JP2801252B2 - Manufacturing method of sheet material - Google Patents

Description

The present invention relates to a method for producing a sheet-like material.

The sheet-like material produced by the present invention has a sponge structure exhibiting good smoothness and a soft feeling, has excellent hydrolysis resistance, and is suitable for a surface layer of a leather-like sheet.

[Conventional technology]

BACKGROUND ART Conventionally, it is known that a solution of a polymer mainly composed of a polyurethane elastomer is applied to a substrate and solidified, and the formed coating layer is peeled from the substrate to form a porous sheet.

1,9-nonanediol and / or 2-methyl-1,8
A polyester polyurethane elastomer obtained by reacting a polyester diol (hereinafter abbreviated as PNOA) obtained by the condensation polymerization of octanediol and a dicarboxylic acid, an organic diisocyanate and a complex elongation agent into synthetic leather. It has been reported that it is used as a coating agent impregnating agent or hand controlling agent for artificial leather (see JP-A-61-185520 and JP-A-62-22817).

[Problems to be solved by the invention]

Perhaps because the PNOA-based polyurethane has a higher solidification rate than the conventional polyester-based polyurethane, when the conventional method is performed using the PNOA-based polyurethane, the sponge structure has a crushed sponge structure and a sheet with a poorly smooth surface. Only things are obtained.

In the case of producing a leather-like sheet, a multicomponent fiber obtained by spinning at least two kinds of polymers is usually used as a base fiber, and this fiber is impregnated with a polyurethane elastomer and coagulated. An operation of changing the fiber form by removing at least one component of the above by a solvent treatment or a decomposing agent treatment is performed. At this time, the sponge structure formed by the polyurethane elastomer is often deformed by the action of the treating agent.

An object of the present invention is to provide a method for producing a porous sheet having a sponge structure exhibiting good smoothness and a soft touch.

[Means for solving the problem]

According to the present invention, the above object is achieved by (a) condensation polymerization of a diol having 1,9-nonanediol and / or 2-methyl-1,8-octanediol as a main component and a dicarboxylic acid. Polyester diol having a number average molecular weight of 500 to 4,000, a polyurethane elastomer obtained by reacting an organic diisocyanate and a chain extender,
(B) a polyether-modified silicone oil, (c) a polyoxyethylene-polyoxypropylene block copolymer, and (d) a solvent for the polyurethane elastomer, wherein the total amount of the components (b) and (c) is ( (a) 0.5 to 50% by weight based on the component, and (b)
A polyurethane elastomer composition solution in which the weight ratio of the component to the component (c) is 1/20 to 5/1 is applied to a base material, coagulated with a non-solvent of the polyurethane elastomer, and then formed on the base material. This is attained by providing a method for producing a sheet-like material characterized in that a coating layer is peeled from a substrate.

The polyester diol is produced by subjecting a diol mainly composed of 1,9-nonanediol and / or 2-methyl-1,8-octanediol to condensation polymerization with a dicarboxylic acid according to a conventional method. . Raw material diols include, for example, ethylene glycol, propylene glycol, butanediol, hexanediol, 3-methyl-
It may contain a small amount of a diol such as 1,5-pentanediol, 1,4-cyclohexanediol, or xylene glycol. Examples of dicarboxylic acids include adipic acid,
Aliphatic dicarboxylic acids such as pimelic acid, suberic acid, azelaic acid, and sebacic acid; aromatic dicarboxylic acids such as isophthalic acid and terephthalic acid; and one or a combination of two or more of these. used. A polyester diol having a number average molecular weight in the range of 500 to 4,000 determined from the hydroxyl value is used. The number average molecular weight is preferably in the range of 900 to 3,000.

The polyurethane elastomer used in the present invention is produced by reacting the polyester diol, the organic diisocyanate, and the chain extender at a desired ratio according to a conventional method. Examples of the organic diisocyanate include aromatic diisocyanates such as 4,4'-diphenylmethane diisocyanate, tolylene diisocyanate, phenylene diisocyanate, and xylylene diisocyanate; hexamethylene diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, hydrogenated Examples thereof include aliphatic or alicyclic diisocyanates such as tolylene diisocyanate and hydrogenated xylylene diisocyanate, and compounds having two active hydrogen atoms as chain extenders, for example, ethylene glycol, propylene glycol, butanediol, hexanediol , 3-methyl-1,5-pentanediol, 1,4
Diols such as cyclohexanediol and xylene glycol; diamines such as ethylenediamine, propyleneamine, xylylenediamine, isophoronediamine, piperazine, phenylenediamine, tolylenediamine and isophoronediamine; hydrazine; hydrazides such as adipic dihydrazide and isophthalic dihydrazide. And the like. These organic diisocyanates and complex extenders are used alone or in combination of two or more.

It is desirable to use a polyurethane elastomer having a solution viscosity of a 10% by weight solution of dimethylformamide at 30 ° C. of at least 1 poise, preferably 2 to 10 poise. When a solution having a low solution viscosity is used, the strength of the sponge structure of the obtained sheet-like material is not sufficient, or the bending fatigue resistance is not sufficient. On the other hand, a polyurethane elastomer having a solution viscosity that is too high not only has poor processability, but also makes it difficult to impart a sponge structure with good uniformity to a sheet-like material. Further, another polymer may be mixed in the polyurethane elastomer at a ratio of 40% by weight or less. When a polyethylene ether polyurethane elastomer obtained by polymerizing polyethylene ether glycol as a diol component as the polymer is mixed with the above polyurethane elastomer at less than 10% by weight, the polyethylene ether polyurethane elastomer is mixed in a coagulating liquid containing a non-solvent, particularly water. When coagulating the polyurethane elastomer, not only uniform coagulation can be carried out, but also the dyeing properties of the polyurethane elastomer are improved, and a soft and moist feeling sheet-like material is obtained.

Examples of the solvent for the polyurethane elastomer include dimethylformamide, dimethylacetamide, N-methylpyrrolidone, dimethylsulfoxide and the like, and dimethylformamide is preferably used.

The polyurethane elastomer composition liquid used in the present invention comprises a polyether-modified silicone oil (hereinafter abbreviated as component (b)), which is a copolymer of siloxane and polyoxyalkylene, and a polyoxyethylene-polyoxypropylene block copolymer. (Hereinafter, abbreviated as component (c)) at a specific ratio,
It is necessary for providing a stable sponge structure to the sheet-like material. The components (b) and (c) are in a weight ratio of 1/20 to 5 /
It is in the range of 1. When the proportion of the component (b) is higher than this, or when the proportion of the component (c) is higher, a porous sheet having good smoothness cannot be obtained. (B) component and (c)
The components are preferably in the range of 1/10 to 2/1 by weight. As the component (b), for example, Chris Bon Assister-SD
-7 (manufactured by Dainippon Ink and Chemicals, Inc.), and the component (c) includes, for example, Crisbon Assister SD-14 (manufactured by Dainippon Ink and Chemicals, Inc.). The total amount of the components (b) and (c) is 0.5 to 50% by weight based on the polyurethane elastomer. If the total amount is less than 0.5% by weight, the sheet will not be porous with good sponge structure or uniform sponge structure. On the other hand, when the total amount is more than 50% by weight, the diaphragm in the sponge structure of the sheet-like material becomes thin, and the diaphragm becomes too porous, so that the sheet-like material has mechanical strength and swelling resistance. It will be low.

As the substrate (or support) on which the polyurethane elastomer composition liquid is applied, a sheet, a plate-like material, a fiber structure, or the like made of a material that is not affected by the solvent of the polyurethane elastomer is used. For example, a polyethylene sheet, a polypropylene sheet, a polyester sheet , Polyamide sheets, synthetic rubber sheets, fabrics made of organic fibers or inorganic fibers, or fabrics obtained by applying a silicone resin, a fluorine resin or the like to such fabrics, sheets or plate-like materials such as glass plates; natural fibers, recycled Woven fabric using fibers, synthetic fibers obtained by a normal spinning method of a single component, multicomponent fibers obtained by discharging and spinning at least two kinds of polymers having different physical or chemical properties from one nozzle, Fiber structures such as knitted fabrics, fibrous raised woven fabrics, and fiber entangled nonwoven fabrics, Fiber structure which contains a body and the like. When producing a porous sheet-like material for the surface coating layer of a leather-like sheet, a fibrous structure composed of multicomponent fibers as a base material or a polymer mainly composed of a polyurethane elastomer in the fibrous structure is porous or It is particularly preferable to use those contained in a non-porous state. When such a substrate is used, a sheet having flexibility and good secondary workability can be obtained.

The polyurethane elastomer composition liquid is coagulated by the non-solvent of the polyurethane elastomer. As the non-solvent for the polyurethane elastomer, water or an aqueous solution of the above-mentioned solvent for the polyurethane elastomer is used. As the non-solvent, it is preferable to use an aqueous solution of about 20 to 40% of dimethylformamide. The solidification temperature affects the sponge structure formed in the sheet. If the coagulation temperature is high,
Since the whole is slowly solidified, a fine and uniform sponge structure is obtained. On the other hand, when the solidification temperature is low, a dense skin layer is formed on the surface, and the inside is loosely solidified to form a huge uniform sponge structure. To form a preferable sponge structure, the solidification temperature may be selected in the range of about 25 to 75 ° C. The polyurethane elastomer coating layer on the substrate obtained by coagulation is separated from the substrate, washed with water, and dried to obtain a porous sheet having a surface with good smoothness.

The sheet-like material obtained by the present invention has a safe sponge structure and has good surface smoothness and flexibility, so the sheet-like material is directly subjected to coloring treatment, embossing treatment, pattern printing, etc. After finishing, for example, wall coverings,
It can be used as an interior decoration material or for decoration of various articles. Further, the sheet-like material obtained in the present invention can be adhered to a flexible fibrous base material and finished as a grain surface layer of a leather-like sheet.

〔Example〕

Hereinafter, the present invention will be described specifically with reference to Examples. In addition,
Parts and% in the examples are parts by weight and% by weight unless otherwise specified.

Example 1 Polyester diol having a number average molecular weight of 2,000 obtained by subjecting a mixture of 1,9-nonanediol and 2-methyl-1,8-octanediol (molar ratio 50/50) to condensation polymerization with adipic acid, 4,4'-diphenylmethane diisocyanate and 1,4-butanediol (molar ratio 1: 6: 5, soft segment ratio 50.6%, nitrogen content based on isocyanate groups)
4.3%) was reacted to obtain a 13% dimethylformamide solution (10% dimethylformamide solution having a viscosity of 3 poise at 30 ° C.). The solution was added to Chrisbon Aster SD-7 (as described above, (( b) component) and Crisbon Assister SD-14
(As described above, the mixture of the component (c)) (the component (b) /
(Component (c) (weight ratio) = 1/2) was added to the polyurethane elastomer in an amount of 20%, and carbon black as a coloring material was added in an amount of 20% to the polyurethane elastomer to prepare a polyurethane elastomer composition liquid.

This polyurethane elastomer composition solution was applied on a polyethylene sheet substrate in a flow rate of 500 g / m ² (a polyurethane elastomer amount of 62 g / m ² ) by a casting method, and then the substrate was coated with a 25% aqueous solution of dimethylformamide (liquid). (Temperature of 40 ° C.) to solidify. The obtained polyurethane elastomer coating layer was peeled off from the substrate, desolvated and washed in hot water at 80 ° C., and dried to obtain a sheet. The obtained sheet-like material has a basis weight of 70 g / m ² , a thickness of 0.33 mm, an apparent density of 0.23 g / cm ³ , has a sponge structure having long pores almost perpendicular to the surface, and has a smooth surface. It was a flexible one.

After bonding the surface of the porous sheet in contact with the base material to the nylon tricot with a cross-linked polyurethane adhesive, the surface was polished with sandpaper for about 0.04 to 0.05 mm to expose the internal porosity, A suede-like sheet having a beautiful appearance and formed by uniform pores was obtained. This sheet was soft and drapable and could be used as a black clothing material. In addition, the sheet-shaped material was free from any abnormality in a hydrolysis resistance test using a jangle tester in an atmosphere at a humidity of 95% and a temperature of 70 ° C. for 6 weeks, and was good without impairing the surface smoothness.

Comparative Example 1 The same as Example 1 except that the additive amount of the additive mixture of Chris Bon Assister SD-7 and Chris Bon Assister SD-14 was 0.4% based on the polyurethane elastomer. The sheet-like material obtained by performing the processing operation described in
g / m ² , thickness 0.19 mm, apparent density 0.45 g / cm ³ , irregularities are formed on the surface like fine wrinkles, and the sponge structure is formed with pores of non-uniform shape It was. An attempt was made to prepare a suede-like sheet by treating this sheet in the same manner as in Example 1. However, the resulting sheet had a poor appearance and a hard feel.

Also, when a polyurethane elastomer composition liquid in which the amount of the additive mixture was more than 50% based on the polyurethane elastomer was used, although a flexible porous sheet-like product was obtained, the pores were large and the space between the pores was large. Since the partition walls were thin, the sheet-like material was easily peeled into two sheets between the surface layer and the back layer.

Examples 2 to 4 and Comparative Examples 2 and 3 In a 13% dimethylformamide solution of the same polyurethane elastomer obtained in Example 1, an additive mixture having the weight ratio shown in Table 1 was added to the polyurethane elastomer.
Each polyurethane elastomer composition liquid was prepared by adding 20%.

These polyurethane elastomer composition liquids are applied on a polyethylene sheet substrate in an amount of 600 g / m ^{2 in} a liquid amount, and then the substrate is dimethylformamide 25% aqueous solution (liquid temperature 40
C) and solidified. The polyurethane elastomer coating layer formed on the substrate was peeled off from the substrate, desolvated and washed in hot water at 80 ° C., and dried to obtain a sheet. Table 2 shows the sponge state, appearance, and the like of the obtained sheet.

These porous sheet-like materials were bonded to a 1.2-mm-thick fibrous base material obtained by incorporating a polyester-based polyurethane into a nylon-6 ultrafine fiber bundle-like fiber entangled nonwoven fabric prepared in advance by a solvent bonding method. After adhesion, a colorant was applied to the surface and embossed to obtain a leather-like sheet with silver finish. The sheet-like material obtained using the porous sheet-like material of the example is a leather-like sheet-like material having a good embossed pattern, generating a large number of thin and long folded wrinkles, and having an apparent weight. On the other hand, the sheet material obtained using the porous sheet material of the comparative example had poor embossing pattern imparting properties and poor folding wrinkles.

Example 5 and Comparative Examples 4 and 5 A number average obtained by condensation polymerization of a mixture of 1,9-nonanediol and 2-methyl-1,8-octanediol (molar ratio 30/70) with adipic acid. Polyurethane elastomer obtained by reacting polyester diol having a molecular weight of 1,500, 4,4'-diphenylmethane diisocyanate and ethylene glycol (molar ratio 1: 3.7: 2.7, soft segment ratio 57.8%, nitrogen content based on isocyanate group 4.0%) (10% dimethylformamide solution at 30 ° C. with a viscosity of 3 poise) was used as a 13% dimethylformamide solution, and the solution was added to Chrisbon Aster SD-7 (component (b) as described above) and Chrisbon Assister SD-14.
(As described above, the mixture of the component (c)) (the component (b) /
(C) Component (weight ratio) = 8/10) was added to polyurethane elastomer at 20% to prepare a polyurethane elastomer composition liquid. This polyurethane elastomer composition solution is applied to a substrate under the same conditions as in Example 2, coagulated, the polyurethane elastomer coating layer formed on the substrate is peeled off from the substrate, desolventized, washed, and dried to obtain a sheet. A product was obtained.

For comparison, a polyurethane elastomer obtained by using a polyester diol having a number average molecular weight of 450 as the polyurethane elastomer in the above method (molar ratio 1: 1.
5: 0.5, soft segment ratio 61.5%, nitrogen content based on isocyanate group 4.0%) or polyurethane elastomer obtained by using a polyesterdiol with a number average molecular weight of 4,050 (molar ratio 1: 10.5: 9.5, soft segment ratio 55.7)
%, The amount of nitrogen based on isocyanate groups is 4.0%) to obtain a sheet-like material by the same operation. Table 3 shows the sponge state, appearance, and the like of the obtained sheet.

Reference Example 1 A polyurethane elastomer composition liquid was prepared in the same manner as in Example 1 except that titanium oxide was added as a coloring material in place of carbon black by 2% to the polyurethane elastomer. This polyurethane elastomer composition solution was applied on a 1.2 mm thick fibrous base material obtained by adding a polyester-based polyurethane to a previously prepared nylon-6 ultrafine fiber bundle fiber entangled nonwoven fabric in a liquid amount of 850 g / applying a quantity of m ^2, and then solidified by immersing the substrate in dimethylformamide 30% aqueous solution (solution temperature 40 ° C.). Then 80
The solvent was removed, washed and dried in hot water at ℃ to obtain a porous sheet material in which a porous polyurethane elastomer was coated on a fibrous base material. The surface of the porous sheet material had good smoothness.

A white ink was prepared using the same polyurethane elastomer as that obtained in Example 1 as a base material and a pigment mainly containing titanium oxide. Using the white ink, the above porous sheet is colored with a 140-mesh gravure roll, dried, and then embossed and rubbed with a rough ground pattern (cowhide) to form a silver-finished sheet. I got something. This material had good appearance, texture, and wrinkles, good bending fatigue resistance, and was suitable as a material for men's shoes and sports shoes.

〔The invention's effect〕

ADVANTAGE OF THE INVENTION According to this invention, the porous sheet-like material which has good smoothness, softness, and excellent drape property, and has a stable sponge structure excellent in bending resistance and processing decomposition resistance is manufactured. Further, the manufactured sheet material has excellent weather resistance and low-temperature characteristics. The silvered leather-like sheet obtained from this sheet-like material has good appearance such as a wrinkled form and embossed-type fixability, and the suede-like sheet-like material has good napped properties. In addition, these sheet materials are excellent in secondary workability, for example, cutting workability, sewing workability, plowing, embossability, and the like.

Claims (1)

(57) [Claims] (A) a number average molecular weight of from 500 to 500 obtained by condensation polymerization of a diol having 1,9-nonanediol and / or 2-methyl-1,8-octanediol as a main component and a dicarboxylic acid; Polyurethane elastomer obtained by reacting 4,000 polyester diol, organic diisocyanate and chain extender, (b) polyether-modified silicone oil, (c) polyoxyethylene-polyoxypropylene block copolymer, and (d) solvent for the polyurethane elastomer And the total amount of component (b) and component (c) is 0.5 to 50 with respect to component (a).
% By weight, and the weight ratio of the component (b) to the component (c) is
A polyurethane elastomer composition liquid that is 1/20 to 5/1 is coated on a substrate, coagulated with a non-solvent of the polyurethane elastomer, and then the polyurethane elastomer coating layer formed on the substrate is peeled off from the substrate. Characteristic sheet-like manufacturing method.