JPH1017827A - Press bonding type, pressure-sensitive adhesive double coated sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a press bonding type, pressure-sensitive adhesive double coated sheet which is excellent in removability for repositioning for application and, when exposed to winding pressure and the like at the time of winding into a roll, is less likely to lose the removability. SOLUTION: This press bonding type, pressure-sensitive adhesive double coated sheet comprises: an acrylic pressure-sensitive adhesive sheet comprising an acrylic polymer prepd. by applying an actinic radiation to a photopolymerizable compsn. composed mainly of an alkyl (meth)acrylate, the acrylic pressure-sensitive adhesive sheet having a compression modulus of elasticity at 25% compression of 0.1 to 50kg/cm<2> ; and a 10 to 100μm-thick non- pressure-sensitive adhesive or slightly pressure-sensitive adhesive masking member laminated on at least one surface of the acrylic pressure-sensitive adhesive sheet so that the surface of the masking member is protruded on the surface of the acrylic pressure-sensitive adhesive sheet and the masking member covers 12 to 50% of the surface of the acrylic pressure-sensitive adhesive sheet.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure-adhesive double-sided pressure-sensitive adhesive sheet, and more particularly, to the pressure-sensitive adhesive force of the front surface of a floor material, a skirting board, a wall material, a ceiling material, etc. The present invention relates to a pressure-adhesive double-sided pressure-sensitive adhesive sheet which can easily adjust the position during the sticking operation because the pressure-sensitive adhesive is hardly exerted and can exhibit sufficient pressure-sensitive adhesive properties by pressure during bonding.

[0002]

2. Description of the Related Art Conventionally, in the field of construction, an adhesive has been widely used for joining building materials. That is,
BACKGROUND ART Adhesives have been widely used for bonding floor materials, skirting boards, wall materials, ceiling materials, and the like to structures at construction sites. However, when joining building materials using an adhesive, a series of operations are performed after preparing the adhesive, applying the adhesive, bonding the building materials together, and waiting for a curing time such as curing of the adhesive. The workability in joining building materials is low, and a relatively long time is required.

Therefore, in recent years, a method of joining a building material such as a skirting board to a structure using a double-sided pressure-sensitive adhesive tape instead of an adhesive has become widespread. In the joining method using a double-sided adhesive tape, by bonding one adhesive layer surface of the double-sided adhesive tape to the building material, the double-sided adhesive tape is fixed to the building material side, and then the other adhesive layer surface of the double-sided adhesive tape is bonded. The building material is joined by sticking it to the sticking position, that is, the surface of the building structure. Alternatively, a method has also been used in which a double-sided adhesive tape is attached in advance to a sticking position where a building material is bonded, and the building material is attached using an adhesive layer outside the double-sided adhesive tape.

[0004] However, in any of the above methods, there is a problem that it is extremely difficult to correct the sticking position after the building material is once stuck to the structure of the building using a double-sided adhesive tape. That is, it is very difficult to re-peel the building material or shift the building material to a correct position after being once attached.

[0005] Therefore, the following two methods have been proposed as methods that can be easily peeled after pasting. The first method is a method in which the release paper of the double-sided pressure-sensitive adhesive tape is subjected to a spine splitting process, and the release paper for temporary fixing and the release paper for final stop are used for sticking. In this method, the release paper for temporary fixing is first peeled off, and the building material is temporarily fixed at the attaching position. Since the adhesive strength of the adhesive layer exposed by peeling the release paper for temporary fixing is not sufficient, if the sticking position is shifted from the target position, remove it again or shift the sticking position Can be. Next, after the position adjustment, the release paper for final fastening is peeled off, and the building material is finally bonded. However, in the method of applying the spinning process to the release paper, the operation is complicated as described above, and it is difficult to adjust the release paper to have sufficient removability. In addition, the release paper has to be split in various forms according to the shape and dimensions of the building material.

A second method is to use a pressure-sensitive adhesive for a double-sided pressure-sensitive adhesive tape, which has a low initial adhesive strength and therefore has removability, and the adhesion of which increases with time.
At the time of re-peeling, it has been difficult to leave an adhesive residue or to give sufficient re-peelability.

[0007] To solve the above problems,
Japanese Patent Application Laid-Open No. 7-310057 discloses an adhesive sheet in which a projection made of a solid non-adhesive substance is formed on at least one surface of an adhesive layer. In this adhesive sheet, fine adjustment of the adhesive sheet can be easily performed at the time of sticking, due to the presence of the convex portion due to the solid non-tacky substance,
In addition, it is described that a non-tacky substance sinks below the surface of the pressure-sensitive adhesive due to a pressing force at the time of bonding, whereby sufficient bonding force can be exhibited.

[0008]

The double-sided pressure-sensitive adhesive tape is usually manufactured in a long form and wound on a roll. That is, the double-sided pressure-sensitive adhesive tape is usually supplied in a state of being wound on a roll.

However, in the adhesive sheet described in Japanese Patent Application Laid-Open No. Hei 7-310057, when the adhesive sheet is wound into a roll, the convex portion made of the non-adhesive substance is pushed toward the adhesive layer side by the winding pressure, and the uniform convex portion is formed. There is a problem that it becomes difficult to maintain the shape. In particular, since a larger winding pressure is applied to a portion close to the core of the roll, in extreme cases, the convex portion sinks and the intended removability may not even be obtained.

An object of the present invention is to provide a pressure-sensitive adhesive double-sided adhesive which is excellent in re-peelability for correcting a sticking position, and is hard to lose re-peelability due to a winding pressure when wound into a roll. To provide a seat.

[0011]

SUMMARY OF THE INVENTION The present invention comprises an acrylic polymer obtained by irradiating a photopolymerizable composition containing an alkyl (meth) acrylate as a main component with actinic rays.
At least one surface of the acrylic pressure-sensitive adhesive sheet having a compression elastic modulus at 5% compression of 0.1 to 50 kg / cm ² has a thickness of 1
A non-adhesive or light-adhesive masking member of 0 to 100 μm is laminated so that its surface protrudes from the surface of the acrylic pressure-sensitive adhesive sheet and covers 12 to 50% of the surface. The gist is an adhesive double-sided pressure-sensitive adhesive sheet.

The photopolymerizable composition containing an alkyl (meth) acrylate as a main component used in the present invention contains an alkyl (meth) acrylate as a main component, is copolymerizable therewith, and obtains an acrylic copolymer. A monomer having a polar group that becomes a crosslinking point, a crosslinkable monomer, a photopolymerization initiator, and the like are added, and a filler, a tackifier resin, and the like may be added as necessary.

The alkyl group of the alkyl (meth) acrylate preferably has 1 to 18 carbon atoms, more preferably 4 to 18 carbon atoms. For example, n-butyl (meth) acrylate, hexyl (meth) acrylate, 2- Ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, n-octyl (meth) acrylate, isononyl (meth) acrylate, lauryl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, isostearyl (meth) acrylate And the like. These alkyl (meth) acrylates may be used alone or in combination of two or more.

Alkyl (meth) acrylate is mainly composed of an alkyl (meth) acrylate having a glass transition temperature (Tg) of -50 ° C. or less as a main component, and a methyl (meth) acrylate in order to balance adhesion and cohesion. A lower alcohol (meth) acrylate such as (meth) acrylate or ethyl (meth) acrylate may be used in combination. In order to impart a high compression modulus to the obtained acrylic pressure-sensitive adhesive sheet, it is effective to increase the content of the monomer having a glass transition temperature (Tg) of the homopolymer as high as possible.

The content of the alkyl (meth) acrylate is preferably from 50 to 99% by weight, more preferably from 70 to 99% by weight of the total monomers. When the content of the alkyl (meth) acrylate is less than 50% by weight, the cohesive strength is increased and the compression modulus is increased, so that the adhesive strength to the adherend is reduced as described later. In addition, the above content is 99
If the content exceeds 10% by weight, the cohesive strength will be low and the adhesive strength will be low.

Examples of the monomer having a polar group include monomers containing a carboxyl group or an acid anhydride such as (meth) acrylic acid, maleic acid, fumaric acid, itaconic acid or anhydrides thereof, (meth) acrylonitrile, N -A nitrogen-containing monomer such as vinylpyrrolidone, N-vinylcaprolactam, acryloylmorpholine, (meth) acrylamide, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate, 2-hydroxyethyl ( Meth) acrylate, 4-
Hydroxy group-containing monomers such as hydroxybutyl (meth) acrylate, polyoxyethylene (meth) acrylate, polyoxypropylene (meth) acrylate, and caprolactone-modified (meth) acrylate.

The content of the monomer having a polar group is preferably 0.99 to 20% by weight of the total monomer. When the content of the monomer having a polar group is less than 0.99% by weight, the degree of crosslinking is small and the cohesive strength is reduced. In addition, the content is 20
If it exceeds 10% by weight, the compression modulus will be high.
As described later, the adhesive strength to the adherend decreases.

When high cohesion is required, a crosslinkable monomer is added. Examples of the crosslinkable monomer include hexanediol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, and pentaerythritol Di (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropane trimethacrylate, allyl (meth)
Examples include acrylate, vinyl (meth) acrylate, divinylbenzene, epoxy acrylate, polyester acrylate, and urethane acrylate.

The content of the crosslinkable monomer is preferably 0.01 to 1% by weight of the total monomer, more preferably 0.01% by weight.
2 to 0.8% by weight. When the content of the crosslinkable monomer is less than 0.01% by weight, the degree of crosslinking is small and the cohesive strength is reduced. On the other hand, when the content exceeds 1% by weight, the cohesive force increases, and the compression modulus increases. In order to impart a high compression modulus to the obtained acrylic pressure-sensitive adhesive sheet, it is effective to increase the degree of crosslinking and increase the gel fraction of the obtained acrylic copolymer, but it is effective to increase the adhesive force and cohesive force. In order to satisfy both, the gel fraction is preferably 5 to 99% by weight,
More preferably, it is 80 to 99% by weight.

The acrylic copolymer may be cross-linked by using an external cross-linking agent in addition to the cross-linkable monomer. Examples of such a cross-linking agent include isocyanate, aziridine-based cross-linking agent and metal complex compound. No.

In addition to the above-mentioned alkyl (meth) acrylate, a monomer having a polar group and a crosslinkable monomer, other monomers copolymerizable with these monomers can also be used. Examples of these other monomers include vinyl acetate, vinyl propionate, styrene, and isobornyl (meth) acrylate. The content of these other monomers is preferably 30% by weight or less based on all the monomers. If the content exceeds 30% by weight, the cohesive strength is increased and the compressive modulus is increased, so that a sufficient adhesive force to the adherend cannot be obtained as described later.

Examples of the photopolymerization initiator include, for example, 4-
(2-hydroxyethoxy) phenyl (2-hydroxy-2-propyl) ketone [manufactured by Ciba Geigy, trade name “Darocur 2959”], α-2-hydroxy-α,
α'-dimethyl-acetophenone (manufactured by Ciba Geigy,
Trade name “Darocure 1173”], methoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone [Ciba Geigy, trade name “Irgacure 65”
1 "], 2-hydroxy-2-cyclohexyl acetophenone [trade name" Irgacure 18 "manufactured by Ciba Geigy Co., Ltd.
4 "], ketals such as benzyldimethyl ketal, and other halogenated ketones, acylphosphinoxides, acylphosphonates, and the like.

The content of the photopolymerization initiator is 10
The amount is preferably 0.01 to 5 parts by weight, more preferably 0.05 to 3 parts by weight, based on 0 parts by weight. Content 0.0
If the amount is less than 1 part by weight, the polymerization conversion rate decreases and only an acrylic copolymer having a strong monomer odor can be obtained. On the other hand, when the content exceeds 5 parts by weight, the amount of generated radicals increases, the molecular weight of the obtained polymer decreases, and the cohesive strength decreases.

Examples of the filler include inorganic hollow fine particles such as glass balloon, shirasu balloon and fly ash balloon, polymethyl methacrylate, acrylonitrile-vinylidene chloride copolymer, polystyrene, and the like.
Examples include organic hollow fine particles made of phenolic resin, inorganic fine particles such as glass beads, silica beads, and synthetic mica, and organic fine particles made of polyethyl acrylate, polyurethane, polyethylene, and polypropylene. Further, as other fillers, various reinforcing fibers, woven or nonwoven fabric, viscosity modifiers, pigments, and the like may be added. Above all, the addition of silica fine particles such as Aerosil and inorganic fine particles such as calcium carbonate is effective in obtaining a high compression modulus of the obtained acrylic pressure-sensitive adhesive sheet.

The viscosity modifier increases the viscosity of the photopolymerizable composition containing an alkyl (meth) acrylate as a main component during photopolymerization and imparts thixotropy to the composition.
It has an effect of favorably dispersing the fine particles of the filler in the photopolymerizable composition. As the viscosity modifier, for example, a solution in which an elastomer such as acrylic rubber, nitrile rubber, styrene-isoprene-styrene copolymer, or a thermoplastic resin such as polymethyl methacrylate (PMMA) or polystyrene is appropriately dissolved in a solvent is used. These solutions may be used by mixing silica, alumina or the like having an average particle size of 5 μm or less. When the inorganic powder such as silica or alumina is subjected to a hydrophobizing treatment, it can be dispersed to primary particles more quickly.

Instead of using the above-mentioned viscosity modifier, a part of the photopolymerizable composition is partially polymerized in advance before adding the photopolymerization initiator to the photopolymerizable composition, so that stripes or the like are formed in the coating step. The required viscosity can be imparted without generating a microgel which causes a defect. The partial polymerization of the photopolymerizable composition for increasing the viscosity is preferably performed in a range of 1.5 to 60% of the total monomer amount.

Examples of the tackifying resin include a rosin resin, a modified rosin resin, a terpene resin, a terpene phenol resin, a C5 and C9 petroleum resin, a cumarone resin, and hydrogenated products thereof. . These tackifying resins may be used alone or in combination of two or more.

Lamps for irradiating the photopolymerizable composition containing alkyl (meth) acrylate as a main component with active light having the above-mentioned structure have an emission distribution at a light wavelength of 450 nm or less. Mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultrahigh-pressure mercury lamps, chemical lamps, black light lamps, microwave-excited mercury lamps, metal halide lamps, and the like. Above all, the chemical lamp efficiently emits light in the active wavelength region of the photopolymerization initiator, and the light absorption of the photopolymerizable composition components other than the photopolymerization initiator in the active wavelength region is small. Since the light sufficiently penetrates into the interior of the adhesive composition, it is suitable for producing a high-thickness pressure-sensitive adhesive sheet.

The irradiation intensity of the actinic ray applied to the photopolymerizable composition is appropriately controlled depending on the use of the obtained pressure-sensitive adhesive sheet. However, the cleavage type photopolymerization initiator having an acetophenone group is used in the photopolymerizable composition. When compounded in a product, the irradiation intensity of light in a wavelength region effective for photocleavage of the photopolymerization initiator (differs depending on the type of photopolymerization initiator, usually 365 to 420 nm) is preferably 0.1 to 100 mW / cm ² .

The photopolymerizable composition is generally formed into a sheet on release paper and polymerized by irradiation with light to form an acrylic copolymer and an acrylic pressure-sensitive adhesive sheet. The light irradiation intensity can be adjusted by a light cut filter as needed,
Excessive heat generated during photopolymerization is cooled by transferring the surface opposite to the light irradiation surface while making contact with the cooling plate surface, and the heat of polymerization causes the release paper for coating and the photopolymerizable composition sheet to expand and contract. As a result, waving and wrinkles occur,
The smoothness of the acrylic pressure-sensitive adhesive sheet surface can be prevented from being impaired.

The photopolymerization is inhibited by oxygen in the reaction vessel and oxygen dissolved in the photopolymerizable composition. Therefore, irradiation with actinic light preferably adds a means for eliminating oxygen inhibition to this process. As such means, for example, the surface of the photopolymerizable composition coated on a film of polyethylene terephthalate or polytetrafluoroethylene subjected to surface release treatment is closely covered with a film subjected to surface release treatment, There is a method of irradiating the photopolymerizable composition with actinic light in this state. or,
There is also a method in which the air in the photopolymerization reaction container is replaced with an inert gas such as nitrogen gas or carbon dioxide gas, and then the active light is irradiated from the irradiation window of the photopolymerization reaction container. In the inert gas replacement method, in order to make the polymerization conversion of the photopolymerizable composition 99.7% or more, the oxygen concentration in the atmosphere in the photopolymerization reaction vessel is preferably 5000 ppm or less, more preferably. Irradiation of actinic rays is performed at an oxygen concentration of 3000 ppm or less.

The acrylic pressure-sensitive adhesive sheet obtained as described above has a compression modulus at 25% compression of 0.1 to 50 kg.
/ Cm ² . In the present invention, the compression elastic modulus at the time of 25% compression is set to the above range. When the compression elastic modulus is less than 0.1 kg / cm ² , the acrylic copolymer becomes too soft, and When positioning with respect to the non-adhesive or slightly adhesive masking member, the adhesive surface of the acrylic pressure-sensitive adhesive sheet cannot be prevented from sticking to the surface of the adherend at the protruding portion of the masking member, and it is difficult to re-peel because it adheres And the compression modulus is 50 kg / cm ²
If it exceeds, the flexibility is not sufficient, so that the adhesive surface of the acrylic pressure-sensitive adhesive sheet is prevented from sticking to the surface of the adherend at the projecting portion of the non-adhesive or slightly adhesive masking member. Positioning can be performed freely, but even if pressure is applied, it is difficult to position the non-sticky or slightly sticky masking member inside the acrylic pressure-sensitive adhesive sheet surface, and it is not possible to obtain a sufficient adhesive force to the adherend. .

The compression modulus at 25% compression is 1
This is a value measured by stacking acrylic pressure-sensitive adhesive sheet test pieces punched into a disc of cm ² , making the thickness about 8 mm, applying a load from above, and measuring the load when compressed by 25%. . The thickness of the acrylic pressure-sensitive adhesive sheet is not particularly limited, but is usually 0.5 to 10 mm.

In the present invention, a non-adhesive or slightly adhesive masking member is laminated on at least one surface of the acrylic pressure-sensitive adhesive sheet so that the surface protrudes from the surface of the acrylic pressure-sensitive adhesive sheet.

The masking member is not particularly limited as long as it is made of a non-sticky or slightly sticky member, and examples thereof include coarsely woven fabric, non-woven fabric, metal mesh, and molded net. Can be The molded net is a net obtained by molding or bonding a material other than fibers or metal, for example, a thermoplastic resin, and the molding method is not particularly limited. As an example of a forming net, a weft-processed orthogonal laminated nonwoven fabric (manufactured by Sekisui Kaisha Co., Ltd., trade name “Sof NA33”: stretched yarn: width 1 mm ×
28 μm thickness, basis weight 12 g / m ² , trade name “SOF NA5
5 ": Stretched yarn: width 1 mm x thickness 38 m, basis weight 17
g / m ² , trade name “Sof HN33”: stretched yarn: width 1
mm × thickness 10 μm, basis weight 10 g / m ² ).

As the slightly tacky masking member, there may be mentioned a non-sticky masking member having a slightly tacky pressure-sensitive adhesive applied to the surface thereof. As the slightly tacky pressure-sensitive adhesive, all pressure-sensitive adhesives used for general protect tapes can be used. For example, ethylene-vinyl acetate copolymer (EVA) -based pressure-sensitive adhesives, EVA / SBS (styrene-butadiene-styrene Polymer) -based pressure-sensitive adhesives, acrylic pressure-sensitive adhesives, acrylic rubber-based pressure-sensitive adhesives, and other special removable adhesives, such as acrylic-based microsphere-shaped pressure-sensitive adhesives and polyoxypropylene-based pressure-sensitive adhesives Are also mentioned.

The above-mentioned slightly tacky adhesive has, for example, an adhesive strength to a stainless steel plate or an adhesive strength to concrete of 50 to 600 g / 25 mm, a glass transition temperature of -60 to -40 ° C., and a gel fraction. Those having 70% by weight or more are preferred.

The non-adhesive or slightly-adhesive masking member is required to protrude from the surface of the acrylic pressure-sensitive adhesive sheet when adjusting the position at the time of sticking, and at the time of pressure bonding, to the inside of the pressure-sensitive adhesive surface and the surface. And loses the above function. Accordingly, the thickness is set in accordance with the material and the shape, but is 10 to 100 μm. When the thickness is less than 10 μm, even if a non-adhesive or slightly adhesive masking member is laminated, the surface of the acrylic pressure-sensitive adhesive sheet tends to stick to the surface of the adherend prior to pressing, and the pressure before pressing is increased. Re-peeling and position adjustment are difficult. Conversely, if the thickness exceeds 100 μm, the position adjustment until final adhesion is easy, but it is difficult to sufficiently adhere the pressure-sensitive adhesive layer surface to the adherend even when pressure is applied.

For example, when a non-adhesive or slightly-adhesive masking member is made of polyethylene net made of woven fine fibers, it is made of a weft-processed laminated nonwoven fabric which is adhesively molded from a stretched yarn having a width of 100 μm or less or slightly wider. In this case, it is about 30 μm.

In the case of a mesh, if the mesh of the mesh is too fine, the adhesive does not sufficiently project and the bonding area may not be sufficiently secured, so that the mesh is as coarse as possible, for example, 10 mesh or less. It is preferable to use As the metal mesh, a brass mesh is preferably used because it is inexpensive and easily available.

When the non-adhesive masking material is composed of a nonwoven fabric orthogonally laminated, it is preferable that the width of the yarn is 0.5 to 5 mm and the interval between the yarns is 1 to 10 mm.
(Shown by basis weight and coverage), and the thickness of the yarn is about 30 μm. This is apparent from the examples described below.
It is because sufficient re-peelability and adhesiveness after pressurization can be obtained by setting the width and thickness of the yarn and the interval between yarns (indicated by the basis weight and the coverage) in the above specific ranges.

If the coverage of the masking member is less than 12%, the removability is reduced and reattachment becomes ineffective, and if the coverage exceeds 50%, the adhesive strength is reduced. Limited to 12-50%.

Hereinafter, the structure of the pressure-sensitive adhesive type double-sided pressure-sensitive adhesive sheet of the present invention will be described with reference to FIGS.

FIG. 1 is a partially cutaway sectional view showing an example of the pressure-sensitive adhesive type double-sided pressure-sensitive adhesive sheet of the present invention. The pressure-sensitive adhesive type double-sided pressure-sensitive adhesive sheet 1 has a non-adhesive or slightly adhesive masking member 5 laminated on one adhesive surface 3 of an acrylic pressure-sensitive adhesive sheet 2. The non-adhesive or slightly adhesive masking member 5 may be provided on the other adhesive surface 4.

In the pressure-bonded double-sided pressure-sensitive adhesive sheet 1, in the state shown in the drawing, a non-adhesive or light-adhesive masking member 5 is laminated so as to protrude from the adhesive surface 3 of the acrylic pressure-sensitive adhesive sheet 2. Therefore, the pressure-sensitive adhesive double-sided pressure-sensitive adhesive sheet 1
Is brought into contact with the adherend surface from the side of the adhesive surface 3,
The adhesive surface 3 does not contact the adherend surface. Therefore, the position of the pressure-sensitive adhesive type double-sided pressure-sensitive adhesive sheet 1 can be freely adjusted in a state where the pressure-sensitive adhesive double-sided pressure-sensitive adhesive sheet 1 is in contact with the adherend surface. In this case, the pressure-sensitive adhesive type double-sided pressure-sensitive adhesive sheet 1 is usually bonded in advance to building materials such as skirting boards and flooring materials on the pressure-sensitive adhesive surface 4 side. After the adhesive sheet 1 is attached, a building material such as a baseboard or a floor material to be attached may be attached to the adhesive surface 4 side.

As described above, since the non-adhesive or slightly-adhesive masking member 5 is present, the pressure-adhesive double-sided adhesive sheet 1 can be freely adjusted in position while being in contact with the surface of the adherend. After the position adjustment is completed,
By pressing the pressure-bonding type double-sided pressure-sensitive adhesive sheet 1 toward the adherend, the pressure-bonding type double-sided pressure-sensitive adhesive sheet 1 can be attached.

FIG. 2 is a cross-sectional view showing a state in which the pressure-sensitive adhesive double-sided pressure-sensitive adhesive sheet of the present invention is adhered to an adherend by applying pressure. By pressing, the acrylic pressure-sensitive adhesive sheet 2 is compressed and deformed, and the non-adhesive or slightly adhesive masking member 5 is moved inward from the adhesive surface 3. On the other hand, compressive stress in the acrylic pressure-sensitive adhesive sheet 2 generated by pressurization causes the acrylic pressure-sensitive adhesive sheet 2 to be pressed against the surface of the adherend 6 from the back surface of the pressure-sensitive adhesive surface 3. Accordingly, the acrylic pressure-sensitive adhesive sheet 2 is pressed against the surface of the adherend 6 by compressive stress and strongly adheres to portions other than the portion where the non-tacky or slightly tacky masking member 5 is laminated.

Therefore, in the pressure-sensitive adhesive type double-sided pressure-sensitive adhesive sheet 1, position adjustment and re-peeling until final determination of the sticking position can be easily performed. It can be firmly adhered to the correct position.

In addition, even when the pressure is applied when the pressure-sensitive adhesive double-sided pressure-sensitive adhesive sheet 1 is wound around a roll or the like,
Since the acrylic pressure-sensitive adhesive sheet 2 has flexibility, the non-tacky or slightly tacky masking member 5 sinks into the pressure-sensitive adhesive surface 3 of the acrylic pressure-sensitive adhesive sheet 2. As a result, the acrylic adhesive sheet 2 returns to its original shape, so that the surface of the non-adhesive or slightly adhesive masking member 5 projects again from the adhesive surface 3 as shown in FIG.

Therefore, the pressure-sensitive adhesive double-sided pressure-sensitive adhesive sheet 1 of the present invention can be provided in a state wound around a take-up roll. There is no loss in performance.

The shape of the non-adhesive or slightly-adhesive masking member 5 is preferably such that the surface of the acrylic pressure-sensitive adhesive sheet 2 is uniformly covered, and the woven cloth has a coarse weave (FIG. 3) or a crosswise laminated nonwoven fabric (FIG. 3). It may be in the form of a grid as in FIG.
It may be a net or a porous sheet in which circular or other appropriate shaped openings are dispersedly formed, such as a synthetic resin sheet having openings with rounded corners (FIG. 5).

The pressure-sensitive adhesive double-sided pressure-sensitive adhesive sheet of the present invention is used as a pressure-sensitive adhesive laminated decorative board which is laminated on the back surface of a decorative board or the like and the non-tacky or slightly tacky masking member is exposed on the surface. be able to. The decorative board is not particularly limited. For example, in addition to building materials such as flooring materials, skirting boards, wall materials, ceiling materials, etc., plate-like materials exhibiting decorative properties in various applications such as vehicle interior materials. A member can be used.

Since the pressure-sensitive adhesive type double-sided pressure-sensitive adhesive sheet of the present invention is constituted as described above, the above-mentioned masking is carried out unless a pressing force is applied to the surface on which the non-tacky or slightly tacky masking member is laminated. The surface of the member is laminated so that it protrudes from the surface of the acrylic pressure-sensitive adhesive sheet, and the surface of the adherend and the surface of the acrylic pressure-sensitive adhesive sheet do not adhere to each other. The positioning can be easily performed with respect to the attachment surface of the adherend.

After the positioning, a pressing force is applied to the surface on which the non-sticky or slightly sticky masking member is laminated. Since the compression elastic modulus at the time of% compression is within the above specific range, the acrylic pressure-sensitive adhesive sheet is buried so as to be located inside the surface of the acrylic pressure-sensitive adhesive sheet, and the pressure-sensitive adhesive surface emerges from the surface. It adheres to the body surface and develops strong adhesive strength.

Further, the pressure-sensitive adhesive double-sided pressure-sensitive adhesive sheet of the present invention can be wound into a roll at the time of production and storage, and immediately after being unwound from the roll at the time of use and developed into a sheet,
Since the surface of the non-adhesive or slightly adhesive masking member protrudes from the adhesive surface of the acrylic adhesive sheet,
At the time of sticking work, the adherend contact surface for positioning can always be slid or re-peeled, and in this state, if the pressure-sensitive adhesive surface of the pressure-sensitive adhesive double-sided pressure-sensitive adhesive sheet is pressure-bonded, A sufficient adhesive strength can be obtained for the body.

[0056]

(Example 1) In a separable flask, 92 parts by weight of 2-ethylhexyl acrylate, 8 parts by weight of acrylic acid, n-
0.02 parts by weight of dodecanethiol, 2,2-dimethyl-
0.2 parts by weight of 2-phenylacetophenone (trade name “Irgacure 651” manufactured by Ciba Geigy) was added,
The mixture was stirred and mixed until uniformly dispersed, and the inside of the separable flask was replaced with nitrogen gas to remove oxygen in the reaction system including dissolved oxygen in the photopolymerizable composition. Next, ultraviolet rays were irradiated using a chemical lamp to partially polymerize the photopolymerizable composition until the viscosity became 2200 cps.

To the partially polymerized photopolymerizable composition, 0.02 parts by weight of hexanediol diacrylate was additionally added, and the mixture was stirred and mixed to obtain a 50 μm-thick release-treated polyethylene terephthalate (PET). It was applied on the film so that the thickness at the end of the polymerization was 1 mm ± 0.1 mm. Further, a PET film of the same quality as described above is coated on the coating film of the partially polymerized photopolymerizable composition in close contact with the above film, and ultraviolet rays are irradiated with a chemical lamp at an irradiation intensity of ² mW / cm ² on the PET film. After adjusting the height of the irradiation device so as to obtain an acrylic pressure-sensitive adhesive sheet, irradiation was performed for 5 minutes. In addition, 25% of acrylic adhesive sheet
The compression modulus at the time of compression was 9 kg / cm ² .

The release paper on one side of the obtained acrylic pressure-sensitive adhesive sheet was peeled off, and as a non-adhesive masking member, a polyethylene weft orthogonally laminated nonwoven fabric (trade name “Sof NA33”, manufactured by Sekisui Kaisha Co., Ltd .: stretched yarn: 1 mm width × thickness) 28 μm, and a basis weight of 12 g / m ² ) to produce a pressure-sensitive adhesive double-sided pressure-sensitive adhesive sheet. The coverage of the pressure-sensitive adhesive type double-sided pressure-sensitive adhesive sheet with the non-adhesive masking member was 26.5.
%Met.

Example 2 Isooctyl acrylate 9
5 parts by weight, acrylic acid 5 parts by weight, n-dodecanethiol 0.02 parts by weight, hydrophilic silica (manufactured by Nippon Aerosil Co., Ltd.
4 parts by weight of trade name “Aerosil 200”) were stirred and mixed with a dissolver type stirrer at 2000 rpm × 4 hours to form a viscous liquid. Further, 0.2 parts by weight of 2,2-dimethyl-2-phenylacetophenone and hexanediol 0.02 parts by weight of acrylate was added and mixed, followed by stirring and mixing, and oxygen was purged with nitrogen gas in a mixer to prepare a photopolymerizable composition. The photopolymerizable composition was coated on a 50 μm-thick release-treated PET film to a thickness of 50 μm at the end of polymerization.
m ± 5 μm, and the following process was carried out in the same manner as in Example 1 to tightly cover a PET film of the same quality as described above, and irradiate UV light on the PET film using a chemical lamp. After adjusting the height of the irradiation device to ² mW / cm ² , irradiation was performed for 5 minutes to produce an acrylic pressure-sensitive adhesive sheet. The compression elastic modulus of the acrylic pressure-sensitive adhesive sheet at 25% compression was 9 kg / cm ² .

The obtained acrylic pressure-sensitive adhesive sheet was used in Example 1.
Was laminated on both sides of the acrylic pressure-sensitive adhesive sheet obtained in the above, to prepare an acrylic pressure-sensitive adhesive sheet having a thickness of 1.1 mm. Furthermore,
A pressure-bonded double-sided pressure-sensitive adhesive sheet was produced by laminating a polyethylene weft orthogonally laminated nonwoven fabric as a non-tacky masking member on one surface of the acrylic pressure-sensitive adhesive sheet in the same manner as in Example 1. The coverage of the pressure-sensitive adhesive double-sided pressure-sensitive adhesive sheet obtained with the non-adhesive masking member was 26.5%.

(Comparative Example 1) Polyethylene weft orthogonally laminated nonwoven fabric of Example 1 (trade name "Sof NA3" manufactured by Sekisui Kabushiki Kaisha, Ltd.)
3 ": Stretched yarn: width 1 mm x thickness 28 m, basis weight 12
g / m ² ), instead of using a polyethylene weft orthogonally cross-laminated nonwoven fabric (trade name “Sof GX44”, manufactured by Sekisui Kaisha Co., Ltd .: stretched yarn: width 3 mm × thickness 50 μm, basis weight 28 g / m ² ) In the same manner as in Example 1, a pressure-adhesive double-sided pressure-sensitive adhesive sheet was produced. In addition, the coverage of the obtained pressure-sensitive adhesive type double-sided pressure-sensitive adhesive sheet with the non-adhesive masking member was 66.7%.

(Comparative Example 2) Polyethylene weft orthogonally cross-laminated nonwoven fabric of Example 1 (trade name "Sof NA3" manufactured by Sekisui Kako Co., Ltd.)
3 ": Stretched yarn: width 1 mm x thickness 28 m, basis weight 12
g / m ² ) instead of polyethylene weft orthogonally laminated nonwoven fabric (stretched yarn: width 2 mm × thickness 30 μm, basis weight 5 g / m)
^A pressure-bonded double-sided PSA sheet was produced in the same manner as in Example 1 except that ² ) was used. The coverage of the pressure-sensitive adhesive double-sided pressure-sensitive adhesive sheet with the non-adhesive masking member was 9.3%.

In order to evaluate the performance of the pressure-sensitive adhesive type double-sided pressure-sensitive adhesive sheet obtained in each of the examples and comparative examples, the initial pressure and the position correcting property were tested by the following methods. The test results are shown in Table 1.

(1) Initial adhesive strength: 20 mm wide and 1 length long on the surface of a test acrylic resin plate manufactured by Nippon Test Panel Co.
A 50 mm pressure-adhesive double-sided pressure-sensitive adhesive sheet is placed at 23 ° C x 65
Under an atmosphere of% RH, the masking member is adhered from the side where it is laminated, and a 2 kg roller is reciprocated once and pressed.
It was left under the above atmosphere for 72 hours. Then, one end of the pressure-sensitive adhesive type double-sided pressure-sensitive adhesive sheet is gripped under the above atmosphere using a tensile tester, and is pulled in a 90 ° direction at a pulling speed of 300 mm / min. Was measured.

(2) Position Correctability: A pressure-sensitive adhesive double-sided pressure-sensitive adhesive sheet on which the masking member is not laminated is pasted on the surface of the test acrylic resin plate, and pasted on the surface of the test acrylic resin plate. Lightly touch the exposed surface of the pressure-bonded double-sided adhesive sheet on which the masking member is laminated to the surface of another acrylic resin plate for testing, and touch the corresponding contact surface by hand to correct the bonding position. A test as to whether or not it is possible to move was performed by a sensory test of a worker who was used to interior work, and evaluated in two stages: ：: sticking position could be corrected, ×: sticking position could not be corrected.

[0066]

[Table 1]

As is clear from Table 1, the pressure-sensitive adhesive type double-sided pressure-sensitive adhesive sheet of the example exhibited excellent performance in both the initial adhesive force and the position correcting property. Can correct the sticking position, but the initial adhesive strength is largely insufficient, and sufficient adhesive strength cannot be expected even after pressure bonding.
Further, the pressure-sensitive adhesive double-sided pressure-sensitive adhesive sheet of Comparative Example 2 had sufficient initial pressure-sensitive adhesive force as in the example, but could not modify the sticking position at all.

[0068]

The pressure-sensitive adhesive double-sided pressure-sensitive adhesive sheet of the present invention
Since it is configured as described above, it is possible to slide the adherend contact surface in a state where the adhesive surface is lightly in contact with the adherend, so that the sticking position can be freely corrected, In addition, if the pressure-sensitive adhesive surface of the pressure-sensitive adhesive-type double-sided pressure-sensitive adhesive sheet is pressure-bonded in this state, sufficient adhesive strength to the adherend can be obtained, so that the structural strong adhesive force is obtained. The double-sided pressure-sensitive adhesive sheet can be widely used for sticking work and can be used with extremely simple working means. Furthermore, the pressure-sensitive adhesive type double-sided pressure-sensitive adhesive sheet of the present invention is manufactured and stored, even if it is wound into a roll, immediately after being unwound from the wound body and expanded into a sheet at the time of use, an acrylic pressure-sensitive adhesive sheet is formed. Since the non-adhesive or slightly adhesive masking member protrudes from the adhesive surface, during the sticking work, it is always possible to slide or re-peel the adherend contact surface for positioning,
Further, if the pressure-sensitive adhesive surface of the pressure-sensitive adhesive type double-sided pressure-sensitive adhesive sheet is pressure-bonded in this state, sufficient bonding strength to the adherend can be obtained.

[0069]

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an example of a pressure-adhesive double-sided pressure-sensitive adhesive sheet of the present invention.

FIG. 2 is a cross-sectional view showing a state in which the pressure-sensitive adhesive double-sided pressure-sensitive adhesive sheet of the present invention is pressure-bonded to an adherend.

FIG. 3 is a plan view showing an example of a non-sticky or slightly sticky masking member.

FIG. 4 is a plan view showing an example of a non-sticky or slightly sticky masking member.

FIG. 5 is a plan view showing an example of a non-sticky or slightly sticky masking member.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pressure-adhesive double-sided adhesive sheet 2 Acrylic adhesive sheet 3, 4 Adhesive surface 5 Non-adhesive or slightly adhesive masking member 6 Adherend

Claims (1)

[Claims] 1. An acrylic polymer obtained by irradiating a photopolymerizable composition containing an alkyl (meth) acrylate as a main component with an actinic ray, and having a compression modulus of 0.1 to 50 kg at 25% compression. / Cm ² , a non-adhesive or slightly adhesive masking member having a thickness of 10 to 100 μm protrudes from the surface of the acrylic pressure-sensitive adhesive sheet on at least one surface of the acrylic pressure-sensitive adhesive sheet.
A pressure-sensitive adhesive type double-sided pressure-sensitive adhesive sheet, which is laminated so as to cover about 50%.