JPS60212455A - Production of aqueous resin - Google Patents

Abstract

PURPOSE:To produce an aqueous resin usable for odorless adhesives having improved adhesive properties, by incorporating a specific aqueous polyurethane resin with a polyfunctional epoxy compound. CONSTITUTION:(A) 100pts.wt. water-soluble or water-dispersible urethane polymer obtained by adding an organic diisocyanate, e.g. xylylene diisocyanate, to a compound having 200-4,000 average molecular weight and 2 active hydrogen atoms, e.g. polyether or polyester, crosslinking the resultant prepolymer having isocyanate groups at the terminal positions with a chain extender, preferably an alkanolamine having tertiary nitrogen atom such as N-methyldiethanolamine alone or together with ethylene glycol, and neutralizing or making the resultant product cationic is incorporated with (B) 0.5-20pts.wt. polyfunctional epoxy compound, e.g. (poly)glycidyl ether.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a water-based resin for use in adhesives.

Water-based resins have traditionally been used in a wide variety of applications, including as coatings and binders for fibers, paper, leather, metals, wood, etc., as well as adhesives, pastes, paints, and floor polishes.

Conventional water-based resins used in adhesives include synthetic rubber latex, vinyl acetate emulsion, acrylic emulsion, ethylene acetate emulsion, polyvinyl alcohol, and other synthetic or natural starches, but each has its own characteristics. is used effectively. Adhesives using the water-based resin obtained by the method of the present invention can be used in fields where improved peel strength is particularly required by improving performance by blending with other water-based resins.

When the aqueous resin obtained by the method of the present invention is applied to laminates, especially to foods that are packed using laminate films due to changes in dietary habits, food products have diversified and the adhesive used in the production of laminate products has increased accordingly. The performance of agents is becoming more important.

However, at present, solvent-based adhesives are used because the adhesive performance of water-based resins is low. For this reason, in addition to saving resources and energy, a large amount of heat source is required to remove the solvent, and it takes a considerable amount of time to show initial wJ adhesion. In addition, the volatilization of this solvent is unfavorable in terms of working environment hygiene.Furthermore, a considerable amount of solvent remains in the laminated product after bonding, which not only causes peeling, but also causes food hygiene problems and odor adhesion. There was an urgent need to solve these problems.

As a result of extensive research to solve these problems, the inventors of the present invention have found that they are odorless without the use of solvents, and have adhesive strength that exceeds that of solvent-based resins, which was not possible with conventional water-based resins. I was able to obtain

The present invention involves the addition reaction of an organic diisocyanate to a compound having two active hydrogen atoms having a molecular weight of 200 to 4000, and a prepolymer having an incyanate group at the terminal position, which is further subjected to a crosslinking reaction with a chain extender having a molecular weight of 300 or less. The present invention relates to a method for producing a water-based resin, which is characterized in that a polyfunctional epoxy compound (B) is blended into a water-based polyurethane resin in which the obtained product is dissolved or dispersed in neutralized drained water.

The compounds having two active hydrogen atoms in the average molecular weight used in the production of the aqueous polyurethane resin (A) component used in the present invention are those used as raw materials for the production of general urethane products, such as polyols, Polyesters, polyester amides, polyethers, etc. can be used. Examples of polyethers include compounds obtained by addition polymerization of ethylene oxide, propylene oxide, butylene oxide, tetrahydrofuran, etc., to a compound having active hydrogen such as water, glycerin, trimethylolpropane, and water.

Examples of polyesters include ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, bentanediol, hexanediol, octanediol, 2-ethyl 1,3-hexanediol, and bisphenol A1. It is obtained by condensation of saturated and unsaturated low molecular weight glycols such as diethylene glycol and dipropylene glycol with tribasic acids. In addition, hexamethylene-based and caprolactone-based glycols, polythioethers, and polyacetals can also be used. If the average molecular weight of these compounds having two active hydrogen atoms in the molecule is less than 200, no adhesive force will be obtained, and if it is greater than 4000, the adhesive will be strong and the peel strength at 80° C. will be seriously reduced.

Examples of the organic diisocyanate used in the present invention include aromatic, aliphatic, and alicyclic diisocyanates, such as 1.5-naphthene diincyanate, 4.4'-
Diphenylmethane diisocyanate, 4,4'-diphenylmethylmethane diisocyanate, di- and tetraalkyldiphenylmethane diisocyanate, 4,4'-dibenzyl diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, toluylene diisocyanate, inphorone diisocyanate , 1.41 butylene diisocyanate, I, 6-benzene diisocyanate and xylylene diisocyanate, and the chlorinated diisocyanates and brominated diisocyanates of these diisocyanates can be described as equivalents.

In addition, alkanolamines having a tertiary nitrogen having a molecular weight of 300 or less can be used as chain extenders, such as N-methylgetanolamine, N-ethylgetanolamine, 1N-ole-ilgetanolamine alone, or these amines and ethylene. Glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, 1.3-phthylene glycol, tetramethylene glycol, hexamethylene glycol, 1.4
-Butanediol, neopentyl glycol, etc. are used in combination.

Examples of polyfunctional epoxy compounds include diglycidyl ethers of glycols and polyglycidyl ethers of polyols. Compounds that can be used in combination with these include diglycidyl esters and monoglycidyl ethers of dicarboxylic acids, bisphenol-type epoxy resins, and polyhydric epoxy resins. Examples include phenol epoxidized products and olefin epoxidized products. Regarding diglycidyl ether of glycols and polyglycidyl ether of polyols, for example, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1 , 6-hexanesiol diglycidyl ether, dibromoneopentyl glycol diglycidyl ether, glycerol polyglycidyl ether, trimethylolpropane polyglycidyl ether,
Examples include diglycerol polyglycidyl ether, polyglycerol polyglycidyl ether, and sorbitol polyglycidyl ether.

In these uses, the polyfunctional epoxy compound shown here is an epoxy compound having trifunctional or more functional epoxy groups in one molecule.

The present invention will be explained below using examples and examples.

Normally, the prepolymer production reaction is performed because it is easy to check the process. A pre-prepolymer is synthesized by reacting 1.1-3.0 equivalents of organic diisocyanate with one hydroxyl group of the polyol used. At this time, C of the polyol
The lower the PR, the better.

(The CPH measurement method is based on JISK-1557) The reaction temperature is 3G-150℃ and the time is from several hours to 10
The reaction is usually carried out over several hours, and the reaction is continued by adding 0.5 to 1.5 equivalents of chain extender to each remaining incyanate group. Since the reaction system increases in viscosity during this process, a solvent can also be used if necessary.

To remove the used solvent in the final process, a topping operation is performed as necessary.

Although this chain extender can be used in combination with A41, in the present invention, it is preferable to use a chain extender having at least tertiary nitrogen in the molecule alone or in combination with another chain extender.

After the crosslinking reaction is completed, it can be neutralized or cationized with an organic or inorganic acid to obtain a water-soluble or water-dispersible urethane polymer.

The resulting water-soluble or water-dispersible urethane polymer may be mixed with various surfactants, leveling agents, thickeners, preservatives, etc. as required (7JI) and other water-based resins to form a composite type. It is used according to the purpose.

The present invention will be concretely explained below with reference to dragon manufacturing examples and examples.

Construction example 1 Polyether polyol P-400 was added to the reaction equipment, 40
After preparing 01r, add xylylene diincyanate 3 to this.
I prepared 80#r. When initially heated to 40℃, there was a slight exothermic reaction, so while cooling as necessary, the reaction temperature was increased to 75-80℃.
It took about 4 hours and 30 minutes for the reaction product to have a calculated value of 1097 degrees Celsius.

Add 85 jlr of N-methyljetanolamine and 19NF of ethylene glycol, and reduce the reaction temperature to 60-65
It was kept at ℃. Incyanate group (
230G Kaiser) while confirming the decrease,
As the contents became highly viscous, 100 lr of acetone was added to continue the reaction, and when the absorption of incyanate groups had almost disappeared, 26k acetic acid was dissolved in 1001r water and added, so that the resin content became 30-. Water was added, stirred thoroughly at 80° C. for 2 hours, topped with acetone, and then cooled to obtain a water-based urethane resin.

Table 1 shows the manufacturing recipe and raw material composition table for an example of ridge formation of water-based urethane resin.

Table 1 Number li [2 units are Durham note, l Adeka Ace Y-4-605 manufactured by Asahi Denka Kogyo ■ 2
Plaxel 220; 3T, D manufactured by Daicel Chemical Industries ■
, I) Lylene diisocyanate X, D, I Xylylene diisocyanate H, M, D, I shows.

gGDGE i Ethylene glycol diglycidyl ether GPGE i Glycerol polyglycidyl ether 5PGE: Sorbitol polyglycidyl ether evaluation method 1, peel strength [cpp, 'opp film each resin 20
% aqueous solution and coated with wire bar No. 3 at 40°C.
Measurement width after day and night: 15m Intensity unit! 2. Water resistance Apply adhesive in film form, 110℃ x 3
After drying for a while, a spot test with water drops was performed and the evaluation was 0. No change. △Whitening x Dissolution.

QNo abnormality in adhesive ΔSlightly incomplete In addition, this water-based resin has excellent stability over time, and its curing properties can be adjusted by using a catalyst, giving it excellent practical properties not found in conventional products. Recognize.

Patent applicant: Toho Chemical Industry Co., Ltd.

Claims (1)

[Claims] (1) A prepolymer having an incyanate group at the terminal position obtained by adding an organic diisocyanate to a compound having two active hydrogen atoms having an average molecular weight of 200 and -4000 is further subjected to a crosslinking reaction with a chain extender having a molecular weight of 300 or less. 1. A method for producing a water-based resin, which comprises neutralizing the product obtained by neutralizing the product, and then blending a polyfunctional epoxy compound into a water-based polyurethane resin that has been dissolved or dispersed in water. (2. 0 parts of polyfunctional epoxy compound per 100 parts of the resin content of the water-based polyurethane resin described in claim 1)
．． A method for producing a water-based resin adhesive characterized by blending 5-20 parts.