JPS58109572A - Pressure-sensitive adhesive composition - Google Patents

Abstract

PURPOSE:To provide a pressure-sensitive adhesive compsn. which little suffers deterioration of adhesion with time, by blending an acrylic copolymer resin, a resol type phenolic resin and a polyfunctional isocyanate compd. CONSTITUTION:100pts.wt. acrylic copolymer consisting of 60-99wt% 1-18C alkyl acrylate, 1-10wt% alpha,beta-ethylenically unsaturated carboxylic acid and 0- 39wt% other vinyl monomer, 3-30pts.wt. resol type phenolic resin, 5-50pts.wt. xylene resin, 0.01-10pts.wt. at least one member selected from a polyfunctional isocyanate compd., an alkyletherified melamine resin and a metal chelate compd., and 0-30pts.wt. tackifying resin are blended together.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to new and useful pressure sensitive adhesive compositions.

Conventionally, acrylic-based adhesives have been used as pressure-sensitive adhesives, but products using this adhesive, such as adhesive sheets or adhesive tapes, are manufactured using soft polyvinyl chloride sheets (hereinafter referred to as soft polyvinyl chloride sheets). When used for adhesion or lamination of polyvinyl chloride (abbreviated as PVC sheet), after such lamination, the low-molecular plasticizer in this polyvinyl chloride migrates to the adhesive layer, causing softening of the adhesive. Furthermore, the adhesive strength itself deteriorates, which is a significant change over time, making it unsuitable for practical use.

However, as a result of intensive research by the Ministry of Invention and others to resolve the drawbacks of conventional adhesives as described above, they have discovered an adhesive whose adhesive strength decreases significantly over time compared to conventional adhesives. So, complete the non-invention [%11].

That is, the non-invention is the following specific copolymers N, resol-type phenol sideways B) and xylene hydroxides),
Polyfunctional isocyanate compound 'mDl, alkyl etherified melamine a (Chue E) or metal chelate compound IMF
I is an essential component, and further, depending on the necessity, a tackifying tree (11 KG) is added to acrylic acid alkyl ester having an alkyl group of C7 to CI8 in an amount of 60 to 99%, α,
1 to 101% of β-ethylenically unsaturated carboxylic acid,
0~39m! % of copolymerizable vinyl compound and 100 car front parts of copolymer N obtained by reacting with 6 to 30 parts of tree manure B) and tree manure C), respectively. Heavy scene part weight upper = aD), (smell or (F
The present invention provides a pressure-sensitive adhesive composition comprising 0.01 to 10 parts of the component 1 and, if necessary, 5 to 60 parts of mArashi GI. .

Here, the above-mentioned acrylic acid alkyl ester refers to the alcohol component constituting the ester having an alkyl group of C, to CI8, particularly preferably C8 to CI2, such as methyl acrylate, acrylic acid, etc. Typical examples include ethyl acrylate, n-propyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, and lauryl acrylate, and the amount used is 60 to 99% by weight in the copolymer. is preferred. 60 weight 7
If it is less than 0, its properties as an adhesive will be impaired, and conversely, if it is less than 99
If it exceeds %, the cohesive force will become too strong, which is undesirable.

Additionally, typical α,lf-type unsaturated carboxylic acids mentioned above include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, and maleic anhydride, and the amounts used are 1-10 during merging]1
i%, particularly preferably 6 to 8 M1%. moreover,
Typical vinyl compounds that can be copolymerized with each of the above monomers include styrene, vinyl acetate, vinyl propionate, acrylonitrile, and acrylamide, and the amount used in the copolymer ranges from 00 to 301.
However, it is not preferable that the amount exceeds 301% because it will lead to insufficient adhesiveness.

On the other hand, in order to obtain an adhesive especially suitable for soft PVC, a solid or bath liquid type resol type phenolic resin alB) is added to 100 parts by weight of the above-mentioned copolymer N.
5 to 30 parts by weight, and 5 to 5 parts of xylene tree 11dc+
0 parts by weight! It is necessary to add it within the range 5-. In other words, in order to obtain a pressure-sensitive adhesive with good plasticizer resistance, it is necessary to
The addition of both components is essential, and the desired performance cannot be obtained by adding only one of the two components at a single pressure.

The amount of the resol type phenolic resin B) added is 3 to 30 parts by weight per 100 iKf parts of the copolymer (Al);
Preferably, 5 to 15 parts by weight is appropriate; if it is less than 3 parts by weight, the effect of the present invention is not sufficient; on the contrary, if it is less than 3 parts by weight,
If the amount exceeds 0.1 part by weight, the properties of the resulting composition as a pressure-sensitive adhesive will be impaired. On the other hand, the amount of xylene (m) added is 5 to 503 parts per 1001 parts of the copolymer. i part, preferably 15 to 35 parts by weight, is appropriate; if it is less than 15 parts by weight, the adhesive force will be insufficient, and if it exceeds 50 parts by weight, the cohesive force will be insufficient. Both of these are undesirable, as they will lead to

6- These resol type phenol tree Bl:to' and xylene tree gmC) are obtained as follows, respectively, but in particular, the a'+Fi gmB) is 1
00% solid or Alcono Ginya type is preferred.

First, this MBI is based on phenols such as phenol, cresol, resorcinol, bisphenol A, or oligomers of phenol, and formaldehyde and its equivalent substances such as formaldehyde, paraformaldehyde, or hexamethylenetetramine. On the other hand, xylene & [fdQ is produced by a known and conventional method using xylene and the above-mentioned formaldehyde supplying substance as raw materials. or those modified with alkylphenol/l/ such as cresol.

The composition of the present invention is prepared by adding these resol type phenolic resins) and xylene resins to the above-mentioned copolymer, and if necessary, adding terpene/phenolic resin, rosin or hydrogenated rosin. Known and customary tackifiers such as esters or petroleum resins (G) may be added in an amount of up to 301f per 100 parts of the copolymer.

It is also necessary to add the above-mentioned polyfunctional incyanate compound -D), alkyl etherified melamine sotsuki 1dE) or metal chelate compound -F) to the composition of the present invention as a crosslinking agent component. Compound 'IIMD
) is a typical adduct of three molecules of tolylene diincyanate and one molecule of trimethylolpropane. Alcohols such as methanol and n-butanol can be obtained by known and conventional methods as raw materials, but typical examples include metals such as zinc, magnesium, titanium or aluminum, and compounds containing alkoxyl groups. Some are coordinated with organic substances such as acetylacetone and acetylacetone.

These Kirin-kaku 1'' components are 1001 of the above-mentioned Kyoei combined prisoners.
0.01-101 mass for the front, preferably 0.1
It is used in a range of 51 parts by weight. If it is less than 0.01' parts, no optical cross-linking effect can be expected; on the other hand, if it is more than 101 parts, the tackiness as a pressure-sensitive adhesive will inevitably be impaired. Undesirable.

The thus obtained uninvented composition can be used as a pressure-sensitive adhesive, not only for conventional applications, but also for soft PVC sheets, which cannot be achieved with conventional acrylic pressure-sensitive adhesives. It has an excellent adhesion effect when bonding or bonding adherends such as polyvinyl chloride, soft PVC, leather, etc.

Next, the present invention will be specifically explained using Examples and Comparative Examples. In the following, all parts and percentages are based on weight unless otherwise specified.

Example 1 2-ethylhexyl acrylate '50 parts n-butyl acrylate 67 parts acrylic acid
3-part benzoyl peroxide
0.3s ethyl acetate
130 parts of each of the above-mentioned compounds were charged into a reaction vessel, and the mixture was kept at 75-80°C for 10 hours without stirring in a nitrogen stream, and then 20 parts of toluene was added to terminate the reaction. The solution of the acrylic copolymer thus obtained had a non-volatile content of 398% and a viscosity (Gardner method, 25° C.; hereinafter the same) of about 5,000 cps and 10-.

Next, a solid resol type phenol resin (Inu Nippon Ink Chemical Co., Ltd.
1.
In addition, 1 part of Nicanol H-1 (xylene resin manufactured by Mitsubishi Gas Chemicals Q), 30 parts of Nicanol H-1 (xylene resin manufactured by Mitsubishi Gas Chemical Co., Ltd.), 1 part of melamine resin] was added, and the pressure-sensitive adhesive composition was then mixed with the resulting film and 5 parts of dibutyl phthalate as l'J Plastic 41.
A soft polyvinyl chloride sheet with a thickness of approximately 0.2 mm containing 4 PHR was laminated together, and changes in peel strength over time were investigated when the sheets were stored in atmospheres of 40° C. and 60° C., respectively. The results are summarized in Table 1.

Example 2 n-butyl acrylate 90 parts Vinyl acetate 5 parts acrylic acid
5 parts Azobisisobutyronitrile
0.3 parts ethyl acetate 1
00 parts Each of the above compounds was charged into a reaction vessel, and heated to 75 to 80°C for 8 hours while stirring in a nitrogen stream, and then
The reaction was completed by adding 50 parts of toluene. The nonvolatile content of the copolymer solution thus obtained was 697%, and the viscosity was 6.5%.
It was 00cps.

Next, for 100 parts of the solid content of this bath liquid, [Bryau7xnBA-5034110s1
20 parts of L J (xylene resin manufactured by Mitsubishi Gas Chemical Co., Ltd.), [
10 parts of YS Polyster T-130j (terpene/phenol resin manufactured by Yasushi Kogyo ■) and 1 part of Burnock D-7
A pressure-sensitive adhesive composition was obtained by adding 2 parts of 5DJ (polyisocyanate compound manufactured by Dainippon Ink & Chemicals Co., Ltd.).The performance was evaluated in the same manner as in Example 1, except that this composition was used. , the results shown in Table 1 were obtained.

Example 3 2-ethylhexyl acrylate 60s Ethyl acrylate 68 parts Maleic anhydride
2 benzoyl peroxide
0.5 part ethyl acetate
130 parts of each of the above compounds were charged into a reaction vessel, kept at 75 to 80°C for 10 hours while stirring in a nitrogen stream, and then 20 parts of toluene was added to complete the reaction.
The nonvolatile content of the copolymer solution thus obtained was 39.9
% and the viscosity was 4,300 cps16-.

Next, to 100 parts of the solid content of this bath liquid, [10 parts of Bleiofen BA-5054J, 1 nicanol H=
8. 10 parts of DJ (xylene resin manufactured by Mitsubishi Gas Chemical Co., Ltd.), [
Finton 1500J (Nippon Zeon oil pulp) 10
and [Super Beckamine J-820-60J 1
A pressure sensitive adhesive composition was obtained.

Table 1 shows the adhesives evaluated in the same manner as in Example 1, except that this composition was used.

Comparative Example 1 A comparative composition was obtained by repeating the same procedure as in Example 1, except that no phenolic resin was used. Regarding this as well, the performance was evaluated in the same manner as in Example 1.

The results are shown in Table 1.

14- Comparative Example 2 A comparative composition was obtained by repeating the same procedure as in Example 2, except that no xylene resin was used. Regarding this as well, the performance was evaluated in the same manner as in Example 1.

The results are shown in Table 1.

Comparative Example 6 A comparative composition was obtained by repeating the same operation as in Example 6, except that no phenol tsukuza was used. Regarding this, the performance was evaluated in the same manner as in Example 1.
I did this.

The results are shown in Table 1.

To measure the adhesion strength, each 25 mm wide test piece was taken out from the storage atmosphere and placed in a room at 20°C and 65% R (24 mm wide).
After leaving it for a while, the aluminum foil was peeled off in a 180 degree direction. The peeling speed at this time is 60/
It was a minute.

15-

Claims (1)

[Scope of Claims] As an essential component, (acrylic acid alkyl ester having an alkyl group of C2 to CI8 in an amount of N60 to 991%, 1 to 10m-1%)
α,β-ethylenically unsaturated carboxylic acid, and O~6
A copolymer obtained by reacting a polyvinyl compound with a qH amount of %; , or (F metal chelate compound, and if necessary, (G) tackifier resin, based on 1001 parts by weight of the above copolymer, 3 to 30 parts by weight of the above resin B), and the above resin C. ) and 0.5 to 501 parts of component D), (E) or (F).
01 to 10, and the above Jugetsu G) to 5 to 301
A pressure sensitive adhesive composition comprising: