JP2003277601A - Composite polyurethane resin aqueous dispersion - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aqueous dispersion of a composite polyurethane resin which is excellent in adhesiveness to various base materials as an adhesive, and excellent in heat resistance after bonding processing, and further excellent in workability under low temperature conditions of 80 ° C or lower. Provide body. SOLUTION: A composite polyurethane obtained from a self-emulsifying hydrophilic urethane prepolymer containing terminal isocyanate group (A) and a hydrophobic resin (B) having a number average molecular weight of 500 to 20,000. It is an aqueous resin dispersion, and the ratio of (A) and (B) is (A) / (B) = 9
The weight ratio is from 9/1 to 40/60 solids, and (A) has an anionic group as a hydrophilic group, or an anionic group and a nonionic group. Further, the aqueous adhesive and the aqueous coating agent contain the aqueous dispersion.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aqueous dispersion of a composite type polyurethane resin capable of exhibiting excellent performance mainly when used as a base resin for an aqueous adhesive and an aqueous coating agent. More specifically, it has excellent adhesiveness and heat resistance to various base materials, and is suitable for adhesion processing, impregnation processing, backing processing, laminating processing, coating processing of plastic, leather, rubber, paper, wood, fiber, metal, glass, etc. It relates to a useful composite polyurethane resin aqueous dispersion.

[0002]

2. Description of the Related Art Generally, various base materials such as rubber, leather, metal, plastics such as polyvinyl chloride (PVC), foams and the like are used as a polyurethane aqueous solution, a dispersion, and an aqueous adhesive obtained by using these. When using and adhering, it is important to develop high adhesive strength immediately after adhering and over time even if processing is performed under different conditions such as various production lines and processing temperatures. In particular, in the processing method (dry laminating processing, vacuum forming processing, processing temperature: about 50 to 80 ° C.) after bonding water after removing the solvent, the adhesiveness of the adhesive near the processing temperature is determined. It is very important in designing a resin whether to develop the balance and maintain the heat resistance while keeping the balance. Therefore, it has been strongly desired to provide an aqueous adhesive having a good balance between processability at low temperature and heat resistance.

Also, as a coating agent, polyurethane resin water dispersions have been widely used as various binders, paints, and primer coating agents for the purpose of easy adhesion. In particular, in surface modification (primer coating) of a plastic substrate, a urethane-based water-based primer coating agent has been the mainstream because it can be processed at a high temperature of about 150 ° C or higher. However, in recent years, there has been a strong demand for a primer coating agent capable of modifying the surface of a base material under processing conditions at low temperatures in order to prevent thermal deformation of the base material, and conventional products have not been satisfactory.

A method for producing an aqueous polyurethane resin dispersion is described in, for example, US Pat. No. 3,036,998.
It is described in US Pat. No. 3,756,992 etc. and is known.

Further, Japanese Patent Publication No. Sho 61-35212 discloses a method for producing a polyurethane resin water dispersion, which comprises mixing a hydrophilic urethane prepolymer having an ethylene oxide group and a hydrophobic urethane prepolymer. ing. However, in this publication, the ethylene oxide group is added to the hydrophilic urethane prepolymer in an amount of 40 to
Since it contained 98% by weight, the water-resistant peel strength after adhesion processing was remarkably reduced, and the water resistance required as a water-based adhesive could not be satisfied.

Further, in JP-A-2-20511, production of an aqueous dispersion of a polyurethane resin characterized in that a substantially water-insoluble isocyanate group-terminated prepolymer is emulsified and dispersed with a self-dispersible water-soluble polyurethane. The method is described. However, in this publication, since a water-soluble polyurethane partially containing the hydrophilic group is used, depending on the composition, the decrease in molecular weight due to hydrolysis becomes remarkable, and there is a problem that the particle stability decreases.

Further, in Japanese Patent Laid-Open No. 7-157527,
A production method is described in which a tackifier (tackifier) is combined with an aqueous urethane resin. The publication describes improvement of adhesion to an olefin substrate by compounding a tackifier, but in general, addition of a tackifier generally results in a decrease in cohesive force of a resin resulting in substrate adhesion. However, there is a problem that it is difficult to optimize the balance between adhesive strength and heat resistance.

[0008]

The object of the present invention is that it has excellent adhesiveness to various substrates as an adhesive, heat resistance after adhesion processing, and further has excellent processing suitability under low temperature conditions of 80 ° C. or lower. An object is to provide an aqueous dispersion of a composite polyurethane resin.

[0009]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found that a specific composite type polyurethane resin water dispersion shown below is used as an aqueous adhesive and an aqueous coating agent. As a result, they have found that they have excellent adhesiveness to various base materials, heat resistance after adhesive processing, and further have excellent processability under low temperature conditions of 80 ° C. or lower, and have completed the present invention.

That is, the present invention is a self-emulsifying hydrophilic urethane prepolymer containing a terminal isocyanate group (A),
The present invention relates to a composite polyurethane resin aqueous dispersion, which is obtained from a hydrophobic resin (B) having a number average molecular weight of 500 to 20,000.

The present invention also relates to an aqueous adhesive containing the above-mentioned composite type polyurethane resin aqueous dispersion.

Furthermore, the present invention relates to an aqueous coating agent containing the above-mentioned composite type polyurethane resin aqueous dispersion.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The necessary items for carrying out the present invention will be described below.

The composite polyurethane resin aqueous dispersion of the present invention comprises a self-emulsifying hydrophilic urethane prepolymer (A) containing terminal isocyanate groups and a number average molecular weight of 500.
Obtained with the hydrophobic resin (B) in the range of up to 20,000.

The terminal isocyanate group-containing hydrophilic urethane prepolymer (A) used in the present invention means a high molecular weight polyol, a low molecular weight polyol,
It means a urethane prepolymer having an isocyanate group at the terminal, which is obtained from a substance having active hydrogen selected from at least one kind of polyamine having a molecular weight of 300 or less and polyisocyanate, and can be dispersed alone in water.

The high molecular weight polyol used in the production of the terminal isocyanate group-containing hydrophilic urethane prepolymer (A) preferably has a hydroxyl value of 10 to 350 m.
The range is gKOH / g (the unit is omitted hereinafter), and the hydroxyl value is more preferably 20 to 300. The "hydroxyl value" referred to herein is the number of mg of potassium hydroxide required to neutralize the acetic acid bound to the hydroxyl group when 1 g of the sample is acetylated.

Representative examples of the high molecular weight polyols used in the present invention include polyester polyols, polyether polyols, polycarbonate polyols and the like, and these high molecular weight polyols may be used alone or in a mixture or a copolymer. . In particular, polyester polyol is mainly used because of its adhesiveness to a wide range of substrates and its price.

The above-mentioned polyester polyol is prepared by reacting various conventionally known polycarboxylic acids or their various reactive derivatives with various conventionally known polyol compounds having a molecular weight of 300 or less by various conventionally known methods. To be done.

Examples of the polycarboxylic acids include succinic acid, succinic anhydride, adipic acid, suberic acid, azelaic acid, sebacic acid, dimer acid, maleic anhydride,
Fatty acids (alicyclic) dicarboxylic acids such as fumaric acid and 1,4-cyclohexanedicarboxylic acid, polycarboxylic acids such as trimellitic acid and pyromellitic acid cyclohexanetricarboxylic acid as polyfunctional components, and their anhydrides or ester-forming derivatives , Terephthalic acid, isophthalic acid, phthalic acid, 1,4-naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, naphthalic acid, biphenyldicarboxylic acid, 1,2-bis (phenoxy) Examples thereof include aromatic dicarboxylic acids such as ethane-p, p'-dicarboxylic acid and their acid anhydrides or ester-forming derivatives, aromatic hydroxycarboxylic acids such as p-hydroxybenzoic acid and their ester-forming derivatives. These polycarboxylic acids may be used alone or in combination of two or more. Examples of the cyclic ester include ε-caprolactone, γ-valerolactone and the like.

On the other hand, as typical polyols having a molecular weight of 300 or less that can be used in the production of the hydrophilic urethane prepolymer (A) containing terminal isocyanate groups, particularly representative examples are ethylene glycol, propylene glycol and 1,3- Propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, diethylene glycol, triethylene glycol,
Tetraethylene glycol, dipropylene glycol,
Tripropylene glycol, polyethylene glycol,
3-methyl-1,5-pentanediol, 2-butyl-
Aliphatic diols such as 2-ethyl 1,3-propanediol, alicyclic diols such as 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, hydrogenated bisphenol A, bisphenol A, hydroquinone and bishydroxyethoxy. Examples of the polyol include benzene and alkylene oxide adducts thereof, and polyfunctional components such as glycerin, trimethylolpropane, and pentaerythritol. These polyols having a molecular weight of 300 or less may be used alone or in combination of two or more kinds.

Further, as a particularly representative example of the polyether polyol, ethylene oxide in the presence of a compound having an active hydrogen atom (reactive hydrogen atom),
It is a polymer obtained by ring-opening polymerization of various three-membered or four-membered ring ether compounds such as propylene oxide, butylene oxide, styrene oxide, tetrahydrofuran or epichlorohydrin, or a mixture of two or more thereof. Typical examples of the above polyether polyol include polyethylene glycol, polypropylene glycol, polytetramethylene glycol and the like. These polyether polyols may be used alone or in combination of two or more kinds. Further, a polyether monool partially blocked with a monoalcohol such as methanol or butanol may be used in a range that does not hinder the increase in the molecular weight.

Further, as typical examples of the polycarbonate polyols, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, polyethylene glycol, polypropylene glycol or polytetramethylene glycol can be given. And the like, and a reaction product of a dialkyl carbonate represented by dimethyl carbonate or the like or a cyclic carbonate represented by ethylene carbonate or the like.
These polycarbonate polyols may be used alone or in combination of two or more.

In the present invention, as the hydrophilic group for imparting water dispersibility (hydrophilicity) to the polyurethane resin, an anionic group represented by a carboxylate group and / or a sulfonate acid group has a solubility in water. Strongly preferred as a hydrophilic group.

The content of the hydrophilic group in the solid content of the polyurethane resin has a strong correlation with the particle size when the polyurethane resin is made into an aqueous dispersion, and the hydrophilicity of the carboxylate group and / or the sulfonate group is high. The amount of the functional group is preferably adjusted to 50 to 1000 mmol / kg based on the solid content of the polyurethane resin. Within such a range, the particle stability will be in a suitable range without impairing water resistance.

In order to neutralize the carboxylate groups and / or sulfonate groups contained in the polyurethane resin, for example, ammonia, organic amines such as triethylamine, alkanolamines such as monoethanolamine,
At least one neutralizing agent selected from metal bases such as pyridine, morpholine, Na, K, Li and Ca can be used.

Typical examples of the polyol compound containing a carboxylate group include 2,2'-dimethylolpropionic acid, 2,2'-dimethylolbutanoic acid, 2,2'-dimethylolbutyric acid, and 2,2'-dimethylolbutanoic acid. Examples thereof include 2'-dimethylol valeric acid, which may be a carboxylate group-containing polyester polyol obtained by using these as a polyol component when synthesizing a polyester.

A polyester polyol containing a sulfonate group may be used as the polyol component. Representative examples include 5-sulfoisophthalic acid, sulfoterephthalic acid, and 4-sulfoisophthalic acid containing a proton, a metal ion such as Na, K, Li, and Ca, and an organic amine such as diethylamine and triethylamine as cations in the sulfonate group. -Polyester polyols containing aromatic sulfonate groups, including dicarboxylic acids such as sulfophthalic acid, 5 [4-sulfophenoxy] isophthalic acid or ester derivatives thereof, and JP-B-49-366.
As described in No. 93, diaminosulfonate and the like can be used.

A nonionic group-containing compound such as a polyethylene-polyalkylene copolymer having a molecular weight of 300 to 10,000 and containing at least 30% by weight of repeating units of ethylene oxide and further containing at least one active hydrogen group. Can be used together. It is preferable that the content of the nonionic group is adjusted to 0 to 20% by weight based on the solid content of the polyurethane resin. Within such a range, the particle stability will be in a suitable range without impairing water resistance.

The low molecular weight polyol used in the present invention is
The same polyols as those described as specific examples of the polyol having a molecular weight of 300 or less in the preparation of the polyester polyol can be used. Further, monoalcohol may be used as long as the cohesive force of the resin is not impaired. Representative examples include monoalcohol compounds having a molecular weight of 300 or less, such as methanol, ethanol, n-butanol, isopropanol, and n-hexanol.

Typical examples of polyamines having a molecular weight of 300 or less that can be used in the production of the terminal isocyanate group-containing hydrophilic urethane prepolymer (A) that can be used in the present invention include 1,2-diaminoethane.
1,2- or 1,3-diaminopropane, 1,2-
Or 1,3- or 1,4-diaminobutane,
1,5-diaminopentane, 1,6-diaminohexane, piperazine, N, N′-bis- (2-aminoethyl)
Piperazine, 1-amino-3-aminomethyl-3,5
5-trimethyl-cyclohexane (isophoronediamine), bis- (4-aminocyclohexyl) methane, bis- (4-amino-3-butylcyclohexyl) methane,
Diamines such as 1,2-, 1,3- or 1,4-diaminocyclohexane or 1,3-diaminopropane,
Polyamines such as diethylenetriamine and triethylenetetramine, and further hydrazine or hydrazine derivatives such as adipic acid dihydrazide, Canadian Patent No. 928,3
No. 23, those described in JP-B-49-36693, diaminosulfonate and the like can be used.

Furthermore, amino alcohols having an amino group and an alcoholic hydroxyl group in the molecule can be used, and examples thereof include ethanolamine, N-methyldiethanolamine, propanolamine, N-methyldiisopropanolamine and N-ethyl. Examples include diethyleneamine, N-ethyldiisopropanolamine, aminoethylethanolamine, diethanolamine and the like.

Generally, polyamines and amino alcohols are used for the purpose of increasing the molecular weight and imparting durability (heat resistance, etc.) by extending the residual isocyanate groups of the prepolymer. , And amino alcohol may be used in the prepolymer production stage. As the polyamine used in the present invention, in order not to impair durability, a polyamine having a functional group number of 2 or more may be used alone, and it is preferable to use two or more kinds in combination so that the average functional group number is 2 or more. The polyamine having a molecular weight of 300 or less can be preferably used in a ratio of 1.9 equivalents or less with respect to the residual isocyanate groups, and more preferably used in a range of 0.6 to 1.0 equivalents for chain extension. Within this range, a high molecular weight is obtained, and excellent durability and light resistance can be exhibited.

In the present invention, the organic polyisocyanate used in preparing the aqueous polyurethane resin dispersion is a compound represented by the following general formula [1]. R (NCO) n General formula [1] (wherein, R is an arbitrary divalent organic group, n ≧ 2). Any conventionally known polyisocyanate compound can be used. However, to exemplify a particularly typical one among them, 1,4-tetramethylene diisocyanate,
1,6-hexamethylene diisocyanate, 1,12-
Dodecamethylene diisocyanate, cyclohexane-
1,3- or 1,4-diisocyanate, 1-isocyanato-3-isocyanatomethyl-3,5,5-trimethylcyclohexane (also known as isophorone diisocyanate; IPDI), bis- (4-isocyanatocyclohexyl) methane (also known as water) MDI), 2- or 4-isocyanatocyclohexyl-2'-isocyanatocyclohexylmethane, 1,3- or 1,4-bis- (isocyanatomethyl) -cyclohexane, bis- (4-isocyanato-3-methyl) Cyclohexyl) methane, 1,
3-or 1,4-α, α, α′α′-tetramethylxylylene diisocyanate, 2,4-or 2,6
-Diisocyanatotoluene, 2,2'-, 2,4'- or 4,4'-diisocyanatodiphenylmethane (M
DI), 1,5-naphthalene diisocyanate, p- or m-phenylene diisocyanate, xylylene diisocyanate or diphenyl-4,4'-diisocyanate. Among these, the use of an aromatic diisocyanate compound is preferable from the viewpoint of mechanical strength, and the use of an aliphatic or alicyclic diisocyanate compound is preferable from the viewpoint of durability and light resistance. .

The isocyanate content with respect to the final solid content of the aqueous urethane resin is preferably in the range of 8 to 30%. Within this range, the cohesive force of urethane molecules is in a suitable range, and high adhesive strength can be exhibited.

Next, as the hydrophobic resin (B) used in the present invention, for example, polyurethane resin, polyester resin, polyacrylic resin, polyethylene resin, polypropylene resin, polyether resin (polypropylene glycol, polytetramethylene glycol, etc.) One or more compounds selected from the above, and / or at least 2
Copolymer compounds composed of more than one kind can be mentioned. Among them, it is particularly preferable to use polyurethane resin from the viewpoint of wide adhesiveness and the like, and polyester resin, polyacrylic resin, polyethylene resin, polypropylene resin and polyether resin are preferable from the viewpoint of cost. In consideration of the reaction with the hydrophilic urethane prepolymer (A), the hydrophobic resin (B) preferably does not contain a primary amino group and / or a secondary amino group. When a polyurethane resin is used as the hydrophobic resin (B), basically, a polyurethane resin in which no isocyanate group remains is used, but even if a polyurethane resin containing some isocyanate group remaining at the time of production is used. I do not care.

The number average molecular weight of the hydrophobic resin (B) used in the present invention is preferably 500 to 20,000.
Is more preferably in the range of 800 to 20,000, and in such a range, the cohesive force of the resin is moderated moderately and the heat resistance is in a suitable range. The number average molecular weight referred to here is GPC (gel permeation chromatography, measuring model: Tosoh High Speed GPC HLC-822) using tetrahydrofuran (THF) as an eluent.
It is a value obtained from the calibration curve prepared by using standard polystyrene measured in 0).

The ratio of the hydrophilic urethane prepolymer (A) and the hydrophobic resin (B) to be complexed in the present invention is preferably (A) / (B) = 99 / 1-40 / 60 (weight of solid content). Ratio), and more preferably 95/5 to 50/50 (solid content weight ratio). Within such a range, stable particle formation is possible without impairing water dispersibility, the cohesive force of the resin is in a suitable range, and the initial adhesiveness when processed at a low temperature is improved.

When preparing the aqueous polyurethane resin dispersion of the present invention, considering the formation of fine particles during emulsification and the elimination of residual solvent contained in the aqueous polyurethane dispersion of composite type after desolvation, a boiling point of 150 ° C. It is desirable to use the following organic solvents. The boiling point that can be used in the present invention is 1
Specific examples of typical organic solvents at 50 ° C or lower include benzene, toluene, ethyl acetate, acetone, methyl ethyl ketone, diethyl ether, tetrahydrofuran, methyl acetate, acetonitrile, chloroform, methylene chloride, carbon tetrachloride, 1,2- Dichloroethane,
Examples thereof include 1,1,2-trichloroethane and tetrachloroethylene, which may be used alone or in a mixed solvent. Among them, it is preferable to use acetone, methyl ethyl ketone, ethyl acetate, or toluene as a solvent having a high solubility in the polyurethane resin, alone or as a mixed solvent. In addition, N-methyl-
A solvent such as 2-pyrrolidone, ethyl cellosolve, n-butyl cellosolve, or propylene glycol methyl ether may be used in a content of 50% by weight or less based on the resin solid content.

An emulsifier may be used in combination when preparing the aqueous dispersion of the composite polyurethane resin of the present invention. Examples of typical emulsifiers usable in the present invention include polyoxyethylene polyoxypropylene glycol ether type,
Nonionic emulsifiers such as polyoxyethylene nonylphenyl ether type, polyoxyethylene octylphenyl ether type, polyoxyethylene laurate type, polyoxyethylene alkyl ether type, sorbitan derivative type, polyoxyethylene polycyclic phenyl ether type, alkylbenzene sulfone Anionic emulsifiers, cationic emulsifiers such as acid salt type and dialkyl succinate sulfonate type,
And zwitterionic emulsifiers.

Among these emulsifiers, nonionic emulsifiers,
And / or anionic emulsifier is suitable, and the content of the emulsifier is preferably 1 based on the solid content of the polyurethane resin.
It is 0% or less. When these emulsifiers are used, it is preferable to add them to the polyurethane solution before the emulsification / dispersion step or the prepolymer in which the isocyanate groups remain, and then to perform the emulsification / dispersion, but they may be added after the completion of the emulsification / dispersion step.

If necessary, a urethanization catalyst can be used when preparing the aqueous polyurethane resin dispersion. As a typical example of the urethanization catalyst,
Examples thereof include various nitrogen-containing compounds such as triethylamine, triethylenediamine, and N-methylmorpholine, various metal salts such as potassium acetate, zinc stearate, and tin octylate, and various organometallic compounds such as dibutyltin dilaurate.

The water-based adhesive and water-based coating agent of the present invention are characterized by containing the composite type polyurethane resin aqueous dispersion of the present invention. As the water-based adhesive and water-based coating agent of the present invention, the polyurethane resin may be used alone, but an aqueous dispersion other than the polyurethane resin represented by SBR latex resin and acrylic emulsion may be used as the polyurethane resin solid content / total solid content. The ratio is preferably in the range of 1 to 100% by weight, more preferably 10
You may use together in the range of up to 100% by weight.

Further, auxiliary materials and additives such as plasticizers and tackifiers (rosin resin, rosin resin, etc.) used for ordinary adhesives within the range of not impairing the cohesiveness of the aqueous adhesive and the aqueous coating agent of the present invention. It is also possible to use rosin ester resin, terpene resin, terpene phenol resin, petroleum resin, coumarone resin, etc.), fillers, pigments, thickeners, defoamers, antioxidants, UV absorbers, flame retardants, preservatives, etc. It is possible.

The aqueous dispersion of the composite type polyurethane resin can be used alone, but for the purpose of further improving durability, such as an amino resin, an epoxy compound, an aziridine compound, a carbodiimide compound, an oxazoline compound and a polyisocyanate compound. A bifunctional or higher functional compound may be used as the crosslinking agent. Among these, polyisocyanate compounds are preferable, and they can be used in the range of 0 to 50% by weight based on the solid content of the polyurethane resin.

Typical examples of the above polyisocyanate compound include 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate,
4,4'-diisocyanatodiphenylmethane (MD
I), a polyisocyanate compound consisting of a trimer such as xylylene diisocyanate, isophorone diisocyanate, or the polyisocyanate compound and ethylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, polyoxyethylene glycol, long chain Examples thereof include compounds having an isocyanate group terminal composed of a low molecular weight active hydrogen compound such as a higher alcohol.

[0046]

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. In the following, all "parts" and "%" are based on weight unless otherwise specified. The performance evaluation method for the adhesive and coating agent of the composite polyurethane resin aqueous dispersion of the present invention is as follows.

[Evaluation Method of Initial Adhesion Strength] Two adhesive base materials (evaluated with two kinds of vulcanized rubber sheet and polyvinyl chloride sheet) were used to apply the adhesive of the polyurethane resin water dispersion with a brush.
After applying 100 g / m ² to an adhesive substrate of mm (thickness) × 20 mm (width) × 300 mm (length), it is placed in a hot air circulation dryer at 50 ° C. for 6 minutes to be reactivated. The adhesive surfaces of the adhesive base material taken out from this dryer were pressed against each other with a rubber roller to bond them, and the peel strength 2 minutes after the bonding was measured with a digital gauge.

[Evaluation Method of Peeling Strength with Time] With respect to the bonded test piece prepared in the same manner as in the case of evaluating the initial adhesive strength, the peeling strength after bonding for 2 hours and after bonding for 1 day was measured by a tensile tester. The 180-degree peel strength was measured under the measurement conditions of a speed of 100 mm / min.

[Evaluation Method of Heat-resistant Creep Property] A laminated test piece prepared in the same manner as in the case of evaluating the initial adhesive strength was cured and cured at room temperature for 3 days. A 1 kg weight was hung on the test piece and placed in a hot air circulation dryer at 70 ° C. for 30 minutes to perform a heat resistant creep test in the 180 ° direction.
The distance (mm) at which 100 mm marked lines were peeled off, or the time when the weight fell was measured.

Reference Example 1 Preparation of Polyester Polyol (1) Containing Aromatic Sulfonate Metal Base While introducing nitrogen gas into a reaction vessel equipped with a thermometer, a nitrogen gas introducing tube, and a stirrer, 5-sulfosodium 1480 parts of dimethyl isophthalate (DMS) and 1240 parts of 1,6-hexanediol, and dibutyltin oxide 0.5.
And the acid value of the reaction product was 1 mg at a reactor internal temperature of 180 to 190 ° C. so that the tower top temperature was 60 to 70 ° C.
The transesterification reaction is performed until KOH / g or less (the unit is omitted below), and then the reaction is performed at 210 ° C. for 2 hours. Then, after cooling to 100 ° C., ε-caprolactone 22
80 parts of the resulting mixture was subjected to a ring-opening polymerization reaction at 180 ° C. for 3 hours to obtain a polyester polyol (1) having a hydroxyl value of 120 and an acid value of 0.3 as shown in Table 1.

[0051]

[Table 1]

Reference Example 2 Preparation of Hydrophobic Resin (U) 100 parts of polyester (hydroxyl value = 37.4) consisting of 1,4-butylene glycol and adipic acid, 3 parts of neopentyl glycol, and 55 parts of methyl ethyl ketone. Was added and sufficiently stirred to dissolve, 12 parts of hexamethylene diisocyanate was added, and the reaction was carried out at 80 ° C. for 3 hours. Next, after 28 parts of methyl ethyl ketone was added and cooled to 60 ° C., 10 parts of a polyester (hydroxyl value = 190) consisting of 1,4-butylene glycol and adipic acid was added, and 80 ° C. was added until the isocyanate value became less than 0.1%. To obtain a urethane type hydrophobic resin (U) having a non-volatile content of 60% and a number average molecular weight of 15,000.

100 parts of polyester (hydroxyl value = 37.4) consisting of 1,4-butylene glycol and adipic acid, 3 parts of neopentyl glycol and 79 parts of methyl ethyl ketone were added and sufficiently stirred to dissolve, and 15 parts of hexamethylene diisocyanate was added. Was added and reacted at 80 ° C. for 3 hours. Then, the reaction is carried out at 80 ° C. until the isocyanate value becomes 1.15% or less, and the hydrophobic urethane prepolymer (U- having a nonvolatile content of 60% and a number average molecular weight of 4,000) is used.
P) was obtained.

Example 1 50 parts of the polyester polyol (1) obtained in Reference Example 1 and 90 parts of methyl ethyl ketone were thoroughly stirred and dissolved, 55 parts of isophorone diisocyanate (abbreviated IPDI) was added, and the mixture was stirred at 80 ° C. for 3 days. Reacted for hours. Next, methyl ethyl ketone (abbreviation MEK) 15
After adding 0 part and cooling to 60 ° C., 1 part neopentyl glycol and 255 parts polyester (hydroxyl value = 56.1) consisting of 1,4-butylene glycol and adipic acid were added and reacted at 80 ° C., Isocyanate value is 0.7
When it became 9% or less, it was cooled to 50 ° C. to obtain a hydrophilic urethane prepolymer. In addition, the hydrophobic resin obtained in Reference Example 2
Add (U) 150 parts and mix uniformly. Then water 52
After adding 5 parts and emulsifying and dispersing, 10% piperazine aqueous solution 4
3.8 parts (90 equivalent% as an amine group with respect to the residual isocyanate group) was added and emulsified and dispersed. The obtained emulsion was desolvated to obtain an aqueous dispersion having a nonvolatile content of 50%. SN-thickener was added to 100 parts of the obtained water dispersion.
After adding 1 part of A-812 (manufactured by San Nopco Ltd.) to increase the viscosity, an isocyanate crosslinking agent CR- that can be dispersed in water
The adhesive was adjusted by adding 5 parts of 60N (manufactured by Dainippon Ink and Chemicals, Inc.). The compounding composition is summarized in Table 2. Next, the adjusted adhesive was applied to two PVC sheets with a brush at 100 g / m ² , and the adhesive surfaces were adhered to each other to evaluate each adhesive performance. The adhesive after brush coating showed a uniform film thickness, and as shown in Table 3, the adhered substrates were excellent in adhesive strength and heat resistance in both the PVC substrate and the rubber substrate.

Comparative Example 1 As shown in Table 2, Example 1
The same operation as in Example 1 was carried out except that the hydrophobic resin (U) was used to obtain an aqueous dispersion having a nonvolatile content of 50%. An adhesive was prepared from the obtained water dispersion in the same manner as in Example 1. Then, the adhesive surfaces were adhered to each other and each adhesive performance was evaluated. Both the adhesive strength and the heat resistance were relatively good, but the adhesive strength and the heat resistance were not sufficient in the rubber base material in which the base material temperature was hard to rise.

Comparative Example 2 As shown in Table 2, Example 1
The same operation as in Example 1 was carried out except that the amount of the hydrophobic resin (U) used in Example 1 was changed to 1116 parts, but the particle stability after emulsification was poor and, as a result, aggregation occurred.

Comparative Example 3 As shown in Table 2, Example 1
Hydrophobic urethane prepolymer resin (UP) instead of hydrophobic resin (U)
Add 50 parts and mix evenly. Next, 525 parts of water was added and the mixture was emulsified and dispersed.
Part (90 equivalent% as an amine group relative to the residual isocyanate group) was added and emulsified and dispersed. The obtained emulsion was desolvated to obtain an aqueous dispersion having a nonvolatile content of 50%. An adhesive was prepared from the obtained water dispersion in the same manner as in Example 1. Then, the adhesive surfaces were adhered to each other and each adhesive performance was evaluated. Both the adhesive strength and the heat resistance were good, but in the rubber base material in which the temperature of the base material was unlikely to rise, the heat resistance was good, but the adhesive strength was not sufficient.

[0058]

[Table 2]

In Table 2, Mw means weight average molecular weight and Mn means number average molecular weight.

[0060]

[Table 3]

[0061]

EFFECT OF THE INVENTION The present invention provides an aqueous dispersion of a composite polyurethane resin which is excellent in processability under low temperature conditions of 80 ° C. or lower and solves adhesiveness to a wide range of substrates.
We provide polyurethane water-based adhesives and water-based coatings that have excellent adhesive properties immediately after lamination and after aging, and also have excellent heat resistance. Rubber, leather, metal, polyvinyl chloride
It can be widely used for adhesion and surface modification of various substrates such as plastics such as (PVC) and foams.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C09J 175/04 C09J 175/04 201/00 201/00 F term (reference) 4J002 BB02X BB11X BG04X CF00X CH01X CK02W CK02X GH00 HA06 4J038 CB021 CB022 CB081 CB082 CG141 CG142 DD001 DD002 DF021 DF022 DG051 DG052 DG061 DG062 DG111 DG112 DG121 DG122 DG131 DG132 GA06 GA11 GA13 MA08 MA10 MA14 NA12 NA14 4J040 DA021 DA022 DA101 DA102 DF041 DF042 ED001 ED002 EE021 EE022 EF051 EF052 EF061 EF062 EF111 EF112 EF121 EF122 EF131 EF132 GA07 GA20 GA25 JA03 LA06 LA08

Claims (5)

[Claims] 1. A self-emulsifying hydrophilic urethane prepolymer containing a terminal isocyanate group (A) and a hydrophobic resin (B) having a number average molecular weight in the range of 500 to 20,000. Composite polyurethane resin aqueous dispersion. 2. The ratio of the hydrophilic urethane prepolymer (A) and the hydrophobic resin (B) is (A) / (B) = 99/1.
The composite type polyurethane resin aqueous dispersion according to claim 1, wherein the composite type polyurethane resin aqueous dispersion is about 40/60 (solid content weight ratio). 3. The composite polyurethane resin aqueous dispersion according to claim 1, wherein the hydrophilic urethane prepolymer (A) has, as a hydrophilic group, an anionic group, or an anionic group and a nonionic group. 4. An aqueous adhesive containing the composite polyurethane resin aqueous dispersion according to claim 1. 5. A water-based coating agent comprising the composite type polyurethane resin aqueous dispersion according to claim 1.