WO2003042271A1

WO2003042271A1 - Solventless, moisture-curable hot-melt urethane resin composition, foamed product and sheet structure using the same

Info

Publication number: WO2003042271A1
Application number: PCT/JP2002/006009
Authority: WO
Inventors: Yoshinori Kanagawa; Toshio Niwa; Masahiko Takahashi
Original assignee: Dainippon Ink And Chemicals, Inc.
Priority date: 2001-11-09
Filing date: 2002-06-17
Publication date: 2003-05-22
Also published as: TWI316064B

Abstract

A solventless, moisture-curable hot-melt urethane resin composition, characterized in that it comprises a hot-melt urethane prepolymer containing an isocyanate group (A), a compound at least two active hydrogen atoms (B) and water (C), wherein the ratio of the equivalents of the isocyanate group in the prepolymer (A) and the total equivalents of reactive groups in a compound at least two active hydrogen atoms (B) and water (C) [equivalents of NCO group (A)/total equivalents of reactive groups in (B+C)] is in the range of 1.5 to 20.0.

Description

Specification

Solvent-free moisture-curable hot melt urethane resin composition,

Foam and sheet structure using the same

The present invention relates to a novel and useful solvent-free moisture-curable hot-melt polyurethane resin composition, a foam, a sheet structure using the same, and a method for producing the sheet structure. Background art

Conventionally, polyurethane resins have been widely used for artificial leather and synthetic leather. Artificial leather or synthetic leather broadly refers to a sheet-like material obtained by combining a polyurethane resin composition with a non-woven fabric, a woven fabric, a knitted fabric, or the like. Has been classified.

That is, the term “artificial leather” refers to a sheet-like material in which a polyurethane resin composition is filled or laminated on a nonwoven fabric, and is generally manufactured by using dimethylformamide (hereinafter, referred to as a polyurethane resin composition). The solution was impregnated or coated on the nonwoven fabric, and the polyurethane resin was coagulated in a water coagulation bath or a coagulation bath composed of a DMF-water mixed solution to form a porous material. Thereafter, it is obtained by a method of passing through a washing step and a drying step, a so-called wet processing method.

On the other hand, “synthetic leather” is generally roughly classified into wet synthetic leather and dry synthetic leather, and refers to a sheet-like material obtained by laminating a polyurethane resin composition on a woven or knitted fabric. Generally, a wet synthetic leather is manufactured by impregnating or coating a woven or knitted fabric with a DMF solution of a polyurethane resin composition, and then forming the solution into a water coagulation bath or a mixed solution of DMF and water. It is obtained by a so-called wet processing method in which a polyurethane resin is coagulated in a coagulation bath to form a porous body, and then subjected to a washing step and a drying step. Dry synthetic leather is manufactured by mixing polyurethane resin with pigments, solvents, and additives and stirring to dissolve the coating resin for the skin. After adjusting the liquid, apply it on the release paper that has been shaped, and dry the solvent.- Apply a liquid polyurethane resin adhesive to the release paper, and laminate it with a base cloth such as a brushed cloth. After that, the solvent is dried and then aged to produce a multilayered processed body for leather by laminating various skin coating films on a base fabric without forming a porous layer. Since solvent-based urethane resin is used in these processing methods, it is essential to dry the solvent and extract the solvent during the processing process, which causes adverse effects on the human body, problems with environmental pollution, and evaporation of the solvent. There is a problem of energy cost, etc., and the demand for the transition from solvent type to non-solvent type resin or the transition to solvent-free type processing method is increasing recently.

Water-based methods are being studied as a solvent-free method, but their practical use is limited due to poor water resistance and durability. Solvent-free liquid crosslinked resins also have difficulty in adjusting the cohesive force during processing such as application and lamination because the development of cohesive force depends on crosslinking, making application to synthetic leather processing difficult. .

Also, “solvent-free moisture-curable (reactive) hot menole urethane” used for adhesives and coating materials by heating and melting a solid reactive resin at room temperature is well known. Conventionally, as an example of foaming a reactive hot melt urethane, a method of introducing an inert gas under pressure into a reactive hot menole urethane in a molten state (European Patent Publication No. 405, 721) However, if the composition is not pressurized and released to ambient pressure, the foam has an inhomogeneous state and has the disadvantage of insufficient cell shape and mechanical strength.

Further, a method for producing a urethane foam obtained by blending a polyol and water (a foaming agent) with an isocyanate component and foaming the same (European Patent Publication No. 572/8333) is disclosed. However, foams produced by such a method have a large amount of water and a polyol, so that the reaction with prepolymer is fast, it is difficult to form a film of synthetic leather or artificial leather, and the crosslink density of the film itself is low. Due to the low properties, there is a drawback that physical properties such as heat resistance and water decomposability of cauldron are inferior. Disclosure of the invention

An object of the present invention is to provide excellent adhesiveness and durability based on a moisture curing reaction, A solvent-free moisture-curable hot menoletourethane resin composition that provides a high-performance porous layer that has both foaming properties to obtain a uniform cell shape in addition to water-decomposability and heat resistance, and foaming using the same. An object of the present invention is to provide a body, a sheet structure using the same, and a method for manufacturing the sheet structure.

The present invention relates to an isocyanate group-containing hot melt urethane prepolymer (A) [hereinafter referred to as a prepolymer (A)], a compound (B) having at least two active hydrogen atoms [hereinafter referred to as an active hydrogen-containing compound (B)]. , And water (C) as essential components, and the ratio of the NCO group equivalent of the prepolymer (A) to the total reactive group equivalent of the active hydrogen-containing compound (B) and water (C) [NCO group equivalent (A) total reactive group Equivalent (B + C)] in the range of 1.5 to 20.0. It is intended to provide a solventless moisture-curable hot menoleto urethane resin composition.

The present invention also provides a foam obtained by mixing and stirring the solvent-free moisture-curable hot-melt urethane resin composition in a state where the composition is heated and melted, foamed with water, and then moisture-cured. is there.

In addition, the present invention provides a method of mixing and stirring a non-solvent type moisture-curable hot melt urethane resin composition on a substrate and heating and melting the same on the substrate, foaming with water, and moisture-curing foaming. A sheet structure having a body is provided.

Furthermore, the present invention relates to a base material and a sheet which is mixed and stirred in a state where the solvent-free moisture-curable hot-menole polyurethane resin composition is heated and melted on the base material, foamed with water and laminated, and then moisture-cured. It is intended to provide a method for manufacturing a structure. BEST MODE FOR CARRYING OUT THE INVENTION

Necessary items for implementing the present invention are described below.

In the present invention, the prepolymer (A), preferably an isocyanate group-terminated urethane prepolymer having a softening point in the range of 30 to 160 ° C., and if necessary, a prepolymer (A) containing an alkoxysilyl group-terminated urethane prepolymer, ), Active hydrogen containing compound

(B) and water (C), and the ratio of the total reactive group equivalents of the active hydrogen-containing compound (B) and water (C) to the NCO group equivalent of the prepolymer (A) [NCO group equivalent (A) total reaction Base equivalent (B + C)] is in the range of 1.5 to 20.0. By mixing and stirring and foaming with water in a state where the solvent-free moisture-curable hot-melt urethane resin composition is heated and melted, a foam is formed based on the moisture-curing reaction, thereby providing excellent adhesiveness, A solventless moisture-curable hot-melt urethane resin composition capable of obtaining a high-performance porous layer having foaming properties in addition to durability (in particular, hydrolysis resistance and heat resistance), and a uniform cell shape; A foam and a sheet structure using the same can be obtained.

First, the prepolymer (A), which is a main component of the solventless moisture-curable hot melt urethane resin composition, will be described.

The prepolymer (A) used in the present invention is an isocyanate group-terminated urethane prepolymer (a-1) in which an isocyanate group obtained by a reaction between a polyol component and a polyisocyanate component is left, or a polyol component and a polyisocyanate. -Has at least one active hydrogen atom per molecule that reacts with the isocyanate group and has a hydrolyzable alkoxysilyl group and isocyanate group obtained by reacting a compound having a hydrolyzable silyl group per molecule. Urethane prepolymer (a-

2), preferably a urethane prepolymer having an isocyanate group terminal (a-1) or a urethane prepolymer having a hydrolyzable alkoxysilyl group and an isocyanate group (a-2). Things.

The isocyanate group-terminated urethane prepolymer (a_l) reacts the polyol component with the polyisocyanate component when the equivalent ratio of the NCO group of the isocyanate to the hydroxyl group of the polyol exceeds 1, that is, the NCO group is excessively reacted. It can be obtained by: The equivalent ratio of NCO groups / hydroxyl groups is usually preferably in the range of 1.1 to 5.0, more preferably in the range of 1.5 to 3.0. If the equivalent ratio of NCO group / hydroxyl group is in such a range, it is possible to obtain excellent processing suitability, foam stickiness, and appropriate crosslinking density.

The alkoxysilyl group-terminated urethane prepolymer (a-2) has at least one active hydrogen atom per molecule that reacts with the polyol component, the polyisocyanate component, and the isocyanate group, and And a compound having a hydrolyzable silyl group. Usually, the above-mentioned poly (urethane prepolymer having an isocyanate group) has one of a functional group capable of reacting with an isocyanate group and a hydrolyzable silyl group. Is used to introduce a hydrolyzable silyl group into the molecular terminal by reacting a compound having the following. In addition to the above, by reacting a polyurethane resin having an isocyanate group and a compound having both a hydrolyzable silyl group and two functional groups capable of reacting with an isocyanate group, a hydrolyzable silyl group is formed in the molecule. An alkoxysilyl group-terminated urethane prepolymer having the above is obtained.

Examples of the polyol component constituting the prepolymer (A) used in the present invention include a polyester polyol, a polyether polyol, and a mixture or copolymer thereof. Further, acrylic polyols, polycarbonate-based polyols, lactone-based polyols, polyolefin-based polyols, castor oil-based polyols, polyhydric alcohols, and the like, or mixtures or copolymers thereof, may be mentioned.

Examples of the polyester-based polyol include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, 2,2-dimethyl-1,2 3—Prono ,. 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,8-octanediol, diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol, cyclohexane One, two or more diols such as 1,1,4-dioneole, cyclohexane-1,4-dimethanole, and bisphenanol A EO adducts or P〇 adducts with succinic acid, maleic acid, adipic acid, and dartaric acid And condensates with one or more dicarboxylic acids such as pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, phthalic acid, isophthalic acid, terephthalic acid, and hexahydroisophthalic acid. . In addition, ring-opening polymers such as y-butyrolactone and f-caprolactone using the above-mentioned glycol component as an initiator can also be used. In the present invention, E O means ethylene oxide, and P O means propylene oxide.

Examples of polyether polyols include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butylene glycolone, 1,4-butylene glycolone, 2,2 —Dimethinoles 1, 3—Pro Pandiol, 1,6-hexanediol, 3-methynole-1,5-pentanediol, 1,8-octanediol, diethylene glycolone, triethylene glycol, dipropylene glycol, tripropylene glycol, cyclohexane Glycol components such as 1,4-dioxane and cyclohexane-1,4-dimethanol, or ethylene oxide, propylene oxide, butylene oxide starting with the polyester polyol, Styrene oxide alone or two or more ring-opening polymers may, for example, be mentioned. Further, ring-opening addition polymers such as γ-butyrolactone and _ε -force prolactone to these polyether diols can be used. Further, known polyhydric alcohols can also be used.

, 1,2-propylene glycolone, 1,3-propylene glycolone, 1,3-butylene glycolone, 1,4-butylene glycol, 2,2_dimethyleneone 1,3-propanediol, 1,5- Pentanediole, 3-methylinole 1, 5-pentanodiol, 1, 6-hexanediole, 1,8-octanediole, diethylene glycol, triethylene glycol, dipropylene glycol, propylene glycolonele, Dalicol components such as cyclohexane-1,4-diolone and cyclohexane-1,4-dimethanol are exemplified.

The polyisocyanate component that can be used in the present invention is not particularly limited, but includes, for example, phenylene diisocyanate, tolylene diisocyanate (TDI), 4,4′-diphenylmethane Aromatic diisocyanates such as diisocyanate, 2,4-diphenyl methane diisocyanate, naphthalenedi succinate, etc., hexamethylene diisocyanate, lysine diisocyanate, and cyclohexane diisocyanate And aliphatic or alicyclic diisocyanates such as isophorone diisocyanate, dicyclohexylmethane diisocyanate, xylylene diisocyanate, and tetramethylxylylene isocyanate. These polyisocyanate components may be used alone or in combination of two or more. Of these, diphenylmethane diisocyanate (MDI), which has a low vapor pressure during heating, is preferably used in consideration of being used for hot melt urethane resin which is used by melting. The compound having one or more active hydrogen atoms per molecule which can react with an isocyanate group and having a hydrolyzable silyl group which can be used in the present invention has an active hydrogen atom which reacts with an isocyanate group. There is no particular limitation as long as the compound has at least one functional group per molecule and has a hydrolyzable silyl group. Examples of the functional group having an active hydrogen atom include an amino group, a hydroxyl group, and an SH group. Among them, an amino group is preferable because of its excellent reactivity with an isocyanate group. On the other hand, the hydrolyzable silyl group includes, for example, a silyl group that is easily hydrolyzed, such as a halosilyl group, an alkoxysilyl group, an acyloxysilyl group, a phenoxysilyl group, an iminooxysilyl group, or an alkenyloxysilyl group. However, more specifically, those represented by the following general formula [1] are exemplified.

I General formula [1]

-S i-(R ₂ ) ₃ - _n

(However, R i in the general formula [1] is a hydrogen atom or a monovalent organic group selected from an alkyl group, an aryl group or an aralkyl group, and R ₂ is a halogen atom or an alkoxyl group, an acyloxy group, a phenoxy group, Represents an iminooxy group or an alkenyloxy group, and n represents an integer of 0, 1 or 2.)

Among the above hydrolyzable silyl groups, a trimethoxysilyl group, a triethoxysilyl group, a (methyl) dimethoxysilyl group, a (methyl) diethoxysilyl group, and the like are preferable because the bridge is easily advanced.

Examples of the compound having a functional group capable of reacting with an isocyanate group and a hydrolyzable silyl group used in the present invention include, for example, (2-aminoethyl) aminopropyltrimethoxysilane, γ- (2-hydroxylethyl) amino Propyltrimethoxysilane, γ- (2-aminoethyl) aminopropyltriethoxysilane, 7- (2-hydroxyethyl) aminopropyltriethoxysilane, γ- (2-aminoethyl) aminopropylmethyldimethoxysilane, · Ν— (2-amino Ethyl) aminopropylmethyl ethoxysilane, γ- (2-hydroxyethyl) aminopropylmethyldimethoxysilane, γ- (2-hydroxyethylethyl) aminopropylmethyl ethoxysilane or γ- (Ν, Νdi) 1-Hydroxysilethyl) aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-aminopropylmethylethoxysilane or γ — (Ν-phenyl) 'aminoprovir trimethoxysilane and the like.

The softening point of the prepolymer (Α) used in the present invention is preferably in the range of 30 to 160 ° C, more preferably 40 to 100 ° C. C range. If the softening point of the prepolymer (A) is in the above range, a stable and uniform foam without unevenness can be obtained, and the cooling and solidifying time of the foamed cells foamed with water can be optimized.

The method for adjusting the softening point of the prepolymer (A) used in the present invention is not particularly limited, and includes, for example, (1) a method for adjusting the molecular weight (the molar ratio between the polyol component and the polyisocyanate component, (2) the use of a molecular weight polyol, (2) Adjustment method based on the crystallinity of the ethylene chain of the polyester polyol, (3) Adjustment method based on the aromatic structure of the polyol component and polyisocyanate component, (4) Adjustment method based on urethane bond, etc.

In order to prepare the prepolymer (A) used in the present invention, various known and common methods can be used, and there is no particular limitation.

Generally, in the case of an isocyanate group-terminated urethane prepolymer (a-1), a polyol component from which water has been removed is added dropwise to the raw material isocyanate component and heated to react until the hydroxyl group of the polyol component is eliminated. Obtained. In the case of an alkoxysilyl group-terminated urethane prepolymer (a-2), an alkoxysilane compound having a group that reacts with an NCO group is added dropwise to the isocyanate group-terminated urethane prepolymer as obtained above. To obtain a reaction. This reaction is carried out in the absence of a solvent, but may also be carried out in an organic solvent, followed by removing the solvent. When the reaction is carried out in an organic solvent, various commonly used organic solvents such as ethyl acetate, n-butyl acetate, methyl ethyl ketone, and toluene can be used, and any organic solvent that does not inhibit the reaction can be used. Not limited. In this case, After completion of the reaction, it is necessary to remove the solvent by a desolvation method represented by heating under reduced pressure.

Next, in the present invention, the active hydrogen-containing compound (B) to be mixed with the prepolymer (A) includes, for example, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycolone, and 1,3-propylene glycol. 'Tylene glycolone, 1,4-butyrene glycolone, 2,2-dimethinole 1,3-propanediole, 1,6-hexanediole, 3-methinole 1,5-pentanediole, 1,8—octanediol, diethylene glycolone, triethylene glycolone, dipropylene glycolone

Ethylene oxide, propylene oxide starting from a polyol such as tripropylene glycolone, cyclohexane-1,4-diolone, cyclohexane-1,4-dimethanol, or the above-mentioned polyester polyol as an initiator. And butylene oxide and styrene oxide alone or in combination of two or more ring-opening polymers. Also, polyfunctional polyols such as trifunctional and tetrafunctional polyols may be mentioned. Also, _I-loop 'Chiroraku tons to these Porietenore system Porionore, .epsilon. force Puroraku tons ring opening addition polymers of such like can be used. Also, ethylenediamine, 1,3-propylenediamine, 1,2-propylenediamine, hexamethylenediamine, norpollenenediamine, hydrazine, piperazine, N, N'-diaminobiperazine, 2-methylbiperazine , 4,4'-Diaminodicyclohexylmethane, isophorone diamine, diaminobenzene, diphenylmethanediamine, methylenebisdichloroaline, triethylenediamine, tetramethylhexamethylenediamine, triethylamine, triethylamine Use of polyamines such as propylamine, trimethylaminoethylpiperazine, メチル -methylmonoleophorin, Ν-ethynolemonorefolin, di (2,6-dimethylmonorefolinoethyl) ether, and one or a mixture of two or more it can. However, polyols are preferred in view of processing suitability because the reaction with the isocyanate group during processing is slow and the crosslinking rate is easy to control. As long as the processability is not impaired, the use of the above-mentioned polyamine used alone as a raw material of the urethane resin alone or in combination with the above-mentioned polyol is not particularly limited.

In the resin composition of the present invention, water (C) is an essential component as a foaming agent. The reaction between the prepolymer (Α) and water (C) generates carbon dioxide gas, which is an object of the present invention. However, if the amount of water (C) is too high, carbon dioxide gas will be generated too much, resulting in uneven thickness and poor surface condition of the foam, or a decrease in workability due to gelation. Nare, selected by range.

The water (C) used in the present invention is an essential component for mixing and stirring to foam with water in a state where the prepolymer (A) and the active hydrogen-containing compound (B) are melted by heating, and in some cases, urethane. A foaming catalyst and a foam stabilizer may be added. When only the prepolymer (A) and the active hydrogen-containing compound (B) are used, the melt viscosity increases, but the water required for foaming with water is insufficient and foaming is difficult, and the prepolymer (A) and water

In the case of only (C), the foaming is slight, but the foam is collapsed because the melt viscosity after foaming does not rise sharply, and it is difficult to fix the foam. Therefore, the combination of the prepolymer (A), the active hydrogen-containing compound (B), and water (C) provides an excellent balance between foam fixation due to the rise in melt viscosity and foamability due to water. It becomes better when a urethane-forming catalyst and a foam stabilizer are added.

The addition amount of the active hydrogen-containing compound (B) and water (C) is determined by the ratio of the total reactive group equivalent of the active hydrogen-containing compound (B) and water (C) to the NCO group equivalent of the prepolymer (A) [N CO Group equivalent (A) / total reactive group equivalent (B + C)] Force Preferably in the range of 1.5 to 20.0, more preferably in the range of 2.0 to 15.0, particularly preferred The range is 2.0 to 10.0. Within such a range, the active hydrogen-containing compound (B) may be used to fix the cell by increasing the melt viscosity, and may be formed by foaming with water (C) and a moisture curing reaction of free NCO groups after foaming with water. A good balance of heat resistance due to the formation of the three-dimensional structure.

The ratio of the reactive group equivalents of the active hydrogen-containing compound (B) and water (C) used in the present invention [reactive group equivalent (B) Z reactive group equivalent (C)] is within a range that achieves the object of the present invention. And preferably in the range of 0.5 to 10.0, more preferably in the range of 1.0 to 5.0.

In addition, the amount of water (C) added is such that the NCO group equivalent (A) and the total reactive group equivalent (B + C) are within the range of 1.5 to 20.0, and the prepolymer (A) The amount can be preferably 0.05 to 5.0 parts by weight, more preferably 0.10 to 2.0 parts by weight, per 100 parts by weight. If the amount of water added is within this range, the foaming degree is appropriate Yes, the surface state of the obtained foam is good.

The solvent-free moisture-curable hot menoletourethane resin composition of the present invention contains the prepolymer (A), the active hydrogen-containing compound (B), and water (C) as essential components, In this state, it is preferable to mix and stir a urethanization catalyst, a foam stabilizer, and the like, and each of them can be used alone or two or more of them can be added.

The urethanization catalyst used in the present invention includes, for example, an amine catalyst, an organometallic catalyst, an amidine catalyst, and the like, and is preferably an amine catalyst.

The amine catalyst (D) used in the present invention is preferably an amine catalyst having a catalyst constant ratio KW ₂ / of 0.5 or more. In the present invention, KW ₂ is a catalytic constant per weight of the reaction between water and tolylene diisocyanate (TDI), and KW ₂ is the reaction constant between diethylene glycol (DEG) and tolylene diisocyanate (TDI). It shall represent the catalyst constant per weight.

KW and KW ₂ is a catalytic constants of such amine catalyst (D) is a constant obtained by measurement of the kinetics of the formation reaction formula of poly urethane (1) and (2).

Scheme (1) RNCO + R 'OH → RNHC (= 〇) OOR' reaction formula _{(2) 2RNCO + H 2 0} → RNHC (= 0) NHR + CO 2 The measuring method of the reaction rate, A. F According to the method of arkas [Reference: J. Am. Chem. Soc. 82, 642 (1960)] 30. In the benzene solution at C, the reaction rate constant of water and TDI (K ₂ ) and the reaction rate constant of TDI and DEG (Κ 丄) were measured, and for convenience, the catalyst constant per weight was KW ₂ And and.

Examples of the amine catalyst (D) used in the present invention include N, N-dimethylcyclohexylamine (DMCHA), N-methyldicyclohexylamine (MD CHA), N, N, Ν ', N'-tetramethyl Ethylenediamine (TMEDA), Ν, Ν, Ν ', Ν'-tetramethylpropylenediamine (TMPDA), Ν, Ν, Ν', Ν'-tetramethylhexamethylenediamine (TMHMDA), Ν, Ν, N ', Ν ", Ν" —pentamethylethylenepropylenetriamine (ΡΜΕΡΤΑ), Ν , N, Ν ', N ", N" -pentamethyldipropylenetetraamine (PMDPTA), N, N, Ν', Ν ", Ν '", Ν "'-hexamethinoresylene propylene ethylenetetraamine ( HMAPEDA), Ν, Ν'_dimethylbiperazine (DMP), Ν, Ν, Ν'-trimethyl-1-aminoethylpiperazine (ΤΜΝΑΕΡ), Ν-methyl monoreforin (ΝΜΜΟ), Ν-hydroxyxenotinole To monorefolin (ΗΕΜΟ), Ν, Ν, Ν ', N'—tetramethyldipropylene ethylene glycol diamine (Τ MEGDA), Ν, Ν, Ν', Ν ", Ν '", Ν'"— Xamethyltetraethylenetetraamine (ΗΜΤΕΤΑ), Ν, Ν-dimethyl ^ / aminoethylethanol ether

(DMAE Ε), Ν, Ν, N'-trimethylaminoethylethanolamine (Τ ΜΑΕΕΑ), Ν, Ν, Ν ', Ν'-bisdimethylaminoethyl ether (BDM EE), triethylamine (TEA), N, Examples include amine catalysts such as N, N ', N ", N" -pentamethyldiethylenetriamine (PMDETA). It is preferable to use an amine catalyst having a value of KWzZKWi of 0.5 or more, which is a ratio of the catalyst constant, because the foaming property by the reaction with water is excellent. In some cases, if the above-mentioned amine catalyst is an essential component, a urethanization catalyst other than the above, or an organometallic catalyst, an amidine catalyst or the like may be used alone or in combination of two or more.

The amount of the urethanization catalyst to be used is preferably 0.05 to 10 parts by weight, more preferably 0.1 to 5.0 parts by weight, per 100 parts by weight of the prepolymer (A). When the amount of the urethane-forming catalyst is within the above range, the foaming property by the reaction with water is excellent, the gelation does not occur, and the workability is good.

Further, in the solvent-free moisture-curable hot melt urethane resin composition of the present invention, if necessary, a foam stabilizer (E) can be used at the time of use as long as the original moisture curability is not impaired. .

As the foam stabilizer (E), for example, those containing 10% by weight or more of a polysiloxane-polyoxyalkylene copolymer used for an organosilicon surfactant or the like are preferable. Examples of the foam stabilizer (E) include, but are not limited to, Toray Dow Corning 'Silicone Co., Ltd. product names SF 2969, PRX607, SF 2964, S RX 274C, SF 2961, SF 2962 , SF 2965, SF 2908, BY 10—123, SF 2904, SRX294A, BY 10-54 0, SF 2935 F, SF 2945 F, SF 2944 F, SF 2936 F, SH 193, SH 192H, SH I 92, SF 2909, SH1 94, SH I 90, SRX280A, SRX298, etc. Product names L580, SZ1127, SZ1111, SZ1136, SZ1919, SZ1105, SZ1142, SZ1162, L3601, L5309, L-5366 , SZ1 306, SZ1311, SZ1313, SZ1342, L5340, L5420, SZ1605, SZ1627, SZ1642, SZ1649, SZ1671, SZ1675, SZ1 923 and the like.

In addition, foam stabilizer (E) and, if necessary, bis (2-ethylhexyl) phthalate (DOP) diisonol adipate (DI NA) bis (2-ethylhexyl) adipate (DOA) etc. Plasticizers and polyether-based surfactants such as EOZPO copolymers.

The amount of the foam stabilizer (Ε) used is preferably in the range of 0.1 to 20 parts by weight, more preferably in the range of 0.5 to 10 parts by weight, based on 100 parts by weight of the prepolymer (Α). is there. As long as the amount of the foam stabilizer (Ε) used is within the above range, the foam stabilizer is excellent, and the physical mechanical strength of the foam after aging is excellent.

The solvent-free moisture-curable hot-melt urethane resin composition of the present invention further comprises a curing accelerator, an antioxidant, an ultraviolet absorber, a light resistance stabilizer, a silane coupling agent, a tackifier, a wax, and a plasticizer. Additives such as stabilizers, fillers, thixotropic agents, pigments, fluorescent brighteners, organic foaming agents and inorganic foaming agents, and thermoplastic resins and the like may be used alone or in combination.

Examples of the silane coupling agent include γ-glycidoxypropyl trimethoxysilane, γ-glycidoxypropyl methyl ethoxysilane, β- (3,4-epoxycyclohexyl) ethynoletrimethoxysilane, methacryloxypropyl Examples include trimethoxysilane, γ-mercaptopropyltrimethoxysilane, vinyltrimethoxysilane, and γ-clopropylpropyltrimethoxysilane.

Examples of the filler include calcium carbonate, aluminum hydroxide, barium sulfate, kaolin, talc, carbon black, alumina, magnesium oxide, Inorganic and organic balloons;

As the thixotropic agent, surface-treated calcium carbonate, finely divided silica, bentonite, sepiolite and the like can be used. In particular, the addition of a thixotropic agent is preferred from the viewpoint of stabilizing the foam after foaming.

When the alkoxysilyl group-terminated urethane prepolymer (a-2) is used, a crosslinking catalyst can be added as necessary. Examples of such a crosslinking catalyst include various acidic compounds such as malic acid and citric acid, various basic compounds such as lithium hydroxide, sodium hydroxide, potassium hydroxide, and triethylenediamine; tetraisopropyl titanate; Various metal-containing compounds, such as di-n-butyltin dilaurate, di-n-butyltin oxide, dioctyltin oxide or di-n-butyltin maleate, and generally as a catalyst for crosslinking alkoxysilyl groups It is used and is not particularly limited.

The solvent-free moisture-curable hot-melt urethane resin composition of the present invention has a crosslinking reactivity (moisture-curing) and a hot-melt property (solid at room temperature, but melts when heat is applied so that it can be applied and cooled) ). The cross-linking reaction of the resin composition of the present invention occurs when the isocyanate group in the prepolymer or the isocyanate group and the hydrolyzable silyl group react with moisture.

Examples of the method for processing the solvent-free moisture-curable hot-melt urethane resin composition of the present invention include, for example, a prepolymer (A), an active hydrogen-containing compound (B), and water (C) as essential components. Add a urethane-forming catalyst such as an amine-based catalyst (D), a foam stabilizer (E), etc., mix and stir in a heated and molten state, foam with water, and take advantage of hot-melt properties and moisture-curing properties. In order to control the shape of the cells of the foamed layer from the closed cell state to the open state, it is also possible to mix and stir an inert gas. Examples of such an inert gas include nitrogen, a rare gas, carbon dioxide, an aliphatic hydrocarbon, and a halogenated hydrocarbon.

The foam of the present invention is a solvent-free moisture-curable hot menoletourethane resin composition as described above. It is obtained by mixing and stirring in a state where the product is heated and melted, foaming with water, and then curing with moisture.

Most of the foams (also referred to as cells in the present invention) in such foams are usually closed cells (independent bubbles), but bubbles (cells) communicating with a part thereof may be mixed. . The size can be appropriately controlled, but the diameter is preferably about 5.0 to 200 μπι. The thickness of the foam is not particularly limited, but is preferably about 0.05 to 1.0 mm particularly when used for synthetic leather or artificial leather. The size of the foam and the thickness of the foam are also applicable to the foam layer obtained from the solvent-free moisture-curable hot menoletourethane resin composition of the present invention in the sheet structure described below. Is done.

The degree of foaming of the foam of the present invention can be appropriately adjusted according to its use, and is not particularly limited as long as it does not impair feel or strength. For example, for artificial leather or synthetic leather, the degree of foaming is preferably in the range of 1.5 to 3.0 times. Here, the "degree of foaming" is the ratio of the volume of the foamed resin before (V and after foaming of the resin body volume (V _2). Such degree of foaming, in the sheet structure which will be described later The present invention is also applicable to a foamed layer obtained from the solventless moisture-curable hot melt urethane resin composition of the present invention.

A sheet structure can be obtained from the solventless moisture-curable hot menoletourethane resin composition of the present invention and a sheet substrate. That is, a sheet structure can be obtained by applying the resin composition in a heated and melted state on a sheet substrate, foaming with water, and then curing with moisture to form a foamed layer. Needless to say, a sheet structure in which a sheet base is further laminated on the foamed layer, or a sheet structure in which a foamed layer made of the above resin composition is integrated between three or more sheet bases, can be used.

Examples of the sheet substrate constituting the sheet structure of the present invention include, for example, nonwoven fabrics, woven fabrics, base fabrics and natural leathers generally used for artificial leather and synthetic leather, such as knitted fabrics, various plastic sheets, It is not limited as long as it is a film, a film with release paper, release paper, paper, or the like. Further, a base cloth impregnated with at least one kind of solvent-based and water-based polyurethane resin, acrylic resin, rubber-based (SBR, NBR) latex, etc., can be used. , Impregnated with water-based resin The sheet structure using the base cloth is more preferable in terms of environmental friendliness.

The film as the sheet substrate and the film with release paper used in the present invention are preferably polyurethane resins conventionally used for artificial leather or synthetic leather, and are usually solvent-based resins, water-based resins, hot-melt resins, etc. Can be obtained by coating on a release paper and drying.

The foam and the sheet structure according to the present invention were obtained by mixing the solvent-free moisture-curable hot melt urethane resin composition according to the present invention under heating and melting with an inert gas, if necessary, and foaming with water. The foamed resin is evenly laminated and cooled and solidified, for example, between the release paper, between the sheet substrate and the release paper, between the base fabric and the leather-like film, or between the release paper and the water-repellent cloth and film. There is no particular limitation as long as it is a method that can be crosslinked and processed. Further, after preparing such a foam, the sheet base material may be subjected to bonding processing using a solvent-based adhesive and a Z- or water-based adhesive, or a hot-melt adhesive. In order to promote foaming and curing of the foam, humidify the surface of the substrate or the surface of the foam to which the foam is bonded, or the surface of the substrate or the surface of the foam to which the foam is integrated. Processing may be performed.

When producing the foam and the sheet structure according to the present invention, the solvent-free moisture-curable hot-melt urethane resin composition of the present invention is heated and melted, and foamed with water. The temperature is not lower than the temperature at which the prepolymer (A) is melted, preferably from 60 to 200 ° C. If the temperature is too high, it is difficult to control foaming and it is difficult to obtain a uniform foam, which is not preferable.

As an apparatus for producing the foam or sheet structure in the present invention, for example, industrially, a tank for heating and melting the prepolymer (A), a tank for storing and supplying water and other additives, and a tank for storing and supplying water and other additives are used. A tank for mixing the materials, a belt for continuously transporting release paper and sheet base material, a nozzle for supplying the molten resin composition onto the belt, a humidifying chamber for curing the foam, and heating if necessary It consists of a chamber, another sheet base supply section, and the like. The above-described devices are representative and may be variously modified.

There is no particular limitation on the equipment for foaming the resin using the inert gas in combination, as long as the equipment is capable of uniformly mixing the inert gas with a predetermined amount. Cooling due to agitation during mixing of the body 增 Viscosity does not result in uniform foaming 不良 When processed as a foam on a substrate, film, or sheet, poor coating or poor adhesion occurs without flowing In order to avoid this, a structure that can heat and maintain the mixture is desirable.

There are no particular restrictions on various processing methods, such as surface processing on the foam or sheet structure obtained by the present invention by known and conventional lamination or coating, or buffing.

As described above, the foam and the sheet structure obtained by using the solventless moisture-curable hot-melt urethane resin composition of the present invention are particularly excellent in adhesiveness and durability (in particular, hydrolysis resistance and heat resistance). Excellent and uniform cell shape can be obtained.

The solvent-free moisture-curable hot-melt urethane resin composition of the present invention, and a foam or a sheet structure using the same can be used for, for example, synthetic leather and artificial leather used for shoes, furniture, clothing, vehicles, bridges, cases, and the like. Used for adhesives, adhesives, sealing agents, paints, coatings, films, sheets, heat insulation, heat insulation, sound absorbing materials, cushioning materials, slip stoppers, polishing pads, electronics, electronics It can be used for a wide range of applications, such as building materials, civil engineering, medical parts, etc.

Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited to these Examples. In the following, the section and. All / ₀ values are by weight unless otherwise specified. Various properties of the resin were measured according to the following methods.

[Measurement method of melt viscosity]

The melt viscosity of each of the prepolymers obtained in Examples and Comparative Examples was measured at a measurement temperature of 125 ° C. using a cone plate viscometer (manufactured by ICI).

[Measurement method of softening point]

The softening point (dry-ball softening point) of each of the prepolymers obtained in the examples and comparative examples was measured at a heating rate of 5 min using rign g a d n d b a l m e t ho d.

[Method of measuring foaming degree]

An active hydrogen-containing compound (B) and water (C) were mixed and stirred into a pre-polymer (A) melted at 120 ° C and foamed with water (V) of the resin composition before foaming and water. Later tree The ratio [Vz / Vi] to the volume (V ₂ ) of the fat composition was measured and defined as the degree of foaming.

[Adhesiveness evaluation method]

A cloth hot menoleto tape is thermocompressed at 130 ° C for 5 seconds on the skin film 1 of the sheet structure aged for 5 days at an environment of 23 ° C and 65% relative humidity, and then a head of 200 mm / min. The peel strength was measured at a speed according to j IS K6311 using Tensilon, and the adhesiveness was evaluated.

[Method for evaluating hydrolysis resistance]

After subjecting the sheet structure to a hydrolysis resistance test (jungle test conditions: 70 ° C, 95% relative humidity, holding for 12 weeks), measure and maintain the peel strength in the same manner as the above-mentioned evaluation method of adhesion. The ratio and the change in appearance after the evaluation were observed and evaluated according to the following criteria.

〇: No change in appearance after jungle test.

X: Appearance change after jungle test.

[Method of evaluating heat resistance]

After subjecting the sheet structure to a heat resistance test (test conditions: holding at 120 ° C for 500 hours), the peel strength was measured in the same manner as the above-mentioned method of evaluating the adhesiveness, and the retention rate and the appearance change after the evaluation were measured. Was observed and evaluated according to the following criteria.

〇: No change in appearance after test.

X: Appearance change after test.

[Production method of skin film 1]

Crisbon NB761F (Dainippon Ink and Chemicals Co., Ltd.), a solvent-type urethane resin for the skin of synthetic leather, DI LAC-6001 (Dainippon Ink Kagaku Kogyo Co., Ltd.), and methylethyl Mix and stir ketone (MEK) and dimethylformamide (DMF), and apply evenly on a release paper using knife coater so that the coating amount is 100 g / m ² (wet). After drying at 70 ° C. for 1 minute and then at 120 ° C. for 2 minutes, a skin film 1 having a thickness of 30 μm was prepared. << Example 1 >> Manufacturing method of sheet structure 1

70 parts of polytetramethylene glycol (hereinafter abbreviated as PTMG) with a number average molecular weight of 1400, adipic acid (abbreviated as ΑΑ in the table), and hexanediol (abbreviated as HG in the table) with a number average molecular weight of 1,400 in a 4-liter flask Has a number average molecular weight of 2000 30 parts of the polyester polyol (described as polyester polyol 2000 in the table) was heated under reduced pressure to 120 ° C. and dehydrated until the water content became 0.05%. After cooling to 40 ° C, add 25 parts of 4,4'-diphenylmethane diisocyanate (MDI), raise the temperature to 90 ° C, and react for 3 hours until the NCO content becomes constant As a result, a prepolymer 1 was obtained. The viscosity at 125 ° C with a cone plate viscometer is 8000 mPa · s, and the NCO content is 2.1 weight ⁰ /. Met. While prepolymer 1 is heated to 120 ° C and melted and heated at 120 ° C, ethylene glycolone (EG), water, POLYCAT-8 [Air Products] It was confirmed from the volume that N, N-dimethylcyclohexylamine (DMCHA) manufactured by Japan Co., Ltd. was mixed and stirred at 120 ° C. and foamed about 2.0 times. Immediately apply it to the skin film 1 with a thickness of 50 μm, cool it, bond it with the urethane-impregnated nonwoven fabric, and leave it for 5 days in an environment at a temperature of 23 ° C and a relative humidity of 65% to obtain a sheet structure. Got body 1. The results of evaluating the properties of the sheet structure 1 of the present invention are shown in Table 1, and the sheet structure 1 of the present invention was excellent in adhesiveness, foaming property, hydrolysis resistance and heat resistance.

<< Example 2 >> Manufacturing method of sheet structure 2

A 1-liter 4-neck flask has 20 parts of PTMG with a number-average molecular weight of 1400, and a polyester resin with a number-average molecular weight of 2000 of adipic acid (abbreviated as AA in the table) and hexanediol (abbreviated as HG in the table). Eighty parts were heated under reduced pressure to 120 ° C and dehydrated until the water content became 0.05%. After cooling to 40 ° C, add 22 parts of 4,4'-diphenylmethane diisocyanate (MDI), then raise the temperature to 90 ° C, and keep it for 3 hours until the NCO content becomes constant The reaction yielded prevolimer 2. The viscosity at 125 ° C with a cone plate viscometer is 950 OmPa · s, and the NCO content is 2.1 weight ⁰ /. Met. While preprelimer 2 is heated to 120 ° C and melted and heated at 120 ° C, ethylene glycol (EG), water and POLYCAT-8 are mixed and stirred according to the composition of the foamed layer shown in Table 1. It was confirmed from the volume that foaming was about 2.2 times. Immediately, it is coated on the skin film 1 with a thickness of 50 μm, cooled, bonded to the urethane-impregnated nonwoven fabric, and left for 5 days in an environment at a temperature of 23 ° (65% relative humidity) to obtain a sheet structure. The result was 2. Evaluation of the characteristics of the sheet structure 2 of the present invention The results are shown in Table 1. The adhesive, foaming, hydrolysis and heat resistance were excellent.

<< Example 3 >> Manufacturing method of sheet structure 3

The prepolymer 1 obtained in Example 1 was heated and melted at 120 ° C., and then heated to 120 ° C., and propylene glycol having a number average molecular weight of 1 000 (P PG 1 000) and dibutyl ditin dilaurate (DB SNDL) was mixed and stirred at a weight ratio of Prepolymer 1 // PPG100 / DB SNDL = 1 00 / 3.0 / 0.1 to obtain Prepolymer 3, and the composition of the foam layer in Table 1 was obtained. According to the above, water and POLYCAT-8 were mixed and stirred, and it was confirmed from the volume that foaming was performed about 2.0 times. Immediately after the foamed pre-polymer 3 was obtained, it was coated on the skin film 1 with a thickness of 50 μm, cooled and bonded to a urethane-impregnated nonwoven fabric, and the temperature was 23 ° C and the relative humidity was 65%. The sheet structure 3 was obtained by being left for a day. The results of evaluating the properties of the sheet structure 3 of the present invention are shown in Table 1, and it was found that the sheet structure 3 was excellent in adhesiveness, foamability, hydrolysis resistance, and heat resistance.

<< Example 4 >> Manufacturing method of sheet structure 4

The prepolymer 1 obtained in Example 1 was heated and melted at 120 ° C., and then heated at 120 ° C., while mixing the EG, water, POLYCAT-8, It was confirmed from the volume that a foaming agent (SF2962, manufactured by Dow Corning Toray Silicone Co., Ltd.) was mixed and agitated and foamed about 2.2 times. Immediately apply it to the skin film 1 with a thickness of 50 μm, cool it, bond it with a polyurethane-impregnated nonwoven fabric, and leave it at a temperature of 23 ° (:, relative humidity 65% for 5 days. The sheet structure 4 was obtained, and the evaluation results of the properties of the sheet structure 4 of the present invention are shown in Table 1. The sheet structure 4 was excellent in adhesiveness, foaming property, hydrolysis resistance and heat resistance.

<< Comparative Example 1 >>'' While prepolymer 1 obtained in Example 1 was heated to 120 ° C, melted and heated at 120 ° C, according to the composition of the foam layer in Table 2, only prepolymer 1 was used. Although the mixture was stirred, the degree of foaming was 1.0 times, and it was confirmed that almost no foaming occurred. Immediately, apply it to the skin film 1 with a thickness of 50 μm, cool it, bond it with a polyurethane-impregnated nonwoven fabric, and leave it for 5 days at a temperature of 23 ° C and a relative humidity of 65%. Thus, a sheet structure 5 was obtained. Table 2 shows the evaluation results of the properties of the sheet structure 5. There was almost no foaming property.

<< Comparative Example 2 >>

EG, water and POLYCAT-8 were mixed and stirred according to the composition of the foamed layer shown in Table 2, while heating and melting the prepolymer 1 obtained in Example 1 at 120 ° C and heating at 120 ° C. It was confirmed that the degree of foaming was 3.0 times. Immediately, it is applied to the skin film 1 at a thickness of 50, cooled, bonded to the urethane-impregnated nonwoven fabric, and left for 5 days in an environment of a temperature of 23 ° C and a relative humidity of 65% to obtain a sheet structure 6. Was obtained. Table 2 shows the characteristic evaluation results of the sheet structure 6. This product was over-foamed, the foam cells were non-uniform and the surface properties were poor, and the adhesive properties, hydrolysis resistance and heat resistance were poor.

Table 2

Industrial applicability

The solvent-free, moisture-curable hot-melt urethane resin composition of the present invention comprises:

-A hot melt urethane prepolymer (Α) containing a compound (Β) having at least two active hydrogen atoms and water (C) are heated and melted, mixed, stirred and foamed with water to form a skin material. Highly flexible, uniform foaming, adhesion, and durability (especially hydrolysis resistance and heat resistance) by coating on top Since the foam and sheet structure useful for leather and the like can be adjusted without solvent, the solvent drying and extraction steps, which are indispensable for conventional solvent-based adhesives, are not required. The problem, the energy cost required for evaporating and removing the solvent, and the equipment problem can be improved. Further, the solvent-free moisture-curable hot melt urethane resin composition, foam and sheet structure using the same according to the present invention can be used for synthetic leather or artificial leather used for shoes, furniture, clothing, vehicles, tiredness, cases and the like. In addition, for example, adhesives, adhesives, sealing agents, paints, coatings, films, sheets, heat insulating materials, heat insulating materials, sound absorbing materials, cushioning materials, non-slip, polishing pads, electric appliances, electronics, building materials, It is extremely practical for a wide range of applications such as civil engineering and medical components. Further, the present invention provides a method for producing the sheet structure.

Claims

The scope of the claims

1. A solventless moisture-curable hot melt urethane resin composition,

An isocyanate group-containing hot melt urethane prepolymer (A), a compound (B) having at least two active hydrogen atoms, and water (C) are essential components, and at least active hydrogen atoms are equivalent to the isocyanate group equivalent of the prepolymer (A). Ratio of total reactive group equivalents of two compounds (B) and water (C) [NCO group equivalent (A) / total reactive group equivalent (B + C)], in the range of 1.5 to 20.0 It is.

2. The solvent-free moisture-curable hot-melt urethane resin composition according to claim 1, wherein the softening point of the prepolymer (A) is in the range of 30 to 160 ° C.

3. The solvent-free moisture-curable hot-melt urethane resin composition according to claim 1,

The prepolymer (A) is an isocyanate group-terminated polyurethane prepolymer obtained by reacting a polyol component with a polyisocyanate component.

4. The solvent-free moisture-curable hot menoletourethane resin composition according to claim 1,

The ratio of the total reactive group equivalent of the compound (B) having at least two active hydrogen atoms and the water (C) to the isocyanate group equivalent of the prepolymer (A) [NCO group equivalent (A) total reactive group equivalent (B + C)], 2.0 to 15.0.

5. The solvent-free, moisture-curable hot menoletourethane resin composition according to claim 1,

Prepolymer (A) Power Contains a urethane prepolymer terminated with an isocyanate group and a urethane prepolymer having a hydrolyzable alkoxysilyl group and an isocyanate group.

6. The solvent-free moisture-curable hot-melt urethane resin composition according to claim 1,

Ratio of reactive group equivalents of compound (B) having at least two active hydrogen atoms and water (C) [Reactive group equivalent (B) Z reactive group equivalent (C)] i in the range of 0.5 to 10.0 It is.

7. The solvent-free moisture-curable hot-melt urethane resin composition according to claim 1, further comprising an amine catalyst (D) as an essential component.

8 ・ The solventless moisture-curable hot menoletourethane resin composition according to claim 7,

Amine catalyst (D), the ratio of the catalyst constants KWzZKW i [where KW ₂ is the catalyst constant per weight of the reaction between water and tolylene disuccinate; Represents the catalytic constant per weight of the reaction with the range succinate] is 0.5 or more.

9. The solventless moisture-curable hot melt urethane resin composition according to claim 7, further comprising a foam stabilizer (E) as an essential component.

10. The solvent-free moisture-curable hot melt urethane resin composition according to claim 9, comprising a foam stabilizer (E) and a polysiloxane-polyoxyalkylene copolymer.

11. A foam obtained by heating and melting the resin composition according to any one of claims 1 to 10, mixing and stirring, foaming with water, and then curing with moisture.

12. A sheet structure obtained by laminating the foam of claim 11 on a sheet substrate.

13. The resin composition according to any one of claims 1 to 10 is heated and melted on the sheet base material. A method for producing a sheet structure that is melted, foamed and laminated with water, and then moisture-cured.