JPH07305038A - Double-sided adhesive tape for fixing decorative material - Google Patents

Abstract

PURPOSE:To obtain the subject tape not impairing the fanciness inherent in surface decorative material, useful mainly for fitting a surface decorative material on the speaker site of televisions or audio equipment, by providing its surface with a thermally active adhesive layer imparted with deluteredness with surface asperities. CONSTITUTION:This double-sided adhesive tape is obtained by providing one of its surfaces with a thermally active adhesive layer imparted with such delusteredness as to be <=10%. in glossiness through affording asperities 10-50mum in ten-point average roughness and having a dynamic viscosity at 100 deg.C of 2X10<4> to 5X10<5> poise and the other surface with a tack agent layer. It is preferable that a substrate consisting of a nonwoven fabric or plastic film be put in between the thermally active adhesive layer and tack agent layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double-sided adhesive tape which is a decorative material having an opening property and which is mainly used for attaching a decorative material on the surface of a speaker portion of a television, an audio device or the like.

[0002]

2. Description of the Related Art It is necessary to provide an opening at a front surface of a speaker of a television, an audio device or the like as a sound passage so as not to impair the volume and sound quality of the speaker. However, if a large opening is provided, the inside of the speaker can be seen through, which is not desirable in terms of design, and there is also a problem with dust resistance such as dust and dust. The method of obtaining is common. As a specific example, a coarsely knitted knitted fabric using a yarn having a denier of 100 denier or more is used as a blinding material having
One with a mesh woven into 150 mesh or 1m
A common method is to provide a surface decorative material such as a metal plate or plastic sheet that has been punched with mφ or less on the main body in front of the speaker. Double-sided bonding is the method for adhering these surface decorative materials to the main body. Often tape is used.

[0003]

However, in such a surface decorative material, since the surface gloss of the double-sided adhesive tape is generated from the surface of the surface decorative material through the opening of the surface decorative material after the adhesive fixing, the surface decorative material is However, there is a problem that the design of the Therefore, in the double-sided adhesive tape, it is desired that the surface-adhesive-material-bonded side has low gloss.

To solve such a problem, a proposal of a heat-adhesive film containing a heat-expanding material (Japanese Patent Laid-Open No. 4-19829).
There is 0), but in this case, the thickness of the adhesive increases with the expansion of the heat-expandable material and fills the openings, so the openings are completely buried in the thin surface decorative material. Further, there is a problem that the adhesive rises from the opening to the surface, impairing the design. Another problem is that the production efficiency is extremely slow because the heat-expandable material must be dried at a low temperature in order to prevent the heat-expandable material from expanding during drying during film formation. The present invention provides a double-sided adhesive tape, which does not impair the designability by generating gloss after adhesion and fixation like the conventional double-sided adhesive tape and does not impair the designability by filling the openings, and which is excellent in mass productivity. Is.

[0005]

DISCLOSURE OF THE INVENTION The present invention has a matte heat-activatable adhesive layer having a glossiness of 10% or less by providing unevenness on one surface. A double-sided adhesive tape having a pressure-sensitive adhesive layer on the other side, the heat-activatable adhesive having a dynamic viscosity at 100 ° C. of 2 × 10 ⁴ to
It is achieved by a configuration characterized in that it is in the range of 5 × 10 ⁵ poise.

The basic components of the heat-activatable adhesive used in the present invention include urethane resin, polyester resin, styrene-butadiene rubber, natural rubber, acrylic rubber, butyl rubber, nitrile rubber, styrene block copolymer and chloroprene rubber. A polymer material having heat activity can be used. If necessary, an appropriate amount of a compounding agent such as an adhesion-imparting resin, a thickener, a softening agent, an antiaging agent, a filler, a plasticizer, a stabilizer, a pigment, and a crosslinking agent is added to this basic component. be able to. Among them, the pigment makes the hue of the heat activated adhesive the same as that of the surface decorative material to make the heat activated adhesive exposed from the surface decorative material inconspicuous and absorbs a part of visible light so that it has a matte property. Is also effective to obtain.

The heat-activatable adhesive thus blended is dissolved in, for example, a solvent and applied to a stepped paper having irregularities and dried to form a film. When this is peeled off from the process paper, the irregularities on the process paper surface are reversed to the heat-activatable adhesive, so that the heat-activatable adhesive surface can have matte properties. The matteness referred to here can be represented by the glossiness, but in order not to impair the design of the decorative material, the 60-degree specular glossiness measured by the JIS Z-8741 specular glossiness measurement method is 10%. It must be less than or equal to 5, preferably 5
% Or less. The process paper used is not particularly limited as long as the heat-activatable adhesive surface has the above-described matte property. As a method for obtaining a matte surface, there is a method in which a film-formed heat-activatable adhesive is passed between embossing rolls having unevenness to reverse the unevenness, but the method is not limited to the above method.

The unevenness of the surface is the ten-point average roughness (JIS
B-0601) is in the range of 10 μm or more and 50 μm or less, preferably 15 μm or more and 30 μm or less. If the ten-point average roughness is less than 10 μm, the unevenness becomes smooth and gloss occurs due to slight pressure during handling, and if it exceeds 50 μm, the heat-activatable adhesive for the concave portion is the adherend when laminating. There is a problem that it does not come into sufficient contact with the surface cosmetic agent and it is difficult to obtain adhesive strength.

The heat-activatable adhesive having the matte structure as described above has a dynamic viscosity of 2 × 10 ^{4 at} 100 ° C.
˜5 × 10 ⁵ poise, preferably 5 × 10 ^{4 to} 3 × 10 ⁵
Poise needs to be adjusted. If the dynamic viscosity at 100 ° C. is less than 2 × 10 ⁴ poise, the surface of the heat-activatable adhesive will flow at the time of heating and laminating to an adherend, unevenness will disappear and gloss will be generated. Will reduce the design. Further, when the dynamic viscosity at 100 ° C exceeds 5 × 10 ⁵ poise, the unevenness of the surface of the heat-activated adhesive on the contact surface with the decorative material is less likely to be crushed during lamination with the decorative material, and the effective contact area with the decorative material is increased. However, there is a problem in that the adhesive strength becomes smaller and the adhesive strength is less likely to be expressed, and when the pressure is increased forcibly to adhere the adhesive material, the designing property of the decorative material is deteriorated due to the pressure applied. That is, the heat-activatable adhesive is less likely to have gloss on the non-contact surface with the adherend at the time of heating and laminating, and unevenness is crushed on the adherend contact surface to obtain an adhesive area.
The dynamic viscosity at 0 ° C. needs to be adjusted to 2 × 10 ^{4 to} 5 × 10 ⁵ poise, preferably 5 × 10 ^{4 to} 3 × 10 ⁵ poise. What is dynamic viscosity in the above

[Formula 1] Required by.

The pressure-sensitive adhesive layer provided on the surface opposite to the matte surface of the heat-activatable adhesive is composed of acrylic ester copolymer, styrene block copolymer, natural rubber, butyl rubber, etc. An acrylic acid ester copolymer is preferable in terms of reliability of weather resistance and repulsion resistance, but is not particularly limited.

The above-mentioned double-sided adhesive tape is a non-woven fabric made of fibers such as rayon, hemp, polyester, polypropylene, etc., depending on the fixing condition of the surface decorative material, the adhering work condition, and the conditions such as pre-processing of the double-sided adhesive tape. It is preferable to provide a plastic film made of biaxially oriented polypropylene, polyester or the like as a support between the heat-activatable adhesive and the pressure-sensitive adhesive, and to further enhance the reliability of adhesion, the support previously coated with a primer is used. A body may be provided.

Further, the double-sided separator provided in contact with the pressure-sensitive adhesive has unevenness on the surface in contact with the heat-activatable adhesive layer, that is, the surface opposite to the contacting surface with the pressure-sensitive adhesive in the wound state. 10-point average roughness of 10 μm or more 50
Since it is not more than μm, preferably not less than 15 μm and not more than 30 μm, it is preferable that the matte property of the contact surface of the heat-activatable adhesive is not impaired and stable matte property is obtained in the wound state.

[0013]

The double-sided adhesive tape does not generate gloss when the double-sided adhesive tape is used to bond and fix a surface decorative material having openness, and the double-sided adhesive tape does not reflect from the openings of the surface decorative material to generate gloss. In addition, the double-sided adhesive tape does not fill the opening and is not exposed on the surface, and the original design of the surface decorative material can be maintained.

[0014]

EXAMPLES Examples of the present invention will be shown below. The term "parts" in the formulation means parts by weight. (Example 1) A heat-activatable adhesive of the following formulation (1) containing chloroprene rubber as a main component dissolved in a solvent was applied to a release-processed process paper so that the thickness after drying was 70 μm, After drying at 90 ° C. for 3 minutes, 100% rayon nonwoven fabric with a basis weight of 14 g / m ² was used as a support on the surface of the heat activated adhesive.
Heat laminated at ℃. Further, on this support surface, an adhesive BPS53 containing an acrylic acid ester polymer as a main component
11 (manufactured by Toyo Ink Co., Ltd.) was applied on the separator described below so that the thickness after drying was 70 μm, dried, and then laminated.

Compounding (1) Chloroprene rubber 100 parts (Chlorobrene A90 manufactured by Denki Kagaku Kogyo Co., Ltd.) Kumaron indene resin 35 parts (Esclon V120 manufactured by Nippon Steel Chemical Co., Ltd.) C ₉ petroleum resin 15 parts Carbon powder 2 copies

Further, the heat-activatable adhesive surface of the above laminate obtained by peeling off the process paper is brought into contact with an embossing roll which has been subjected to unevenness processing and releasing treatment, and the unevenness is transferred to the surface of the heat-activatable adhesive agent to have a matte property. A double-sided adhesive tape was obtained. The separator was made of high-quality paper having a basis weight of 80 g / m ² as a base material, and a polypropylene layer having a thickness of 30 μm was provided on both surfaces, and unevenness was formed on one surface by passing between the embossing rolls. Further, a silicone mold release agent was applied to both surfaces and dried to give mold releasability. The adhesive was applied to the non-concave surface of the separator.

(Example 2) The following formulation (2) was applied to the concavo-convex surface of the separator of Example 1 to give a coating thickness of 70μ after drying.
m, a double-sided adhesive tape having a matting property, which is laminated on the laminated product of the separator, the adhesive and the support of Example 1 and further peeled off the separator coated with the heat-activatable adhesive. Got

Formulation (2) Styrene block copolymer 100 parts (Califlex TR1107 Shell Chemical Co., Ltd. styrene / isoprene weight ratio = 13/87) Rosin ester resin 40 parts (Super Ester A125 manufactured by Arakawa Chemical Co., Ltd.) ) Carbon powder 2 parts

(Comparative Example 1) 50 parts by weight of butyl acrylate, 47 parts by weight of 2 ethylhexyl acrylate, 3 parts by weight of acrylic acid, 0.2 of 2 hydroxyethyl acrylate
Monomer consisting of parts by weight of toluene / ethyl acetate = 50/50
50% of a solution of the polymerization initiator t-butyl peroxybenzoate in a nitrogen atmosphere at a temperature of 80 ° C. under stirring in a nitrogen atmosphere.
g was added dropwise over 1 hour, the polymerization reaction was continued for 7 hours, and then 0.2 part of hydroquinone as a polymerization inhibitor was added to obtain a polymer. The weight average molecular weight of this polymer was 430,000 as measured by gel permeation chromatography. Solid 1 of this polymer
To 00 parts by weight, 25 parts by weight of rosin-based resin Pencel CS (manufactured by Arakawa Chemical Co., Ltd.) as an adhesion-imparting agent and 2 parts by weight of isocyanate compound Coronate L55ET (manufactured by Nippon Polyurethane Industry Co., Ltd.) as a crosslinking agent were added. Was used in place of the heat-activatable adhesive composition (1) of Example 1, and a double-sided adhesive tape having the same specifications as in Example 1 except for the above was obtained.

100 for the above examples and comparative examples
The dynamic viscosity at 0 ° C, the adhesive strength at 20 ° C, the glossiness, and the designability after lamination were measured. The measuring method is as described below. The measurement results are shown in Table 1.

(Dynamic viscosity) Using a viscoelasticity measuring device,
The shear loss elastic modulus [Pa] at a frequency of 1 Hz was measured, and the dynamic viscosity [poise] was determined by the above equation (1).

(Adhesive Strength) The matte surface of each double-sided adhesive tape is made of warp 1 using 120 denier polyester fiber.
3 kg / c for 2 seconds at 100 ° C for a surface decorative material with a porosity of 40%, which is woven and dyed with a number of wefts of 00 threads / inch and 50 wefts / inch, and impregnated with melamine resin.
A test piece was obtained by heat pressing with a pressure of m ² and laminating. After pressing the test piece, a 25 μm-thick polyester film was attached to the pressure-sensitive adhesive surface, left for 24 hours in an atmosphere of 20 ° C., and the peeling adhesive strength was measured at a peeling speed of 300 mm / min.

(Glossiness) Each double-sided adhesive tape was applied to a 3-inch paper tube at a linear pressure of 1 kg / cm while using a nip roll,
The test piece was wound up so as not to form a nest, left in a roll state at room temperature for 24 hours, and placed in a constant temperature bath at 100 ° C for 20 seconds, and used as a test piece, and the matte surface has a 60-degree specular gloss of JIS Z- It was measured by the method specified in 8741.

(10-point average roughness) 10-point average roughness (JISB-060) on the surface of the heat-activatable adhesive of each double-sided adhesive tape.
1) was measured using a non-contact type surface roughness measuring machine.

[0025]

EFFECTS OF THE INVENTION When a double-sided adhesive tape of the present invention is used to bond a surface decorative material having openness, the double-sided adhesive tape appears to be reflected from the openings of the surface decorative material, or the double-sided adhesive tape is It does not impair the original design of the surface decorative material by filling the openings and exposing it to the surface, and a good appearance can be obtained even when used for bonding the surface decorative material of the speaker part of TV and audio equipment. The effect is that you can do it.

[0026]

[Brief description of drawings]

FIG. 1 shows a sectional view of the double-sided adhesive tape.

FIG. 2 shows a cross-sectional view of measuring the adhesive force.

[Explanation of symbols]

 1, heat activated adhesive layer 2, adhesive layer 3, separator (matte on one side) 4, surface decorative material (entangled weave) 5, double-sided adhesive tape (without separator) 6, polyester film (25μ) 7, support layer

Claims (4)

[Claims] 1. A heat-activatable adhesive layer having a matte property, the glossiness of which is 10% or less by providing unevenness on one surface, and a pressure-sensitive adhesive layer is provided on the other surface of the heat-activatable adhesive layer. A double-sided adhesive tape comprising: 100 of the heat-activatable adhesive
A double-sided adhesive tape having a dynamic viscosity at 2 ° C. of 2 × 10 ^{4 to} 5 × 10 ⁵ poises. 2. The double-sided adhesive tape according to claim 1, wherein the surface roughness of the heat-activatable adhesive layer has a ten-point average roughness of 10 μm or more and 50 μm or less. 3. The double-sided adhesive tape according to claim 1, wherein a support layer made of a non-woven fabric or a plastic film is provided between the heat-activatable adhesive layer and the pressure-sensitive adhesive layer. 4. The double-sided adhesive tape according to claim 1, wherein a double-sided release-treated separator is provided on the pressure-sensitive adhesive layer side, and the ten-point average roughness of the surface of the separator not contacting the pressure-sensitive adhesive is 10 μm or more and 50 μm or less. Double-sided adhesive tape characterized by being in the range.