JPS6026433B2 - Pressure-sensitive adhesive composition for surface protection materials for aesthetic surfaces - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pressure-sensitive adhesive composition for use as a surface protection material for mounting surfaces such as synthetic resin boards, hardboard boards, metal plates, plywood, and the like.

Natural latex pressure-sensitive adhesives, which have been widely used in the past, have poor weather resistance, and are prone to "rubber fatigue" due to exposure to sunlight, etc., increase in peel strength, increase in adhesive strength due to temperature and humidity, and even cause significant damage to the adhesive surface. This has the drawback of contaminating the material, causing a "cold" phenomenon due to a drop in temperature and humidity, and causing poor adhesion. Although various acrylic pressure-sensitive adhesives have been investigated to improve these drawbacks, no satisfactory pressure-sensitive adhesive composition has been obtained. Therefore, in the present invention, it is an object of the present invention to solve the above-mentioned conventional drawbacks and to provide a composition suitable as a pressure-sensitive adhesive composition for surface protection materials for mounting surfaces such as synthetic resin boards, fixed name boards, metal plates, plywood, etc. and
Its feature is that it is made by adding an appropriate amount of amines as a crosslinking agent to a water-dispersed emulsion consisting of the following components.

Acrylic acid or methacrylic acid alkylester having an alkyl group containing 6 to 12 carbon atoms [2
1 Acrylic acid or methacrylic acid alkyleste/shitsukuda functional monomers with alkyl groups containing up to 5 carbon atoms 1'31 N-methylolalkylolamide of acrylic acid or methacrylic acid '41 Glycidyl acrylate and glycidyl methacrylate '5 'Allyl glycidyl ether'c} functional monomer [61 } Preferred polymerization ratios of the above-mentioned components [11 to '6] as component 'q' can be exemplified as follows.

Song - Any one or several of [Su4)'5)...1.0
~20% [C)-'6}...2.0-15.0%
(% by weight) In addition, in practice, for the monomer having the composition consisting of the above-mentioned [B}{q component, an anionic/ionic mixed activator is used as an emulsifier, and a persulfate is used as a polymerization initiator. ,
Emulsion copolymerization using water as dispersed soot.

An appropriate amount of amines is added as a crosslinking agent to the polymer emulsion thus obtained. These amines include 'a} aliphatic polyamines such as diethyl polyamine, triethylene tetracine, polymethylene diamine, tetraethylene bentamine,
N,N as diethylaminopropylamine, N-aminoethylpiverazine, m-xylylenediamine, polymethylenediamine, polyetherdiamine, menthanediamine, N-aminoethylpiverazine, m-xylenediamine or modified aliphatic polyamine '-bishydroxyethyl, N,N'-bishydroxypropyl and the like can be enumerated.

'b-Aromatic amines such as m-phenylenediamine, diaminophenol ether, 4,4'-methylenediamine, diaminodiphenyl sulfone, benzidine, toluidine, 4,4'
Examples include -thiodianiline, 0-phenylenediamine, dianisidine, ○-chloroaniline, 2,4-toluenediamine, diaminoditolylsulfone, 4-chloro0-phenylenediamine, and m-aminobenzylamine.

'c - Secondary and tertiary amines For example, secondary amines include N-methylpiverazine, hydroxyethylpiverazine, piperazine, pyrrolidine, and morpholine, and tertiary amines include linear diamines,
Tetomethylguanidine, triethanolamine, N,N
, N',N'-tetramethyl-1,3-butanediamine, N,N'-dimethylpiveradiso, hexamethylenetetracine, pyridine, pyrazine, quinoline, penzyldimethylamine, Q-methylbenzylmethylamine, etc. .

The most characteristic feature of the adhesive composition according to the present invention produced as described above is {i' Crosslinking of carboxylic acid and alkylolamide '01 Crosslinking of alkylolamides with each other In this case, the remaining polymerization initiator NAC1, p-toluenesulfonic acid, etc. act as a persulfate or a catalyst to cause a radical reaction and an acidic condensation reaction, thereby significantly increasing the crosslinking rate.

Crosslinking between a monocarboxylic acid and an epoxy group In this case, an acidic catalyst such as p-toluenesphonic acid acts as a catalyst to significantly increase the crosslinking rate.

An emulsion of a highly elastic polymer composition obtained by a crosslinking reaction in combination of at least two of the four types of crosslinking between an epoxy group and the above-mentioned amines is used as a pressure-sensitive adhesive composition. can.

Further, basic monomers in the composition according to the present invention include hexyl acrylate, n-octyl acrylate, isooctyl acrylate, 2-ethylhexyl acrylate, and dodecyl acrylate as acrylic acid or methacrylic acid alkyl esters having 6 to 12 carbon atoms. , decyl acrylate or their methacrylates.

Bentyl acrylate, n as a monomer of acrylic acid or methacrylic acid alkyl esters having 5 or less carbon atoms
-butyl acrylate, inbutyl acrylate, ethyl acrylate, methyl acrylate, or their methacrylates.

The preferred proportion of acrylic acid alkyl esters or acrylic acid meta-alkyl esters is 70 to 90% (wt%), and within that range, the alkyl group has 6 to 1 carbon atoms.
The monomers of No. 2 and monomers having 5 or less alkyl groups are coarsely combined and adjusted to an appropriate glass transition temperature. When a large amount of monomers having carbon number of 5 or less is used, the glass transition temperature becomes high.
Not suitable for use in protective adhesive sheets. In addition, a large amount of alkyl groups having 6 to 12 carbon atoms is used, and 5 to 5 carbon atoms are used.
The amount of copolymerizable vinyl monomers that can partially replace the following alkyl esters of acrylates, and polymers with a glass transition temperature of 30 to 10, such as vinyl acetate, styrene, and acrylonitrile, is 5. % by weight or less.

Examples of the cross-curing monomer include N-alkylolamide of acrylic acid or methacrylic acid, glycidyl acrylate,
Glycidyl methacrylate, furyl glycidyl ether.

Examples of the N-alkylolamides include N-methylol acrylamide, N-ethylol acrylamide, N-propanol acrylamide, N-tertbutylacrylamide, and diacetone acrylamide. Among these monomers, N-methylol acrylamide, glycidyl methacrylate, and glycidyl acrylate exhibit preferable effects. Monomers effective as Q-olefin type carboxylic acids include acrylic acid, methacrylic acid, itaconic acid, and the like.

As effective monomers that can be added to the emulsion as a crosslinking agent, ethylene diamine, triethylene thitramine, jethylene triamine, etc. are most commonly used as iamines for room temperature curing.

(b) Examples of persulfates and acidic catalysts include potassium persulfate, ammonium persulfate, ammonium chloride, diammonium phosphate/P-toluenesulfonic acid, amine hydrochloride, and the like.

When the polymer composition constructed according to the present invention is used as a pressure-sensitive adhesive composition for a protective adhesive tape based on paper or synthetic resin film, it can be used as an adhesive part that can sufficiently adhere. Applications become possible.

This adhesive part can be easily adhered to the surface of synthetic resin boards such as acrylic boards, decorative boards, metal boards, plywood, etc. to protect the surface, and may cause natural peeling due to climate changes or It has the characteristics of having stable peel strength without increasing the adhesion strength and not contaminating the adherend having a beautiful diamond surface. Examples of the present invention will be described below along with comparative examples using natural rubber latex.

(Parts... Parts by weight) Comparative example 1 Natural rubber latex (solid content 60%) 16 parts As an anti-aging agent 2
, 2 parts of 3,4 trimethyl-1,2 dihydroquinoline,
A pressure-sensitive adhesive composition made of natural rubber or the like was prepared containing 3% of a fungicide (phenol, etc.), 0.4 parts of a tackifier (acrylic, etc.), and 18 parts of ammonia.

Comparative Example 2 Emulsion copolymerization of 2-ethylhexyl acrylate 10-base, 25.5 parts of n-butyl acrylate, and 4.5 parts of glycidyl methacrylate was carried out in the same manner as in Example.

and ethylenediamine2. Add Guo. However, the above component) is missing. Example 1 2-ethylhexyl acrylate 1, n-phthyl acrylate 2
4.5 parts of glycidyl methacrylate, 35 parts of methacrylic acid, and 2.15 parts of methacrylic acid were polymerized in a conventional manner to form an emulsion, and 0.5 parts of ethylenediamine was added. Add the $ portion carefully.

Example 2 To an emulsion identical to the formulation of Example 1 is added 1.8 parts of ethylenediamine.

Example 3 In the same emulsion as in Example 1, 1. Add part of.

Example 4 2-ethylhexyl acrylate 15. $ parts, n-phthyl acrylate 17. Yuibe, glycidyl methacrylate 4.8 parts, methacrylate 3. The private part was subjected to emulsion copolymerization in the same manner as in Example 1.

Two parts of diethylenetriamine are then added to the emulsion. The emulsions obtained in Comparative Examples 1 and 2 and Examples 1 to 4 were left in a 20 oo room for 6 to 10 days to complete the crosslinking reaction. Then, the obtained emulsion was applied directly to kraft paper (36 ml/end), dried, and left indoors for 2 hours under the conditions of 20 qo and 60% RH.

The physical property values of each are listed below.

Dirty, degree rank: ○... Not visible to the naked eye △…… 8 good / a little ×……Bright with the naked eye 〔remarks〕 Test method a It was conducted according to JIS-C2107.

b Peeling strength unit... evening/5W c Peeling speed...30Q cape/mind Peeling body... Acrylic board As is clear from the test method above, this invention In this case, no increase in staining property or peel strength was observed.

Claims (1)

[Claims] 1. Surface protection for aesthetic surfaces, characterized by adding an appropriate amount of amines as a crosslinking agent to a water-dispersed emulsion consisting of the following three components (A), (B), and (C). Pressure sensitive adhesive composition for materials. (A) Main component monomer (1) Acrylic acid or methacrylic acid alkyl ester having an alkyl group containing 6 to 12 carbon atoms (2)
Acrylic acid or methacrylic acid alkyl esters (B) functional monomers with alkyl groups containing up to 5 carbon atoms (3) N-methylolalkylolamide of acrylic acid or methacrylic acid (4) Glycidyl acrylate and glycidyl methacrylate (5) ) Allyl glycidyl ether (C) functional monomer (6) α-olefin carboxylic acid [However, for (3), (4), and (5), any of them may be used alone or in an appropriate combination of several]