboxylic acid, dimethylpolysiloxane or methylphenylpolysiloxane with one terminal being a silane group, dimethylpolysiloxane or methylphenylpolysiloxane with one terminal being a silane group substituted with a hydroxyl group, one terminal with an amino group Dimethyl polysiloxane or methyl phenyl polysiloxane, which is a silane group substituted by

Examples of the organic diisocyanate (B) include aromatic diisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate, and naphthalene diisocyanate, hexmethylene diisocyanate, lysine diisocyanate, cyclohexane diisocyanate, isophorone diisocyanate, cis-cyclohexylmethane diisocyanate, xylylene diisocyanate, and tetramethyl diisocyanate. Examples thereof include aliphatic or alicyclic diisocyanates such as xylylene isocyanate. Among them, it is preferable to use an aliphatic diisocyanate or an alicyclic diisocyanate from the viewpoint that the obtained polyurethane resin composition has excellent light resistance.

Diols (C) other than polyorganosiloxane (A)
For example, polyester-based diols, polyether-based diols alone or a mixture thereof can be used. Examples of polyester-based diols include, for example, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, 2,2-dimethyl-1,3-propanediol , 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,8-octanediol, diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol, cyclohexane-1,
4-diol, one or more diols such as cyclohexane-1,4-dimethanol and succinic acid, maleic acid,
Condensates with one or more dicarboxylic acids such as adipic acid, glutaric acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, phthalic acid, isophthalic acid, terephthalic acid, and hexahydroisophthalic acid. Further, ring-opening polymers such as γ-butyrolactone and ε-caprolactone using the above-mentioned diol as an initiator may be mentioned. Examples of the polyether-based diol include ethylene oxide, propylene oxide, butylene oxide, and styrene oxide alone or two or more ring-opened polymers using the diol described above in the section of the polyester-based diol as an initiator. Further, a ring-opening polymer of terahydrofuran is also exemplified.
The poly (alkylene carbonate) diol (C) is, for example, diethylene glycol, triethylene glycol, 1.5-pentanediol, 1.6-hexanediol, dimethyl-1.5-pentanediol, dimethyl-1.6.
It is obtained by condensation of -hexanediol, 1.8-octanediol, cyclohexane-1.4-dimethanol, etc. with diallyl carbonate or dialkyl carbonate, phosgene, chloroformate or the like.

The number average molecular weight of the diol (C) is usually 500 to 4000,
Preferably it is 1000-3000. As the diol (C), a low molecular weight diol that can be used for a polyester diol can be mixed.

As the diol (C), one of the above-mentioned diols or a mixture thereof can be used.

Above all, poly (alkylene carbonate) is excellent in light resistance and hydrolysis resistance of the obtained polyurethane resin.
Use a diol.

Examples of the organic diamine (D) include ethylenediamine, 1,3-propylenediamine, 1,2-propylenediamine, hexamethylenediamine, hydrazine, piperazine, N, N'-diaminopiperazine, 2-methylpiperazine, 4,4 Diamines such as' -diaminodicyclohexylmethane, isophoronediamine and the like can be mentioned, and one or a mixture of two or more thereof can be used.

In the production of the polyurethane resin of the present invention, a monoalcohol, a trifunctional or higher alcohol, an organic monoamine, a trifunctional or higher amine, an organic monoisocyanate, a trifunctional or higher polyisocyanate may be used, if necessary.

In producing the polyurethane resin of the present invention, a catalyst and a stabilizer can be used if necessary. As the catalyst, for example, triethylamine, toluenediamine,
Examples include nitrogen-containing compounds such as morpholine, metal salts such as potassium acetate, zinc stearate and tin octylate, and organic metal compounds such as dibutyltin dilaurate.

As the stabilizer, a stabilizer against ultraviolet rays such as substituted benzotriazoles, a stabilizer against phenol derivatives and the like can be added.

These catalysts and stabilizers can be added at any stage when producing a polyurethane resin.

In the reaction, an organic solvent such as ethyl acetate, butyl acetate, methyl ethyl ketone, toluene, tetrahydrofuran, isopropanol, cyclohexanone, dimethylformamide, cellosolve, cellosolve acetate and the like can be used.

The polyurethane resin of the present invention is usually obtained by a solution reaction, and its non-volatile content is 10 to 70% by weight, and the concentration can be appropriately changed with a solvent at the time of use.

The number average molecular weight of the polyurethane resin of the present invention is 5000 to 10
0000, with a range of 10,000 to 50,000 being particularly preferred.

The polyurethane resin composition of the present invention, if necessary, other resins, antioxidants, ultraviolet absorbers, hydrolysis inhibitors, pigments, dyes, thickeners, defoamers, surfactants,
An antistatic agent, a flame retardant, a deodorant, a dispersant, a tackifier resin, a filler, a crosslinking agent, a magnetic powder, and the like can be added.

In the present invention, together with the polyurethane resin composition, if necessary, other resins commonly used, for example, ordinary polyurethane resin, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl propionate copolymer Commercially available products such as polyvinyl butyfour resin, cellulose resin, polyester resin, epoxy resin, phenoxy resin and polyamide resin can also be used in combination.

Examples of the crosslinking agent include phenol-formaldehyde resin, urea-formaldehyde resin, melamine-formaldehyde resin, organic polyisocyanate, and the like.

Preferred crosslinking agents include the above-mentioned organic diisocyanates and their polymers, polyisocyanates having a difunctional or higher functional polyol as a terminal isocyanate group, and blocked isocyanates in which the functional groups of these polyisocyanates are blocked.
The number average molecular weight of these polyisocyanates is 160-200
0 is preferable, for example, Chris Bon NX, CL-2, CL-50
S, Barnock D-750, DN-950, D-500, D-550 [
Dainippon Ink and Chemicals, Inc.], Death Module L,
R, RF (hereinafter, products of Sumitomo Bayer Urethane Co., Ltd.) and other commercial products of various companies can be used.

The polyurethane resin composition of the present invention is an adhesive, a paint,
It can be used for various applications such as fiber treatment agents, molding materials, synthetic leather raw materials, and magnetic recording medium binders.

Next, the present invention will be described by way of examples, but this is only one mode, and the present invention is not limited only to the examples. In the following, all parts are based on weight.

Example 1 A poly (methylsiloxane) having a silane group at the end was reacted with 2-allyloxy-2-ethyl-1,3-propanediol to obtain 30 parts of a dihydroxyalkylpolysiloxane having a number average molecular weight of 3500 and a number average molecular weight of 2,000. After mixing 470 parts of poly (hexamethylene carbonate) diol, adding 160 parts of isophorone diisocyanate and reacting at 100 ° C. for 2 hours, 1720 parts of dimethylformamide was added to obtain a uniform solution. 78 parts of isophoronediamine was added to this solution to obtain a polyurethane resin solution (A) having a solid content of 30% and a viscosity of 500 poise. The film obtained from this resin solution has an expanding power
620kg / cm ² , elongation at break 310%, stress at 100% elongation 120kg / c
It was m ^2. Further, the retention of tensile strength (which is a measure of light resistance) after irradiating ultraviolet light with a fade meter at a black panel temperature of 83 ° C. for 400 hours was 84%. Furthermore, 70
After 10 weeks of standing in an atmosphere at a temperature of 95 ° C. and a relative temperature of 95%, the expansion force retention (a measure of hydrolysis resistance) was 93%.

Synthetic leather was prepared using the polyurethane resin solution (A).

First, the following skin layer composition liquid was applied on a mat release paper so as to have a solid content of 0.2 mm, and dried at 90 ° C. for 3 minutes. Then the following adhesive layer composition liquid on top of it, solid content film thickness 0.2m
m, and immediately attach a brushed cloth to 120 ° C.
After drying for 3 minutes at room temperature, the mixture was aged at room temperature for 3 days, and the release paper was peeled off to obtain a synthetic leather.

This synthetic leather had a wear coefficient (a measure of surface lubricity) of 0.16 by a surface lubrication measuring machine (Model 14 manufactured by Haydon) under a load of 20 g and a speed of 130 mm / min.
In addition, a flat wear test by the JIS M-403B method [(load 1 kg,
It is a measure of wear resistance with a stroke of 140 mm). ] 250
00-26000 times.

Skin layer compounding solution Polyurethane resin solution (A) 100 parts Dirac L color 30 parts [Coloring agent manufactured by Dainippon Ink and Chemicals, Inc.] Dimethylformamide 20 parts Adhesive layer compounding liquid Chrisbon 4010 100 parts [Dainippon Ink Chemical Industry Co., Ltd. Co., Ltd. polyurethane resin, solid content 50%) Crisbon NX 10 parts [Dainippon Ink and Chemicals Co., Ltd. crosslinker, active ingredient 75
%] Crisbon Axel HM 3 parts [Dainippon Ink and Chemicals, Inc. Catalyst, active ingredient 15
%] Toluene 15 parts Example 2 30 parts of the dihydroxyalkylpolysiloxane having a number average molecular weight of 3500 in Example 1 was changed to 65 parts of dihydroxyalkylpolysiloxane having a number average molecular weight of 6700, and 1720 parts of dimethylformamide in Example 1 was further replaced. A polyurethane resin solution (B) having a solid content of 30.3% and a viscosity of 520 poise was obtained in the same manner as in Example 1 except that the amount was changed to 1800 parts. The light resistance and hydrolysis resistance of this resin film were excellent as in Example 1. Polyurethane resin solution (A)
Using this polyurethane resin solution (B), a synthetic leather was prepared in the same manner as in Example 1.

 Table 1 shows the wear coefficient and wear resistance of the obtained product.

Example 3 30 parts of the dihydroxyalkylpolysiloxane having a number average molecular weight of 3,500 in Example 1 was changed to 70 parts, 470 parts of poly (hexamethylene carbonate) diol in Example 1 was replaced by 430 parts, and 160 parts of isophorone diisocyanate was replaced by 1 part.
Changed to 57 parts and the viscosity was 29.9% solid as in Example 1.
A 470 poise polyurethane resin solution (C) was obtained. The light resistance and hydrolysis resistance of this resin film were excellent as in Example 1.

Using this polyurethane resin solution (C) instead of the polyurethane resin solution (A), synthetic leather was produced in the same manner as in Example 1.

 Table 1 shows the wear coefficient and wear resistance of the obtained product.

Example 4 30 parts of the dihydroxyalkylpolysiloxane having a number average molecular weight of 3,500 in Example 1 was changed to 130 parts, 470 parts of poly (hexamethylene carbonate) diol in Example 1 was 370 parts, and 160 parts of isophorone diisocyanate was 1 part.
The amount was changed to 54 parts and the solid content was 30% and the viscosity was 51 in the same manner as in Example 1.
A 0 poise polyurethane resin solution (D) was obtained. The light resistance and hydrolysis resistance of this resin film were excellent as in Example 1. Using this polyurethane resin solution (D) instead of the polyurethane resin solution (A), a synthetic leather was produced in the same manner as in Example 1.

 Table 1 shows the wear coefficient and wear resistance of the obtained product.

Example 5 470 parts of the poly (hexamethylene carbonate) diol in Example 1 were combined with 440 parts of a poly (hexamethylene carbonate) diol having a number average molecular weight of 2,000 and a number average molecular weight of 2
A polyurethane resin solution (E) having a solid content of 30% and a viscosity of 520 poise was obtained in the same manner as in Example 1 except that the poly (tetramethylene ether) glycol was changed to 30 parts of 000. This polyurethane resin was excellent in light resistance and hydrolysis resistance as in the case of Example 1. Using this polyurethane resin solution (E) instead of the polyurethane resin solution (A), synthetic leather was produced in the same manner as in Example 1.

 Table 1 shows the wear coefficient and wear resistance of the obtained product.

Comparative Example 1 Except that 30 parts of a dihydroxyalkylpolysiloxane having a number average molecular weight of 3500 in Example 1 was changed to 30 parts of a dimethylpolysiloxane having a hydroxyethyl group at both terminals having a number average molecular weight of 2400 (primary hydroxyl groups at both terminals). In the same manner as in Example 1, a polyurethane resin solution (F) having a solid content of 30% and a viscosity of 450 poise was obtained. The same test as in the example was carried out, and the wear coefficient was 0.65 and the wear resistance was 2500 to 3000.

(Effect of the Invention) Since the polyurethane resin of the present invention has an organopolysiloxyl group in the molecular side chain, it has excellent abrasion resistance as compared with the conventional polyurethane resin having an organopolysiloxy chain in the molecular main chain. have.

Therefore, molding materials, synthetic leather,
It can be used for various applications such as magnetic powder binders and coating materials.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-289012 (JP, A) JP-A-1-149882 (JP, A) JP-A 64-75513 (JP, A) JP-A 63-289513 83121 (JP, A) JP-A-62-225516 (JP, A) JP-A-2-60935 (JP, A) JP-A-2-616 (JP, A) JP-A-2-165412 (JP, A) (58) Field surveyed (Int.Cl. ⁶ , DB name) C08G 18 / 61,18 / 65 D06N 3/14 C09D 5 / 23,175 / 04 G11B 5/702

Claims (1)

(57) [Claims] 1. An organopolysiloxane (A) having a non-reactive functional group at one end and two primary hydroxyl groups at the other end, an aliphatic diisocyanate and / or an alicyclic diisocyanate. (B) and poly (alkylene carbonate) diol (C) are reacted to form an urethane prepolymer having terminal isocyanate groups,
Then, an organic diamine (D) is added and further reacted to obtain a polyurethane resin having an organopolysiloxyl group as a molecular side chain, and a method for producing a polyurethane resin for synthetic leather.