JPH0834962A - Tacky agent composition and tacky processed article - Google Patents

Abstract

PURPOSE:To obtain a tacky agent composition having excellent heat resistance, adhesiveness to a curved surface, peel strength under fixed load and adhesiveness to a rough face at low temperature and to prepare a tacky processed article. CONSTITUTION:This tacky agent composition comprises 100 pts.wt. of an acrylic polymer, 10-40 pts.wt. of a tackifier resin and 0.01-2 pts.wt. of a curing agent except an isocyanate-based curing agent. The acrylic polymer is composed of 90-99.5 pts.wt. of a mixture of 60-100wt.% of a 2-18C alkyl group-containing (meth)acrylic alkyl ester monomer and 40-0wt.% of a vinyl-based monomer copolymerizable with the alkyl ester monomer and 10-0.5 pt.wt. of a carboxyl group-containing vinyl-based monomer. The tackifier resin has 125-160 deg.C softening point and 0-30 acid value.

Description

Detailed Description of the Invention

[0001]

The present invention has excellent adhesiveness to curved surfaces and peeling force under constant load, adhesive strength, storage power, ball tack, adhesiveness to rough surface, adhesiveness at low temperature, adhesiveness to olefin and The present invention relates to a pressure-sensitive adhesive composition having an excellent balance of physical properties such as initial tack, and an adhesive processed product obtained by coating the same.

[0002]

2. Description of the Related Art Conventionally, adhesive products such as double-sided tapes, foam tapes, etc., whose surface has been processed with adhesive, adhesive processed products such as adhesive sheets, have been used for applications such as building materials, home appliances, cushioning materials for automobiles, gap tapes, etc. Widely used.

As the pressure-sensitive adhesive composition used for the above-mentioned pressure-sensitive adhesive processed product, a solvent-type pressure-sensitive adhesive composition mainly composed of an acrylic resin is used because it is excellent in weather resistance, durability, heat resistance, cold resistance, water resistance and the like. Has been. In recent years, as the applications of these adhesive processed products have expanded, there has been an increasing demand for adhesives having a better balance between higher heat resistance and other physical properties.

For example, in the case of home electric appliances and the like, it is necessary to stick the above-mentioned adhesive processed product to a curved surface of plastic or the like, and the adhesive force corresponding to this and the elasticity of the adhesive composition itself (hereinafter referred to as "curved surface adhesiveness"). Is required. In addition, depending on the application, a load may occur perpendicularly to the end of the adhesive processed product attached to the plastic molded product, and the adhesiveness and elasticity of the adhesive composition itself (hereinafter "Constant load peel force") is required.

In order to satisfy the balance between the above-mentioned curved surface adhesiveness and the adhesive force such as the constant force peeling force and the stress deformation followability, the adhesive composition should be used with a large amount of polar monomers and high cohesive force monomers. Alternatively, or by increasing the amount of the tackifying resin added or the amount of the curing agent has been devised.

In JP-A-3-281587, by setting the hydroxyl value of the tackifying resin to be contained to 50 to 100, high peeling resistance and low temperature tack are excellent without impairing adhesive properties such as cohesive force. Techniques for acrylic pressure sensitive adhesive compositions are disclosed. However, also by the technique disclosed in the above publication, etc., while having the curved surface adhesiveness and the constant load peeling force, the adhesive force, the storage force, the ball tack, the adhesiveness to the rough surface, the adhesiveness at low temperature, the olefin Up to now, there has been no one satisfying the balance of various physical properties such as tackiness and initial tack.

Particularly, in the case of a double-sided tape which is developed for various uses, it is possible to highly satisfy the low-temperature adhesiveness to an adherend having a rough surface such as the adhesiveness of a plastic foam at a low temperature and other adhesive properties. It is necessary and such a high-performance general-purpose adhesive has not been developed yet.

[0008]

DISCLOSURE OF THE INVENTION In view of the above, the present invention has a pressure-sensitive adhesive composition having excellent heat resistance and excellent curved surface adhesiveness, constant load peeling force, and rough surface adhesiveness at low temperature, and an adhesive processing. The purpose is to provide goods.

[0009]

The gist of the present invention is to provide a pressure-sensitive adhesive composition containing 100 parts by weight of an acrylic polymer, 10 to 40 parts by weight of a tackifying resin, and 0.01 to 2 parts by weight of a curing agent excluding an isocyanate type. A pressure-sensitive adhesive composition comprising
The acrylic polymer has an alkyl group with 2 to 2 carbon atoms.
90 to 99.5 parts by weight of a mixture of 60 to 100% by weight of an alkyl ester monomer of (meth) acrylic acid of 18 and 40 to 0% by weight of a vinyl-based monomer copolymerizable with the alkyl ester monomer, and containing a carboxyl group It is composed of 10 to 0.5 parts by weight of a vinyl-based monomer, and the tackifying resin has a softening point of 125 to 160 ° C. and an acid value of more than 0 to -30.

The acrylic polymer is a mixture of an alkyl ester monomer of (meth) acrylic acid having an alkyl group having 2 to 18 carbon atoms and a vinyl monomer copolymerizable with the alkyl ester monomer, and a carboxyl group. Containing vinyl monomer.

The alkyl ester monomer of (meth) acrylic acid having 2 to 18 carbon atoms in the alkyl group is not particularly limited, and examples thereof include ethyl (meth) acrylate,
Examples thereof include butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and lauryl (meth) acrylate.

The vinyl monomer copolymerizable with the above monomers is not particularly limited, and examples thereof include hydroxyl group-containing monomers such as 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate; (meth) acrylamide, Acrylonitrile, N-vinylpyrrolidone, maleic anhydride and the like; methyl (meth) acrylate, vinyl acetate, styrene, fluorine acrylate, isobornyl (meth) acrylate and the like can be mentioned.

The carboxyl group-containing vinyl monomer is not particularly limited, and examples thereof include carboxylic acids having an ethylenic double bond such as (meth) acrylic acid, itaconic acid and crotonic acid. Further, the vinyl monomer copolymerizable with the alkyl ester monomer and the carboxyl group-containing vinyl monomer may be the same.

The mixture of the alkyl ester monomer of (meth) acrylic acid having 2 to 18 carbon atoms in the alkyl group and the vinyl monomer copolymerizable with the alkyl ester monomer has 2 to 8 carbon atoms in the alkyl group. 18- (meth) acrylic acid alkyl ester monomer 60-
100% by weight, 40 to 0% by weight of a vinyl-based monomer copolymerizable with the alkyl ester monomer. When the alkyl ester monomer of (meth) acrylic acid having 2 to 18 carbon atoms in the alkyl group is less than 60% by weight,
The pressure-sensitive adhesive is hardened and the cohesive force is improved, but the adhesive force and tack are deteriorated, and the adhesive force and the cohesive force cannot be balanced, so the range is limited.

The acrylic polymer is a mixture 90 to 9 of a mixture of an alkyl ester monomer of (meth) acrylic acid having 2 to 18 carbon atoms in the alkyl group and a vinyl monomer copolymerizable with the alkyl ester monomer.
9.5 parts by weight and 10 to 0.5 parts by weight of the carboxyl group-containing vinyl monomer. If the amount of the carboxyl group-containing vinyl monomer exceeds 10 parts by weight, the crosslinking reaction by the curing agent increases and the pressure-sensitive adhesive becomes hard.
Holding power is improved, but adhesion and tack are poor. If the amount is less than 0.5 parts by weight, the cross-linking structure is small, the cohesive force is not improved, and the holding force is not improved, so the content is limited to the above range.

The pressure-sensitive adhesive composition of the present invention comprises a tackifying resin and a curing agent in addition to the above acrylic polymer. The tackifying resin used in the present invention has a softening point of 125 to 160 ° C and an acid value of more than 0 to -30, and a softening point of 60 to 125 ° C and an acid value. Of more than 30 to 80. The tackifying resin used in the present invention may be used alone or in combination of two or more kinds. When two or more kinds are used in combination, the softening point and the acid value of the entire tackifying resin used may satisfy the above ranges.

The above-mentioned acid value means the number of mg of potassium hydroxide required to neutralize the free fatty acid and resin acid contained in 1 g of the sample, which is measured according to JIS K 0070 and calculated by the following formula. It A = (B × f × 5.611) / S A: Acid value B: Amount of N / 10 potassium hydroxide ethyl alcohol solution used (ml) f: Factor of N / 10 potassium hydroxide ethyl alcohol solution S: Sample (G)

The tackifying resin having a softening point of 125 to 160 ° C. and an acid value of more than 0 to -30 includes:
For example, Pencel D-125 (softening point 125 ° C, acid value 1
3, Arakawa Chemical Industry Co., Ltd.), Pencel D-135 (softening point 135 ° C., acid value 13, Arakawa Chemical Industry Co., Ltd.), Pencel D
-160 (softening point 160 ° C., acid value 13, Arakawa Chemical Industry Co., Ltd.) and the like. Such tackifying resins may be used alone or in combination of two or more kinds. When a tackifying resin is used in combination, the tackifying resin having a softening point outside the range of 125 to 160 ° C. (controlling tackifying resin) or the acid value exceeding 0 to the range of -30. It suffices that an external tackifying resin (controlling tackifying resin) is mixed and the softening point and acid value of the entire tackifying resin used satisfy the above ranges.

The tackifying resin having a softening point of 60 to 125 ° C. and an acid value of more than 30 and -80 is as follows:
For example, Haritac AQ-60 (softening point 60 ° C, acid value 6
5, Harima Kasei Co., Ltd., Haritac AQ-110 (softening point 110 ° C., acid value 65-75, Harima Chemicals Co., Ltd.), pentaline 830 (softening point 110 ° C., acid value 75, manufactured by Rika Herculis Co., Ltd.) and the like. To be Such tackifying resins may be used alone or in combination of two or more kinds. When the tackifying resins are used in combination, the tackifying resin having a softening point outside the range of 60 to 125 ° C. (tackifying resin for adjustment) or the acid value of more than 30 to the range of 80 is used. It suffices that an external tackifying resin (controlling tackifying resin) is mixed and the softening point and acid value of the entire tackifying resin used satisfy the above ranges.

Examples of the above-mentioned adjusting tackifying resin include Haritac F-90 (softening point 90 ° C., acid value 145 or more, manufactured by Harima Kasei Co., Ltd.), FTR6125 (softening point 125.
C, acid value 0, Mitsui Petrochemical Co., Ltd.), FTR7125 (softening point 125 ° C., acid value 0, Mitsui Petrochemical Co., Ltd.), FTR6
110 (softening point 110 ° C., acid value 0, manufactured by Mitsui Petrochemical Co., Ltd.), Halister AD-130 (softening point 130 ° C., acid value 45, manufactured by Arakawa Chemical Industry Co., Ltd.), Halister DS-110S.
(Softening point 110 ° C., acid value 20 or less, Arakawa Chemical Industry Co., Ltd.), FMG-21 (softening point 125 ° C., Arakawa Chemical Industry Co., Ltd.), Alcon P-140 (softening point 140 ° C., acid value 0,
Arakawa Chemical Industry Co., Ltd., Tamanoru 803 (softening point 145-
160 ° C., acid value 45 to 60, manufactured by Arakawa Chemical Industries, Ltd.) and the like.

The pressure-sensitive adhesive composition of the present invention contains 10 parts of the tackifying resin based on 100 parts by weight of the acrylic polymer.
-40 parts by weight. When the amount of the tackifying resin is less than 10 parts by weight, the adhesive force to olefins is poor and the suitability for tape materials and adherends is poor. When it is more than 40 parts by weight, the cohesive force is poor and the holding power is poor. Since it is difficult to express, it is limited to the above range.

The above-mentioned curing agent constituting the pressure-sensitive adhesive composition of the present invention is selected from one kind or a combination of two or more kinds such as an aziridine compound, a metal chelate and an amine group-containing epoxy hardening agent.

The above-mentioned curing agent is not particularly limited except isocyanate type, and for example, Tris-2,4,6-
Aziridine compounds such as (1-aziridinyl) -1,3,5-triazine, tris [1- (2-methyl) aziridinyl] phosphine oxide, hexa [1- (2-methyl) -aziridinyl] triphosphatriazine; ethyl Acetoacetate aluminum diisopropylate, aluminum tris (ethylacetoacetate), zirconium tetraacetylacetonate, diisopropoxybis (acetylacetone) titanate, di-n-butoxybis (triethanolamine) titanate, dihydroxybis (lacticaside) titanate , Tetraoctylene glycol titanate, diisopropoxybis (ethyl acetoacetate) titanate and other metal chelates; T
Examples thereof include amine group-containing epoxy curing agents such as EDRAD-X and TEDRAD-C (manufactured by Mitsubishi Gas Chemical Co., Inc.).

The curing agent is the acrylic polymer 1 described above.
It is 0.01 to 2 parts by weight with respect to 00 parts by weight. 0.0
If it is less than 1 part by weight, an optimum crosslinked structure cannot be produced, so the holding force and constant force peeling force are sacrificed, and if it exceeds 2 parts by weight, the crosslinked structure becomes too much and the adhesive strength and tack deteriorate. Is limited to the above range.

If desired, the pressure-sensitive adhesive composition of the present invention may contain a thickener, a thixotropic agent, a bulking agent, a filler, a pigment, a rust preventive and the like.

By applying the above-mentioned pressure-sensitive adhesive composition of the present invention to a tape or a sheet, a pressure-sensitive adhesive product such as a pressure-sensitive adhesive tape, particularly a double-sided tape or a pressure-sensitive adhesive sheet can be produced. The base material of such a tape or sheet is not particularly limited, and for example, various non-woven fabrics such as rayon-based or cellulose-based; various films such as polyethylene and polyester; cellophane, polyethylene, polypropylene, polystyrene, polyester, etc. Examples of various films include foamed polyethylene, urethane foam, various rubber foams such as neoprene, and the like.

[0027]

The pressure-sensitive adhesive composition of the present invention exerts an effect by expressing a wide range of pressure-sensitive adhesive properties by the acrylic polymer and the tackifying resin in the pressure-sensitive adhesive composition forming an appropriate crosslinked structure by the curing agent. Demonstrate. The tackifying resin blended with the acrylic polymer exhibits an action of improving the adhesive force to polyolefin such as polypropylene (PP). This allows stress on various tape materials and adherends. By cross-linking the acrylic polymer and the tackifying resin with the curing agent, the flow of the tackifying resin due to thermal softening can be suppressed, and cohesive force such as holding force can be exhibited. Further, even if the tackifying resin has a low softening point, the holding force can be exhibited, so that the adhesive force to a low-temperature adherend can be satisfied. At the same time, the optimum range of the constant load peeling force is expanded. The pressure-sensitive adhesive composition of the present invention, by limiting the tackifying resin,
By optimizing the cross-linking to the acrylic polymer, a wide range of adhesive physical properties are expressed and the object of the present invention is achieved.

[0028]

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

Examples 1 to 6 and Comparative Examples 1 to 6 In a four-necked flask equipped with a cooling tube, the monomer was charged at the ratio shown in Table 1, and then 81.8 parts by weight of ethyl acetate was charged and the mixture was heated. After warming and refluxing for 30 minutes, 0.1 part by weight of benzol peroxide was added dropwise and reacted for 7 hours. Thereafter, 0.1 part by weight of benzol peroxide was further added dropwise and the reaction was carried out for 3 hours. Then, 40.4 parts by weight of toluene was added thereto and cooled to obtain a transparent and viscous acrylic polymer solution. The acrylic polymer solution and the tackifying resin were mixed in the proportions shown in Table 1 to obtain a mixture. Next, a curing agent was mixed to obtain an adhesive composition. The pressure-sensitive adhesive composition obtained above was applied to a release paper with a doctor blade.
5 μm (DRY) coating was applied. Next, it was dried for 5 minutes in a dryer at 80 ° C. Next, the thickness is 40 μm and the weight is 50 g / m ^2.
A double-sided tape was prepared by sticking an adhesive on both sides of the non-woven fabric with a pressure roller. This double-sided tape is at temperature 20
It was aged for 7 days in a constant temperature and humidity of ℃ and 65% humidity.

Examples 7-12, Comparative Examples 7-12 Examples 1-6, except that the monomer composition of the acrylic polymer and the tackifying resin were changed to the proportions shown in Table 2.
A pressure-sensitive adhesive composition was obtained in the same manner as in Comparative Examples 1 to 6 to prepare a double-sided tape.

In Tables 1 and 2, BA is butyl acrylate, 2EHA is 2-ethylhexyl acrylate,
AAC represents acrylic acid and 2HEMA represents 2-hydroxyethyl methacrylate, respectively. In Table 1, D-
135 is Pencel D-135 (softening point 135 ° C, acid value 13) manufactured by Arakawa Chemical Industry Co., Ltd., and D-160 is Pencel D-160 (softening point 160 ° C, acid value 13) manufactured by Arakawa Chemical Industry Co., Ltd. P-140 is Arakawa Chemical Industry Co., Ltd., Alcon P-140 (softening point 140 ℃, acid value 0), AD-13
0 represents Harrier Star AD-130 (softening point 130 ° C., acid value 45) manufactured by Harima Chemicals, Inc., respectively.

In Table 2, P-830 is pentaline 830 manufactured by Rika Hercules Co., Ltd. (softening point 110 ° C., acid value 75).
AQ-60 is a product of Harima Kasei Co., Ltd., Haritac AQ-
60 (softening point 60 ° C., acid value 65), F-90 manufactured by Harima Chemicals, Haritac F-90 (softening point 90 ° C., acid value 145 or more), DS-110S manufactured by Harima Chemicals,
Harrier Star DS-110S (softening point 110 ° C, acid value 2
0 or less), and FTR6110 represents Mitsui Petrochemical Co., Ltd., FTR6110 (softening point 110 ° C., acid value 0.1 or less), respectively. Further, in Tables 1 and 2, the curing agent represents an aziridine-based HDU (manufactured by Sanko Chemical Industry Co., Ltd.).

Measurement of Physical Properties (1) PP Adhesive Strength A double-sided tape (with a 25 μm PET film backing) was attached to a PP plate, and 90 ° peel strength was measured. (2) Holding power 2 pieces of double-sided tape (with 25 μm PET film backing)
It was stuck on a stainless plate with a size of 5 mm × 25 mm. After this was cured at 80 ° C. for 30 minutes, a load of 1 Kg was applied for 24 hours, and the deviation or dropping time after 24 hours was measured. (3) Peeling force under constant load A double-sided tape (with a 25 μm PET film backing) is pasted on a PP plate with an area of width 25 mm and length 50 mm, 2
The Kg roll was reciprocated once and adhered. After leaving it in a gear oven at 60 ° C. for 30 minutes, a static load of 100 g was applied with the tape surface facing downward (angle is 90 ° with respect to the PP plate). After standing for 3 hours, the distance that the tape peeled from the PP plate was measured.

(4) Adhesiveness on curved surface A double-sided tape having a thickness of 0.05 mm, a width of 15 mm and a length of 15 is used.
It was attached to a 0 mm aluminum plate. 2mm thick,
A PP plate having a width of 250 mm was laminated in the width direction with a pressure roller. After 30 minutes, this PP plate was bent so as to be settled by a jig of 200 mm and a curved surface was formed. A cooling cycle was applied to this 10 times, and the peeling height of the aluminum plate was measured. (5) Low-temperature adhesion In a 5 ° C atmosphere, a double-sided tape (with a 25 μm PET film backing) with a width of 25 mm was applied to a 10-mm-thick urethane foam (previously adhered to a stainless steel plate) and adhered by rolling back and forth once with a roll. did. 2 under the same conditions
After standing for 4 hours, the peeling strength at 180 ° C. was measured with a tensile tester. The pulling speed was 300 mm / min. The test results are shown in Tables 1 and 2.

[0035]

[Table 1]

[0036]

[Table 2]

[0037]

INDUSTRIAL APPLICABILITY The present invention develops an optimum cross-linking structure for a pressure-sensitive adhesive by crosslinking a carboxyl group contained in a tackifying resin and a carboxyl group contained in an acrylic polymer with a curing agent, thereby obtaining a curved surface adhesiveness, It is possible to satisfy the balance between the peeling force under load, the adhesiveness to a difficult-to-be-adhered body such as urethane foam at a low temperature, and other adhesive properties.

Claims (3)

[Claims] 1. A pressure-sensitive adhesive composition comprising 100 parts by weight of an acrylic polymer, 10 to 40 parts by weight of a tackifying resin, and 0.01 to 2 parts by weight of a curing agent excluding an isocyanate type, wherein the acrylic polymer comprises: A mixture of 60 to 100% by weight of an alkyl ester monomer of (meth) acrylic acid having an alkyl group having 2 to 18 carbon atoms and 40 to 0% by weight of a vinyl-based monomer copolymerizable with the alkyl ester monomer 90 to 99.5. The tackifying resin has a softening point of 125 to 160 ° C. and an acid value of more than 0 to 30. A pressure-sensitive adhesive composition comprising: 2. A pressure-sensitive adhesive composition comprising 100 parts by weight of an acrylic polymer, 10 to 40 parts by weight of a tackifying resin, and 0.01 to 2 parts by weight of a curing agent excluding an isocyanate type, wherein the acrylic polymer is A mixture of 60 to 100% by weight of an alkyl ester monomer of (meth) acrylic acid having an alkyl group having 2 to 18 carbon atoms and 40 to 0% by weight of a vinyl-based monomer copolymerizable with the alkyl ester monomer 90 to 99.5. The tackifying resin has a softening point of 60 to 125 ° C. and an acid value of more than 30 to 80. A pressure-sensitive adhesive composition comprising: 3. An adhesive processed product obtained by applying the adhesive composition according to claim 1 or 2.