TW201809092A - Method for producing coagulum - Google Patents

Abstract

The purpose of the present invention is to provide a method for producing a coagulum that is characterized by being obtained by coagulating an aqueous urethane resin composition using an aqueous solution of a nonmetallic coagulant agent that is heated to 40 DEG C or higher. The present invention addresses the problem of providing a production method by which it is possible to obtain a coagulum having an excellent texture without using an organic solvent. The production method according to the present invention is able to produce a coagulum of excellent texture. In addition, said production method does not employ an organic solvent in a coagulation bath, and thus is free of risk of exposure to harmful volatile substances or diffusion thereof to the environment, and enables a waste liquid of the coagulation bath to be treated by a simplified method, and thereby is able to contribute to curbing production costs. Furthermore, this production method does not use any coagulant agent that contains metal, and thus does not induce rust or deterioration to the production apparatus used for producing the coagulum. Hence, the coagulum obtained by the production method according to the present invention can be suitably used for production of gloves, coating materials, leather-like sheets, etc.

Description

Manufacturing method of solidified matter

The present invention relates to a method for producing a coagulum that can be used in, for example, the production of imitation leather sheets.

Compared with the conventional organic solvent-based urethane resin composition, an aqueous urethane resin composition system in which a urethane resin is dispersed in an aqueous medium can reduce the load on the environment. It is used as a material for manufacturing artificial leather sheets, artificial leather, synthetic leather sheets, coating agents, adhesives, and the like.

The above-mentioned imitation leather sheet is generally composed of a fibrous base material such as a non-woven fabric, an intermediate layer such as a porous layer that must be included, and a skin layer. The above-mentioned fibrous base material is to improve the bending resistance of the imitation leather sheet For the purpose of texture and texture, a fibrous base material such as a non-woven fabric is impregnated with an aqueous urethane resin composition, and is thermally coagulated (impregnated layer).

As for the aqueous urethane resin composition for impregnation of the fiber substrate, for example, an aqueous urethane resin composition is disclosed, which contains a urethane resin having a carboxyl group and / or a sulfonic acid group, A thermosetting agent and an aqueous medium (for example, refer to Patent Document 1).

However, when the urethane resin composition solidified by heat is solidified, the formulation solution of the urethane resin is accused of being once lowered in viscosity due to heating, and the resin is liable to adhere to the fiber due to capillary phenomenon. The winding point makes the resin restrain the fiber, so the softness and bendability of the obtained film are poor, and it is easy to break.

Prior art literature Patent literature

Patent Document 1 Japanese Patent Laid-Open No. 2015-7172

The problem to be solved by the present invention is to provide a method for producing a coagulum having excellent texture without using an organic solvent.

The present invention provides a method for producing a coagulum, which is obtained by solidifying an aqueous urethane resin composition in a non-metal coagulant aqueous solution at a temperature of 15 ° C or higher.

According to the manufacturing method of the present invention, a coagulum having excellent texture can be obtained. In addition, since no organic solvent is used as the coagulation bath, there is no risk of harmful volatile substances exposure or diffusion in the environment, and because the waste liquid treatment of the coagulation bath is also simplified, it also helps to reduce manufacturing costs. Furthermore, since no coagulant containing metal ions is used, no rust or deterioration of the manufacturing equipment is caused during the production of the solidified product. Therefore, the coagulum obtained by the production method of the present invention can be applied to the production of gloves, paints, and leather-like sheets.

FIG. 1 is an electron microscope photograph (a magnification of 200 times) showing a cross-sectional view of a fibrous substrate having a coagulum obtained in Example 1. FIG.

FIG. 2 is an electron microscope photograph (a magnification of 200 times) showing a cross-sectional view of a fibrous substrate having a coagulum obtained in Comparative Example 1. FIG.

Best Mode for Invention

The method for producing a coagulum according to the present invention is characterized by coagulating an aqueous urethane resin composition in a non-metal coagulant aqueous solution at a temperature of 15 ° C or higher.

In the present invention, it is important to use an aqueous solution of a non-metal coagulant as a coagulant and set it at 15 ° C or higher. In the present invention, the non-metal coagulant is used as the coagulant to improve the uniformity of the state of the adhered resin, so that a coagulated product having excellent texture can be obtained. Furthermore, since it does not contain metal ions, it does not cause solidification during manufacture. Rust and deterioration of manufacturing equipment at the time of object. In addition, by setting the aqueous coagulant solution at a temperature of 15 ° C. or higher, a good coagulation speed can be obtained, so that the aqueous urethane resin urethane resin can be coagulated, and a coagulum having excellent texture can be obtained. When the temperature of the coagulant is less than 15 ° C, the aqueous urethane resin cannot be coagulated. The temperature of the coagulation bath is preferably 17 to 100 ° C, and more preferably 20 to 80 ° C.

As the non-metal coagulant, for example, ammonium chloride, tetramethylammonium chloride, tetraethylammonium chloride, tetrapropylammonium chloride, tetrabutylammonium chloride, tetrahexylammonium chloride, and chlorine can be used. Tetraoctylammonium chloride, Tetraphenylammonium chloride, Triethylmethylammonium chloride, Triethylhexylammonium chloride, Trioctylmethylammonium chloride, Trioctylbutylammonium chloride, Chloride Trioctyl benzyl ammonium, Trimethyl benzyl ammonium chloride, tributyl benzyl ammonium chloride, triphenyl isobutyl ammonium chloride, triphenyl benzyl ammonium chloride, ammonium bromide, tetramethyl ammonium bromide, bromide Tetraethylammonium, tetrapropylammonium bromide, tetrabutylammonium bromide, tetrahexylammonium bromide, tetraoctylammonium bromide, tetraphenylammonium bromide, triethylmethylammonium bromide, bromide Triethylhexylammonium, trioctylmethylammonium bromide, trioctylbutylammonium bromide, trioctylbenzylammonium bromide, trimethylbenzylammonium bromide, tributylbenzylammonium bromide , Triphenylisobutylammonium bromide, Triphenylbenzylammonium bromide, Ammonium iodide, Tetramethylammonium iodide, Tetraethylammonium iodide, Tetrapropylammonium iodide, Tetrabutylammonium iodide Ammonium, tetrahexyl ammonium iodide, tetraoctyl ammonium iodide, tetraphenyl ammonium iodide, triethylmethyl ammonium iodide, triethylhexyl ammonium iodide, trioctyl methyl ammonium iodide, iodide Trioctylbutylammonium, trioctylbenzyl ammonium iodide, trimethylbenzyl ammonium iodide, tributylbenzyl ammonium iodide, triphenylisobutylammonium iodide, triphenylbenzyl iodide Ammonium halides such as ammonium chloride; ammonium hydrochloride, ammonium phosphate, ammonium borate, ammonium hydrofluorate, ammonium sulfate, Inorganic acid ammonium, ammonium silicate, ammonium silicate, ammonium phosphate, etc .; organic ammonium acid such as ammonium formate, ammonium acetate, ammonium propionate, ammonium malate, ammonium sulfamate, etc .; tetraphenylphosphonium chloride, tetraphenyl iodide Inorganic acids, such as phosphonium, tetramethylphosphonium bromide, tetrabutylphosphonium chloride, tetrabutylphosphonium bromide, tetrabutylphosphonium iodide, and the like; and organic acids such as tetrabutylphosphonium acetate. These non-metal coagulants can be used alone or in combination of two or more.

The above-mentioned non-metal coagulant is for reasons of suppressing the thickening and fast setting speed of the water-based urethane resin composition, resin adhesion due to capillary phenomenon, and fiber restraint, and from the viewpoint of obtaining more excellent processing cloth texture. On the other hand, among the above, those using inorganic acid ammonium are preferred, and those using ammonium sulfate are more preferred.

As the water used in the non-metal coagulant aqueous solution, for example, ion-exchanged water, distilled water, and tap water can be used. This water can be used alone or in combination of two or more.

As for the content of the non-metal coagulant, in the non-metal coagulant aqueous solution, a range of 1 to 50% by mass is preferable, and a range of 2 to 20% by mass is more preferable.

Specific aspects of the method for producing a coagulum of the present invention include, for example, impregnating a fibrous base material with an aqueous urethane resin composition, and then further impregnating the impregnated base material with a temperature of 15 ° C or higher. A method for producing a coagulated product of a urethane resin by a coagulation bath of an aqueous metal coagulant solution; impregnating a fiber substrate in a coagulation bath containing the above-mentioned non-metal coagulant aqueous solution at a temperature of 15 ° C. A method of immersing an aqueous urethane resin composition to produce a coagulated product of the urethane resin, and the like. Among them, when the former method is used, the coagulated product of the urethane resin is filled into the fiber base material, and the state where the coagulated product is entangled with the fiber base material can be formed. Therefore, it can be used as an impregnated layer of imitation leather sheet. In addition, when the latter method is used, a urethane coagulation layer can be formed on the surface of the fiber substrate and in the vicinity of the surface, and therefore it can be suitably used in the manufacture of gloves.

As the fiber substrate, for example, a nonwoven fabric, a woven fabric, a knitted fabric, or the like can be used. In terms of constituting the fiber base material, for example, polyester fiber, nylon fiber, acrylic fiber, polyurethane fiber, acetate fiber, rayon fiber, polylactic acid fiber, cotton, linen, silk, wool, and Such blended fibers and so on.

The method of impregnating the fiber base material with the aqueous urethane resin composition includes, for example, directly impregnating the fiber base material in a tank storing the waterborne urethane resin composition, and then A method such as a press to squeeze the excess. The impregnation time is, for example, in the range of 1 to 30 minutes.

Next, the impregnated base material is taken out and further immersed in the coagulation bath containing the above-mentioned non-metal coagulant aqueous solution at a temperature of 15 ° C or more, whereby the urethane resin in the aqueous urethane resin composition can be solidified. A fibrous base material in a state where solidified matter is adhered to the surface or inside of the non-woven fabric is obtained. Impregnation at this time. The setting time is, for example, in the range of 1 to 30 minutes.

The fibrous base material having a urethane resin coagulate may be impregnated as described above as necessary. After coagulation, for example, immersed in circulating water for 10 minutes to 2 hours to remove unnecessary coagulant.

Further, as a method for impregnating the fibrous substrate in the coagulation bath containing the above-mentioned non-metal coagulant aqueous solution at 15 ° C or higher, for example, the fibrous substrate is directly impregnated in the non-metallic coagulation at 15 ° C or higher. In the coagulation bath of the aqueous solution of the agent, the excess is squeezed by a roller or the like. The impregnation time is, for example, in the range of 1 to 30 minutes.

Next, the impregnated substrate is taken out and further immersed in the above-mentioned aqueous urethane resin composition, and the urethane resin in the aqueous urethane resin composition is solidified to obtain a surface layer and a surface layer of the fiber substrate. A fiber base material having a urethane coagulum layer formed in the vicinity thereof. Impregnation at this time. The setting time is, for example, in the range of 1 to 30 minutes.

The fibrous base material having a urethane resin coagulum may be impregnated as described above as necessary. After coagulation, for example, immersed in circulating water for 10 minutes to 2 hours to remove unnecessary coagulant.

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 said aqueous urethane resin (A) is a thing which can be disperse | distributed in the aqueous medium (B) mentioned later, For example, the aqueous amine which has a hydrophilic group, such as an anionic group, a cationic group, and a nonionic group, can be used. Formate resin; aqueous urethane resin, etc., which are forcibly dispersed in an aqueous medium (B) with an emulsifier. These aqueous urethane resins (A) may be used alone or in combination of two or more kinds. Among these, from the viewpoint of manufacturing stability, an aqueous urethane resin having a hydrophilic group is preferable, and from the viewpoint of further improving the coagulability of the non-metal coagulant by the compression effect of the electric double layer, From the viewpoint that the urethane resin is easily filled into the fiber base material and entangled to further improve the texture, it is more preferable to use an aqueous urethane resin having an anionic group.

As a method for obtaining the above-mentioned aqueous urethane resin having an anionic group, for example, one or more compounds selected from the group consisting of a compound having a carboxyl group and a compound having a sulfonyl group may be used as a raw material. Method.

As the compound having a carboxyl group, for example, 2,2'-dimethylolpropionic acid, 2,2'-dimethylolbutanoic acid, 2,2'-dimethylolbutyric acid, 2,2 ' -Dimethylolpropionic acid, 2,2'-valeric acid, etc. These compounds may be used alone or in combination of two or more.

For the compounds having a sulfofluorenyl group, for example, 3,4-diaminobutanesulfonic acid, 3,6-diamino-2-toluenesulfonic acid, 2,6-diaminobenzenesulfonic acid, N- (2-aminoethyl) -2-aminoethylsulfonic acid and the like. These compounds may be used alone or in combination of two or more.

The carboxyl group and the sulfonyl group are in an aqueous urethane resin composition, and may be partially or completely neutralized with a basic compound. As the basic compounds, organic amines such as ammonia, triethylamine, pyridine, and morpholin can be used; alkanolamines such as monoethanolamine, dimethylethanolamine, and the like; and sodium, potassium, lithium, and calcium can be used. Metal base compounds and so on.

As a method for obtaining the above-mentioned aqueous urethane resin having a cationic group, for example, a method of using one or two or more kinds of compounds having an amine group as a raw material.

As for the compound having an amine group, for example, a compound having a primary and secondary amine group such as triethylenetetramine and diethylenetriamine; and N-methyldiethanolamine and N-ethyldiethanolamine can be used. -Compounds having tertiary amine groups such as N-alkyldiaminoalkylamines such as alkyldialkanolamine, N-methyldiaminoethylamine, N-ethyldiaminoethylamine, etc. Wait. These compounds may be used alone or in combination of two or more.

As a method for obtaining the above-mentioned aqueous urethane resin having a nonionic group, for example, a method of using one or two or more compounds having an oxyethyl group structure as a raw material can be mentioned.

As for the compounds having an oxyethylene group, for example, polyoxyethylene glycol, polyoxyethylene polyoxypropylene glycol, polyoxyethylene polyoxytetramethylene glycol, and the like can be used. Polyether polyol with ethylene structure. These compounds may be used alone or in combination of two or more.

As the emulsifier for obtaining the above-mentioned aqueous urethane resin forcibly dispersed in the aqueous medium (B), for example, polyoxyethyl nonylphenyl ether, polyoxyethyl lauryl can be used. Nonionic emulsifiers such as ether, polyoxyethyl styrene phenyl ether, polyoxyethyl sorbitol tetraoleate, polyoxyethyl / polyoxypropylene copolymers; sodium oleate Fatty acid salts, alkyl sulfate salts, alkyl benzene sulfonates, alkyl sulfosuccinates, naphthalene sulfonates, polyoxyethyl ethyl sulfates, sodium alkane sulfonates, alkyl disulfates Anionic emulsifiers such as phenyl ether sulfonate sodium salts; cationic emulsifiers such as alkylamine salts, alkyltrimethylammonium salts, and alkyldimethylbenzylammonium salts. These emulsifiers may be used alone or in combination of two or more.

As for the above-mentioned aqueous urethane resin (A), specifically, polyisocyanate (a1), polyol (a2), and the above-mentioned raw materials used for producing the aqueous urethane resin having a hydrophilic group can be used. And those obtained by using the necessary chain elongating agent (a3) as a raw material. These reactions can be performed using conventional urethane reactions.

With respect to the aqueous urethane resin (A), the solubility to the freezing point used in the present invention is low, and it is easy to maintain a good solidified state, and the urethane resin is easily filled into the fiber substrate and entangled. From the viewpoint of further improving the texture, it is preferable to use an aqueous urethane resin having an aromatic ring.

In terms of the aromatic ring content of the water-based urethane resin (A), a range of 0.8 to 8 mol / kg is preferable, and a range of 1 to 6 mol / kg is more preferable.

The aromatic ring is supplied from any one of the polyisocyanate (a1) and the polyol (a2) of the raw materials, but is provided from the polyisocyanate (a2) in terms of ease of obtaining the raw materials and production stability. Preferably, that is, aromatic polyisocyanat is preferably used.

As the aromatic polyisocyanate, for example, phenylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, naphthyl diisocyanate, and polymethylene polyisocyanate can be used. Phenyl polyisocyanate, carbodiimidized diphenylmethane polyisocyanate, etc. 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 easiness of obtaining raw materials and texture.

For other polyisocyanates that can be used in the above polyisocyanate (a1), for example, hexamethylene diisocyanate, lysine diisocyanate, cyclohexane diisocyanate, isophorone diisocyanate, dicyclohexyl methane di Aliphatic or alicyclic polyisocyanates, such as isocyanate, phenylene diisocyanate, tetramethyl phenylene diisocyanate, dimer acid diisocyanate, norbornene diisocyanate, etc. These polyisocyanates may be used alone or in combination of two or more.

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

In terms of the number-average molecular weight of the above-mentioned polyol (a2), from the viewpoint of the mechanical strength of the obtained film, it is in the range of 500 to 8,000. Better, more preferably in the range of 800 ~ 4,000. In addition, the number average molecular weight of the said polyol (a2) shows the value measured by the gel permeation chromatography (GPC) method on the following conditions.

Measuring device: High-speed GPC device ("HLC-8220GPC" manufactured by Tosoh Corporation)

String: The following string manufactured by Tosoh Corporation is used in series.

`` TSKgel G5000 '' (7.8mmI.D. × 30cm) × 1

`` TSKgel G4000 '' (7.8mmI.D. × 30cm) × 1

`` TSKgel G3000 '' (7.8mmI.D. × 30cm) × 1

`` TSKgel G2000 '' (7.8mmI.D. × 30cm) × 1

Detector: RI (differential refractometer)

Column temperature: 40 ℃

Eluent: Tetrahydrofuran (THF)

Flow rate: 1.0mL / min

Injection volume: 100 μL (tetrahydrofuran solution with a sample concentration of 0.4% by 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

As the chain extender (a3), for example, ethylenediamine, 1,2-propanediamine, 1,6-hexamethylenediamine, piperazine, 2,5-dimethylpiperazine, and isophorone can be used. Diamine, 1,2-cyclohexanediamine, 1,3-cyclohexanediamine, 1,4-cyclohexanediamine, 4,4'-dicyclohexylmethanediamine, 3,3'-dimethyl -4,4'-dicyclohexylmethanediamine, 1,4-cyclohexanediamine, hydrazine and other chain extenders with amine groups; ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, Dipropylene Glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, hexamethylene glycol, sucrose, methyl glycol, glycerol, sorbitol, bisphenol A, 4 A chain extender having a hydroxyl group, such as 4,4'-dihydroxydiphenyl, 4,4'-dihydroxydiphenyl ether, and trihydroxypropane. These chain elongating agents may be used alone or in combination of two or more kinds. Among these, it is preferable to use a chain elongating agent having a hydroxyl group from the viewpoint of further improving oil-holding properties and chemical resistance.

From the viewpoint of further improving the durability of the film, the amount of the chain extender (a3) used is the total of the polyisocyanate (a1), the polyol (a2), and the chain extender (a3). A range of 0.5 to 20% by mass is preferable, and a range of 1 to 10% by mass is more preferable.

With respect to the aqueous urethane resin (A), the urea bond content is preferably 1.2 mol / kg or less from the viewpoint of non-destructive flavor and further control of discoloration over time.

The urea bond is an amine formed by reacting the chain extender having an amine group or an isocyanate with water, and is formed when reacting with the polyisocyanate. Therefore, the amount of the chain extender having an amine group is adjusted to further emulsify. All urethanes of the isocyanate are esterified before the operation, whereby the urea bond content of the aqueous urethane resin (A) can be adjusted. The urea bond content is a value calculated from the following formula (1).

As for the manufacturing method of the said water-based urethane resin (A), the polyisocyanate (a1) and the said polyisocyanate (a1) are mentioned, for example. A method for producing a urethane prepolymer having an isocyanate group by reacting a diol (a2), and then producing the urethane prepolymer by reacting the urethane prepolymer with the chain elongator (a3) as needed; A method of adding the above-mentioned polyisocyanate (a1), the above-mentioned polyol (a2), and the above-mentioned chain elongation agent (a3) at a time and reacting as needed. Examples of such a reaction system include those performed at 50 to 100 ° C for 3 to 10 hours.

The molar ratio of the hydroxyl group of the polyol (a2) and the hydroxyl group and / or amine group of the chain elongator (a3) to the isocyanate group of the aromatic polyisocyanate (a1) [(isocyanate group) / (Hydroxy and / or amine)], in the range of 0.8 to 1.2, more preferably, in the range of 0.9 to 1.1.

In the production of the urethane resin (A), it is preferred that the isocyanate group remaining in the urethane resin (A) is deactivated. When the isocyanate group is deactivated, an alcohol having one hydroxyl group such as methanol is preferably used. The usage-amount of the said alcohol is the range of 0.001-10 mass parts with respect to 100 mass parts of water-based urethane resin (A).

When the urethane resin (A) is produced, an organic solvent can be used. As the organic solvent, for example, 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; and nitrile compounds such as acetonitrile ; Methoxamine compounds such as dimethylformamide and N-methylpyrrolidone. These organic solvents may be used alone or in combination of two or more. The organic solvent is preferably one which can be removed by a distillation method or the like when an aqueous urethane resin composition is obtained.

As the aqueous medium (B), for example, water, an organic solvent mixed with water, and a mixture thereof can be used. For the above organic solvent mixed with water, for example, alcohol solvents such as methanol, ethanol, n- and iso-propanol; ketone solvents such as acetone, methyl ethyl ketone; ethylene glycol, diethylene glycol, Polyalkylene glycol solvents such as propylene glycol; Alkyl ether solvents of polyalkylene glycols; N-methyl-2-pyrrolidone solvents such as lactamamine; These aqueous media may be used alone or in combination of two or more. Among these, from the standpoint of reducing safety and environmental load, it is preferable to use water alone, or to use a mixture of water and an organic solvent mixed with water, and it is more preferable to use water alone.

In terms of the mass ratio [(A) / (B)] of the aqueous urethane resin (A) to the aqueous medium (B), from the viewpoint of operability, a range of 10/80 to 70/30 is preferred. A range of 20/80 ~ 60/40 is more preferable.

In addition to the urethane resin (A) and the aqueous medium (B), the aqueous urethane resin composition used in the present invention may be added with other additives as necessary.

For the other additives mentioned above, for example, emulsifiers, neutralizers, thickeners, cross-linking agents, urethane catalysts, silane coupling agents, fillers, thixotropic agents, tackifiers, waxes, Heat stabilizer, light stabilizer, fluorescent whitening agent, foaming agent, pigment, dye, conductive agent, antistatic agent, moisture permeability improver, water repellent agent, oil repellent agent, hollow foam, flame retardant Agents, water absorbents, hygroscopic agents, deodorants, foam stabilizers, anti-caking agents, and hydrolytic agents. These additives may be used alone or in combination of two or more.

The emulsifier can be the same as the emulsifier that can be used to obtain the above-mentioned aqueous urethane resin forcibly dispersed in the aqueous medium (B). These emulsifiers may be used alone or in combination of two or more. Among these, from the viewpoint of improving the water dispersion stability of the water-based urethane resin (A), and from the viewpoint that the urethane resin can be easily filled and entangled inside the fiber substrate, and can further improve the texture, it is based on the viewpoint that the texture can be further improved. A nonionic emulsifier is preferred.

In terms of the amount of the emulsifier to be used, from the standpoint of water dispersion stability and texture, it is preferably in the range of 0.1 to 30 parts by mass relative to 100 parts by mass of the aforementioned aqueous urethane resin (A). A range of 1 to 10 parts by mass is more preferred.

When an anionic water-based urethane resin is used as the water-based urethane resin (A), the neutralizing agent can neutralize the hydroxyl group. For example, sodium hydroxide, potassium hydroxide, or the like can be used. Non-volatile base; tertiary amine compounds such as trimethylamine, triethylamine, dimethylethanolamine, methyldiethanolamine, triethanolamine, etc. These neutralizing agents may be used alone or in combination of two or more.

The use amount of the neutralizing agent is preferably a range of 0.8 to 1.2 times the molar number of the carboxyl group contained in the aqueous urethane resin (A).

As mentioned above, the water-based urethane resin composition used in the present invention is from the viewpoint of easier coagulation by the coagulant described above, from the viewpoint of being easily filled and entangled inside the fiber substrate to further improve the texture, and from the viewpoint of improving water From the viewpoint of dispersion stability, anion having anion obtained by reacting an aromatic polyisocyanate, a polyol, and a chain elongating agent is used. The waterborne urethane resin (A), the aqueous medium (B), and the nonionic emulsifier based waterborne urethane resin composition are preferred.

[Example]

Hereinafter, the present invention will be described in more detail using examples.

[Synthesis Example 1] Preparation of water-based urethane resin composition (X-1)

In the presence of 3,281 parts by mass of methyl ethyl ketone and 0.1 parts by mass of stannous octoate, a polycarbonate polyol ("Nipporan 980R" manufactured by Japan Polyurethanes Co., Ltd .; number average molecular weight; 2,000) 1,000 parts by mass, 2, 17 parts by mass of 2'-dimethylolpropionic acid, 47 parts by mass of ethylene glycol, and 344 parts by mass of diphenylmethane diisocyanate. The solution viscosity reached 20,000 mPa. After the reaction at 70 ° C., 3 parts by mass of methanol was added to stop the reaction to obtain a methyl ethyl ketone solution of the aqueous urethane resin (A-1). In this urethane resin solution, 70 parts by mass of polyoxyethylene stilbene phenyl ether (Hydrophile-Lipophile Balance (hereinafter referred to as "HLB"; 14)) was mixed with triethyl After 13 parts by mass of the base amine were mixed, 800 parts by mass of ion-exchanged water was added to emulsify the phases, thereby obtaining an emulsion in which the aforementioned aqueous urethane resin (A-1) was dispersed in water.

Next, 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)

In the presence of 3,281 parts by mass of methyl ethyl ketone and 0.1 parts by mass of stannous octoate, the polyether polyol ("PTMG 2000" Mitsubishi Chemical Corporation has Co., Ltd .; number average molecular weight; 2,000) 1,000 parts by mass, 2,2'-dimethylolpropionic acid 17 parts by mass, ethylene glycol 47 parts by mass, and diphenylmethane diisocyanate 344 parts by mass. 20,000mPa. After the reaction at 70 ° C., 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-2). In this urethane resin solution, 70 parts by mass of polyoxyethylene stilbene phenyl ether (HLB; 14) and 13 parts by mass of triethylamine were mixed, and then 800 parts by mass of ion-exchanged water was added. Phase inversion emulsification to obtain an emulsion in which the above-mentioned aqueous urethane resin (A-2) was dispersed in water.

Next, 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 water-based urethane resin composition (X-3)

In the presence of 3,281 parts by mass of methyl ethyl ketone and 0.1 parts by mass of stannous octoate, a polyester polyol ("Praxel 220" manufactured by Daicel Corporation; number average molecular weight; 2,000) 1,000 parts by mass, 2,2 ' -17 parts by mass of dimethylolpropionic acid, 47 parts by mass of ethylene glycol, and 344 parts by mass of diphenylmethane diisocyanate, with a solution viscosity of 20,000 mPa. After the reaction at 70 ° C., 3 parts by mass of methanol was added to stop the reaction to obtain a methyl ethyl ketone solution of the aqueous urethane resin (A-3). In this urethane resin solution, 70 parts by mass of polyoxyethylene stilbene phenyl ether (HLB; 14) and 13 parts by mass of triethylamine were mixed, and then 800 parts by mass of ion-exchanged water was added. Phase inversion emulsification to obtain an emulsion in which the above-mentioned aqueous urethane resin (A-3) was dispersed in water.

Next, 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.

[Synthesis Example 4] Preparation of water-based urethane resin composition (X-4)

In the presence of 3,281 parts by mass of methyl ethyl ketone and 0.1 parts by mass of stannous octoate, a polycarbonate polyol ("Nipporan 980R" manufactured by Japan Polyurethane Co., Ltd .; number average molecular weight; 2,000) 1,000 parts by mass, 15 parts by mass of 2,2'-dimethylolpropionic acid and 200 parts by mass of dicyclohexylmethane diisocyanate so that the mass ratio (NCO%) of the mass of the isocyanate group to these reaction products reaches 1.13 mass% The reaction was carried out at 70 ° C to obtain a methyl ethyl ketone solution of the urethane prepolymer (X'-4) having an isocyanate group at the terminal.

Next, 2,8566 parts by mass of a methyl ethyl ketone solution of the urethane prepolymer (X'-4) and 2,566 parts by mass of water with polyoxyethylene stilbene phenyl ether ( HLB = 14) 70 parts by mass were mixed for phase inversion emulsification to obtain an emulsion in which the urethane prepolymer was dispersed in water.

The obtained emulsion was mixed with 135 parts by mass of a chain elongator aqueous solution containing 26 parts by mass of isophorone diamine to perform a chain elongation reaction to obtain a urethane resin composition.

Next, methyl ethyl ketone was distilled off from the urethane resin composition to obtain a urethane resin composition (X-4) 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 and a thickener (manufactured by Borcher Co., Ltd.) "Borch Gel L75N") 5 parts by mass, carbodiimide cross-linking agent ("Carbodilite SV-02" manufactured by Nisshinbo Chemical Co., Ltd.) 4 parts by mass, and 200 parts by mass of ion-exchanged water in a mechanical mixer at 2,000 Stir at rpm for 2 minutes, and then defoam with a vacuum defoamer to prepare a preparation solution.

Next, a non-woven fabric (250 g / m ² per unit area weight) was immersed in the above-mentioned preparation liquid, and then the unnecessary preparation liquid was squeezed so that the impregnation amount became 200% using a rubber roller. Next, the nonwoven fabric containing the preparation liquid was immersed in a coagulation bath of a 5% by mass ammonium sulfate aqueous solution heated to 60 ° C. for 3 minutes to coagulate the preparation liquid. Finally, it dried in a hot-air dryer at 100 ° C. for 30 minutes to obtain a fibrous substrate having a coagulum.

[Examples 2 to 4]

A fibrous base material having a coagulum was obtained in the same manner as in Example 1 except that the type of the aqueous urethane resin composition used was changed to that shown in the table.

[Example 5]

A fibrous base material having a coagulum was obtained in the same manner as in Example 1 except that the temperature of the coagulation bath was changed to 22 ° C.

[Comparative Example 1]

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 were stirred at 2,000 rpm for 2 minutes using a mechanical mixer. Thereby, an aqueous urethane resin composition for impregnation is prepared.

Next, a non-woven fabric (250 g / m ² per unit area weight) was dipped in a tank containing the obtained aqueous urethane resin composition for impregnation, and then this was extruded by using a rubber roller to obtain a dipped sheet. Impregnated urethane resin composition of the same quality as the above-mentioned nonwoven fabric. Next, this was dried at 100 ° C. for 10 minutes using the above-mentioned gear-type hot air dryer to obtain a fibrous base material having a coagulated solidified body by thermal sensing.

[Comparative Example 2]

In Example 1, the same operation as in Example 1 was performed except that a coagulation bath of a 5 mass% ammonium sulfate aqueous solution at 10 ° C was used instead of a coagulation bath heated to 60 ° C a 5 mass% ammonium sulfate aqueous solution. The impregnation step of the substrate, but the water-based urethane resin composition (X-1) was not solidified.

[Method for evaluating odor during processing]

Above 1 m of the coagulation bath layer during processing, an odor was smelled, and it was evaluated as follows.

"T": Smells.

"F": No odor was smelled.

[Method for measuring adhesion amount of water-based urethane resin to fiber substrate]

The fibrous substrate with coagulum obtained in the examples and comparative examples was cut into 5 cm squares, and the mass was measured with a precision balance. The fiber substrate before the impregnation step for leather was cut into 5 cm squares, and the mass was measured with a precision balance. The difference in mass between the two was measured to determine the adhesion amount (g / m ² ) of the aqueous urethane resin.

[Evaluation method of adhesion state of aqueous urethane resin to fiber substrate]

The fibrous substrate having coagulum obtained in the examples and comparative examples was observed using a scanning electron microscope "SU3500" (magnification: 200 times) manufactured by Hitachi High-Technologies Corporation, and evaluated as follows.

"T": A state where the water-based urethane resin was entangled with the fiber inside the fiber base material was confirmed.

"F": The state where the water-based urethane resin was entangled with the fiber inside the fiber base material was not confirmed.

[Texture evaluation method]

The fibrous base material having a coagulum obtained in the examples and comparative examples was evaluated as follows by the tactile sensation when touched by hand.

"A": Excellent elasticity and fullness.

"B": Feeling flexible and full.

"C": Elasticity and fullness are slightly worse.

"D": I can't feel the elasticity and fullness at all.

The abbreviations in Tables 1-2 mean the following.

"MDI": Diphenylmethane diisocyanate

"H ₁₂ MDI": Dicyclohexylmethane diisocyanate

It can be seen that Examples 1 to 5 of the present invention can obtain coagulated materials having excellent texture. In addition, it was confirmed in FIG. 1 that the coagulated product of the urethane resin was filled into the inside of the fiber base material, and a state in which the coagulated material was entangled with the fiber base material could be formed.

On the other hand, Comparative Example 1 was in a state of being solidified by thermal coagulation, but had a poor texture. In addition, it was confirmed in FIG. 2 that the urethane resin was not filled into the inside of the fiber substrate, and it was not confirmed that the resin was entangled in the fiber substrate.

Comparative Example 2 was an unheated coagulation bath and was used at a temperature of 10 ° C, but it was not coagulated.

Claims (7)

A method for producing a solidified product, which is obtained by solidifying an aqueous urethane resin composition in a non-metallic coagulant aqueous solution at a temperature of 15 ° C or higher. The method for producing a coagulated product according to claim 1, wherein the fiber substrate is impregnated in an aqueous urethane resin composition, and then immersed in a coagulation bath containing an aqueous solution of a non-metal coagulant at a temperature of 15 ° C or higher. The steps. The method for producing a coagulum according to claim 1 or 2, wherein the non-metal coagulant is an inorganic acid ammonium. The method for producing a coagulated product according to any one of claims 1 to 3, wherein the aqueous urethane resin composition is an aqueous urethane resin (A) having an aromatic ring. The method for producing a coagulum according to claim 4, wherein the aromatic ring content of the water-based urethane resin (A) is in the range of 0.8 to 8 mol / kg. The method for producing a coagulated product according to claim 4, wherein the water-based urethane resin (A) is made of an aromatic polyisocyanat as a raw material. The method for producing a coagulum according to claim 6, wherein the aromatic polyisocyanate is diphenylmethane diisocyanate.