JPS59150184A - Production of leather-like sheet with good feeling - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a method for producing a leather-like sheet that has a natural leather-like surface morphology, a flexible feel and drapability, and excellent shape stability.

[Prior art]

Conventional methods for manufacturing leather-like sheets include the so-called dry method, in which a film layer is formed on a release paper having an uneven pattern, and then adhered onto a substrate; After applying and processing by wet method,
Two methods are commonly used: creating a surface layer and embossing it with an embossing roll that gives the surface an uneven pattern. Among these, the former dry method is the most commonly used method at present, and involves gluing a grain layer onto the surface of a woven fabric, or creating a grain layer on the surface of a raised fabric using a similar method. Furthermore, there are a large number of products on the market, such as those with a silver layer on the surface of non-woven fabric, but the appearance and texture of the products obtained by this treatment are very artificial. Currently, only cheap products are available.

The simplest thing that can be obtained by this dry method is a knitted fabric with a grain layer made of a film layer on the surface, but in order to soften the texture, the grain layer can be made thinner. Because the ground structure is visible, its commercial value is reduced.

On the other hand, in order to make the texture of the knitted fabric inconspicuous, there are those in which a grain layer is created on the surface of the raised woven fabric, and there are also those in which a foam layer is provided on the surface of the knitted fabric and then a grain layer is created on the surface. However, it is difficult to completely eliminate the texture of knitted fabrics, and moreover, it is difficult to obtain citrepure properties due to the thickness of the fabric, and it is difficult to obtain a material that has the drapability and soft texture of natural leather. difficult.

This type of leather sheet can be used as a flooring material in various types of fineness and fineness.
Alternatively, by appropriately selecting the form density of the flooring material, the type of polymer, the concentration of the solution, etc., it is possible to manufacture from a hard material to a somewhat soft material. However, by simply selecting these conditions, it is impossible to obtain a leather-like sheetra that is extremely flexible and has a good texture that can be used for clothing, bags, and casual boots.

In order to obtain highly flexible products, products made using low-concentration solutions of flexible polyurethane elastomers with a large amount of soft segment components have inferior strength properties such as abrasion resistance9, and also have poor surface roughness. Easy to use. For this reason, many attempts have been made to use aliphatic 2-base hepta-acid esters, aliphatic esters, phthalic esters, glycol esters, and phosphoric esters as softeners; Even if this is achieved, there are still many drawbacks such as migration of the softener, changes in color or gloss, color transfer, and inhibition of adhesion, so it is still not possible to obtain a product that is satisfactory. be.

〔the purpose〕

The present invention overcomes the drawbacks of these conventional methods,
Furthermore, the present invention provides a leather-like sheet that has drapability, natural leather-like creases, and a soft texture.

〔composition〕

That is, the gist of the present invention is that when producing artificial leather having a surface coating layer made of a resin mainly composed of a polyurethane elastomer, an alkylene oxide-modified polysiloxane having a molecular weight of 500 to 20,000 is added to the polyurethane elastomer. 1-40 for solid content
The present invention is a method for producing a leather-like sheet with good performance, which includes forming a coating layer using a solution containing a certain amount of water.

The soft polyurethane used in the present invention may be polyether-based polyurethane, polyester-based polyurethane, or a mixture of two or more thereof, which are conventionally used for processing textile products.

Polyether polyurethane is produced by chain-extending a reaction product of at least one company's polyalkylene glycol and an organic isocyanate of at least one year old using a compound that has two active hydrogen atoms bonded to an amine atom. This is what was obtained. In addition, the polyester polyurethane is a polyester polyurethane in which a reaction product of a polynisdel obtained by reacting at least one alkylene glycol with at least 1+1 ester and at least one glaze of organic diisocyanate is bonded to an amine atom. It was obtained by chain extension using a compound that carries active hydrogen atoms. Examples of solvents for polyurethane include N-N dimethylformamide, toluene, ethyl acetate, methyl ethyl ketone, and mixtures thereof, and liquids that dissolve polyurethane and are compatible with the alkylene oxide-modified polysiloxane used in the present invention The alkylene oxide modified polysiloxane used in the present invention has a molecular weight of 500 to 20,000 and a silicon fraction of 60.
It is necessary that the amount of ethylene oxide in the alkylene oxide is at least 10 wt% or more. The reason for this is that molecular weights in the high molecular weight range exceeding 20.000 (5) are undesirable because they become paste-like or solid at room temperature and the solubility decreases; Although it has good properties, it has the ability to bleed the dye bonded to the fibers.

In general, those that cause a decrease in color fastness and cause skin disorders such as rash and itchiness on the face are undesirable. The composition ratio of ethylene oxide and propylene oxide is preferable because the amount of propylene oxide increases and in the high molecular weight region, the solubility decreases and uniform adhesion becomes difficult, and also from the work point of view. do not have.

Regarding silicon content, the balance with the amount of alkylene oxide is extremely important, and the results of various studies have shown that products with a silicon content of 60 wt % or less are superior in product performance. Next, the amount of these alkylene oxide-modified polysiloxanes to be used is suitably 1 to 40 parts by weight fA', and more preferably 5 to 30 parts by weight, based on the solid content of the polyurethane. If the amount used is less than 1 V, it will be difficult to obtain the desired flexibility, but if it exceeds 40 parts, the stability of the solution will be poor, and the performance of the resulting film will be poor. It is difficult to use as it deteriorates significantly.

Generally, the method for creating a silver surface layer is to use a soft polyurethane resin as the main material, and to this, a solution consisting of a pigment, a solvent, and the above-mentioned softener is added directly onto the substrate using a knife coater or a roll coater. You can apply it by coating, or apply it on release paper using a knife coater, etc., and then apply it to the substrate using an adhesive! There is a way to make it ll@.

In either case, the thickness of the film is suitably 10 to 40 .mu.m; if the thickness of the film layer is less than 10 .mu.m, the elasticity of the film is weak and there are problems in terms of wear. If it exceeds 40μ, the urethane elasticity will be strong, resulting in poor drapeability and a sense of unity. However, even if the film layer is between 10 and 40μ, the drape properties of the base fabric are large, and the film has a large influence on soft textured fabrics, so the drape properties of the base fabric itself are Often lowered.

The inventors of the present invention have found that by using the above-mentioned alkylene oxide-modified polysiloxane, the present inventors can create a coating layer on a substrate that has great drapability and a soft texture. A leather-like sheet with an appearance similar to natural leather was obtained.

Hereinafter, the present invention will be explained in detail with reference to examples.

In the examples, "part" or "part" simply refers to % by weight or weight. The evaluation method used in the examples is as follows.

1. Abrasion resistance (J-tech 5L-1021 rug test) J-tech 5
A wear test was conducted using a taper type abrasion tester used in L-1021 Rug Test Method 5-12. Base: Worn ring O
The load applied to 5002 using 8-10i was determined by rotational friction at approximately 70-rpm, and the change in appearance after a certain number of rotations.

(Good) ○〉△〉×(Poor) 2 Rub-in test Using a Scotto-type kneading tester, the grip interval was 30+
After the two test pieces are sandwiched between each other with their surfaces inward, the distance between them is gradually narrowed until the surface of the test piece is touched lightly and the distance is narrowed until the load becomes 1 to 9.

The kneading speed was set to 120 times per minute, and after the kneading operation was performed a specified number of times, the peeling state between the silver surface layer and the base layer and the presence of any other abnormalities were checked and semi-finished in the same manner as in 1.

3. Evaluation was performed on the samples after dry cleaning using a dry cleaning bar crane a predetermined number of times.

4. Place double-sided art paper on top of the colored silver surface layer of the dye-transferable artificial leather product,
180? After applying a pressure of 7 cm2 and leaving it for 20 hours in an atmosphere of 60°C and 90% humidity, a sample was taken (1) and the state of color transfer to the art paper was determined.1. Ta.

[Example-1] A solution of a soft polyurethane resin solution containing the auxiliary agent shown below was applied to the release thread using a doctor knife so that the dry film layer had a thickness of 20μ, and this was dried at 100°C for 2 minutes. .

The 100 thimodules strength and elongation of the resin film thus obtained were measured.

Composition *The following alkylene oxide-modified polysiloxane was used: Molecule i7,000 Silicon content: 22wt% As seen in the above results, each type of silicone compound was added to the polyurethane resin solution. As a result of comparison, it was found that the material to which Elj, an alkylene oxide-modified polysiloxane, as an auxiliary agent in the method of the present invention was added, was much softer than the material to which other additives were added, and had a texture similar to that of urethane. It had excellent softness with little elasticity.

[Example 2] A copolymer of 92% acrylonitrile and vinyl acetate was dissolved in total dimethylacetamide and subjected to wet spinning.

It was then drawn in boiling water to obtain a pole IV+11+ fiber tow with an average fineness of 0.1 denier and a total fineness of 4,200 denier.

This tow was cut into three pieces, all of the short fibers were disintegrated uniformly into single fibers using a conventional disintegrating machine, and monthly 259
I took a 7m2 web.

Separately, polyester filament 75d/36f with a potential shrinkage rate of 40 cm in boiling water is 150 cm/
I took a single jersey with a '540 loop.

The above web was laminated on this polyester knitted fabric, and this was placed on a 90-mesh wire mesh.

Next, using a multi-hole nozzle with 0.15 ramφ and 1 cylinder pitch from [web elevation], high pressure columnar flow treatment '1 +, OK
q7crn2G, 30 K9/L: Continuously injected into rn2G and 30 at a pressure of 97 cm2G.

The obtained sheet was turned over, two sheets of the above web were laminated thereon, and liquid flow treatment was performed under the same conditions.

This sheet was shrunk in boiling water (area shrinkage factor: 40), dried, heat set at 150° C., and dyed to obtain a sheet structure.

The obtained sheet characteristic values were as follows.

Tensile strength shuttle 9. OKp/cm Weft 5.1 to 97α Ultrafine fiber/base fabric (weight 1 ratio) = 0.9.3 stitches
2 2 5 97m2 cloth
The obtained sheet structure has a thickness of 0.62mm, and both sides of the base fabric are covered with ultrafine fibers, and one side is napped (side A), and the other side is in the 11 state (side B), with the napping ≦ face down. It had excellent reeds, drapability, and flexibility.

A two-component urethane resin was applied to the above substrate using the following polyurethane resin solutions A to F on a film formed on a release paper using the treatment of Practical Example-1 at a wet weight of 60 to 80 ln/ln 2.
After coating with a doctor knife, the adhesive was immediately bonded to the three sides of the substrate at a pressure of 1 to 1/an2.

Next, drying at 80°C for 3 minutes and further at 120°C for 3 minutes,
Heat treatment was performed. Thereafter, it was left to stand for 3 days and the release paper was peeled off. This product was completely treated with a cationic softener and a silicone softener.

The obtained product had the following characteristics.

Judgment (艮) ◎〉○〉△〉×(Poor) As seen in the above results, B, which is an example of the present invention, is superior to the control product in all aspects such as texture, performance, and color migration. It can be seen that In addition, the finished product has excellent drapability, good grain condition, and the back side is made of raised microfibers, making it an expensive product with a texture that closely resembles a natural silver surface product. Met.

Claims (1)

[Scope of Claims] When producing artificial leather having a surface layer made of a resin mainly composed of polyurethane elastomer, an alkylene oxide modified polyurethane having an n i of 500 to 20,000 is added to the polyurethane elastomer solution. 1 to 4 siloxane per solid content of polyurethane
A 1M method for producing a leather-like sheet with a good texture, in which a covering layer is formed using a solution containing 0 parts by weight.