JP2001279199A - Double-sided pressure sensitive adhesive tape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prepare a double-sided pressure sensitive adhesive tape that can exhibit excellent adhesion properties and excellent adhesive force to a structural member such as a floor plate or a decorative plate having a surface layer comprising a polyolefin resin. SOLUTION: This double-sided pressure sensitive adhesive tape is produced by forming, on at least one side of a support, a pressure sensitive adhesive layer which comprises as main components an acrylic copolymer obtained by copolymerizing 5-90 pts.wt. isoalkyl acrylate having a 9-18C isoalkyl group and 5-50 pts.wt. olefin polymer having a polymerizable unsaturated double bond at its end per 100 pts.wt. alkyl acrylate having a 2-8C alkyl group, and is used for securing a structural member having a surface layer comprising 50-100 wt.% polyolefin resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a double-sided pressure-sensitive adhesive tape (including a double-sided pressure-sensitive adhesive sheet) suitable for fixing structures such as floorboards and decorative boards.

[0002]

2. Description of the Related Art Conventionally, fixing methods such as adhesives and nails have been employed for fixing structures such as floorboards and decorative boards, but in recent years, double-sided adhesive tapes have been used in order to shorten the construction period and take measures against organic solvents. Has been actively adopted. However, floor boards and decorative boards, particularly wooden floor boards and decorative boards, have a problem in that the adhesive force is weaker with double-sided adhesive tapes than adhesives because dimensional changes due to moisture absorption and drying are severe.

On the other hand, floorboards and decorative boards made of synthetic resin have appeared as floorboards and decorative boards with little dimensional change, and this is also effective in respect of preserving wood resources. Examples of the synthetic resin include polyolefin resins such as polyethylene resin and polypropylene resin, polyvinyl chloride resin, polyester resin, polyurethane resin, epoxy resin, acrylic resin, polycarbonate resin, ABS
Various synthetic resins such as resin-based resins have been used, and among them, polyolefin-based resins having the advantages of being environmentally friendly and being easy to dispose of are becoming mainstream.

However, polyolefin resins have only a very low polarity since they are composed of only carbon and hydrogen. For example, there is a problem that sufficient adhesive strength cannot be obtained with a highly polar acrylic pressure-sensitive adhesive.

In order to compensate for this, it is necessary to laminate a material other than polyolefin resin on the surface of the floorboard or decorative board as an adherend, which leads to an increase in the cost of the floorboard or decorative board or the like. There is a point.

As an adhesive which easily adheres to a polyolefin resin, for example, in Japanese Patent Application Laid-Open No. 11-140406, "a 100 parts by weight of an alkyl (meth) acrylate having an alkyl group having 4 to 8 carbon atoms is used. It contains an acrylic copolymer in which 17 to 67 parts by weight of an alkyl (meth) acrylate having an alkyl group having 12 to 14 carbon atoms is copolymerized, and has a compressive strength of 5% at 25% compression.
Pressure-sensitive adhesive at a temperature of 0.2 to 5 kg / cm ² ”is disclosed.

[0007] However, the above-mentioned pressure-sensitive adhesive is a material in which the adhesion to a polyolefin-based resin is enhanced by copolymerizing an alkyl (meth) acrylate having a long side chain to make the pressure-sensitive adhesive flexible. Adhesive strength is insufficient for fixing a structure such as a plate, and the above problem cannot be solved.

[0008]

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide excellent adhesion and excellent adhesive strength to structures such as floorboards and decorative boards whose surface layer is made of polyolefin resin. The object of the present invention is to provide a double-sided pressure-sensitive adhesive tape which can exhibit the following.

[0009]

The double-sided pressure-sensitive adhesive tape according to claim 1, wherein at least one surface of the support has 2 to 2 carbon atoms.
Acrylic acid alkyl ester having 8 alkyl groups 1
5 to 90 parts by weight of an isoalkyl acrylate having an isoalkyl group having 9 to 18 carbon atoms and 5 to 50 parts by weight of an olefin polymer having a polymerizable unsaturated double bond with respect to 00 parts by weight. It is characterized in that an adhesive layer containing an acrylic copolymer obtained by copolymerization as a main component is provided.

The double-sided pressure-sensitive adhesive tape according to claim 2 is used for fixing a structure having a surface layer containing 50 to 100% by weight of a polyolefin resin in the double-sided pressure-sensitive adhesive tape according to claim 1. It is characterized by being used.

The pressure-sensitive adhesive used in the pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive tape of the present invention is an alkyl acrylate having an alkyl group having 2 to 8 carbon atoms (hereinafter simply referred to as “alkyl acrylate”) 100 5 to 90 parts by weight of an isoalkyl acrylate having an isoalkyl group having 9 to 18 carbon atoms (hereinafter simply referred to as "isoalkyl acrylate") and 5 Olefin polymer having a heavy bond (hereinafter simply referred to as “olefin polymer”) 5
An acrylic pressure-sensitive adhesive mainly containing an acrylic copolymer obtained by copolymerizing 50 to 50 parts by weight.

The alkyl acrylate used to obtain the acrylic copolymer includes, for example, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, butyl acrylate, sec-butyl acrylate, and t-acrylate. -Butyl, cyclohexyl acrylate, n-octyl acrylate, isooctyl acrylate, 2-ethylhexyl acrylate, and the like. These alkyl acrylates may be used alone or in combination of two or more.

The isoalkyl acrylate used to obtain the acrylic copolymer includes, for example, isononyl acrylate, isomyristyl acrylate, and isostearyl acrylate. These isoalkyl acrylates may be used alone or in combination of two or more.

Further, the olefin polymer used to obtain the acrylic copolymer has an unsaturated double bond copolymerizable with another polymerizable monomer at the terminal and an olefin skeleton in the main chain. Any polymer may be used, and is not particularly limited.

Specific examples of the above-mentioned olefin polymer include, for example, ethylene-butylene copolymer and ethylene-butylene copolymer.
Propylene copolymers, propylene copolymers, ethylene copolymers, butylene copolymers and the like can be mentioned. Commercially available products of the ethylene-butylene copolymer include, for example, a product name “HPVM L” manufactured by Clayton Polymer Japan.
-1251 "and" HPVM L-1253 ", trade name" Terminal functional group type PP "manufactured by Tonen Chemical Co., Ltd., and the like. These olefin polymers may be used alone or in combination of two or more.

The acrylic copolymer, which is the main component of the acrylic pressure-sensitive adhesive used in the present invention, comprises 5 to 90 parts by weight of the isoalkyl acrylate and 100 to 100 parts by weight of the alkyl acrylate and the olefin. It is necessary that 5 to 50 parts by weight of the copolymer is copolymerized.
0 parts by weight of isoalkyl acrylate 1
It is an acrylic copolymer obtained by copolymerizing 0 to 80 parts by weight and 10 to 40 parts by weight of an olefin polymer.

When the copolymerization amount of the isoalkyl acrylate to 100 parts by weight of the alkyl acrylate is less than 5 parts by weight or more than 90 parts by weight, the tackiness of the acrylic pressure-sensitive adhesive becomes insufficient. Therefore, the adhesion of the double-sided pressure-sensitive adhesive tape to the adherend becomes insufficient.

Also, alkyl acrylate 100
When the copolymerization amount of the olefin-based polymer is less than 5 parts by weight, the adhesion of the double-sided pressure-sensitive adhesive tape to an adherend (particularly, an adherend made of a polyolefin resin) becomes insufficient. If the copolymerization amount of the olefin polymer exceeds 50 parts by weight with respect to 100 parts by weight of the alkyl ester, it will not be compatible with the alkyl acrylate or the isoalkyl acrylate.

The above-mentioned acrylic copolymer is a polar polymer having an unsaturated double bond in order to adjust the polarity and the glass transition temperature (Tg), if necessary, within a range not to impair the achievement of the object of the present invention. The monomer may be further copolymerized.

The polar polymerizable monomers include, for example, styrene monomers such as styrene, α-methylstyrene, o-methylstyrene and p-methylstyrene; carboxylic acid vinyl esters such as vinyl acetate; acrylic acid, methacrylic acid Carboxylic acids having a vinyl group such as maleic acid, phthalic acid, and itaconic acid and anhydrides thereof; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl acrylate, and caprolactone-modified ( Examples thereof include vinyl monomers having a hydroxyl group such as (meth) acrylate, polyoxyethylene (meth) acrylate, and polyoxypropylene (meth) acrylate. These polar polymerizable monomers may be used alone or in combination of two or more. Here, “(meth) acrylate” means “acrylate” or “methacrylate”.

The copolymerization amount of the polar polymerizable monomer in the acrylic copolymer is not particularly limited, but the total amount of the above-mentioned alkyl acrylate, isoalkyl acrylate and olefin polymer Is preferably 20% by weight or less.

The copolymerization amount of the polar polymerizable monomer in the acrylic copolymer is an alkyl acrylate,
When the amount exceeds 20% by weight of the total amount of the isoalkyl acrylate and the olefin polymer, the flexibility of the acrylic pressure-sensitive adhesive decreases, and the adhesion of the double-sided pressure-sensitive adhesive tape to the adherend becomes insufficient. is there.

The acrylic copolymer may be crosslinked as needed to improve heat resistance and creep resistance as long as the object of the present invention is not hindered.

The crosslinking method is not particularly limited, but may be, for example, a solution polymerization method in which an acrylic copolymer is polymerized using an organic solvent as a solvent or an emulsion polymerization method in which water is used as a solvent in an emulsion polymerization method. In this case, a polymerizable monomer having a reactive polar group (crosslinkable monomer) is contained as a copolymer component, and a crosslinker having a functional group capable of reacting with the polar group is added, whereby the acrylic copolymer is obtained. Is crosslinked.

Examples of the crosslinking agent include isocyanate crosslinking agents such as tolylene diisocyanate, naphthylene-1,5-diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, xylene diisocyanate, and trimethylolpropane-modified tolylene diisocyanate. Epoxy crosslinking agents such as ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether; N, N'-hexamethylene-1,6-bis (1-aziridinecarboxamide); Aziridine-based crosslinking agents and the like can be mentioned. These crosslinking agents may be used alone or in combination of two or more.

When an acrylic copolymer is polymerized by a bulk polymerization method such as a photopolymerization method, a polyfunctional (meth) acrylate compound is added as a cross-linking agent to thereby polymerize the acrylic copolymer. And crosslinking can be performed simultaneously.

Examples of the polyfunctional (meth) acrylate compound include 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, and 1,9-nonanediol di (meth) acrylate. Acrylate, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, pentaerythritol di (meth) acrylate, glycerin methacrylate acrylate, pentaerythritol tri (meth) ) Acrylate, trimethylolpropane tri (meth) acrylate, allyl (meth) acrylate, divinylbenzene, epoxy (meth) acrylate, polyester (meth) acrylate, urethane (meth) acrylate And the like. These polyfunctional (meth) acrylate compounds may be used alone or in combination of two or more.

The amount of the crosslinking agent to be added is not particularly limited, but may be an acrylic copolymer (in the case of a polymerization method other than the bulk polymerization method) or an acrylic copolymer component before polymerization (in the case of the bulk polymerization method). (Case) The crosslinking agent is preferably 0.01 to 5 parts by weight, more preferably 0.02 to 3 parts by weight, per 100 parts by weight.

If the amount of the crosslinking agent is less than 0.01 part by weight based on 100 parts by weight of the acrylic copolymer or the acrylic copolymer component before polymerization, the cohesive force of the acrylic pressure-sensitive adhesive is not sufficiently improved. However, the heat resistance and creep resistance of the double-sided pressure-sensitive adhesive tape may be insufficient, and conversely, the amount of the crosslinking agent added to the acrylic copolymer or 100 parts by weight of the acrylic copolymer component before polymerization is 5 parts by weight. If it exceeds, the flexibility of the acrylic pressure-sensitive adhesive may be impaired, and the adhesion of the double-sided pressure-sensitive adhesive tape to the adherend may be insufficient.

The method of polymerizing the acrylic copolymer used as a main component of the acrylic pressure-sensitive adhesive is not particularly limited, and examples thereof include a solution polymerization method, an emulsion polymerization method,
Conventionally known various polymerization methods such as a bulk polymerization method such as a photopolymerization method and a pearl polymerization method may be mentioned, and any polymerization method may be employed.

In the case of the solution polymerization method, for example, an organic solvent such as ethyl acetate or toluene is used as a solvent, and for example, azobisisobutyronitrile or benzoyl peroxide is used as a thermal polymerization initiator. In the case of the bulk polymerization method, a photopolymerization method using ultraviolet light (UV) is preferable because a uniform polymer is easily obtained, and a photopolymerization initiator is used in the photopolymerization method.

As the photopolymerization initiator, for example, 4-
Ketone-based photopolymerization initiators such as (2-hydroxyethoxy) phenyl (2-hydroxy-2-propyl) ketone (for example, trade name “Darocure-2959”, manufactured by Merck), methoxyacetophenone, α- Hydroxy-α, α′-dimethyl-acetophenone (for example, trade name “Darocure 1173”, manufactured by Merck),
2,2-dimethoxy-2-phenylacetophenone (for example, trade name “Irgacure 651”, manufactured by Ciba Specialty Chemicals), 2-hydroxy-2-cyclohexylacetophenone (for example, trade name “Irgacure 184”, manufactured by Ciba Specialty Chemicals) ); Ketal-based photopolymerization initiators such as benzyldimethyl ketal; and other photopolymerization initiators such as acylphosphinoxide and acylphosphonate. These photopolymerization initiators may be used alone or in combination of two or more.

The amount of the photopolymerization initiator to be added is not particularly limited.
The amount is preferably 0.01 to 5 parts by weight, more preferably 0.03 to 3 parts by weight, based on parts by weight.

If the addition amount of the photopolymerization initiator is less than 0.01 part by weight based on 100 parts by weight of the acrylic copolymer component before polymerization, the polymerization conversion rate during photopolymerization becomes low and the acrylic When the amount of the photopolymerization initiator exceeds 5 parts by weight based on 100 parts by weight of the acrylic copolymerization component before polymerization, the amount of radicals generated increases, and the amount of the acrylic-based copolymer increases. The molecular weight of the copolymer may be low, and the cohesive force of the pressure-sensitive adhesive layer may be insufficient.

As the lamps used for light irradiation during photopolymerization, those having a light emission distribution at a light wavelength of 420 nm or less are preferable. For example, low pressure mercury lamps, medium pressure mercury lamps,
Examples include a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a chemical lamp, a black light lamp, a microwave-excited mercury lamp, and a metal halide lamp.

Among the above lamps, the chemical lamp efficiently emits light in the active wavelength region of the photopolymerization initiator and has a small amount of light absorption of components other than the photopolymerization initiator. Since it is permeated, it is suitable for obtaining a thick adhesive layer and a double-sided adhesive tape.

The light irradiation intensity of the above-mentioned lamps on the acrylic copolymer component (acrylic photopolymerizable composition) to which the photopolymerization initiator is added is an important factor which determines the degree of polymerization of the obtained acrylic copolymer. It is a factor, it is preferable that it is appropriately set according to the application and the purpose of use of the double-sided pressure-sensitive adhesive tape, for example, when using a cleavage type acetophenone-based photopolymerization initiator as a photopolymerization initiator, generally, The light irradiation intensity in the light wavelength range effective for photodecomposition of the photopolymerization initiator (the light wavelength range usually varies from 365 to 420 nm depending on the type of the photopolymerization initiator) may be 0.1 to 100 mW / cm ^2. preferable.

[0038] To the acrylic pressure-sensitive adhesive used in the present invention, a tackifier may be added, if necessary, in order to improve the adhesion to the adherend and the adhesive force, as long as the achievement of the object of the present invention is not hindered. It may be.

Examples of the tackifier include rosin resins, modified rosin resins, terpene resins, terpene phenol resins, C5 and C9 petroleum resins, cumarone indene resins and hydrogenated products thereof. And the like. These tackifiers may be used alone or in combination of two or more.

The addition amount of the tackifier in the acrylic pressure-sensitive adhesive is not particularly limited, but the tackifier may be added to 100 parts by weight of the acrylic copolymer or the acrylic copolymer component. The amount is preferably 5 to 50 parts by weight, more preferably 10 to 40 parts by weight.

When the amount of the tackifier is less than 5 parts by weight based on 100 parts by weight of the acrylic copolymer or the acrylic copolymer component, the adhesiveness and adhesive strength of the double-sided pressure-sensitive adhesive tape to the adherend are sufficient. The acrylic copolymer or the acrylic copolymer component 10
If the amount of the tackifier is less than 5 parts by weight per 0 parts by weight, the adhesiveness and adhesive strength of the double-sided pressure-sensitive adhesive tape to the adherend may not be sufficiently improved. When the amount of the tackifier added is 5 parts by weight
If the amount exceeds 0 parts by weight, the flexibility of the acrylic pressure-sensitive adhesive may be impaired, and the adhesion of the double-sided pressure-sensitive adhesive tape to an adherend may be insufficient.

In the case where the acrylic copolymer is polymerized from the photopolymerizable composition by a photopolymerization method, when the tackifier is added to the photopolymerizable composition, the polymerization may be inhibited by the polymerization inhibitory action of the tackifier. Since a decrease in the polymerization rate or a decrease in the molecular weight of the acrylic copolymer may occur, in that case, a tackifier having a low polymerization inhibitory property may be selected, or the crosslinking monomer or the chain transfer agent may be used. It is preferable to adjust the amount of addition appropriately. Examples of the tackifier having a low polymerization inhibiting property include a hydrogenated terpene-based resin, a hydrogenated rosin-based resin, a disproportionated rosin-based resin, and an alicyclic saturated hydrocarbon-based resin. These tackifying resins having low polymerization inhibiting properties may be used alone or in combination of two or more.

In the acrylic pressure-sensitive adhesive used in the present invention, an inorganic filler, an organic filler, a softener, a plasticizer, a surfactant, Coupling agent, antioxidant (antiaging agent),
Heat stabilizer, light stabilizer, ultraviolet absorber, defoamer, colorant,
One or more of various additives such as a flame retardant and an antistatic agent may be added.

Examples of the inorganic filler include calcium carbonate, talc, clay, aluminum oxide, silica, and the like. These inorganic fillers may be used alone or in combination of two or more. Is also good. Also, by adding inorganic or organic hollow fine particles having an average particle diameter of 5 to 200 μm as a filler, or by mixing and stirring and dissolving a gas in an acrylic copolymer component before polymerization, acrylic The volume of the system pressure-sensitive adhesive may be increased.

The double-sided pressure-sensitive adhesive tape of the present invention is provided with a pressure-sensitive adhesive layer comprising the above-mentioned acrylic pressure-sensitive adhesive on at least one surface of a support. In addition, the support mentioned here is not only a support generally used as a base material of a normal adhesive tape such as a synthetic resin film (including a synthetic resin sheet) or a nonwoven fabric, but also a normal separator. Release films (including release sheets), release papers, and the like, which are used as the above.

The double-sided pressure-sensitive adhesive tape of the present invention may be a so-called support-type double-sided pressure-sensitive adhesive tape in which pressure-sensitive adhesive layers are provided on both sides of a support (substrate), or a release film or release paper as the support. And a so-called non-support type double-sided pressure-sensitive adhesive tape having a release surface provided with a pressure-sensitive adhesive layer.

As the support (substrate), for example, a synthetic resin film such as a polyethylene terephthalate (PET) film, a synthetic resin foam, a nonwoven fabric, a woven fabric,
Various materials such as paper and metal foil may be used, and these may be used alone or in combination.

In the case of a support type double-sided pressure-sensitive adhesive tape, it is necessary that at least one surface of the support (substrate) is provided with a pressure-sensitive adhesive layer made of the above-mentioned acrylic pressure-sensitive adhesive. The other surface of the support (substrate) may be provided with a pressure-sensitive adhesive layer made of the acrylic pressure-sensitive adhesive, or may be provided with a pressure-sensitive adhesive layer made of a different pressure-sensitive adhesive.

In the case of a non-support type double-sided pressure-sensitive adhesive tape, the pressure-sensitive adhesive layer may be a single pressure-sensitive adhesive layer made of the acrylic pressure-sensitive adhesive or may be different from the pressure-sensitive adhesive layer made of the acrylic pressure-sensitive adhesive. It may be a composite pressure-sensitive adhesive layer in which a pressure-sensitive adhesive layer made of a pressure-sensitive adhesive is laminated. The different pressure-sensitive adhesive used for the composite pressure-sensitive adhesive layer is preferably a pressure-sensitive adhesive that has excellent adhesion to the pressure-sensitive adhesive layer composed of the acrylic pressure-sensitive adhesive and does not cause delamination.

As a method for producing a support type double-sided pressure-sensitive adhesive tape, for example, a roll coating method, a gravure coating method, a casting coating method,
Apply the acrylic pressure-sensitive adhesive or acrylic photopolymerizable composition (in the case of a photopolymerization method) described above by various coating methods such as a calendar coating method and an extrusion coating method, and, if necessary, a drying step.
A pressure-sensitive adhesive layer is formed through a cooling step, a light irradiation step, and the like, and the same operation is carried out to form the pressure-sensitive adhesive comprising the acrylic pressure-sensitive adhesive, the photopolymerizable composition, or a different pressure-sensitive adhesive on the other surface of the support (substrate). The acrylic pressure-sensitive adhesive or the photopolymerizable composition is applied to the release surface of a release film or release paper by the above-described various coating methods, or a drying step if necessary. After passing through a cooling step, a light irradiation step, and the like, the pressure-sensitive adhesive layer is transferred by laminating on one surface of the support (substrate), and the same operation is performed on the other surface of the support (substrate). Examples include a transfer method for transferring an acrylic pressure-sensitive adhesive, a photopolymerizable composition, or a pressure-sensitive adhesive layer formed of a different pressure-sensitive adhesive, and the transfer method is preferable because of excellent productivity.

The non-support type double-sided adhesive tape is
Using a release film or release paper as a support, and forming a single pressure-sensitive adhesive layer composed of the acrylic pressure-sensitive adhesive or acrylic photopolymerizable composition described above on the release surface by the direct coating method described above. Alternatively, it can be obtained by forming a composite pressure-sensitive adhesive layer in which a pressure-sensitive adhesive layer composed of the above-mentioned acrylic pressure-sensitive adhesive or acrylic photopolymerizable composition and a pressure-sensitive adhesive layer composed of a different pressure-sensitive adhesive are laminated.

The thickness of the pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive tape of the present invention is not particularly limited.
It is preferably from m to 1 mm. When the thickness of the pressure-sensitive adhesive layer is less than 20 μm per side, peeling may easily occur due to unevenness or impact on the surface of the adherend. Conversely, when the thickness of the pressure-sensitive adhesive layer exceeds 1 mm per side, adhesion and Even though the adhesion is no longer improved, it can be costly.

The shape of the double-sided pressure-sensitive adhesive tape of the present invention is as follows:
It is not particularly limited, including a normal roll shape,
Any shape such as a sheet shape or an arbitrary shape processed in advance may be used.

The thus obtained double-sided pressure-sensitive adhesive tape of the present invention can exhibit excellent adhesion and adhesion to polyolefin-based resins.
It is particularly preferably used for fixing a structure having a surface layer containing 0% by weight (a surface layer mainly composed of a polyolefin resin), but of course may be used for fixing other adherends. good.

The structure having a surface layer mainly composed of the polyolefin resin is not particularly limited. For example, among the polyolefin resins, 50 to 100% by weight of a high-strength polypropylene resin and wood powder And a floor board or decorative board obtained by molding a polyolefin resin composition containing 50% by weight or less of a synthetic resin other than a fibrous substance or a polyolefin resin.

In fixing a structure having a surface layer mainly composed of the polyolefin resin, the surface of the double-sided pressure-sensitive adhesive tape of the present invention on which the pressure-sensitive adhesive layer made of the acrylic pressure-sensitive adhesive is provided is treated with a polyolefin-based resin. Applies to resin-based surface layers.

[0057]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. In the examples, “parts” means “parts by weight”.

(Example 1)

(1) Preparation of double-sided pressure-sensitive adhesive tape 60 parts of 2-ethylhexyl acrylate, 20 parts of isostearyl acrylate, and an olefin copolymer having a polymerizable unsaturated double bond at a terminal (“HPVML-125”)
3 ", 15 parts of Clayton Polymer Japan Co., Ltd., 5 parts of acrylic acid, 0.1 part of 1,6-hexanediol diacrylate, a photopolymerization initiator (trade name" IRGACURE 65 ")
1), 0.1 part of Ciba Specialty Chemicals) and 20 parts of an alicyclic saturated hydrocarbon resin (trade name "Alcon P-100", Arakawa Chemical Industries) as a tackifier in a separable flask. After uniformly stirring and mixing with, dissolved oxygen was removed by bubbling with nitrogen gas to prepare an acrylic photopolymerizable composition.

Next, a 50 μm thick film subjected to a release treatment
A spacer having a thickness of 0.5 mm is provided on the release-treated surface of the PET film, and the above acrylic photopolymerizable composition is
After casting on the release surface of the ET film, the PET film was bent and coated so that the release treated surface was in contact with the acrylic photopolymerizable composition. In this state, the coating side P
UV irradiation intensity on ET film is 2 mW / cm
Adjust the lamp intensity of the chemical lamp so that it becomes ² .
Irradiation with ultraviolet light was performed for 10 minutes to produce a non-support type double-sided pressure-sensitive adhesive tape.

(2) Evaluation The performance of the double-sided pressure-sensitive adhesive tape obtained above (90-degree angle peeling adhesive strength, shearing adhesive strength) was evaluated by the following method. The results are shown in Table 1.

90 ° angle peeling adhesive strength: Under an atmosphere of 23 ° C., a double-sided adhesive tape sandwiched between PET films is cut into a width of 25 mm × a length of 100 mm.
The film was peeled off to expose the pressure-sensitive adhesive layer, and then adhered to a polypropylene resin plate (width 50 mm × length 150 mm) from the side where the pressure-sensitive adhesive layer was exposed so that the bonding length was 100 mm. Next, the other PET film of the double-sided pressure-sensitive adhesive tape was peeled off, and a thickness of 25
Paste a μm PET film as a backing material,
After a roller having a weight of 2 kg was reciprocated two times from the back side of the backing material and pressed, it was left under the same atmosphere for 24 hours.
Next, in an atmosphere of 23 ° C., the film was peeled in a 90 ° angle direction at a speed of 300 mm / min using a tensile tester,
The 0 degree angle peel adhesion was measured.

Shear adhesive strength: Under an atmosphere of 23 ° C., a double-sided pressure-sensitive adhesive tape was cut into a 25 mm square to obtain a double-sided PE.
After peeling off the T film, two polypropylene resin plates (width 50 mm × length 100 mm, manufactured by Nippon Test Panel Co., Ltd.) are overlapped and adhered at the center to each other so that the polypropylene resin plates are bonded together. After pressure bonding for minutes, it was left under the same atmosphere for 24 hours. Then 23 ° C
Under an atmosphere of 50, using a tensile tester at a speed of 50
It was pulled in the shear direction at a rate of mm / min, and the shear adhesive strength was measured.

The above-mentioned 90-degree angle peeling adhesive strength and shearing adhesive strength were measured using a stainless steel plate (SUS304, manufactured by Nippon Test Panel Co.) and a polypropylene resin plate mixed with 50% by weight of wood flour instead of the polypropylene resin plate. Also went for.

(Example 2) A double-sided pressure-sensitive adhesive tape was prepared in the same manner as in Example 1 except that no tackifier was added in the preparation of the acrylic photopolymerizable composition.

Comparative Example 1 An acrylic photopolymerizable composition was prepared in the same manner as in Example 1 except that an olefin polymer having an unsaturated double bond at a terminal was not added. A double-sided adhesive tape was produced.

Comparative Example 2 The composition of the acrylic photopolymerizable composition was as follows: 80 parts of 2-ethylhexyl acrylate, 20 parts of lauryl acrylate, 2 parts of acrylic acid, 0.02 part of n-dodecanethiol, A double-sided pressure-sensitive adhesive tape was produced in the same manner as in Example 1 except that 0.05 part of 6-hexanediol diacrylate and 0.1 part of a photopolymerization initiator “Irgacure 651” were used.

The performances (90-degree angle peeling adhesive strength, shear adhesive strength) of the double-sided pressure-sensitive adhesive tapes obtained in Example 2, Comparative Example 1 and Comparative Example 2 were measured in the same manner as in Example 1. The results are shown in Table 1.

[0069]

[Table 1]

[0070]

As described above, the double-sided pressure-sensitive adhesive tape of the present invention has 9 to 9 carbon atoms with respect to 100 parts by weight of an alkyl acrylate having an alkyl group having 2 to 8 carbon atoms on at least one surface thereof. An acrylic copolymer obtained by copolymerizing 5 to 90 parts by weight of an acrylic acid isoalkyl ester having an isoalkyl group of 18 and 5 to 50 parts by weight of an olefin polymer having a polymerizable unsaturated double bond at a terminal Since the pressure-sensitive adhesive layer as a main component is provided, it has both excellent adhesion to various adherends and excellent adhesive strength.

In particular, the acrylic copolymer constituting the pressure-sensitive adhesive layer of the double-sided pressure-sensitive adhesive tape of the present invention is copolymerized with a specific amount of an olefin polymer having a polymerizable unsaturated double bond at a terminal. Therefore, it can exhibit excellent adhesion and excellent adhesive strength to an adherend made of a polyolefin resin, and is suitable, for example, for fixing a structure such as a floor panel or a decorative board made of a polyolefin resin. Used for

Claims (2)

[Claims] 1. The method according to claim 1, wherein at least one surface of the support has 2 carbon atoms.
100 parts by weight of an alkyl acrylate having an alkyl group of from 8 to 8 and an isoalkyl ester of an acrylic acid having an isoalkyl group having from 9 to 18 carbon atoms.
A pressure-sensitive adhesive layer containing an acrylic copolymer as a main component obtained by copolymerizing 5 to 50 parts by weight of an olefin polymer having a polymerizable unsaturated double bond at its end and a polymerizable unsaturated double bond is provided. Characteristic double-sided adhesive tape. 2. The double-sided pressure-sensitive adhesive tape according to claim 1, which is used for fixing a structure having a surface layer containing 50 to 100% by weight of a polyolefin resin.