JPS60233181A - Pressure-sensitive adhesive tape or sheet, and releasing agent using therefor - Google Patents

Abstract

PURPOSE:To obtain a pressure-sensitive adhesive tape or sheet having stable unwinding property after storing at a high temperature, by applying a releasing layer containing a copolymer of an ethylenic unsaturated compound, etc. to the back surface of the tape base or sheet base having a pressure-sensitive adhesive layer. CONSTITUTION:The surface of a tape base or a sheet base is coated with a pressure-sensitive adhesive layer optionally using a subbing agent. The objective tape or sheet can be manufactured by applying a releasing agent layer obtained by compounding (A) 100pts.(wt.) of a copolymer of (i) an ethylenic unsaturated compound having carboxyl group (e.g. maleic acid) and (ii) an ethylenic unsaturated compound free from carboxyl group (e.g. vinyl acetate) with (B) 5-45pts. of a long-chain-alkyl ethyleneurea and (C) 0.5-10pts. of a water-soluble polymer (e.g. PVA) to the reverse surface of the above base. EFFECT:Resistant to the migration of the releasing agent to the pressure-sensitive adhesive layer even by winding in the form of a roll. Free from cissing of the paint on the surface of the releasing layer. There is no run of the roll at low- temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to adhesive tapes or sheets based on paper, cloth, plastic films, etc. 1. Adhesive tapes or sheets of the present invention 1. Heat resistance of release agent layer of foils Because there is very little change, the adhesive tape or sheet has stable unwinding properties even when stored at high temperatures, and even when wound into a roll, the release agent is difficult to transfer to the adhesive layer, and the surface of the release agent layer is It has excellent properties such as no paint repellency.

Adhesive tape V or sheet 1~ is wound into a roll and overlaid on the adhesive layer or the back side of the tape or sheet, so that it is temporarily covered and protected by the adhesive layer or the back side of the tape, but when used, the adhesive The tape or sheet is rewound. At this time, it is necessary that the unwinding be carried out smoothly, and furthermore, the release agent must not migrate to the surface of the adhesive layer and cause a decrease in the adhesive strength of the tape or sheath h.

Therefore, conventionally, silicone has been used as a release agent, and long-chain alkyl has been used as a release agent, such as copolymers containing (meth)acrylic acid esters having long-chain alkyl groups, and isocyanes 1 having long-chain argyl groups. The methods used are known. Silicone-based materials are often used in adhesive tapes and sheets because they have strong release properties, but they have very little adhesion between the adhesive layer and release agent layer, so they are not practical for applications that require adhesive properties. Not on point. On the other hand, release agents using compounds with long-chain alkyl groups have slightly higher adhesive properties than silico-5-1 compounds, so the release agent tends to be heavy, and paper, cloth, and nonwoven fabrics are used as base materials. In some cases, there was a problem in that the base material often broke.

As an improvement over the prior art, a technique using long-chain alkylated ethylene urea or N-methylolated higher fatty acid amide together with a reactive polymer as a release agent was proposed in JP-A-52-6385 and JP-A-52-14635. ing. These prior art techniques have provided adhesive tapes or C-I-s that have appropriate unwinding properties even after storage at 50°C for 7 days, and have better self-back adhesive properties than silicone-based tapes. . However, subsequent research has shown that when stored under severe conditions such as high temperature and high humidity, the unwinding force becomes very heavy, and the adhesive strength decreases due to release agent migration to the adhesive layer. It has been found that there are problems with contamination of the adhesive surface, running of the wound roll, and repelling of paint on the surface of the release agent layer.

The present invention solves most of these drawbacks of the prior art. That is, in the present invention, a pressure-sensitive adhesive layer is provided on the surface of a tape base material or a sheet base material via an undercoat if necessary, and <A> carboxyl group is provided on the back surface of the tape base material or sheet base material. <8) 5 to 4 parts by weight of long-chain alkyl ethylene urea, preferably 10 to 30 parts by weight, per 100 parts by weight of the copolymer with an ethylenically unsaturated compound having no carboxyl group. (C) 0.5 to 10 parts by weight of water-soluble polymer, preferably 0
．． (A>component, (B) component and (
A pressure-sensitive adhesive tape or sheet 1 is provided, which is characterized by providing a release agent layer containing component C).

Examples of the ethylenically unsaturated compound having a carboxyl group constituting the copolymer of the component (△) contained in the pressure-sensitive adhesive tape of the present invention or the release agent layer of Sheet 1~ include maleic anhydride, maleic acid, There are acrylic acid, methacrylic acid, itaconic acid, and crotonic acid, and one or more ethylenically unsaturated compounds selected from these groups are used as the Uzuki comonomer of the copolymer of component A>. .

Maleic anhydride, acrylic acid and methacrylic acid are preferred.

In the copolymer of component <A>, examples of the ethylenically unsaturated compound having no carboxyl group include vinyl acetate, an alkyl moiety having 2 to 10 carbon atoms (
meth)acrylate-1~, ethylene and 2~ carbon atoms
There are 10 aliphatic vinyl carboxylates, and one or more ethylenically unsaturated compounds selected from these groups are used as a starting material for the (Δ) component copolymer.

Preferred are vinyl acetate, alkyl acrylates having an alkyl moiety of 2 to 10 carbon atoms, and vinyl aliphatic carbhonates having 2 to 10 carbon atoms.

In the copolymer of component (A), the ethylenically unsaturated compound having a carboxyl group is 1 to 10% by weight, preferably 1 to 5% by weight, and the ethylenically unsaturated compound having no carboxyl group is 99 to 99% by weight. 90% by weight, preferably 99 to 95% by weight, is copolymerized (however, the total of both is 100% by weight). If the amount of the ethylenically unsaturated compound having a carboxyl group is less than 1% by weight, the peelability will deteriorate, while if it exceeds 10% by weight, there will be no particular advantage other than poor water resistance, which is not preferred.

Suitable copolymers of component (A>) include (a) vinyl acetate and an ethylenically unsaturated compound having no carboxyl group, such as an alkyl acrylate having 2 to 110 carbon atoms in an optional alkyl moiety; (b) It is a copolymer of an ethylenically unsaturated compound having a carboxyl group, and in particular, the copolymerization ratio of vinyl acetate and alkyl acrylate having 2 to 10 carbon atoms in the alkyl portion is acetic acid. Vinyl 100-30% by weight, preferably 95-70%
Alkyl acrylate having 2 to 10 carbon atoms in the alkyl moiety - 10 to 70 weight %, preferably 9 to 5 to 30 weight % (however, the total of both if IJ: 1
00Φ amount%) is preferable. If the vinyl acetate content is less than 30% by weight, the releasability will deteriorate, which is not preferable.

Examples of alkyl (meth)acrylates having 2 to 10 carbon atoms in the alkyl moiety include ethyl acrylate, propyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, ethyl methacrylate, propyl methacrylate, and methacrylate. Butyl acrylate, methacrylic brew 2-
Examples include ethylhexyl, but propyl acrylate, butyl acrylate, and 2-ethyl l-bexyl acrylate are preferred.

Examples of the vinyl aliphatic carboxylic acid having 2 to 10 carbon atoms include vinyl propionate, vinyl caffroate, vinyl vursate, etc., with vinyl propionate and vinyl vursate being preferred.

On the other hand, the long-chain alkyl ethylene urea of component (B) has 10 to 30 carbon atoms, preferably 11 to 2 carbon atoms.
There is a compound C, which represents an alkyl group of 6. Particularly preferred is ophthalethylethylene urea.

The long-chain alkyl ethylene urea component (B) is used in an amount of 5 to 45 parts by weight, preferably 10 to 30 parts by weight, per 100 suspended parts of the combined vehicle of the component (Δ).

J Llik, 'Less than 6 parts; False and less (1) is good because the releasability will be lowered, but more than 45 parts by weight will affect the repellency of the paint or bad (or it may be bad because the repellency of the adherend) This is undesirable because it causes contamination.

Examples of the water-soluble polymer of component (C)) include polyvinyl alcohols such as partially saponified polyvinyl alcohol, completely saponified polyvinyl alcohol, and modified polyvinyl alcohol, and natural polysaccharides such as cellulose derivatives such as hydroxyethyl cellulose and yaguacam. These may be used alone or in combination of two or more. Partially saponified polyvinyl alcohol, fully saponified polyvinyl alcohol and modified 1;l polyvinyl alcohol are preferred, degree of polymerization 300
Above, preferably 1000 or more are suitably used.

The water-soluble polymer of component (C) is copolymer 1 of component (a)
0.5 to 10 parts by weight per 00 parts by weight, preferably 0.5
-4 weight parts are used, but if it is less than 0.5 parts by weight, it is not preferable because it will not prevent the paint, especially water-soluble paint, from repelling, while if it is more than 10 parts by weight, it will cause condensation of the stripping agent solution. This is not preferable because the resistance becomes high and the releasability decreases.

To produce the adhesive tapes or sheets 1 to 1 of the present invention, a release agent dispersion containing <A) component, (B) component, and (C) component is applied to one side of the base paper, cloth, or plastic film. This is done by applying and drying.

Release agent dispersion 'a (water-dispersible release agent) is an aqueous emulsion of the copolymer of component (A), long-chain alkyl 1 of component (B)
It can be easily obtained by mixing an aqueous emulsion of dylene urea and an aqueous solution of a water-soluble polymer of component ('C).

The aqueous emulsion of the copolymer of component (Δ) can be produced by emulsion polymerization of appropriate intermediates according to a conventional method. On the other hand, for the aqueous emulsion of f% iJl alkyl ethylene urea, which is the component (B), commercially available products such as Otogaya Chemical (Kiki [Oftex F~1] (approx. 25% aqueous emulsion of ophthalethyl ethylene urea), etc.) are preferably used. Can be used.

The solid content concentration of the water-dispersible stripping agent is 20 to 50% by weight,
Preferably, it is 20 to 40% by weight, and the viscosity WLt100
~30'OOC, Il, Qi'tL< is 200-150
It is 0 cp. "])" is 2-9, preferably 4-B.

The pressure sensitive adhesive tape or sheet of the present invention has a rho=13
- Even after storage for 2 days at 65°C and 80% RH, the adhesive layer maintains good unwinding properties and adhesive strength, and there is no contamination on the surface of the adherend after the adhesive tape or sheet is peeled off. Moreover, it also has excellent performance such that the roll hardly runs at low temperatures and prevents paint from repelling on the surface of the release agent layer. Contamination on the surface of the adherend tends to occur with conventional technology when the adhesive strength of the adhesive layer is improved, and also due to roll running (well, unwinding force decreases too much in winter). This is a drawback of the adhesive tape 1 or sheet of the prior art in that the roll unwinds too much during work, which tends to reduce work efficiency, and the present invention solves these problems.Furthermore, the present invention solves these problems. Repelling of paint on the surface of the layer is a problem when adhesive tape or Sea 1- is used as a masking tape.The present invention solves these problems at the same time.

Thus, the pressure-sensitive adhesive tape or sheet of the present invention is extremely suitable for use in packaging adhesive tapes and masking tapes.

Copolymerization 1 (Δ) Polymerization Method Copolymer (A)-1 Stirrer 4ZJ 21 In a round bottom flask, water 500oC;
, polyvinyl alcohol with a degree of pycnicity of 88 mol% (PVA-217 manufactured by Kuraray > 4.41J) was added, and 7'I (,)
'e-C-+JIl Heat melt. After purging the inside of the flask with nitrogen, raise the temperature inside the flask to 80'C and maintain it at 80°C. 511 parts of each aqueous solution 'A500' were continuously added and emulsified.The resulting emulsion was mixed with aqueous ammonia (1 liter, 185°C) in a milky white emulsion mill at 295°K and solids content of 41.0%. This water-dispersible copolymer (
The viscosity of △) is 6000 cps, and the average particle system is 0.3 μ
Met.

15- Copolymers <A)-2 to 4 Copolymers (Am-2 to 4) having the compositions shown in Table 1 were polymerized in the same manner as Copolymers (A>-1), and their properties are also shown in Table 1.

16- Example 1 Water-dispersible copolymer (A)-1, 100 parts Octadecyl ethylene urine 23.3 parts (Odugaya Kagakusha I!: Octex EM solid content 24.5%) Ammonia (12, 5%) 0.2 parts Pure water 31.4 parts The above back treatment agent formulation has a solid content of 3096 and a viscosity of 370.
CI), 1) H7,2. Apply this mixture to Japanese group 3
0q/m2 was applied, dried for 2 minutes at 130°C, and on the other side was coated with a rubber adhesive consisting of 100 parts of natural rubber, 80 parts of petroleum-based tackifier resin, 2 parts of anti-aging agent, and 0.5 part of flil+yellow. A 30% toluene solution was applied and dried at 150°C for 2 minutes. The sample thus obtained was cut into 20 mm width pieces and wound into a tape shape.

High j! after leaving the tape-shaped sample under various conditions! Unwinding force, adhesion to stainless steel, and running at low temperatures.

Measurements were made to measure regularity and paint repellency. The results are shown in Table 2.

18- Example 2 A copolymer obtained from 1 to 80 parts of 2-ethylhexyl acrylate, 20 parts of vinyl acetate, and 5 parts of acrylic acid was applied to the back side of a Japanese paper base material that had been coated with the back treatment agent of Example 1 and dried. 10
A 30% I.Lune solution of an acrylic adhesive consisting of 0 parts and 5 parts of an adduct of tolylene diisocyanate in trimethylolpropane as a crosslinking agent was applied and dried at 150°C for 3 minutes.

The sample thus obtained was cut into 20 mm width pieces and wound into a tape shape. After placing the tape-shaped samples under various conditions, high-speed unwinding force, self-rear adhesion strength versus stainless steel adhesion, running phenomenon at low temperatures, and repellency due to water-based paint were measured. The results are shown in Table 3.

Examples 3 to 6 A back surface treatment agent was prepared according to the formulation shown in Table 2, and a tape was prepared in the same manner as in Example 1, and various tests were conducted. The results are shown in Table 3.

19- Comparative example-1 Example 1 of JP-A-52-6385 was repeated.

Comparative example-2 Example 2 of JP-A-52-6385 was repeated.

Comparative example-3 Example 1 of JP-A-52-14635 was repeated.

Comparative example-4 Example 2 of JP-A-52-14635 was repeated.

Comparative Example 5 500 g of water and 3 g of polyoxymethylene stearyl ester are placed in a 21 round bottom flask equipped with a stirrer and heated to dissolve at 40°C. After replacing the inside of the flask with nitrogen, the inside of the flask was
Increase temperature to ℃. Vinyl acetate 344 when kept at 80℃
A, a mixture of 40 g of butyl acrylate, 12 g of acrylic acid (I), and 50 g of a 4% ammonium persulfate aqueous solution (+) were continuously added for 5 hours to carry out emulsion polymerization. The resulting emulsion polymer had a solid content of 42. A 1% milky white emulsion was adjusted to pH 5 with aqueous ammonia.The viscosity of this water-dispersible copolymer (A) was 220 cps and the average particle size was 0.
．． 3μ, the Ti7 of the copolymer was at 295°.

The above water-dispersible copolymer 100 parts Octadecyl ethylene urea 23.7 parts (manufactured by Odogaya Chemical Co., Ltd.: Octex EM solid content 24.5%) Ammonia (12.5%) 0.2 parts Pure water 31.4 parts The above formulation has a solids content of 30.0% and a viscosity of 330 cp.

1) It was 87.2. Spread this mixture on Japanese paper for 30 (]/
I11! After applying and drying at 130°C for 2 minutes, the other side was coated with 30% of a rubber adhesive consisting of 100 parts of natural rubber, 80 parts of petroleum-based tackifier resin, 2 parts of anti-aging agent, and 0.5 parts of sulfur.
A toluene solution was applied and dried at 150°C for 2 minutes. The sample thus obtained was cut into a width of 20IIllllI and wound into a tape shape. Various tests were conducted on the tape-shaped sample in the same manner as in Example 1. The results are shown in Table 3.

High-speed rewinding property: Store the tape under the conditions in the table at 120°C.
The unwinding force is measured at 30 m/min.

The tape is stored under the conditions specified in the adhesive chart, and then the 180 peel force is measured at a rate of 3001 lffl/min using a stainless steel plate as the adherend.

The tape was stored under contamination conditions of 5° C. x 80% RH for 2 days, and then attached to a stainless steel plate 5US-430. The attached state was left at 35° C. x 80% RH for XI days, then the adhesive tape was peeled off and the degree of contamination of 5US-430 was examined.

Running (0°C): The tapes obtained in Examples and Reference Examples were
Store at 0°C for 24 hours, then hold the end of the tape and throw it with light force in an atmosphere at 0°C. At that time, we evaluate whether the tape will run or not, depending on whether it stops midway or not.

Repelling with water-based paint: A water-based paint (Nippe Home Paint manufactured by Nippon Paint A) is applied with a spray can to the release agent-treated surface of the tape obtained in Examples and Reference Examples. At this time, the state of repellency of the paint 24- on the surface treated with the release agent is observed.・ Applicant: Nitto Electric Industry Co., Ltd. Idiot 1 person 25-

Claims (1)

[Claims] 1. A pressure-sensitive adhesive layer is provided on the surface of the tape base material or sheet 1 to base material, if necessary, via an undercoat, and (A) is provided on the back surface of the tape base material or sheet base material. (B) 5 to 45 parts by weight of long-chain alkylethylene urea and (C) per 100 parts by weight of a copolymer of an ethylenically unsaturated compound having a carboxyl group and an ethylenically unsaturated compound not having a carboxyl group. At a ratio of 0.5 to 10 parts by weight of water-soluble polymer (△)
A pressure-sensitive adhesive tape or sheet comprising a release agent layer containing components (B) and (C). 2. Adhesive tape or sheet 1-0 according to claim 1, in which an ethylenically unsaturated compound having a nonorboxyl group is copolymerized with the copolymer in an amount of 1 to 10%. If the ethylenically unsaturated compound does not have vinyl acetate, the alkyl moiety has 2 to 10 carbon atoms.
Claims are one or more ethylenically unsaturated compounds selected from the group consisting of alkyl (meth)acrylate-1-, ethylene, and aliphatic vinyl carboxylate having 2 to 10 carbon atoms. The adhesive tape or sheet according to item 1 or 2. 4. The ethylenically unsaturated compound having a carboxyl group is one or more ethylenically unsaturated compounds selected from the group consisting of maleic anhydride, maleic acid, acrylic acid, methacrylic acid, itaconic acid, and crotonic acid. The adhesive tape or sheet 1-05 according to any one of Claims 1 and 3, wherein the water-soluble polymer is polyvinyl alcohol, any of Claims 1 to 4, wherein the water-soluble polymer is polyvinyl alcohol. The adhesive tape or sheet described in . 6. As a solid content, (A) 100 parts by weight of a copolymer of an ethylenically unsaturated compound having a carboxyl group and an ethylenically unsaturated compound not having a carboxyl group (Bl long chain alkyl ethylene urea 5 to 45 parts by weight and <C> water-soluble polymer 0.5 to (O storage part), (A
) component, (B) component, and (C) component. 7. The release agent according to claim 6, wherein 1 to 10% by weight of an ethylenically unsaturated compound having a carboxyl group is copolymerized with the copolymer. 8. The ethylenically unsaturated compound having no carboxyl group is vinyl acetate, and the alkyl moiety has 2 to 10 carbon atoms.
Claim 1, which is one or more ethylenically unsaturated compounds selected from the group consisting of alkyl (meth)acrylate-h, ethylene, and aliphatic vinyl carboxylate having 2 to 10 carbon atoms. 6 or 7. The release agent according to item 6 or 7. 9. The ethylenically unsaturated compound having a carboxyl group is selected from the group consisting of maleic anhydride, maleic acid, acrylic acid, methacrylic acid, itaconic acid, and chloride. The release agent according to any one of claims 6 to 8, which is a sexually unsaturated compound. 10. The release agent according to any one of claims 6 to 9, wherein the water-soluble polymer is polyvinyl alcohol. 11. The release agent according to any one of claims 6 to 9, which is a water-dispersible release agent.