JP2999610B2 - Curing progress type adhesive member - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a curing-adhesion type adhesive which is suitable for bonding various articles such as building materials and home appliances, in which curing proceeds after adhering to an adherend and cohesive strength is improved. Regarding members.

[0002]

2. Description of the Related Art In the field of building materials and home appliances, the adhesive method using an adhesive member such as an adhesive sheet or an adhesive tape has begun to spread, paying attention to advantages such as simplicity. It is strongly required to achieve both good press bonding and strong fixing force such as non-creep after bonding.

Hitherto, a moisture-absorbing-curable pressure-sensitive adhesive has been known to meet the above demand (Japanese Patent Publication No. 60-1746).
No. 7). In this method, the elastic modulus is initially kept low to increase the wettability to the adherend, and is cured by absorbing moisture to improve the cohesive strength over time. However, since the curing proceeds before and after the bonding process, it is necessary to suppress the progress of the curing before the bonding process, and special attention must be paid to its storage and the workability of the bonding process. Atsuta.

On the other hand, there has been known an adhesive member in which adhesive layers having different shear creep compliances are superposed (Japanese Patent Application Laid-Open No. 54-139946). this is,
The adhesive layer has a low elastic modulus and a good pressure-bonding property, and a pressure-sensitive adhesive layer with a high elastic modulus and excellent cohesion. However, since a pressure-sensitive adhesive layer having a good elasticity and a low elastic modulus exists even after bonding, there is a problem that this layer lowers the creep resistance as a whole.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide both good press-fitting property at the time of bonding operation and strong fixing force such as non-creep property after bonding, and also to handle preservability and bonding workability. It is an object of the present invention to develop an adhesive member having excellent properties.

[0006]

According to the present invention, there is provided a curing progress type pressure-sensitive adhesive layer provided on a non-photopolymerized base layer, wherein the base material layer is a curing progress type pressure-sensitive adhesive. It is an object of the present invention to provide a curing-adhesive member which contains a drug for promoting the curing of the layer.

[0007]

According to the above configuration, it is possible to control the curing of the pressure-sensitive adhesive layer to proceed after the bonding treatment based on the chemicals contained in the base material layer. As a result, good bonding properties are maintained for a long time and stably before bonding, and excellent in handling such as preservability and bonding workability. After bonding, curing progresses, cohesive strength is improved, and It can exhibit strong fixing force such as creep property.

[0008]

FIG. 1 shows an example of a curing-adhesive type pressure-sensitive adhesive member according to the present invention. 1 is a base material layer and 2 is an adhesive layer.
One in which the pressure-sensitive adhesive layer 2 is provided only on one side of the base material layer 1,
An embodiment of the present invention includes a structure in which an adhesive layer 2 is provided on one side of the base material layer 1 and an adhesive layer of a type different from the adhesive layer 2 is provided on the other side.

The base material layer 1 is composed of a base polymer and an adhesive layer 2
It is formed as a composition containing a chemical for accelerating the curing. As the base polymer, a polymer that can be formed into a sheet is used. Preferably, acrylic polymer, vinyl chloride polymer, vinyl acetate polymer,
Styrene-based polymers, urethane-based polymers, fluorine-based polymers, copolymers of monomers forming these polymers, blends of the above-mentioned polymers, and the like are used.

Specific examples of the acrylic polymer include homopolymers and copolymers of acrylic acid or methacrylic acid esters, and blends thereof. Examples of the esters of acrylic acid or methacrylic acid include those having an alkyl group such as a methyl group, an ethyl group, and a butyl group. Acrylic polymers are also used as blends with vinyl chloride polymers and styrene polymers.

Specific examples of the vinyl chloride polymer include:
Examples thereof include soft polyvinyl chloride containing a plasticizer such as dioctyl phthalate and low molecular weight polyester, hard polyvinyl chloride containing no plasticizer, a vinyl chloride / ethylene copolymer, and a vinyl chloride / vinyl acetate copolymer. When a vinyl chloride-based polymer is used as a blend, those that can be preferably used include an acrylic polymer, a styrene-based polymer, and a fluorine-based polymer.

Specific examples of the vinyl acetate polymer include:
Examples include polyvinyl acetate, partially saponified polyvinyl alcohol, and vinyl acetate / ethylene copolymer.

Specific examples of the styrenic polymer include:
Styrene derivatives such as (α, ο-) methylstyrene and ο-chlorostyrene and / or styrene homopolymers or copolymers, styrene derivatives and / or copolymers of styrene and acrylic acid esters, and the like. Can be A blend of a styrene-based polymer with a flexibility improver such as butadiene rubber or styrene-butadiene rubber can also be preferably used.

Specific examples of the urethane-based polymer include those comprising an aliphatic or aromatic diol and a polyfunctional isocyanate. Examples of the diol include polyether diols such as polyethylene glycol and polypropylene glycol, polyester diols composed of terephthalic acid and ethylene diol, bisphenol A and hydrogenated products thereof, and low molecular weight diols such as cyclohexane diol and octylene diol. Examples of the polyfunctional isocyanate include diisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate, and hexamethylene diisocyanate, and triisocyanates.

Specific examples of the fluorine-based polymer include a homopolymer or a copolymer containing a fluorine-containing ethylene-based or propylene-based monomer as a component. Examples of the fluorine-containing ethylene-based monomer include monofluoroethylene, difluoroethylene, trifluoroethylene, and tetrafluoroethylene. Examples of the fluorine-containing propylene-based monomer include monofluoropropylene, difluoropropylene, trifluoropropylene, tetrafluoropropylene, pentafluoropropylene, and hexafluoropropylene.

The base layer 1 may be formed, for example, by adding to the base polymer an agent for promoting the curing of the pressure-sensitive adhesive layer 2, such as an auxiliary agent or a catalyst, and if necessary, a tackifier, a filler, and an antioxidant. And an appropriate additive such as a rust inhibitor, and then forming it into a sheet by any method such as an extrusion method or a casting method. At this time, an agent having poor compatibility with the base polymer and promoting the curing of the pressure-sensitive adhesive layer 2 may be used in combination with an additive having good compatibility or good dispersibility, such as a plasticizer or a low molecular weight polymer. Is preferable from the viewpoint of controlling promotion of curing of the pressure-sensitive adhesive layer 2. The thickness of the substrate layer is appropriately determined according to the purpose of use, but is generally from 10 to 500 μm. Therefore the substrate layer
Is shaped as non-photopolymerized using a base polymer.
Is done.

The agent for accelerating the curing of the pressure-sensitive adhesive layer 2 contained in the base material layer is determined according to the type of the pressure-sensitive adhesive. The content thereof is appropriately determined according to the curability of the pressure-sensitive adhesive layer 2 and the curing acceleration thereof, but is generally 5 to 100 parts by weight per 100 parts by weight of the base polymer.

The curing progress type pressure-sensitive adhesive layer provided on at least one surface of the base material layer includes a moisture curing type, a thermosetting type, and an ultraviolet curing type. The kind of the pressure-sensitive adhesive is not particularly limited, and generally, an acrylic pressure-sensitive adhesive, a silicone-based pressure-sensitive adhesive, a rubber-based pressure-sensitive adhesive, or the like is used.

Specific examples of the acrylic pressure-sensitive adhesive include:
Examples thereof include those based on a homopolymer or copolymer based on an acrylic acid or methacrylic acid ester having a 2-ethylhexyl group or an n-butyl group. Examples of the copolymer component include lower alkyl esters of acrylic acid or methacrylic acid, and esters containing functional groups such as vinyl acetate, acrylic acid, and hydroxyethyl or glycidyl esters of acrylic acid or methacrylic acid.

Specific examples of the silicone-based pressure-sensitive adhesive include those containing polydimethylsiloxane as a main component and a silicone-based polymer mainly composed of low-molecular-weight dialkylsiloxane. Examples of the low-molecular-weight dialkylsiloxane include dimethylsiloxane and diethylsiloxane. .

Specific examples of the rubber-based pressure-sensitive adhesive include a rubber-based polymer mixed with a tackifier resin. Examples of the rubber-based polymer include natural rubber, isoprene-based synthetic natural rubber, styrene / butadiene rubber, and butyl rubber. Rosin,
Rosin derivatives, terpene resins, petroleum resins and the like can be mentioned.

The curing progress type pressure-sensitive adhesive layer used in the present invention comprises:
If necessary, appropriate additives such as a filler, a crosslinking agent, a softening agent, an antioxidant, a coloring agent, and a rust inhibitor may be blended. Further, a curing promoting agent to be contained in the base material layer can be blended within a range that does not impair the pressure-bonding property. The thickness of the curing-adhesive pressure-sensitive adhesive layer is appropriately determined according to the purpose of use and the like, but is generally 5 to 200 μm. The attachment of the pressure-sensitive adhesive layer to the base material layer can be performed by an appropriate method such as a method of applying a pressure-sensitive adhesive or a method of transferring the pressure-sensitive adhesive layer formed on the separator to the base material layer. .

The formation of the pressure-sensitive adhesive layer, which is cured by moisture, can be formed by using, for example, a pressure-sensitive adhesive containing a carboxyl group. In this case, the base layer contains an oxide of a metal of Group IIA of the periodic table such as calcium oxide, strontium oxide, barium oxide or a mixture thereof as a curing promoting agent. Further, a material containing no carboxyl group is preferably used for the base material layer.

The formation of the pressure-sensitive adhesive layer, which is cured by heat, can be formed using a known thermosetting pressure-sensitive adhesive containing a functional group such as a carboxyl group, a hydroxyl group or an epoxy group. In that case, for example, a crosslinking agent such as a polyfunctional isocyanate, a metal chelate compound, or a melamine compound is contained in the base material layer.

The formation of the pressure-sensitive adhesive layer which is cured by ultraviolet rays can be formed, for example, by using a known ultraviolet-curable pressure-sensitive adhesive containing an unsaturated bond or containing an epoxy group. In that case, for example, a photoinitiator (photosensitizer) for curing via an unsaturated bond, such as benzoin, benzoin methyl ether, benzoin ethyl ether, dibenzyl, benzyldimethyl ketal, or an allyldiazonium salt An initiator for curing via the epoxy group is contained in the base material layer.

In the above-mentioned moisture-curable pressure-sensitive adhesive layer, curing is promoted by leaving it in a humid atmosphere after pressure-bonding to an adherend, and curing is facilitated outdoors. In the thermosetting pressure-sensitive adhesive layer, curing proceeds by performing a heat treatment such as thermocompression bonding. In the ultraviolet-curable pressure-sensitive adhesive layer, curing proceeds by irradiating the adherend that transmits ultraviolet light with ultraviolet light.

The preferred curing-adhesive member of the present invention comprises
The elastic moduli of the pressure-sensitive adhesive layer 2 and the base material layer 1 before bonding to the adherend are α and β, respectively, and the pressure-sensitive adhesive layer 2 and the base material layer 1 after 5 hours have passed after bonding to the adherend. When the elastic moduli are γ and δ, respectively, curing proceeds after bonding so as to satisfy α <β ≦ δ <γ. The formation of the pressure-sensitive adhesive member exhibiting such curing characteristics can be performed by including an amount of a curing promoting agent in the base material layer according to the curing progress characteristics of the pressure-sensitive adhesive layer.

By satisfying the relationship of α <β ≦ δ <γ, the wettability to the adherend at the time of bonding is excellent, and the cohesive force is increased after a lapse of a predetermined time after the bonding, so that the cohesive strength is increased. It can have excellent adhesive properties such as creep properties. Moreover, since the elastic modulus (β) of the base material layer before bonding is higher than that of the pressure-sensitive adhesive layer (α), it is easy to handle and excellent in bonding workability.

The curing-adhesive type pressure-sensitive adhesive member of the present invention can be preferably used for bonding various adherends that need to be bonded for a long period of time, such as building materials and home appliance articles. Examples of the adherend include wood, metals such as steel, stainless steel, chromium, and nickel, ABS resin, polyethylene, polypropylene, polyvinyl chloride, polycarbonate, polystyrene, noryl resin, polyphenylene sulfide, polyetheretherketone, polyetherimide, and polyacetal. , Polyimide, urea resin, thermoplastic or thermosetting resin such as polyester, SiO ₂ , Al ₂ O ₃ , Zn
Examples include inorganic materials containing components such as O ₂ and MgO.

The adherend may be appropriately surface-treated. That is, for example, wood coated with varnish, rosin, etc., metal coated with alkyd melamine, acrylic urethane, acrylic melamine, epoxy resin, etc., and metal coated with rustproofing such as cationic electrodeposition coating or anion electrodeposition coating. , Wood, metal, resin, ceramic and the like may be surface-treated with a different material.

[0031]

【Example】

Example 1 92 parts (parts by weight, hereinafter the same) of 2-ethylhexyl acrylate, 8 parts of methyl methacrylate, 0.4 part of 2,2'-azobisisobutyronitrile were put into a four-necked flask together with 250 parts of ethyl acetate. 30 parts of calcium oxide (400 mesh pass) per 100 parts of the resulting polymer was added to a polymerization solution obtained by performing a polymerization treatment at 60 ° C. for 8 hours in a nitrogen atmosphere;
30 parts of coumarone indene resin (softening point: 71 ° C.) and 2 parts of trifunctional isocyanate were added to obtain a substrate layer solution, which was applied on a separator made of a 25 μm-thick polyester film treated with a release agent, A drying treatment was performed at 100 ° C. for 5 minutes to obtain a base material layer having a thickness of 100 μm.

On the other hand, 2-ethylhexyl acrylate 9
0 parts, 10 parts of acrylic acid, and 0.4 parts of 2,2′-azobisisobutyronitrile are put together with 250 parts of ethyl acetate into a four-necked flask, and polymerized at 60 ° C. for 8 hours under a nitrogen atmosphere to obtain. To the resulting polymerization solution, 0.8 part of a trifunctional isocyanate was added per 100 parts of the produced polymer to obtain a pressure-sensitive adhesive solution, which was applied to a separator made of a 25 μm-thick polyester film treated with a release agent, and heated at 100 ° C. For 5 minutes to obtain an adhesive layer having a thickness of 50 μm.

Next, after laminating the pressure-sensitive adhesive layer on the base material layer, the separator of the base material layer is peeled off, and the pressure-sensitive adhesive layer is also laminated on the surface thereof. A cured progress type pressure-sensitive adhesive member of the present invention was obtained.

Example 2 95 parts of octyl acrylate, 5 parts of methacrylic acid, 2,2 ′
-0.4 parts of azobisisobutyronitrile was put into a four-necked flask together with 250 parts of ethyl acetate, and the mixture was placed under a nitrogen atmosphere.
30 parts of calcium oxide (400 mesh pass) and 2 parts of trifunctional isocyanate were added to 100 parts of the produced polymer to the polymerization solution obtained by performing the polymerization treatment at 0 ° C. for 8 hours to obtain a pressure-sensitive adhesive solution, and the pressure-sensitive adhesive solution was used. A curing progress type pressure-sensitive adhesive member of the present invention was obtained in the same manner as in Example 1 except that the pressure-sensitive adhesive layer was formed.

Comparative Example An adhesive member was obtained in the same manner as in Example 1 except that a substrate layer solution containing neither calcium oxide nor coumarone-indene resin was obtained, and the substrate layer solution was formed using the substrate layer solution.

Evaluation Test The pressure-sensitive adhesive members obtained in Examples and Comparative Examples were cut to a width of 20 mm, and the following characteristics were examined using the cut pieces.

Elastic Modulus The shear storage elastic modulus (20 ° C.) of the base material layer and the pressure-sensitive adhesive layer was measured at a frequency of 1 Hz with a parallel disk using a dynamic viscoelasticity measuring device (manufactured by Rheometric Far East). did. α and β are the elastic moduli of the pressure-sensitive adhesive layer and the base material layer at the initial stage, respectively, and γ and δ are the elastic moduli of the pressure-sensitive adhesive layer and the base material layer after 5 hours, respectively. In addition, when preserving for 5 hours, the preservation is 30 degreeC, humidity 80% R. H. (Hereinafter the same).

Adhesive Strength Adhesive strength at the initial stage and after 5 hours of adhesion to a stainless steel plate was measured in accordance with JIS Z 1522.

Deviation distance (creep characteristics) Stainless steel plate (30 mm x 120 mm)
An adhesive member (10 mm in width) was adhered to one end in the longitudinal direction of (× 3 mm) with an adhesion area of 20 mm × 10 mm, left for 5 hours, and then heated at 40 ° C. for 20 minutes. Next, a stainless steel plate is vertically arranged such that the adhesive member is at the lower end, a load of 500 g is applied to the edge of the adhesive member, and left at 40 ° C.
The displacement distance from the beginning of the adhesive member after one hour had elapsed was measured by a creep tester.

The results are shown in Table 1.

[Table 1]

[0041]

According to the present invention, during the work of bonding to the adherend, the wettability is excellent, and good pressure-bonding properties are exhibited. It is possible to obtain a pressure-sensitive adhesive member having a strong fixing force such as adhesiveness and excellent in handling properties such as storability and bonding workability.

[Brief description of the drawings]

FIG. 1 is a sectional view of an embodiment.

[Explanation of symbols]

 1: base material layer 2: hardening progress type pressure-sensitive adhesive layer

Claims (2)

(57) [Claims] 1. A curing-adhesive type pressure-sensitive adhesive layer is provided on a substrate layer that is not photopolymerized , and said substrate layer contains an agent for accelerating the curing of the curing-adhesion-type pressure-sensitive adhesive layer. A curing progress type pressure-sensitive adhesive member, characterized in that: 2. The pressure-sensitive adhesive layer according to claim 1, wherein the base material layer contains an oxide of Group IIA metal or a mixture thereof and does not contain a carboxyl group, and the pressure-sensitive adhesive layer contains a carboxyl group.
Curing progress type pressure-sensitive adhesive member according to 4.