WO2018186142A1 - Methods for producing porous body, glove and synthetic leather - Google Patents

Abstract

The present invention provides a method for producing a porous body, the method being characterized by coagulating an aqueous urethane resin composition using an aqueous solution of a metal-free coagulating agent. The present invention also provides a method for producing a glove having a coagulated film of the aqueous urethane resin composition, the method being characterized in that the coagulated film is obtained by immersing the aqueous urethane resin composition in an aqueous solution of a metal-free coagulating agent. The present invention also provides a method for producing a synthetic leather, the method being characterized by coating an aqueous urethane resin composition on a base fabric and then immersing the same in an aqueous solution of a metal-free coagulating agent. It is preferable to use an ammonium salt of an inorganic acid as the metal-free coagulating agent in order to achieve far better texture. The problem to be solved by the present invention is to provide a method for producing a glove having an excellent texture.

Description

Porous body, glove, and synthetic leather manufacturing method

The present invention relates to a method for producing a porous body, gloves, and synthetic leather.

Compared to conventional organic solvent-based urethane resin compositions, aqueous urethane resin compositions in which urethane resins are dispersed in an aqueous medium can reduce the environmental impact, so synthetic leather, coating agents, adhesives, gloves, etc. are manufactured. In recent years, it has begun to be used favorably as a material to be used.

The synthetic leather is generally composed of a fibrous base material such as a nonwoven fabric, an intermediate layer, and a skin layer, and the fibrous base material is intended to improve the flex resistance and texture of the synthetic leather. A fiber base material such as nonwoven fabric impregnated with an aqueous urethane resin composition and heat-coagulated (impregnated layer) is used.

As the aqueous urethane resin composition for the impregnation layer, for example, an aqueous urethane resin composition containing a urethane resin having a carboxyl group and / or a sulfonic acid group, a heat-sensitive coagulant, and an aqueous medium is disclosed (for example, , See Patent Document 1).

However, in the coagulation of aqueous urethane resin composition by heat-sensitive coagulation, the viscosity of the urethane resin mixture is once lowered by heating, the coating solution is absorbed by the fiber base material, and the resin adheres to the fiber intersection by capillary action. It has been pointed out that the synthetic leather obtained has a poor texture, is inferior in flexibility and flexibility, and is easily damaged because the resin restrains the fibers.

In addition, in glove applications, it has been studied to form a film made of a composition blended with aqueous polyurethane for the purpose of modifying natural rubber or synthetic rubber latex on the surface of a fiber-based glove (for example, Patent Document 2). See).

However, in such a case, when the composition containing the aqueous polyurethane is processed into a fiber base material or the like, the urethane resin component is unevenly distributed on the surface of the fiber base material, resulting in a problem that the texture becomes hard.

Japanese Patent Laying-Open No. 2015-7172 JP-A-8-209415

The problem to be solved by the present invention is to provide a production method in which an organic solvent is not used and a porous body having an excellent texture can be obtained.

The present invention provides a method for producing a porous body, characterized in that an aqueous urethane resin composition is coagulated with an aqueous nonmetallic coagulant solution. The present invention is also a method for producing a glove having a solidified film of a water-based urethane resin composition, wherein the solidified film immerses the water-based urethane resin composition in a non-metal coagulant aqueous solution. The manufacturing method of this is provided. Furthermore, this invention provides the manufacturing method of the synthetic leather characterized by apply | coating an aqueous | water-based urethane-resin composition to a base fabric, and making it immersed in a nonmetallic coagulant aqueous solution.

According to the production method of the present invention, a porous body excellent in texture can be obtained without using an organic solvent. Moreover, since it does not contain metal ions as a coagulant, it does not cause rusting or deterioration of the production apparatus when producing a coagulated product. Therefore, the porous body obtained by the production method of the present invention can be suitably used for production of gloves and synthetic leather.

The electron micrograph of the cross-sectional view of the porous body obtained in Example 4 is shown (magnification 200 times).

The method for producing a porous body according to the present invention coagulates an aqueous urethane resin composition with a nonmetallic coagulant aqueous solution.

In the present invention, it is essential to use a non-metal coagulant aqueous solution as the coagulant. In the present invention, by using a nonmetallic coagulant, the aqueous urethane resin composition can be thickened, and a porous body having an excellent texture can be obtained. Moreover, since the coagulation rate is improved by increasing the concentration of the coagulant, a porous body having a better texture can be obtained.

The temperature of the non-metal coagulant aqueous solution is preferably in the range of 10 to 100 ° C., more preferably in the range of 20 to 80 ° C., because a porous body can be obtained more easily. In the present invention, “porous body” refers to a material having a large number of pores.

Examples of the nonmetallic coagulant include ammonium chloride, tetramethylammonium chloride, tetraethylammonium chloride, tetrapropylammonium chloride, tetrabutylammonium chloride, tetrahexylammonium chloride, tetraoctylammonium chloride, tetraphenylammonium chloride, and triethylmethyl chloride. Ammonium, triethylhexylammonium chloride, trioctylmethylammonium chloride, trioctylbutylammonium chloride, trioctylbenzylammonium chloride, trimethylbenzylammonium chloride, tributylbenzylammonium chloride, triphenylisobutylammonium chloride, triphenylbenzylammonium chloride, ammonium bromide , Tetramethylammonium bromide, tetraethyl bromide Ammonium, tetrapropylammonium bromide, tetrabutylammonium bromide, tetrahexylammonium bromide, tetraoctylammonium bromide, tetraphenylammonium bromide, triethylmethylammonium bromide, triethylhexylammonium bromide, trioctylmethylammonium bromide , Trioctylbutylammonium bromide, trioctylbenzylammonium bromide, trimethylbenzylammonium bromide, tributylbenzylammonium bromide, triphenylisobutylammonium bromide, triphenylbenzylammonium bromide, ammonium iodide, tetramethylammonium iodide Tetraethylammonium iodide, Tetrapropylammonium iodide, Tetrabutylammonium iodide, Tetrahedium iodide Silammonium, tetraoctylammonium iodide, tetraphenylammonium iodide, triethylmethylammonium iodide, triethylhexylammonium iodide, trioctylmethylammonium iodide, trioctylbutylammonium iodide, trioctylbenzylammonium iodide, iodide Ammonium halides such as trimethylbenzylammonium iodide, tributylbenzylammonium iodide, triphenylisobutylammonium iodide, triphenylbenzylammonium iodide; ammonium hydrochloride, ammonium phosphate, ammonium borate, ammonium hydrofluoride, ammonium sulfate, ammonium nitrate, Inorganic acid ammonium such as ammonium silicate and ammonium phosphate; ammonium formate, acetic acid ammonium Organic acid ammonium such as ammonium, ammonium propionate, ammonium malate, ammonium sulfamate; tetraphenylphosphonium chloride, tetraphenylphosphonium iodide, tetramethylphosphonium bromide, tetrabutylphosphonium chloride, tetrabutylphosphonium bromide, tetraiodide An inorganic acid phosphonium such as butylphosphonium; an organic acid phosphonium such as tetrabutylphosphonium acetate can be used. These nonmetallic coagulants may be used alone or in combination of two or more.

As the non-metal coagulant, among the above-mentioned, the thickening and coagulation speed of the aqueous urethane resin composition is fast, it is possible to suppress the fiber adhesion / restraint of the resin due to the capillary phenomenon, and a more excellent texture is obtained. Inorganic acid ammonium is preferably used, and ammonium sulfate is more preferable.

As the water used for the non-metal coagulant aqueous solution, for example, ion exchange water, distilled water, tap water, or the like can be used. These waters may be used alone or in combination of two or more.

The content of the nonmetallic coagulant is preferably in the range of 1 to 60% by mass, more preferably in the range of 2 to 55% by mass, and more preferably in the range of 25 to 50% by mass in the nonmetallic coagulant aqueous solution. The range of is more preferable.

As the aqueous urethane resin composition that can be used in the present invention, for example, those containing an aqueous urethane resin (A) and an aqueous medium (B) can be used.

The aqueous urethane resin (A) can be dispersed in an aqueous medium (B) to be described later. For example, a urethane resin having a hydrophilic group such as an anionic group, a cationic group, or a nonionic group; For example, a urethane resin that is forcibly dispersed in the aqueous medium (B) can be used. These aqueous urethane resins (A) may be used alone or in combination of two or more. Among these, from the viewpoint of production stability, it is preferable to use a water-based urethane resin having a hydrophilic group, a solidification property with respect to the non-metal coagulant is further improved by the electric double layer compression effect, and is easily porous. It is more preferable to use a urethane resin having an anionic group from the viewpoint of obtaining an even better texture.

Examples of the method for obtaining the urethane resin having an anionic group include a method using, as a raw material, one or more compounds selected from the group consisting of a compound having a carboxyl group and a compound having a sulfonyl group.

Examples of the compound having a carboxyl group include 2,2-dimethylolpropionic acid, 2,2-dimethylolbutanoic acid, 2,2-dimethylolbutyric acid, 2,2-dimethylolpropionic acid, 2,2- Herbic acid or the like can be used. These compounds may be used alone or in combination of two or more.

Examples of the compound having a sulfonyl group include 3,4-diaminobutanesulfonic acid, 3,6-diamino-2-toluenesulfonic acid, 2,6-diaminobenzenesulfonic acid, N- (2-aminoethyl)- 2-Aminoethylsulfonic acid or the like can be used. These compounds may be used alone or in combination of two or more.

The carboxyl group and sulfonyl group may be partially or completely neutralized with a basic compound in the aqueous urethane resin composition. Examples of the basic compound include organic amines such as ammonia, triethylamine, pyridine, and morpholine; alkanolamines such as monoethanolamine and dimethylethanolamine; metal base compounds including sodium, potassium, lithium, calcium, and the like. Can do.

Examples of the method for obtaining the urethane resin having a cationic group include a method using one or more compounds having an amino group as a raw material.

Examples of the compound having an amino group include compounds having primary and secondary amino groups such as triethylenetetramine and diethylenetriamine; N-alkyldialkanolamines such as N-methyldiethanolamine and N-ethyldiethanolamine, and N-methyl. A compound having a tertiary amino group such as N-alkyldiaminoalkylamine such as diaminoethylamine and N-ethyldiaminoethylamine can be used. These compounds may be used alone or in combination of two or more.

Examples of a method for obtaining the urethane resin having a nonionic group include a method using one or more compounds having an oxyethylene structure as a raw material.

Examples of the compound having an oxyethylene structure include polyether polyols having an oxyethylene structure such as polyoxyethylene glycol, polyoxyethylene polyoxypropylene glycol, and polyoxyethylene polyoxytetramethylene glycol. These compounds may be used alone or in combination of two or more.

Examples of the emulsifier that can be used for obtaining the urethane resin forcibly dispersed in the aqueous medium (B) include polyoxyethylene nonylphenyl ether, polyoxyethylene lauryl ether, polyoxyethylene styryl phenyl ether, polyoxyethylene Nonionic emulsifiers such as oxyethylene sorbitol tetraoleate and polyoxyethylene / polyoxypropylene copolymers; fatty acid salts such as sodium oleate, alkyl sulfate esters, alkyl benzene sulfonates, alkyl sulfosuccinates, naphthalene sulfonates , Anionic emulsifiers such as polyoxyethylene alkyl sulfate, alkane sulfonate sodium salt, alkyl diphenyl ether sulfonate sodium salt; alkyl amine salt, alkyl trimethyl acetate Moniumu salts, and cationic emulsifiers such as alkyl dimethyl benzyl ammonium salts can be used. These emulsifiers may be used alone or in combination of two or more.

Specifically as said water-based urethane resin (A), the polyisocyanate (a1), polyol (a2), the raw material used in order to manufacture the water-based urethane resin which has an above described hydrophilic group, and a chain | strand as needed What can be obtained by using an extending | stretching agent (a3) as a raw material can be used. These reactions can use known urethanization reactions.

As the water-based urethane resin (A), an aromatic ring is used because of its low solubility in the coagulant used in the present invention, easy maintenance of a good solidified state and easy porosity, and a further improved texture. It is preferable to use a urethane resin.

The content of the aromatic ring of the aqueous urethane resin (A) is preferably in the range of 0.8 to 8 mol / kg, more preferably in the range of 1 to 6 mol / kg.

The aromatic ring is supplied from either the polyisocyanate (a1) or the polyol (a2) as a raw material, but is supplied from the polyisocyanate (a1) from the viewpoint of easy availability of the raw material and production stability. That is, it is preferable to use an aromatic polyisocyanate.

Examples of the aromatic polyisocyanate include phenylene diisocyanate, tolylene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, naphthalene diisocyanate, polymethylene polyphenyl polyisocyanate, carbodiimidized diphenylmethane polyisocyanate, and the like. These polyisocyanates may be used alone or in combination of two or more. Among these, it is preferable to use diphenylmethane diisocyanate from the viewpoint of easy availability of raw materials and texture.

Examples of other polyisocyanates that can be used in the polyisocyanate (a1) include hexamethylene diisocyanate, lysine diisocyanate, cyclohexane diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, and dimer acid diisocyanate. An aliphatic or alicyclic polyisocyanate such as norbornene diisocyanate can be used. These polyisocyanates may be used alone or in combination of two or more.

As the polyol (a2), for example, polyether polyol, polyester polyol, polyacryl polyol, polycarbonate polyol, polybutadiene polyol and the like can be used. These polyols may be used alone or in combination of two or more.

The number average molecular weight of the polyol (a2) is preferably in the range of 500 to 8,000, more preferably in the range of 800 to 4,000, from the viewpoint of the mechanical strength of the resulting film. In addition, the number average molecular weight of the said polyol (a2) shows the value measured by the gel permeation column chromatography (GPC) method.

Examples of the chain extender (a3) include ethylenediamine, 1,2-propanediamine, 1,6-hexamethylenediamine, piperazine, 2,5-dimethylpiperazine, isophoronediamine, 1,2-cyclohexanediamine, 1, Amino groups such as 3-cyclohexanediamine, 1,4-cyclohexanediamine, 4,4′-dicyclohexylmethanediamine, 3,3′-dimethyl-4,4′-dicyclohexylmethanediamine, 1,4-cyclohexanediamine, hydrazine, etc. Chain extender having: ethylene glycol, diethylene recall, triethylene glycol, propylene glycol, dipropylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, hexamethylene glycol, saccharo Scan, glycol, glycerine, sorbitol, bisphenol A, 4,4'-dihydroxydiphenyl, 4,4'-dihydroxydiphenyl ether, and the like can be used a chain extender having a hydroxyl group such as trimethylol propane. These chain extenders may be used alone or in combination of two or more. Among these, it is preferable to use a chain extender having a hydroxyl group from the viewpoint that oil grip properties and chemical resistance can be further improved.

The amount used in the case of using the chain extender (a3) is the sum of the polyisocyanate (a1), the polyol (a2) and the chain extender (a3) from the point that the durability of the film can be further improved. It is preferably in the range of 0.5 to 20% by mass, more preferably in the range of 1 to 10% by mass.

The aqueous urethane resin (A) preferably has a urea bond content of 1.2 mol / kg or less from the viewpoint that the discoloration over time can be controlled without impairing the texture.

Since the urea bond is formed when the polyisocyanate reacts with a chain extender having an amino group or an amine formed by reacting isocyanate with water, the amount of the chain extender having an amino group used is reduced. The urea bond content of the aqueous urethane resin (A) can be adjusted by adjusting and further urethanizing the isocyanate before emulsification. The urea bond content indicates a value calculated by the following general formula (1).

As a manufacturing method of the said water-based urethane resin (A), the urethane prepolymer which has an isocyanate group is manufactured by making the said polyisocyanate (a1) and the said polyol (a2) react, for example, Then, as needed The urethane prepolymer and the chain extender (a3) are reacted with each other; the polyisocyanate (a1), the polyol (a2) and, if necessary, the chain extender (a3) in a lump. And the like. These reactions can be carried out, for example, at 50 to 100 ° C. for 3 to 10 hours.

The molar ratio of the total hydroxyl group and amino group of the polyol (a2) and the chain extender (a3) to the isocyanate group of the aromatic polyisocyanate (a1) [(isocyanate group) / (hydroxyl group). And amino group)] are preferably in the range of 0.8 to 1.2, more preferably in the range of 0.9 to 1.1.

When the aqueous urethane resin (A) is produced, it is preferable to deactivate the isocyanate group remaining in the aqueous urethane resin (A). When the isocyanate group is deactivated, it is preferable to use an alcohol having one hydroxyl group such as methanol. The amount of the alcohol used is preferably in the range of 0.001 to 10 parts by mass with respect to 100 parts by mass of the aqueous urethane resin (A).

Further, when the urethane resin (A) is produced, an organic solvent may be used. Examples of the organic solvent include ketone compounds such as acetone and methyl ethyl ketone; ether compounds such as tetrahydrofuran and dioxane; acetate compounds such as ethyl acetate and butyl acetate; nitrile compounds such as acetonitrile; dimethylformamide and N-methylpyrrolidone Amide compounds and the like can be used. These organic solvents may be used alone or in combination of two or more. The organic solvent is preferably removed by a distillation method or the like when obtaining an aqueous urethane resin composition.

As the aqueous medium (B), for example, water, an organic solvent miscible with water, a mixture thereof, or the like can be used. Examples of the organic solvent miscible with water include alcohol solvents such as methanol, ethanol, n- and isopropanol; ketone solvents such as acetone and methyl ethyl ketone; polyalkylene glycol solvents such as ethylene glycol, diethylene glycol and propylene glycol; Alkyl ether solvents: lactam solvents such as N-methyl-2-pyrrolidone and the like can be used. These aqueous media may be used alone or in combination of two or more. Among these, it is preferable to use only water or a mixture of water and an organic solvent miscible with water, and more preferable to use only water from the viewpoint of safety and reduction of environmental load.

The mass ratio [(A) / (B)] between the aqueous urethane resin (A) and the aqueous medium (B) is preferably in the range of 10/80 to 70/30 from the viewpoint of workability. The range of 20/80 to 60/40 is more preferable.

The aqueous urethane resin composition used in the present invention may contain other additives as needed in addition to the urethane resin (A) and the aqueous medium (B).

Examples of the other additives include, for example, an emulsifier, a neutralizer, a thickener, a crosslinking agent, a urethanization catalyst, a silane coupling agent, a filler, a thixotropic agent, a tackifier, a wax, a heat stabilizer, and light resistance. Stabilizer, fluorescent brightener, foaming agent, pigment, dye, conductivity imparting agent, antistatic agent, moisture permeability improver, water repellent, oil repellent, hollow foam, flame retardant, water absorbent, moisture absorbent, extinguishing agent An odorant, a foam stabilizer, an antiblocking agent, an hydrolysis inhibitor, and the like can be used. These additives may be used alone or in combination of two or more.

The emulsifier may be the same as the emulsifier that can be used to obtain the aqueous urethane resin that is forcibly dispersed in the aqueous medium (B). These emulsifiers may be used alone or in combination of two or more. Among these, it is preferable to use a nonionic emulsifier from the viewpoint that the water dispersion stability of the aqueous urethane resin (A) can be improved and the texture is further improved, and the HLB (Hydrophile-Lipophile Balance) is 15 or less. Some are preferred, and 2 to 15 are more preferred.

Nonionic emulsifiers that can be preferably used include, for example, polyoxyethylene nonylphenyl ether, polyoxyethylene octylphenyl ether, polyoxyethylene distyrenated phenyl ether, polyoxyethylene lauryl ether, polyoxyethylene oleyl ether, polyoxyethylene oleyl ether, Oxyethylene stearyl ether, polyoxyethylene sorbitol tetraoleate, or the like can be used. These emulsifiers may be used alone or in combination of two or more.

The amount used in the case of using the emulsifier is preferably in the range of 0.1 to 30 parts by mass with respect to 100 parts by mass of the aqueous urethane resin (A) from the viewpoint of water dispersion stability and texture. A range of 1 to 10 parts by mass is more preferable.

The neutralizing agent neutralizes the carboxyl group when an anionic aqueous urethane resin is used as the aqueous urethane resin (A). For example, the neutralizing agent is non-volatile such as sodium hydroxide or potassium hydroxide. A tertiary amine compound such as trimethylamine, triethylamine, dimethylethanolamine, methyldiethanolamine, or triethanol; These neutralizing agents may be used alone or in combination of two or more.

The amount of the neutralizing agent used is preferably in the range of 0.8 to 1.2 times the number of moles of carboxyl groups contained in the aqueous urethane resin (A).

As mentioned above, as the aqueous urethane resin composition used in the present invention, aromatic polyisocyanate from the point that it becomes easier to coagulate with the coagulant, the point that the texture is further improved, and the water dispersion stability is improved, It is preferable to use an aqueous urethane resin composition containing an aqueous urethane resin (A) having an anionic group obtained by reacting a polyol and a chain extender, an aqueous medium (B), and a nonionic emulsifier.

In the present invention, a porous body can be easily obtained by coagulating the aqueous urethane resin composition with an aqueous nonmetallic coagulant solution. Examples of the method for producing the porous body include a method in which the aqueous urethane resin composition is applied to a substrate and immersed in the non-metal coagulant aqueous solution.

Examples of the base material include a base fabric; polyester such as polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polyolefin, polyacrylate, polyvinyl chloride, polyethylene, polypropylene ethylene vinyl alcohol, polyurethane, polyamide, polyimide, and the like. The obtained sheet or film can be used.

As the base fabric, for example, a nonwoven fabric, a woven fabric, a knitted fabric, or the like can be used. For example, polyester fiber, nylon fiber, acrylic fiber, polyurethane fiber, acetate fiber, rayon fiber, polylactic acid fiber, cotton, hemp, silk, wool, and blended fibers thereof are used as the fiber substrate. can do.

Examples of the method for applying the aqueous urethane resin composition to the substrate include, for example, a method using a roll coater, knife coater, spray coater, gravure coater, comma coater, T-die coater, applicator and the like. It is done.

Next, the coated product is further immersed in a coagulation bath of the non-metal coagulant aqueous solution, whereby the urethane resin in the aqueous urethane resin composition is coagulated to obtain a porous body. In this case, the immersion / solidification time is, for example, in the range of 1 to 30 minutes.

After obtaining the porous body, if necessary, it can be immersed in running water for 10 minutes to 2 hours after solidification to wash away unnecessary coagulants.

As described above, according to the production method of the present invention, a porous body excellent in texture can be obtained without using an organic solvent. Moreover, since it does not contain metal ions as a coagulant, it does not cause rusting or deterioration of the production apparatus when producing a coagulated product. Therefore, the porous body obtained by the production method of the present invention can be suitably used for production of gloves and synthetic leather.

As a method for producing a glove when the porous body is used for producing a glove, for example, first, a hand mold, a pipe mold or the like is first immersed in the aqueous urethane resin composition, and then the hand mold or the like is used for the nonmetal. A method of forming a solidified film on the surface of the hand mold or the like by immersing it in a coagulant aqueous solution, washing the surface with water, and drying the surface. Moreover, you may replace the order of immersion with the water-based urethane resin composition and the said nonmetallic coagulant aqueous solution.

The hand mold or tube mold may be at room temperature when immersed in the aqueous urethane resin composition, and may be heated to 30 to 70 ° C., for example.

Further, the hand shape or tube shape may be preliminarily equipped with a glove-like material or a tubular material made of knitted material such as nylon fiber.

The knitted material is not limited to the nylon fiber, but may be one made of polyester fiber, aramid fiber, cotton or the like. Moreover, the textile fabric which consists of the said fiber can also be used instead of the said knitting. Moreover, instead of the knitted fabric, a glove-like article or a tubular article made of a resin material such as vinyl chloride, natural rubber, or synthetic rubber can be used.

Further, when the porous body is used for the production of synthetic leather, by using a base fabric as the base material, a synthetic leather having a base fabric and an intermediate layer of the porous body can be obtained. Moreover, you may provide a skin layer on the said intermediate | middle layer as needed. Examples of the method for producing the skin layer on the intermediate layer include a method of applying a material for forming the skin layer on the intermediate layer and drying the material.

As the material for forming the skin layer, for example, a known aqueous urethane resin, solvent-based urethane resin, solventless urethane resin, aqueous acrylic resin, silicone resin, polypropylene resin, polyester resin, or the like can be used. These resins may be used alone or in combination of two or more.

After the synthetic leather is produced, it may be aged at 30 to 100 ° C. for 1 to 10 days, if necessary.

The synthetic leather obtained by such a method, for example, can easily produce a smooth porous body without being affected by the unevenness of the base fabric, as compared with a case where a base material is impregnated with an aqueous urethane resin composition. Can do. Further, even when the porous body is a thick film, it is very flexible, and further, since a cushion layer is formed on the surface by the porous body, it is excellent in flexibility.

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

[Synthesis Example 1] Preparation of Aqueous Urethane Resin Composition (X-1) Polycarbonate polyol ("Nipporan 980R" manufactured by Nippon Polyurethane Co., Ltd. in the presence of 3,281 parts by mass of methyl ethyl ketone and 0.1 part by mass of stannous octylate , Number average molecular weight; 2,000) 1,000 parts by mass, 17 parts by mass of 2,2-dimethylolpropionic acid, 47 parts by mass of ethylene glycol, and 344 parts by mass of diphenylmethane diisocyanate have a solution viscosity of 20,000 mPa · After reacting at 70 ° C. until reaching s, 3 parts by mass of methanol was added to stop the reaction, and a methyl ethyl ketone solution of the aqueous urethane resin (A-1) was obtained. The urethane resin solution was mixed with 70 parts by mass of polyoxyethylene distyrenated phenyl ether (Hydrophile-Lipophile Balance (hereinafter abbreviated as “HLB”); 14) and 13 parts by mass of triethylamine. An emulsified liquid in which the aqueous urethane resin (A-1) was dispersed in water was obtained by adding part by mass and emulsifying by phase inversion emulsification.
Subsequently, methyl ethyl ketone was distilled off from the emulsion to obtain an aqueous urethane resin composition (X-1) having a nonvolatile content of 40% by mass.

Synthesis Example 2 Preparation of Aqueous Urethane Resin Composition (X-2) Polyether polyol (“PTMG2000” Mitsubishi Kasei Co., Ltd.) in the presence of 3,281 parts by weight of methyl ethyl ketone and 0.1 part by weight of stannous octylate Manufactured, number average molecular weight; 2,000) 1,000 parts by mass, 17 parts by mass of 2,2-dimethylolpropionic acid, 47 parts by mass of ethylene glycol, and 344 parts by mass of diphenylmethane diisocyanate have a solution viscosity of 20,000 mPa After reacting at 70 ° C. until reaching s, 3 parts by mass of methanol was added to stop the reaction, and a methyl ethyl ketone solution of the aqueous urethane resin (A-2) was obtained. The urethane resin solution is mixed with 70 parts by mass of polyoxyethylene distyrenated phenyl ether (HLB; 14) and 13 parts by mass of triethylamine, and then 800 parts by mass of ion-exchanged water is added to effect phase inversion emulsification. An emulsion in which the urethane resin (A-2) was dispersed in water was obtained.
Subsequently, methyl ethyl ketone was distilled off from the emulsion to obtain an aqueous urethane resin composition (X-2) having a nonvolatile content of 40% by mass.

Synthesis Example 3 Preparation of Aqueous Urethane Resin Composition (X-3) In the presence of 3,281 parts by mass of methyl ethyl ketone and 0.1 part by mass of stannous octylate, polyester polyol (“Placcel 220” manufactured by Daicel Corporation, Number average molecular weight: 2,000) 1,000 parts by mass, 17 parts by mass of 2,2-dimethylolpropionic acid, 47 parts by mass of ethylene glycol, and 344 parts by mass of diphenylmethane diisocyanate have a solution viscosity of 20,000 mPa · s. Then, the reaction was stopped at 70 ° C. until the temperature reached, the reaction was stopped by adding 3 parts by mass of methanol to obtain a methyl ethyl ketone solution of the aqueous urethane resin (A-3). The urethane resin solution is mixed with 70 parts by mass of polyoxyethylene distyrenated phenyl ether (HLB; 14) and 13 parts by mass of triethylamine, and then 800 parts by mass of ion-exchanged water is added to effect phase inversion emulsification. An emulsion in which the urethane resin (A-3) was dispersed in water was obtained.
Subsequently, methyl ethyl ketone was distilled off from the emulsion to obtain an aqueous urethane resin composition (X-3) having a nonvolatile content of 40% by mass.

[Example 1]
100 parts by mass of the aqueous urethane resin composition (X-1) obtained in Synthesis Example 1, 5 parts by mass of a thickener (“Borch Gel L75N” manufactured by Borcher), a carbodiimide crosslinking agent (“Carbodilite SV manufactured by Nisshinbo Chemical Co., Ltd.) −02 ”) 4 parts by mass and 100 parts by mass of ion-exchanged water were stirred with a mechanical mixer at 2,000 rpm for 2 minutes, and then deaerated with a vacuum deaerator to prepare a blended solution.
Next, a knitted glove made of nylon fiber was attached to the hand mold, and dipped in the above mixture for 15 seconds and pulled up. Next, the hand mold was pulled up after being immersed in a coagulation bath of 40 mass% ammonium sulfate aqueous solution heated to 60 ° C. for 3 minutes. Subsequently, the hand mold was immersed in water for 60 minutes to wash away excess coagulant and dried at 120 ° C. for 30 minutes. Thereafter, the knitted gloves were removed from the hand mold to obtain a glove having a solidified film of the aqueous urethane resin composition.

[Examples 2 to 3]
A glove was obtained in the same manner as in Example 1 except that the type of the aqueous urethane resin composition used was changed as shown in the table.

[Comparative Example 1]
By mixing 100 parts by mass of the aqueous urethane resin composition (X-1) obtained in Synthesis Example 1 and 100 parts by mass of a 2% by mass aqueous solution of sodium chloride at 2,000 rpm for 2 minutes using a mechanical mixer, a compounded solution Was prepared.
Next, a knitted glove made of nylon fiber was attached to the hand mold, and dipped in the above mixture for 15 seconds and pulled up. Next, it was dried at 120 ° C. for 30 minutes. Thereafter, the knitted gloves were removed from the hand mold to obtain a glove having a heat-sensitive coagulation film of an aqueous urethane resin composition.

[Comparative Example 2]
In Example 1, it replaced with the coagulation bath of the ammonium sulfate 40 mass% aqueous solution heated at 60 degreeC, it carried out similarly to Example 1 except having used the coagulation bath of the sodium chloride 20 mass% aqueous solution of 60 degreeC, and carried out aqueous urethane. A glove having a solidified film of the resin composition was obtained.

[Measurement method of number average molecular weight]
The number average molecular weight of the polyol or the like used in the synthesis examples shows a value obtained by measurement under the following conditions by gel permeation column chromatography (GPC) method.

Measuring device: High-speed GPC device (“HLC-8220GPC” manufactured by Tosoh Corporation)
Column: The following columns manufactured by Tosoh Corporation were connected in series.
"TSKgel G5000" (7.8 mm ID x 30 cm) x 1 "TSKgel G4000" (7.8 mm ID x 30 cm) x 1 "TSKgel G3000" (7.8 mm ID x 30 cm) x 1 “TSKgel G2000” (7.8 mm ID × 30 cm) × 1 detector: RI (differential refractometer)
Column temperature: 40 ° C
Eluent: Tetrahydrofuran (THF)
Flow rate: 1.0 mL / min Injection amount: 100 μL (tetrahydrofuran solution with a sample concentration of 0.4 mass%)
Standard sample: A calibration curve was prepared using the following standard polystyrene.

(Standard polystyrene)
"TSKgel standard polystyrene A-500" manufactured by Tosoh Corporation
"TSKgel standard polystyrene A-1000" manufactured by Tosoh Corporation
"TSKgel standard polystyrene A-2500" manufactured by Tosoh Corporation
"TSKgel standard polystyrene A-5000" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-1" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-2" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-4" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-10" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-20" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-40" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-80" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-128" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-288" manufactured by Tosoh Corporation
"TSKgel standard polystyrene F-550" manufactured by Tosoh Corporation

[Evaluation method of odor during processing]
The smell was sniffed 1 m above the coagulation bath layer being processed and evaluated as follows.
“T”; feels odor.
“F”; no odor is felt.

[Evaluation Method for Adhesion State of Aqueous Urethane Resin to Fiber Substrate]
The gloves obtained in Examples 1 to 3 and Comparative Examples 1 and 2 were observed using a scanning electron microscope “SU3500” (200 × magnification) manufactured by Hitachi High-Technology Corporation, and evaluated as follows.
“T”; a porous structure is confirmed in the aqueous urethane resin layer formed on the nylon fiber.
“F”: No porous structure is confirmed in the aqueous urethane resin layer formed on the nylon fiber.

[Texture evaluation method]
The gloves obtained in Examples 1 to 3 and Comparative Examples 1 and 2 were evaluated as follows according to the touch feeling when touched with a hand.
“A”: Both the tension and the sense of fulfillment are excellent.
“B”: Feeling tight and full.
“C”; feeling of tightness and fullness are slightly inferior.
“D”; no tightness or fullness is felt.

[Example 4]
100 parts by mass of the aqueous urethane resin composition (X-1) obtained in Synthesis Example 1, 5 parts by mass of a thickener (“Borch Gel L75N” manufactured by Borcher), a carbodiimide crosslinking agent (“Carbodilite SV manufactured by Nisshinbo Chemical Co., Ltd.) −02 ”) 4 parts by mass and 100 parts by mass of ion-exchanged water were stirred with a mechanical mixer at 2,000 rpm for 2 minutes, and then deaerated with a vacuum deaerator to prepare a blended solution.
Subsequently, the said liquid mixture was apply | coated to the nonwoven fabric base material surface by knife coating (clearance of 100 micrometers). Subsequently, the coating substrate was immersed for 3 minutes in a 40% by weight ammonium sulfate aqueous solution heated to 60 ° C. to solidify the coating film. After dipping, it was immersed in water for 60 minutes to wash away excess coagulant and dried at 120 ° C. for 30 minutes to obtain an intermediate layer for synthetic leather.

[Examples 5 to 6]
An intermediate layer for synthetic leather was obtained in the same manner as in Example 1 except that the type of the aqueous urethane resin composition used was changed as shown in the table.

[Evaluation method of odor during processing]
The smell was sniffed 1 m above the coagulation bath layer being processed and evaluated as follows.
“T”; feels odor.
“F”; no odor is felt.

[Evaluation Method for Adhesion State of Aqueous Urethane Resin to Fiber Substrate]
The intermediate layer for synthetic leather obtained in Examples 4 to 6 was observed using a scanning electron microscope “SU3500” (200 times magnification) manufactured by Hitachi High-Technologies Corporation, and evaluated as follows.
“T”; a porous structure is confirmed in the aqueous urethane resin layer formed on the surface of the base fabric.
“F”: No porous structure is confirmed in the aqueous urethane resin layer formed on the surface of the base fabric.

[Texture evaluation method]
The synthetic leather intermediate layers obtained in Examples 4 to 6 were evaluated as follows according to the touch feeling when touched by hand.
“A”: Both the tension and the sense of fulfillment are excellent.
“B”: Feeling tight and full.
“C”; feeling of tightness and fullness are slightly inferior.
“D”; no tightness or fullness is felt.

Abbreviations in Tables 1 and 2 will be described.
"MDI"; diphenylmethane diisocyanate

It was found that the gloves obtained in Examples 1 to 3 according to the present invention and the synthetic leather obtained in Examples 4 to 6 were excellent in texture. In addition, since no organic solvent was used, no odor problem occurred.

On the other hand, Comparative Example 1 is a form in which coagulation was performed by thermal coagulation, but the texture was poor.

Comparative Example 2 was an embodiment in which a metal salt coagulation bath was used instead of the nonmetal coagulant, but the texture was poor.

Claims (8)

A method for producing a porous body, which comprises coagulating an aqueous urethane resin composition with an aqueous nonmetallic coagulant solution. The method for producing a porous body according to claim 1, wherein the nonmetallic coagulant is an inorganic acid ammonium. The method for producing a porous body according to claim 1 or 2, wherein the aqueous urethane resin composition contains an aqueous urethane resin (A) having an aromatic ring. The method for producing a porous body according to claim 3, wherein the content of the aromatic ring in the aqueous urethane resin (A) is in the range of 0.8 to 8 mol / kg. The method for producing a porous body according to claim 3 or 4, wherein the aqueous urethane resin (A) is made from aromatic polyisocyanate. The method for producing a porous body according to claim 5, wherein the aromatic polyisocyanate is diphenylmethane diisocyanate. A method for producing a glove having a coagulation film of an aqueous urethane resin composition, wherein the coagulation film is formed by immersing the aqueous urethane resin composition in a non-metal coagulant aqueous solution. A method for producing synthetic leather, comprising applying a water-based urethane resin composition to a base fabric and immersing it in a non-metal coagulant aqueous solution.

Images