JP2688779B2 - Synthetic leather - Google Patents

Description

TECHNICAL FIELD The present invention relates to synthetic leather having excellent surface smoothness.

[Problems to be solved by conventional technology and invention]

Synthetic leather used for furniture, automobile seats, door linings, shift lever boots, etc. has a polyurethane skin layer formed by a wet or dry method on a fiber substrate such as non-woven fabric, woven fabric, or knit fabric. However, this kind of synthetic leather is apt to generate an unpleasant scratching noise when the polyurethane skin layer is rubbed. This is due to lack of lubricity on the surface of the skin layer.Therefore, in conventional synthetic leather, in order to impart lubricity to the surface, silicone oil is added to the polyurethane constituting the skin layer or the surface of the skin layer is A method of forming a silicone oil film by spraying silicone oil on the above has been adopted. However, in such a method, sufficient lubricity is not imparted, or the obtained surface lubricity is temporary and poor in sustainability, and it is still insufficient for applications requiring permanent surface lubricity. It was a thing.

[Means for solving the problem]

The present invention has been made in view of the above points, and an object of the present invention is to provide a synthetic leather which has a long-lasting surface slipping effect and can permanently prevent generation of scratching noise.

That is, the present invention provides a synthetic leather characterized in that the surface of a polyurethane skin layer has a surface treatment layer containing a silicone oil and / or a modified silicone oil and formed of polyurethane containing a silicone diol in a polyol component. It is a summary.

〔Example〕

 An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows one embodiment of the synthetic leather 1 of the present invention. The synthetic leather 1 is provided with a polyurethane skin layer 4 on the surface of a fiber base material 2 with an adhesive layer 3 interposed between the polyurethane skin layer 4 and the polyurethane skin layer 4. The surface treatment layer 5 is provided on the surface.

As the fiber base material 2, for example, natural fibers such as cotton and hemp, regenerated fibers such as rayon, suf, and acetate, synthetic fibers such as polyester, polyamide, and polyacrylonitrile are knitted, woven, or woven or A knitted fabric, a woven fabric, a non-woven fabric or the like which is entangled is used.

The adhesive constituting the adhesive layer 3 may be any adhesive as long as it can bond the fiber base material 1 and the polyurethane skin layer 4, but a urethane-based adhesive is usually used. The urethane adhesive preferably has a 100% modulus of 10 to 100 kg / cm ² , and the polyurethane in this urethane adhesive is polycarbonate polyurethane, polytetramethylene ether polyurethane, polypropylene ether polyurethane, polyester ether polyurethane. , Polyester-based polyurethane and the like. Examples of the polyurethane cross-linking agent used for the urethane-based adhesive include trimethylolpropane (TMP) and TDI adducts, TMP and HMDI adducts, TMP and IPDI adducts, and HMDI trimers. The amount of the crosslinking agent added is 5 to 30 parts by weight based on 100 parts by weight of polyurethane (polyurethane solid content). If the amount of the crosslinking agent is too small, the adhesive strength will be insufficient, and if it is too large, it will be too hard. Further, an amine catalyst is added to the urethane adhesive as a cross-linking accelerator if necessary. The thickness of the adhesive layer 3 is preferably 10-100 μm. The adhesive layer 3 can be colored if necessary.

Polyurethane The skin that makes up the skin layer 4 is 100
Those having a% modulus of 20 to 200 kg / cm ² are preferable, and examples of the polyurethane include polycarbonate polyurethane, polytetramethylene ether polyurethane, polyester ether polyurethane, and polyester polyurethane. The thickness of the skin layer 4 is preferably 10-100 μm. If necessary, a thin film layer made of polyurethane may be further provided on the surface of the skin layer 4. The polyurethane that constitutes this thin film layer has a 100% modulus of 60 to 600 kg / c.
Those having a yield value of m ² and particularly 200 to 600 kg / cm ² are preferable, and as the kind of polyurethane, the same polyurethane as that forming the skin layer 4 can be mentioned. The polyurethane skin layer 4 is formed, for example, by coating and drying a surface layer-forming polyurethane liquid on the surface of a release paper with a squeeze to form a film, and then applying an adhesive to the surface of the film. It can be formed by a dry method of stacking and releasing the release paper after the adhesive is solidified to transfer it.

The polycarbonate-based polyurethane is a polymer of a polycarbonate-based polyol, a diisocyanate compound and a chain extender, and the polycarbonate-based polyol is generally preferably a polyalkylene-polycarbonate-based polyol, and more preferably a 1,6-hexanepolycarbonate-based polyol. A mixture of the above polyalkylene polycarbonate-based polyol and polyether-based polyol can also be used. The diisocyanate compound to be reacted with this polycarbonate-based polyol is tolylene diisocyanate (TDI), diphenylmethane diisocyanate, xylylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HMDI), isophorone diisocyanate (IPD).
I), hydrogenated diphenylmethane diisocyanate and the like can be used. As the chain extender, low molecular weight glycols such as ethylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol or piperazine, ethylenediamine, hexamethylenediamine, propylene-1,2-diamine, N- A primary or secondary aliphatic amine such as methyl-bis (3-aminopropyl) amine, 1,4-diaminocyclohexane, 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane is used. it can. Polytetramethylene ether-based polyurethane uses polytetramethylene ether glycol as a polyol component, and polypropylene ether-based polyurethane uses polypropylene ether glycol as a polyol component. Further, the polyester-ether polyurethane is a polyol component, for example, a polyester glycol comprising a glycol having 4 or more carbon atoms and a dicarboxylic acid, ethylene oxide, propylene oxide, or a polyol obtained by addition-polymerizing these, a glycol having 4 or more carbon atoms. A polyester-based polyurethane is obtained by reacting a hydroxyl compound having 6 or more carbon atoms as a polyol component with a dibasic acid by using a polyester glycol composed of carboxylic acid and dicarboxylic acid and a mixed polyol of polypropylene glycol or polypropylene / ethylene glycol. Polyester polyol, ε-caprolactone-based polyester polyol or polymethylvalerolactone-based polyester polyol is used. Examples of the diisocyanate compound and chain extender used in each of these polycarbonate-based, polytetramethylene ether-based, polypropylene ether-based, polyester-ether-based, and polyester-based polyurethanes include the same as those used in the polycarbonate-based polyurethane. . If necessary, various additives such as an antioxidant, a light stabilizer, an ultraviolet absorber and a hydrolysis inhibitor may be added to these polyurethanes.

The synthetic leather 1 of the present invention is provided with a surface treatment layer 5 for imparting surface lubricity to the surface of the surface skin layer 4. The surface-treated layer 5 is composed of polyurethane containing silicone oil and / or modified silicone oil, and polyurethane having a mixture of silicone diol and another polyol as a polyol component is used as the polyurethane.
Examples of the polyol used by mixing with the silicone diol include polycarbonate-based polyol, polytetramethylene ether-based polyol, polyester ether-based polyol, polyester-based polyol and the like.
The content of silicone diol in the polyol component is 5
If the amount is less than 50% by weight, no slipping effect is obtained, and if the amount exceeds 40% by weight, the sliding property is not further improved.
It is preferable to use it by mixing with the other polyol so that As the diisocyanate and chain extender constituting the polyurethane used in the surface treatment layer 5, the same diisocyanate and chain extender constituting the polyurethane used in the adhesive layer 3 and the skin layer 4 can be used.

Silicone oil contained in the surface treatment layer 5,
Examples of the modified silicone oil include dimethylpolysiloxane and alcohol-modified dimethylpolysiloxane. The content of these is preferably 1 to 50 parts by weight with respect to 100 parts by weight of polyurethane (solid content) constituting the surface treatment layer 5. The surface treatment layer 5 can be formed by performing gravure printing or the like using the polyurethane solution as described above, and the surface treatment layer 5 has a coating amount of the polyurethane resin solution of 0.1 to 5 g / m ² when dried. It is preferable to form by coating.

The synthetic leather 1 of the present invention has a skin layer 4 as shown in FIG.
An intermediate layer 6 of polyurethane may be provided between the adhesive layer 3 and the adhesive layer 3. The same polyurethane as that forming the skin layer 4 is used as the polyurethane forming the intermediate layer 6. The intermediate layer 6 may have a foamed structure. The intermediate layer 6 can be formed simultaneously with the skin layer 4 by a dry method. The thickness of the intermediate layer 6 is preferably 10 to 100 μ in the case of a non-foamed structure and 50 to 1000 μ in the case of a foamed structure. Such an intermediate layer 6 is provided between the skin layer 4 and the adhesive layer 3.
By providing, it is possible to obtain a synthetic leather that has excellent frictional strength and is rich in volume. Further, the synthetic leather 1 of the present invention can be used by impregnating the fiber base material 2 with polyurethane, and as shown in FIG. 3, a wet microporous layer of polyurethane is provided between the adhesive layer 3 and the fiber base material 2. 7 can also be provided. The wet microporous layer 7 is formed by coating the same water-soluble organic solvent solution of polyurethane as that used for the coating layer and then immersing it in water to dissolve and remove the water-soluble organic solvent in water to solidify the polyurethane. You can Further, although not particularly shown, a foam layer of polyurethane formed by a dry method may be provided in place of the wet microporous layer 7 of polyurethane. The thickness of the wet microporous layer 7 or the foam layer formed by the dry method is preferably 100 to 2000 μ,
When such a wet microporous layer 7 or a foam layer formed by a dry method is provided, the flexibility of the synthetic leather is improved and the texture is further improved.

Hereinafter, the present invention will be described in more detail with reference to specific examples.

Example 1 100% modulus was 50 kg / cm ^{2 on} the surface of release paper with a diaphragm.
Polycarbonate type polyurethane (Crisbon NY331 manufactured by Dainippon Ink and Chemicals, Inc.) has a thickness of 20μ when dried
Coated with a knife coater so that it will be dried with hot air at 100 ° C for 2 minutes to form a polyurethane film (skin layer),
Next, a urethane two-component adhesive (Crisbon TA-290 manufactured by Dainippon Ink and Chemicals, Inc.) consisting of polytetramethylene ether type polyurethane with 100% modulus of 15 kg / cm ² was dried on this film to a thickness of 30μ. It is coated with a knife coater so that this adhesive coated surface is Tetoron
The fiber base material made of rayon blended suede is superposed so that it is in contact with the raised surface of the fiber base material, and dried at 100 ° C for 5 minutes with hot air,
After maturing at 48 ° C. for 48 hours to solidify the adhesive, the release paper was peeled off to form a skin layer on the surface of the fiber base material with the adhesive layer interposed therebetween. Next, in an organic solvent solution of a polycarbonate-based polyurethane (Rezaroid SP-300 manufactured by Dainichiseika Kogyo Co., Ltd.) containing silicone diol as a polyol component, alcohol variable silicone (Toray Silicone Co., Ltd.) per 100 parts by weight of polyurethane (solid content) ): SF-8427) and 15 parts by weight of dimethylpolysiloxane-polyoxyalkylene copolymer (SH-28PA manufactured by Toray Silicone Co., Ltd.) were added, and the coating amount of this solution when dried was A synthetic leather was prepared by applying a gravure printing method to form a surface-treated layer at ² g / m ² .

The obtained synthetic leather has a slimy feel, has excellent surface lubricity that does not generate rubbing noise even when the surface is rubbed, has excellent hydrolysis resistance and light resistance, and has a natural feel and appearance. It was very similar to leather and was suitable for furniture, vehicles, etc.

Comparative Example 1 A synthetic leather having the same structure as in Example 1 except that the surface-treated layer did not contain alcohol-modified silicone and dimethylpolysiloxane-polyoxyalkylene copolymer was obtained by the same method.

Comparative Example 2 Polycarbonate polyurethane (manufactured by Dainichiseika Kogyo Co., Ltd .: Rezaroid Lu4003, containing no silicone diol as a polyol component) and the same alcohol-modified silicone and dimethylpolysiloxane-polyoxyalkylene copolymer as in Example 1 were used. Synthetic leather was obtained in the same manner as in Example 1 except that a surface treatment tank was formed by using a polyurethane solution to which was added the same amount.

Comparative Example 3 A polyurethane skin layer was formed on a fibrous substrate via an adhesive layer by the same method as in Example 1, and then the same alcohol-modified silicone and dimethylpolysiloxane-polyoxyalkylene copolymer as those used in Example 1 were used. A solution obtained by simply dissolving the polymer in toluene was applied and dried to obtain a synthetic leather.

The amounts of the alcohol-modified silicone and dimethylpolysiloxane-polyoxyalkylene copolymer attached to the surface of the skin layer were the same as those of the alcohol-modified silicone and dimethylpolysiloxane-polyoxyalkylene contained in the surface treatment layer of Example 1. It was made to be the same as the amount of copolymer.

Table 1 shows the results of testing the synthetic leather obtained in Example 1 and Comparative Examples 1 to 3 for the effect of preventing scratching noise under the following conditions.

Scratch noise prevention effect test conditions Using a Gakushin type friction fastness tester, 20
After rubbing each time shown in Table 1 with a cotton cloth under a load of 0 g, the surfaces of the synthetic leathers were rubbed together to check whether or not a scratching sound was generated.

○: No scratching sound was generated.

Δ: A slight scratching sound was generated.

× ... Scratching noise is severe.

Was evaluated.

[Effects of the Invention] As described above, the synthetic leather of the present invention is formed of polyurethane containing silicone oil and / or modified silicone oil on the surface of the polyurethane skin layer and containing silicone diol in the polyol component. It has excellent surface lubricity by having a surface treatment layer, there is no risk of generating unpleasant scratching noise when the surface is rubbed like conventional synthetic leather, and the surface lubricity is long lasting. The effect of preventing specific scratching noise is obtained.

[Brief description of the drawings]

The drawings show examples of the present invention, FIG. 1 is a longitudinal sectional view showing one embodiment of the synthetic leather of the present invention, and FIGS. 2 and 3 are vertical cross-sections showing other embodiments of the synthetic leather of the present invention. It is a side view. 1 ... Synthetic leather, 4 ... Skin layer, 5 ... Surface treatment layer

Claims (1)

(57) [Claims] 1. A synthetic leather having a surface treatment layer containing polyurethane oil containing a silicone oil and / or a modified silicone oil and containing a silicone diol in a polyol component on the surface of the polyurethane skin layer.