JP5324199B2 - Double-sided adhesive tape - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a double-sided adhesive tape which is excellent in workability and easiness in handling during the work, in a solar battery module. <P>SOLUTION: The double-sided adhesive tape includes an acrylic adhesive layer containing bubbles and/or hollow microspheres, which in turn is characterized by having a friction force of 0.01-1.0 N/cm<SP>2</SP>on at least one of the surfaces of the acrylic adhesive layer, the friction force defined as a stress measured when a 2&times;2 cm sample having a fixed 30 g load fixed thereon is placed on an aluminum plate and is pulled at a rate of 300 mm/min horizontally. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a double-sided pressure-sensitive adhesive tape. More specifically, the present invention relates to a double-sided pressure-sensitive adhesive tape excellent in workability and workability during work.

  A solar cell module is a solar cell panel formed by sealing a silicon cell formed on a glass substrate with ethylene-vinyl acetate (EVA) resin or the like and further providing a back sheet (crystalline silicon type solar cell panel). ) Is incorporated into a frame (see Patent Document 1). And since a solar cell module is used outdoors, it is calculated | required that water does not penetrate | invade in a panel.

  In order to prevent water from entering the panel, for example, a foamed sealing material is placed in a compressed state between the panel and the frame. As described above, it is known that a foam sealing material is attached to the end portion of the panel, and the upper and lower surfaces and end surfaces near the end portion of the panel are covered and then incorporated into the frame (pushing into the frame of the frame) (Patent Document 2). reference). However, in such a method, since the foamed sealing material has tackiness, there is a problem in terms of workability.

JP 2003-110128 A JP 2003-137611 A

  Accordingly, an object of the present invention is to provide a double-sided adhesive tape that is excellent in workability and workability during work such as assembling a panel into a frame after covering the upper and lower surfaces and end surfaces near the panel end in a solar cell module. Is to provide.

  As a result of intensive studies to solve the above-described problems, the present inventors have determined that the horizontal frictional force is predetermined on the adhesive surface of the acrylic adhesive layer containing bubbles and / or hollow microspheres as the adhesive layer. When it was within the range, it was found that sliding can be improved in the horizontal direction and tack can be exhibited in the thickness direction, and the present invention has been completed.

That is, a double-sided adhesive tape having a A acrylic-based pressure-sensitive adhesive layer,
The acrylic pressure-sensitive adhesive layer is an acrylic pressure-sensitive adhesive layer containing bubbles, or an acrylic pressure-sensitive adhesive layer containing bubbles and hollow microspheres,
The amount of bubbles is 5 to 50% by volume with respect to the total volume of the acrylic pressure-sensitive adhesive layer,
In at least one surface of the acrylic pressure-sensitive adhesive layer, a sample of 2 cm × 2 cm with a fixed load of 30g, and placed on an aluminum plate, pulled at a rate of 300 mm / min in the horizontal direction is defined as the stress at that time that frictional force, Ri 0.01~1.0N / cm ² der,
A double-sided pressure-sensitive adhesive tape characterized by being used for a solar cell module is provided.

Further, the present invention has a porous screen at least one surface of A acrylic-based pressure-sensitive adhesive layer,
The acrylic pressure-sensitive adhesive layer is an acrylic pressure-sensitive adhesive layer containing bubbles, or an acrylic pressure-sensitive adhesive layer containing bubbles and hollow microspheres,
The amount of bubbles is 5 to 50% by volume with respect to the total volume of the acrylic pressure-sensitive adhesive layer,
A 2 cm × 2 cm sample with a fixed load of 30 g is placed on an aluminum plate on the surface of the porous screen and pulled at a speed of 300 mm / min in the horizontal direction. 01~1.0N / cm ² der is,
The double-sided pressure-sensitive adhesive tape is used for a solar cell module .

Furthermore, the present invention provides a surface having a porous screen of the acrylic pressure-sensitive adhesive layer, the area ratio of the adhesive portion and the porous screen portion (portion other than the adhesive portion) is, the adhesive portions / the porous screen portion (non-adhesive portion (Part) provides the double-sided pressure-sensitive adhesive tape of 5/95 to 95/5.
Furthermore, this invention provides the said double-sided adhesive tape whose usage-amount of the hollow microsphere in the acrylic adhesive layer containing the said bubble and a hollow microsphere is 5-40 volume%.
Furthermore, the present invention provides the double-sided pressure-sensitive adhesive tape comprising an acrylic polymer in which (meth) acrylic acid alkyl ester and a polar group-containing monomer are used as monomer components constituting the acrylic pressure-sensitive adhesive layer. I will provide a.

  According to the double-sided pressure-sensitive adhesive tape of the present invention, since it has the above-described structure, in the solar cell module, after covering the upper and lower surfaces and the end surface near the panel end, the workability during the work such as incorporation into the frame, etc. Excellent workability.

The double-sided pressure-sensitive adhesive tape (double-sided pressure-sensitive adhesive tape) of the present invention is a double-sided pressure-sensitive adhesive tape having an acrylic pressure-sensitive adhesive layer containing bubbles and / or hollow microspheres, and contains bubbles and / or hollow microspheres. It is defined as the stress at that time when a 2 cm x 2 cm sample with a 30 g load fixed is placed on an aluminum plate and pulled horizontally at a speed of 300 mm / min on at least one surface of the acrylic pressure-sensitive adhesive layer. The frictional force is 0.01 to 1.0 N / cm ² . An adhesive surface having such a frictional force exhibits both slip characteristics and tack characteristics. Hereinafter, the “acrylic pressure-sensitive adhesive layer (pressure-sensitive adhesive) containing bubbles and / or hollow microspheres” may be referred to as “bubble-containing acrylic pressure-sensitive adhesive layer (pressure-sensitive adhesive)”.

In the present invention, a porous screen is usually bonded to the surface of the bubble-containing acrylic pressure-sensitive adhesive layer so that the bubble-containing acrylic pressure-sensitive adhesive layer has the above frictional force and characteristics. That is, in the present invention, a porous screen is provided on at least one surface of the bubble-containing acrylic pressure-sensitive adhesive layer, and a 2 cm × 2 cm sample to which a load of 30 g is fixed is placed on the surface of the porous screen on an aluminum plate. Thus, it is preferable that the frictional force defined as the stress at the time of pulling in the horizontal direction at a speed of 300 mm / min is 0.01 to 1.0 N / cm ² .

  The double-sided pressure-sensitive adhesive tape of the present invention may be a base material-less type having no base material (base material layer), or may be a type with a base material having a base material (base material layer). The pressure-sensitive adhesive surface (pressure-sensitive adhesive layer surface) may be provided by another pressure-sensitive adhesive layer (pressure-sensitive adhesive layer other than the bubble-containing acrylic pressure-sensitive adhesive layer). In the present invention, the term “double-sided pressure-sensitive adhesive tape” includes a sheet-like material, that is, a “double-sided pressure-sensitive adhesive sheet”.

  When the double-sided pressure-sensitive adhesive tape of the present invention is a substrate-less type, for example, a substrate-less double-sided surface composed of a bubble-containing acrylic pressure-sensitive adhesive layer that exhibits a horizontal friction force within a predetermined range on at least one surface It has at least a pressure-sensitive adhesive tape, a bubble-containing acrylic pressure-sensitive adhesive layer that exhibits a horizontal friction force within a predetermined range, and another pressure-sensitive adhesive layer, and has a horizontal direction within a predetermined range of the bubble-containing acrylic pressure-sensitive adhesive layer. Examples thereof include a base-less double-sided pressure-sensitive adhesive tape having a structure in which a surface exhibiting frictional force and a surface provided by another pressure-sensitive adhesive layer provide a pressure-sensitive adhesive surface.

  In addition, as said other adhesive layer, it is possible to use a well-known adhesive, for example, an acrylic adhesive, a rubber adhesive, a vinyl alkyl ether adhesive, a silicone adhesive, a polyester adhesive Agents, polyamide adhesives, urethane adhesives, fluorine adhesives, epoxy adhesives, and the like.

  When the double-sided pressure-sensitive adhesive tape of the present invention is a type with a base material, for example, it has at least a base material and a bubble-containing acrylic pressure-sensitive adhesive layer that exhibits a horizontal friction force within a predetermined range, and has a predetermined range. The double-sided pressure-sensitive adhesive tape with a base material, wherein the surface that exhibits the horizontal friction force within a predetermined range of the bubble-containing acrylic pressure-sensitive adhesive layer that exhibits the horizontal friction force in the inside provides at least one pressure-sensitive adhesive surface Etc.

(Bubble-containing acrylic adhesive layer)
The bubble-containing acrylic pressure-sensitive adhesive layer contains an acrylic polymer [particularly an acrylic polymer containing (meth) acrylic acid ester as a monomer component] as a base polymer (main component). As the main monomer component constituting the acrylic polymer, (meth) acrylic acid alkyl ester ((meth) acrylic acid alkyl ester having a linear or branched alkyl group) can be suitably used. Examples of the (meth) acrylic acid alkyl ester include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, (meth ) Isobutyl acrylate, s-butyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, isopentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate , Octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, (meth) acrylic acid Isodecyl, undecyl (meth) acrylate, dodecyl (meth) acrylate (Meth) acrylic acid tridecyl, (meth) acrylic acid tetradecyl, (meth) acrylic acid pentadecyl, (meth) acrylic acid hexadecyl, (meth) acrylic acid heptadecyl, (meth) acrylic acid octadecyl, (meth) acrylic acid nonadecyl, ( And (meth) acrylic acid C _1-20 alkyl esters such as (meth) acrylic acid eicosyl. Among them, (meth) acrylic acid C _2-14 alkyl ester is preferable, and (meth) acrylic acid C _2-10 alkyl ester is more preferable. The above “(meth) acrylic acid ester” represents “acrylic acid ester” and / or “methacrylic acid ester”, and the same applies to others.

  Examples of (meth) acrylic acid esters other than the above (meth) acrylic acid alkyl esters include cycloaliphatic hydrocarbon groups such as cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, and isobornyl (meth) acrylate. (Meth) acrylic acid ester having aromatic hydrocarbon groups such as (meth) acrylic acid ester and phenyl (meth) acrylate.

  The said (meth) acrylic acid ester can be used individually or in combination of 2 or more types. In addition, since (meth) acrylic acid ester is used as a monomer main component of acrylic polymer, the ratio of (meth) acrylic acid ester [especially (meth) acrylic acid alkyl ester] is, for example, acrylic polymer. Is preferably 60% by weight or more, more preferably 80% by weight or more, based on the total amount of the monomer components for preparing the above.

  In the acrylic polymer, various copolymerizable monomers such as polar group-containing monomers and polyfunctional monomers may be used as monomer components. By using a copolymerizable monomer as the monomer component, for example, the adhesive force to the adherend can be improved, or the cohesive force of the pressure-sensitive adhesive can be increased. The copolymerizable monomers can be used alone or in combination of two or more.

  Examples of the polar group-containing monomer include carboxyl group-containing monomers such as (meth) acrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, and isocrotonic acid, and anhydrides thereof (maleic anhydride and the like). Hydroxyl group-containing monomers such as hydroxyalkyl (meth) acrylate such as hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, and hydroxybutyl (meth) acrylate; acrylamide, methacrylamide, N, N- Amide group-containing monomers such as dimethyl (meth) acrylamide, N-methylol (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide; aminoethyl (meth) acrylate, (meta ) Dimethylaminoethyl acrylate, (meth) acrylic Amino group-containing monomers such as t-butylaminoethyl acid; glycidyl group-containing monomers such as glycidyl (meth) acrylate and methyl glycidyl (meth) acrylate; cyano group-containing monomers such as acrylonitrile and methacrylonitrile N-vinyl-2-pyrrolidone, (meth) acryloylmorpholine, N-vinylpyridine, N-vinylpiperidone, N-vinylpyrimidine, N-vinylpiperazine, N-vinylpyrrole, N-vinylimidazole, N-vinyloxazole Heterocycle-containing vinyl monomers such as (meth) acrylic acid methoxyethyl, (meth) acrylic acid ethoxyethyl and other (meth) acrylic acid alkoxyalkyl monomers; vinyl sulfonate sodium and other sulfonic acid group-containing monomers Body; 2-hydroxyethylacryloylfu Phosphoric acid group-containing monomers such as Sufeto; cyclohexyl maleimide, imide group-containing monomers such as isopropyl maleimide; 2-methacryloyl isocyanate group-containing monomers such as methacryloyloxyethyl isocyanate, and the like. As the polar group-containing monomer, a carboxyl group-containing monomer such as acrylic acid or an anhydride thereof is suitable.

  The amount of the polar group-containing monomer used is 30% by weight or less (for example, 1 to 30% by weight), preferably 3 to 20% by weight, based on the total amount of monomer components for forming the acrylic polymer. . When the usage-amount of a polar group containing monomer exceeds 30 weight%, for example, the cohesion force of an acrylic adhesive will become high too much, and there exists a possibility that the adhesiveness of an adhesive layer may fall. If the amount of the polar group-containing monomer is too small (for example, less than 1% by weight), the effect of copolymerization of these monomers may not be obtained.

  Examples of the polyfunctional monomer include hexanediol di (meth) acrylate, butanediol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, Neopentyl glycol di (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylol methanetri (meth) Examples include acrylate, allyl (meth) acrylate, vinyl (meth) acrylate, divinylbenzene, epoxy acrylate, polyester acrylate, and urethane acrylate.

  The amount of the polyfunctional monomer used is 2% by weight or less (for example, 0.01 to 2% by weight), preferably 0.02 to less than the total amount of monomer components for forming the acrylic polymer. 1% by weight. If the amount of the polyfunctional monomer used exceeds 2% by weight based on the total amount of the monomer components for forming the acrylic polymer, for example, the cohesive force of the pressure-sensitive adhesive becomes too high, and the pressure-sensitive adhesiveness may decrease. . If the amount of the polyfunctional monomer used is too small (for example, less than 0.01% by weight), the effect of copolymerization of these monomers may not be obtained.

  Examples of copolymerizable monomers other than polar group-containing monomers and polyfunctional monomers include vinyl esters such as vinyl acetate and vinyl propionate, and aromatic vinyl compounds such as styrene and vinyltoluene. Olefins or dienes such as ethylene, butadiene, isoprene and isobutylene; vinyl ethers such as vinyl alkyl ether; vinyl chloride and the like.

  The pressure-sensitive adhesive may contain an appropriate additive as necessary. For example, depending on the type of base polymer, a crosslinking agent (for example, polyisocyanate-based crosslinking agent, silicone-based crosslinking agent, epoxy-based crosslinking agent, alkyl etherified melamine-based crosslinking agent, etc.), tackifier (for example, rosin derivative resin) , Polyterpene resin, petroleum resin, oil-soluble phenol resin, etc., solid, semi-solid, or liquid at room temperature), polymerization regulator (such as lauryl mercaptan or thioglycolic acid), plasticizer, filler, anti-aging agent, An appropriate additive such as a colorant (such as a pigment or a dye) may be included. Moreover, when an adhesive is the adhesive containing the below-mentioned bubble and / or a hollow microsphere, it is preferable that the fluorine-type surfactant is contained as an additive. Although the addition amount of these additives is not particularly limited, for example, it is preferably 50 parts by weight or less, more preferably 10 parts by weight or less with respect to 100 parts by weight of all monomer components for forming the acrylic polymer.

  When preparing the acrylic polymer as the base polymer in the above adhesive, use a curing reaction by heat or active energy rays using a polymerization initiator such as a thermal polymerization initiator or a photopolymerization initiator (photoinitiator). can do. Among these, from the viewpoints of shortening the polymerization time and stability of bubbles when bubbles are contained, a curing reaction (photopolymerization) by active energy rays using a photopolymerization initiator can be preferably used. The said polymerization initiator can be used individually or in combination of 2 or more types.

  Examples of the thermal polymerization initiator include azo polymerization initiators [for example, 2,2′-azobisisobutyronitrile, 2,2′-azobis-2-methylbutyronitrile, 2,2′-azobis. (2-methylpropionic acid) dimethyl, 4,4′-azobis-4-cyanovaleric acid, azobisisovaleronitrile, 2,2′-azobis (2-amidinopropane) dihydrochloride, 2,2′-azobis [ 2- (5-methyl-2-imidazolin-2-yl) propane] dihydrochloride, 2,2′-azobis (2-methylpropionamidine) disulfate, 2,2′-azobis (N, N′-di) Methyleneisobutylamidine) dihydrochloride, etc.], peroxide polymerization initiators (eg, dibenzoyl peroxide, tert-butylpermaleate, etc.), red Box-type polymerization initiators and the like. The amount of the thermal polymerization initiator used is not particularly limited as long as it can be conventionally used as a thermal polymerization initiator.

  The photopolymerization initiator is not particularly limited. For example, benzoin ether photopolymerization initiator, acetophenone photopolymerization initiator, α-ketol photopolymerization initiator, aromatic sulfonyl chloride photopolymerization initiator, photo An active oxime photopolymerization initiator, a benzoin photopolymerization initiator, a benzyl photopolymerization initiator, a benzophenone photopolymerization initiator, a ketal photopolymerization initiator, a thioxanthone photopolymerization initiator, and the like can be used.

  Specifically, examples of the benzoin ether photopolymerization initiator include benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isopropyl ether, benzoin isobutyl ether, 2,2-dimethoxy-1,2-diphenylethane- Examples include 1-one and anisole methyl ether. Examples of the acetophenone photopolymerization initiator include 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 1-hydroxycyclohexyl phenyl ketone, 4-phenoxydichloroacetophenone, and 4- (t-butyl). Examples include dichloroacetophenone. Examples of the α-ketol photopolymerization initiator include 2-methyl-2-hydroxypropiophenone and 1- [4- (2-hydroxyethyl) phenyl] -2-methylpropan-1-one. . Examples of the aromatic sulfonyl chloride photopolymerization initiator include 2-naphthalenesulfonyl chloride. Examples of the photoactive oxime photopolymerization initiator include 1-phenyl-1,1-propanedione-2- (o-ethoxycarbonyl) -oxime.

  The benzoin photopolymerization initiator includes, for example, benzoin. Examples of the benzyl photopolymerization initiator include benzyl. Examples of the benzophenone-based photopolymerization initiator include benzophenone, benzoylbenzoic acid, 3,3′-dimethyl-4-methoxybenzophenone, polyvinyl benzophenone, α-hydroxycyclohexyl phenyl ketone, and the like. Examples of the ketal photopolymerization initiator include benzyl dimethyl ketal. Examples of the thioxanthone photopolymerization initiator include thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-diisopropylthioxanthone, dodecylthioxanthone, and the like.

  Although it does not specifically limit as the usage-amount of a photoinitiator, For example, 0.01-5 weight part (preferably 0.05-3 weight) with respect to 100 weight part of all the monomer components for forming an acrylic polymer. Part).

  In activating the photopolymerization initiator, active energy rays are irradiated. Examples of such active energy rays include ionizing radiation such as α rays, β rays, γ rays, neutron rays, electron rays, and ultraviolet rays, and ultraviolet rays are particularly preferable. The irradiation energy of the active energy ray, the irradiation time, etc. are not particularly limited as long as the photopolymerization initiator can be activated to cause the monomer component to react.

  The bubble-containing acrylic pressure-sensitive adhesive layer contains at least one of bubbles or hollow microspheres. For this reason, in this invention, when it compresses and is fixed, sealing performance and water stop performance are exhibited by repulsive stress.

  The amount of bubbles that can be mixed into the bubble-containing acrylic pressure-sensitive adhesive layer can be appropriately selected within a range that does not impair adhesive properties, slipperiness, etc., but is usually 5 to 50 volumes with respect to the total volume of the bubble-containing acrylic pressure-sensitive adhesive layer. % (Preferably 10 to 40% by volume, more preferably 12 to 30% by volume). When the amount of bubbles is less than 5% by volume, it is difficult to obtain stress relaxation properties, and even when compressed and fixed, it may be difficult to exert sealing performance and water stopping performance due to repulsive stress. On the other hand, if it exceeds 50% by volume, bubbles penetrating the pressure-sensitive adhesive layer may be formed, resulting in poor adhesion or the bubble-containing acrylic pressure-sensitive adhesive layer being too soft.

  Basically, it is desirable that the bubbles mixed in the bubble-containing acrylic pressure-sensitive adhesive layer are closed-cell type bubbles, but even if closed-cell type bubbles and open-cell type bubbles are mixed. Good.

  In addition, such bubbles usually have a spherical shape, but may have an irregular spherical shape. In the said bubble, it does not specifically limit as the average bubble diameter (diameter), For example, it can select from the range of 1-1000 micrometers (preferably 10-500 micrometers, More preferably, 30-300 micrometers).

  The gas component contained in the bubbles (gas component forming bubbles; sometimes referred to as “bubble-forming gas”) is not particularly limited, and air, in addition to an inert gas such as nitrogen, carbon dioxide, and argon. Various gas components such as can be used. As the bubble forming gas, when a reaction such as a polymerization reaction is performed after mixing the bubble forming gas, it is important to use a gas that does not inhibit the reaction. As the bubble forming gas, nitrogen is preferable from the viewpoint of not inhibiting the reaction and from the viewpoint of cost.

  By using a hollow microsphere as one of the components of the bubble-containing acrylic pressure-sensitive adhesive layer, for example, the strength against tension, bending and impact can be increased, and the workability can be improved. The hollow microspheres can be used alone or in combination of two or more.

  The hollow microspheres may be hollow inorganic microspheres or hollow organic microspheres. Specifically, the hollow inorganic microspheres in the hollow microspheres include, for example, glass hollow balloons such as hollow glass balloons; metal compound hollow balloons such as hollow alumina balloons; hollow ceramic balloons and the like. Examples include porcelain hollow balloons. Examples of the hollow organic microspheres include resin hollow balloons such as hollow acrylic balloons and hollow vinylidene chloride balloons.

  Although it does not restrict | limit especially as a particle size (average particle diameter) of a hollow microsphere, For example, it can select from the range of 1-500 micrometers (preferably 5-200 micrometers, More preferably, 10-100 micrometers).

The specific gravity of the hollow microspheres is not particularly limited, for example, 0.1 to 0.8 g / cm ³ (preferably 0.12 / cm ³⁾ can be selected from the range of. When the specific gravity of the hollow microspheres is smaller than 0.1 g / cm ³ , when the hollow microspheres are mixed, the floating becomes large and it becomes difficult to uniformly disperse, whereas from 0.8 g / cm ³ If it is too large, it becomes expensive and cost increases.

  The amount of hollow microspheres used is not particularly limited. For example, it is 5 to 50% by volume (volume%), preferably 10 to 50% by volume, more preferably, based on the total volume of the bubble-containing acrylic pressure-sensitive adhesive layer. Can be selected from a range of 15 to 40% by volume. When the usage amount of the hollow microspheres is less than 5% by volume, the effect of adding the hollow microspheres may be reduced. On the other hand, when the usage amount exceeds 50% by volume, Adhesive strength may be reduced.

  The pressure-sensitive adhesive composition for forming the bubble-containing acrylic pressure-sensitive adhesive layer used in the present invention is a monomer component (for example, (meth) acrylic acid ester) that forms the acrylic polymer, a polymerization initiator, and various additions. It can prepare by mixing an agent etc. using a well-known method. Moreover, you may polymerize a monomer component partially as needed, such as viscosity adjustment. Specific examples of the preparation method (in the case of photopolymerization) include, for example, the following procedures. (I) preparing a monomer mixture by mixing a monomer component (for example, (meth) acrylic acid ester or other copolymerizable monomer) and a photopolymerization initiator for forming a base polymer; Photopolymerization (for example, ultraviolet polymerization) is performed on the monomer mixture to prepare a composition (syrup, syrup-like composition) in which only a part of the monomer components is polymerized. Next, (iii) the obtained syrup is blended with hollow microspheres, a fluorosurfactant and other additives as necessary. Furthermore, when the pressure-sensitive adhesive contains bubbles, a bubble-containing pressure-sensitive adhesive composition can be obtained by introducing and mixing the bubbles into the formulation obtained in (iv) (iii). In addition, the method for preparing the bubble-containing pressure-sensitive adhesive composition is not limited to this. For example, when preparing the syrup, a fluorine-based surfactant or hollow microspheres may be blended in advance during monomer mixing. It may be a preparation method.

  When air bubbles are included, from the viewpoint of stably mixing the air bubbles in the pressure-sensitive adhesive layer, for example, as in the above preparation method, the air bubbles are mixed and mixed as the last component in the pressure-sensitive adhesive composition. It is preferable to make it. Further, from the viewpoint of stably mixing the bubbles, it is preferable to increase the viscosity of the composition before the bubbles are mixed (for example, the composition obtained in (iii) above). Although it does not specifically limit as a viscosity of the formulation before mixing a bubble, For example, 5-50 Pa.s (BH viscometer, rotor: No.5 rotor, rotation speed: 10 rpm, measurement temperature: 30 degreeC) is preferable. More preferably, it is 10 to 40 Pa · s. When the viscosity is less than 5 Pa · s, the viscosity is too low and the mixed bubbles may immediately coalesce and escape from the system. When the viscosity exceeds 50 Pa · s, the viscosity is too high and the adhesive layer is applied. It may be difficult to form by work. In addition, the said viscosity can be adjusted with the method of mix | blending various polymer components, such as an acrylic rubber and a thickening additive, the method of partially polymerizing the monomer component for forming a base polymer, etc., for example.

  In the method for preparing the bubble-containing pressure-sensitive adhesive composition, the method for mixing the bubbles is not particularly limited, and a known bubble mixing method can be used. For example, as an example of a device, a stator having a large number of fine teeth on a disk having a through-hole at the center, and a stator having a fine tooth on the disk facing the stator with the teeth. An apparatus including a rotor may be used. In this apparatus, a composition for mixing bubbles between teeth on the stator and teeth on the rotor is introduced, and a gas component (bubble forming gas) for forming bubbles through the through-hole while rotating the rotor at high speed is introduced. By introducing, a bubble-containing pressure-sensitive adhesive composition in which a bubble-forming gas is finely dispersed and mixed can be obtained.

  In order to suppress or prevent the coalescence of bubbles, it is preferable to continuously perform from the mixing of bubbles to the formation of the pressure-sensitive adhesive layer as a series of steps. That is, it is preferable to prepare a bubble-containing pressure-sensitive adhesive composition by mixing bubbles as described above, and then to form a bubble-containing acrylic pressure-sensitive adhesive layer using the pressure-sensitive adhesive composition.

  The bubble-containing acrylic pressure-sensitive adhesive layer is formed by applying the pressure-sensitive adhesive composition on an appropriate support to form a coating layer, and curing the layer (for example, photocuring by irradiation with active energy rays). It is formed.

  The thickness of the bubble-containing acrylic pressure-sensitive adhesive layer is not particularly limited, and is preferably, for example, 100 to 3000 μm, more preferably 400 to 2000 μm, and still more preferably 400 to 1200 μm. When the thickness is less than 100 μm, the adhesiveness may be lowered. On the other hand, when the thickness is more than 3000 μm, the module may not fit.

(Porous screen)
The porous screen is bonded to the pressure-sensitive adhesive surface of the bubble-containing acrylic pressure-sensitive adhesive layer. The pressure-sensitive adhesive property is controlled on the pressure-sensitive adhesive surface to which the porous screen is bonded, and the thickness direction (the bubble-containing acrylic type) The tack property in the thickness direction of the pressure-sensitive adhesive layer) and the sliding property in the horizontal direction (direction perpendicular to the thickness direction of the bubble-containing acrylic pressure-sensitive adhesive layer) can be combined.

  The porous screen is a porous screen, that is, a porous (or perforated) sheet. In the present invention, the porous screen includes a net-like material.

  Specific examples of such a porous screen are not particularly limited, and examples thereof include nets (net-like objects such as plastic nets, fiber nets, metal thread nets, etc.), woven fabrics, non-woven fabrics, and papers. Further, for example, a plastic sheet, a thin metal sheet, a woven fabric, a non-woven fabric, paper, or the like (such a sheet having a hole) may be used. Among these, a sheet having a net or a hole is preferable, and a net is particularly preferable.

  The shape of the hole or mesh of the porous screen is not particularly limited as long as the above characteristics can be exhibited. For example, the shape is triangular, quadrangular (for example, square, rectangular, rhombus, trapezoid), circular (for example, perfect circle, perfect circle). Near a circle, an ellipse, etc.). Moreover, the indefinite shape similar to the said shape may be sufficient. In addition, all the holes or mesh shapes may be the same, or may be different for each hole.

  The thickness of the porous screen is not particularly limited as long as it exhibits the above characteristics, but is preferably, for example, 10 to 500 μm, and preferably 50 to 150 μm. If the thickness is less than 10 μm, the slipperiness may be deteriorated. On the other hand, if the thickness exceeds 500 μm, the adhesiveness and the slipperiness may not be compatible.

  When the porous screen is a net, the material is not particularly limited, and examples thereof include synthetic resins (plastics) such as nylon, polyethylene, polypropylene, and polyester, natural fibers, and metal fibers.

The basis weight is not particularly limited, but is preferably 1.0 to 70 g / m ² , and preferably 2.0 to 70 g / m ² from the viewpoint of coexistence of adhesiveness and slipperiness on the adhesive surface to which the porous screen is bonded. 20 g / m ² .

  The size of the mesh is not particularly limited, but is preferably 5 pieces / inch to 50 pieces / inch, preferably 20 pieces / inch from the viewpoint of achieving both adhesion and slipperiness on the adhesive surface on which the porous screen is bonded. Inch to 40 pieces / inch.

  Examples of such a commercially available net include a trade name “Net ND20” manufactured by Daisen Corporation.

  In the case where the porous screen is a sheet having holes, the material is not particularly limited, but plastic and non-woven fabric are preferable from the viewpoint of achieving both adhesiveness and slipperiness on the adhesive surface on which the porous screen is bonded.

  The size of the hole of the porous screen is not particularly limited as long as the above characteristics can be exhibited, and the size of the hole may be common or may be different for each hole. The size of such a hole is, for example, about 500 μm to 10 mm at the largest portion of the hole.

  The distribution of the pores of the porous screen is not particularly limited as long as the above characteristics can be exhibited, and may be concentrated in a certain region or may be dispersed as a whole.

  The distance between the holes of the porous screen is not particularly limited and may be constant or may not be constant.

  In the present invention, the pressure-sensitive adhesive surface covered with the porous screen of the bubble-containing acrylic pressure-sensitive adhesive layer has both tack and slipperiness. More specifically, tackiness is exhibited in the thickness direction of the bubble-containing acrylic pressure-sensitive adhesive layer having a porous screen, and the horizontal direction of the bubble-containing acrylic pressure-sensitive adhesive layer having a porous screen (a direction perpendicular to the thickness direction). Then it shows slipperiness. Hereinafter, the characteristics will be described with reference to FIG. 1, FIG. 2, and FIG. 1, 2, and 3, as the porous screen, the mesh has a square shape, but the shape of the mesh is not limited to the square shape.

  FIG. 1 shows a schematic top view of a bubble-containing acrylic pressure-sensitive adhesive layer having a porous screen on one pressure-sensitive adhesive surface, and FIG. 2 shows a bubble-containing acrylic pressure-sensitive adhesive layer having a porous screen on one pressure-sensitive adhesive surface in FIG. The schematic sectional drawing of an AA cross section is shown. 1 and 2, 1 is a bubble-containing acrylic pressure-sensitive adhesive layer, and 2 is a porous screen. 1 and 2 also show a substrate-less type double-sided pressure-sensitive adhesive tape composed only of a bubble-containing acrylic pressure-sensitive adhesive layer having a porous screen only on one pressure-sensitive adhesive surface.

  FIG. 3 is a schematic cross-sectional view of a state in which a bubble-containing acrylic pressure-sensitive adhesive layer having a porous screen on one adhesive surface is in contact with a contact object in a non-pressurized state on the surface provided with the porous screen. ), And a schematic cross-sectional view (3-2) of a state in which the bubble-containing acrylic pressure-sensitive adhesive layer having a porous screen on one adhesive surface is in contact with a contact object in a pressurized state on the surface provided with the porous screen. Show. In FIG. 3, 1 is a bubble-containing acrylic adhesive layer, 2 is a porous screen, and 3 is a contact.

  In the pressure-sensitive adhesive surface covered with the porous screen, the above-mentioned characteristics are exhibited because the porous screen 2 is partially embedded in the bubble-containing acrylic pressure-sensitive adhesive layer 1 in a non-pressurized state (see FIG. 2). In FIG. 2, the porous screen 2 protrudes from the surface of the bubble-containing acrylic pressure-sensitive adhesive layer 1, and the contact with the contact object 3 on the surface of the bubble-containing acrylic pressure-sensitive adhesive layer 2 is obstructed. On the other hand, in a pressurized state (a state in which the contact object 3 is in contact with a sufficient contact pressure), the porous screen 2 bites into the bubble-containing pressure-sensitive adhesive layer 1, As a result, the bubble-containing acrylic pressure-sensitive adhesive layer 1 is deformed and the porous screen 2 is also compressed and deformed, and the bubble-containing acrylic pressure-sensitive adhesive layer 1 rises at the mesh of the porous screen 2 and passes through the mesh. Bubble-containing acrylic pressure-sensitive adhesive layer 1 that is to contact the contact product 3 (see FIG. 3 (3-2)).

  The degree of burying the porous screen in the non-pressurized state or the pressurized state is not particularly limited as long as the above characteristics can be exhibited.

  In the adhesive surface covered with the porous screen of the bubble-containing acrylic adhesive layer, the area ratio between the adhesive part and the porous screen part (parts other than the adhesive part) [for example, when using a net as the porous screen, The area ratio to the net part (parts other than the adhesive part) is 5/95 to 95 for the adhesive part / porous screen part from the viewpoint of compatibility between adhesiveness and sliding property, and from the viewpoint of adhesiveness and sliding property. / 5 is preferable, and preferably 10/90 to 90/10.

  Regarding the area ratio between the adhesive part and the porous screen part, the surface covered with the porous screen (20 mm × 20 mm) is enlarged (for example, about 16 times), and the resulting copy is used as the adhesive part and the porous screen part with the scissors part. Carve out. The weight of the cut sample paper piece was measured, and the area ratio was defined from the weight ratio.

In the present invention, a 2 cm × 2 cm sample in which a load of 30 g is fixed on at least one surface of the bubble-containing acrylic pressure-sensitive adhesive layer is applied to an aluminum plate (trade name “SK-A aluminum plate 1050P” manufactured by Sumitomo Light Metal Co., Ltd.). Then, it is pulled at a speed of 300 mm / min in the horizontal direction, and the frictional force defined as the stress at that time is 0.01 to 1.0 N / cm ² , preferably 0.01 to 0.5 N / cm ^2. It is. If the frictional force exceeds 1.0 N / cm ² , a problem may occur in terms of slipperiness.

  In the present invention, the pressure sensitive adhesiveness is controlled by laminating the porous screen, and the sliding property in the horizontal direction on the pressure-sensitive adhesive surface covered with the porous screen is improved. It is preferable to have a frictional force. That is, a 2 cm × 2 cm sample in which a load of 30 g was fixed to the bubble-containing acrylic adhesive layer was placed on an aluminum plate on the surface of the porous screen and pulled at a speed of 300 mm / min in the horizontal direction. It is important that the frictional force defined as is within the above range.

  In the present invention, the adhesive strength (180 ° peel peeling, aluminum plate, tensile speed 300 mm / min) on the adhesive surface covered with the porous screen of the bubble-containing acrylic adhesive layer is not particularly limited. From the point of coexistence with slipperiness, it is preferably 0.1 to 50 (N / 20 mm), preferably 0.1 to 20 (N / 20 mm), more preferably 0.2 to 10 (N / 20 mm).

That is, a double-sided pressure-sensitive adhesive tape having a bubble-containing acrylic pressure-sensitive adhesive layer, and a 2 cm × 2 cm sample with a 30 g load fixed on at least one surface of the bubble-containing acrylic pressure-sensitive adhesive layer is placed on an aluminum plate. The frictional force defined as the stress at the time of pulling in the horizontal direction at a speed of 300 mm / min is 0.01 to 1.0 N / cm ² and the adhesive force (180 ° peel peeling, against aluminum plate, A double-sided pressure-sensitive adhesive tape having a tensile speed of 300 mm / min) of 0.1 to 50 (N / 20 mm) has both slipperiness and tack on the pressure-sensitive adhesive surface.

(Release liner)
The pressure-sensitive adhesive surface (pressure-sensitive adhesive layer surface) of the double-sided pressure-sensitive adhesive tape of the present invention may be protected by a release liner (separator, release film) until use. Each pressure-sensitive adhesive surface of the double-sided pressure-sensitive adhesive tape may be protected by two release liners, or may be wound in a roll shape with one release liner whose both surfaces are release surfaces. It may be protected. The release liner is used as a protective material for the pressure-sensitive adhesive layer, and is peeled off when being applied to an adherend.

  As such a release liner, a conventional release paper or the like can be used, and is not particularly limited. For example, a substrate having a release treatment layer, a low-adhesive substrate made of a fluoropolymer, and a low adhesion made of a nonpolar polymer. Can be used. Examples of the low-adhesive substrate made of a fluorine-based polymer include plastic films and papers surface-treated with a release treatment agent such as silicone-based, long-chain alkyl-based, fluorine-based, and molybdenum sulfide. Examples of the fluorine-based polymer of a low-adhesive substrate made of a fluorine-based polymer include polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinyl fluoride, polyvinylidene fluoride, tetrafluoroethylene / hexafluoropropylene copolymer, chloro Examples include fluoroethylene / vinylidene fluoride copolymers. Examples of the nonpolar polymer of the low-adhesive substrate made of a nonpolar polymer include olefin resins (for example, polyethylene and polypropylene). The release liner can be formed by a known or common method. Further, the thickness of the release liner is not particularly limited.

(Other layers)
The double-sided pressure-sensitive adhesive tape of the present invention may have other layers (for example, an intermediate layer, an undercoat layer, etc.) as long as the effects of the present invention are not impaired.

(Base material)
The base material in the case where the double-sided pressure-sensitive adhesive tape of the present invention is a type with a base material is not particularly limited. For example, a paper-based base material such as paper; a fiber-based base material such as cloth, nonwoven fabric, or net (as a raw material thereof) Is not particularly limited, and, for example, Manila hemp, rayon, polyester, pulp fiber, and the like can be selected as appropriate); metal-based substrates such as metal foils and metal plates; plastic-based substrates such as plastic films and sheets Rubber base materials such as rubber sheets; foams such as foam sheets, and laminates thereof (for example, laminates of plastic substrates and other substrates, and laminates of plastic films (or sheets)); Etc.) can be used. As the substrate, a plastic substrate such as a plastic film or sheet can be suitably used. As a material in such a plastic film or sheet, for example, an α-olefin such as polyethylene (PE), polypropylene (PP), ethylene-propylene copolymer, ethylene-vinyl acetate copolymer (EVA) or the like is used as a monomer component. Olefin resin: Polyester resin such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT); polyvinyl chloride (PVC); vinyl acetate resin; polyphenylene sulfide (PPS); polyamide (Nylon), amide resins such as wholly aromatic polyamide (aramid); polyimide resins; polyether ether ketone (PEEK). These materials can be used alone or in combination of two or more.

  In addition, when a plastic-type base material is used as a base material, you may control deformability, such as elongation rate, by extending | stretching process etc. Moreover, as a base material, when a bubble containing acrylic adhesive layer is formed by hardening by an active energy ray, it is preferable to use what does not inhibit permeation | transmission of an active energy ray.

  The surface of the substrate is chemically treated with conventional surface treatments such as corona treatment, chromic acid treatment, ozone exposure, flame exposure, high-voltage impact exposure, ionizing radiation treatment, etc., in order to improve adhesion to the acrylic adhesive layer. Alternatively, oxidation treatment or the like by a physical method may be performed, or coating treatment or the like by an undercoat agent or a release agent may be performed.

  The thickness of the base material can be appropriately selected according to the strength, flexibility, purpose of use, and the like. For example, it is generally 1000 μm or less (for example, 1 to 1000 μm), preferably 1 to 500 μm, more preferably 3 to 300 μm. However, it is not limited to these. In addition, the base material may have any form of a single layer or a lamination.

  The production method of the double-sided pressure-sensitive adhesive tape of the present invention is not particularly limited. For example, a double-sided pressure-sensitive adhesive tape having a bubble-containing acrylic pressure-sensitive adhesive layer covered with a porous screen can be obtained by a known / conventional method. After obtaining the layer, it can be produced by laminating a porous screen on the surface of the bubble-containing acrylic pressure-sensitive adhesive layer.

  More specifically, the base-less double-sided pressure-sensitive adhesive tape composed only of the bubble-containing acrylic pressure-sensitive adhesive layer having a porous screen was prepared by, for example, a cell-containing acrylic pressure-sensitive adhesive layer by a known / conventional method. Then, it can produce by providing a porous screen on the surface of this bubble-containing acrylic adhesive layer.

  In addition, a double-sided pressure-sensitive adhesive tape with a base material composed of a bubble-containing acrylic pressure-sensitive adhesive layer having a porous screen, another pressure-sensitive adhesive layer (pressure-sensitive adhesive layer other than the bubble-containing acrylic pressure-sensitive adhesive layer) and a base material, A bubble-containing acrylic pressure-sensitive adhesive layer is obtained on one surface of a substrate by a known / conventional method, and a porous screen is adhered to the surface of the bubble-containing acrylic pressure-sensitive adhesive layer, thereby containing a bubble screen. It can be produced by providing an acrylic pressure-sensitive adhesive layer and further providing another pressure-sensitive adhesive layer on the other surface of the substrate by a known / conventional method.

  The double-sided pressure-sensitive adhesive tape of the present invention exhibits both sliding properties and tackiness on a pressure-sensitive adhesive surface (for example, a bubble-containing acrylic pressure-sensitive adhesive layer surface covered with a porous screen) whose friction force is controlled.

  In the double-sided pressure-sensitive adhesive tape of the present invention, using such characteristics, the slipperiness on the adhesive surface whose frictional force is controlled is utilized, and the slipperiness is utilized in a portion where it is not desired with respect to a specific adherend. Thus, it can be suitably used for a specific joining application in which only a desired portion is joined using a tack without joining.

  For example, by using a double-sided pressure-sensitive adhesive tape composed of only a bubble-containing acrylic pressure-sensitive adhesive layer in which one adhesive surface is covered with a porous screen and the other adhesive surface is not covered with a porous screen, the double-sided adhesive tape By adhering the adhesive surface not covered with the porous screen to one member, and pasting the member with the double-sided adhesive tape on the bottom of the concave portion of the member having the other concave portion. One member and the concave portion of the member having the other concave portion can be joined with good workability. This is because the adhesive surface covered with the porous screen is exposed and covered with the porous screen in the member in which the double-sided adhesive tape is attached in a form in contact with the adhesive surface not covered with the porous screen. In the adhesive surface, even if the adhesive surface and the member are in contact with each other except for a desired portion, the adhesive layer does not pass through the porous screen in the non-pressurized state (the state where the contact pressure is low), and slipperiness It is to demonstrate.

  If the double-sided pressure-sensitive adhesive tape of the present invention is used, for example, when manufacturing a solar cell module, the upper and lower surfaces and the end surface in the vicinity of the panel end can be covered with good workability and workability and then incorporated into the frame. Moreover, since it can exist in the compressed state after solar cell module manufacture, the water stop performance by a bubble structure is exhibited and the penetration | invasion of the water into a panel can be prevented. For this reason, the double-sided pressure-sensitive adhesive tape of the present invention can be suitably used for a solar cell module.

  Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples.

(Use example 1 of porous screen)
As a porous screen, a plastic net (trade name “Net ND20” manufactured by Daisen, thickness: 110 μm, weaving shape, basis weight: 6.6 g / m ² , mesh size—vertical: 23 / inch, horizontal: 39 / Inch) was used.

(Use example 2 of porous screen)
As a porous screen, perforated non-woven fabric (“non-woven perforated product of special mesh base paper A” (manufactured by Nippon Paper Industries Co., Ltd.), thickness: 70 μm, hole shape: circular, hole diameter: 4 mmφ, basis weight: 16 g / m ² ) was used.

(Usage example 3 of porous screen)
As a porous screen, a perforated nonwoven fabric (“nonwoven fabric perforated shape of special mesh base paper B” (manufactured by Nippon Paper Industries Co., Ltd.), thickness: 60 μm, hole shape: circular, hole diameter: 3 mmφ, basis weight: 16 g / m ² ) was used.

Example 1
A monomer mixture in which 90 parts by weight of 2-ethylhexyl acrylate and 10 parts by weight of acrylic acid were mixed as a monomer component, a photopolymerization initiator [trade name “Irgacure 651” (manufactured by Ciba Japan)]: 0. 05 parts by weight, photopolymerization initiator [trade name “Irgacure 184” (manufactured by Ciba Japan)]: After blending 0.05 part by weight, viscosity (BH viscometer, No. 5 rotor, 10 rpm, measurement temperature: A composition (partially polymerized product, syrup) partially polymerized was produced by irradiating with ultraviolet rays until 30 ° C.) reached about 15 Pa · s. This syrup: 100 parts by weight, a photopolymerization initiator [trade name “Irgacure 651” (manufactured by Ciba Japan)]: 0.04 parts by weight, 1,6-hexanediol diacrylate: 0.1 parts by weight, interface Activator [trade name “Megafac F-477” manufactured by DIC Corporation]: 0.7 parts by weight, and carbon black: 0.02 parts by weight were added. Furthermore, a hollow glass balloon (trade name “Cell Star Z-27” manufactured by Tokai Kogyo Co., Ltd.) was added at a rate of 30% by volume with respect to the total volume of the syrup to prepare an adhesive precursor. In addition, the whole volume of the hollow glass balloon in an adhesive precursor is about 23 volume% with respect to the whole volume of this adhesive precursor. The pressure-sensitive adhesive precursor is opposed to a stator having a large number of fine teeth on a disk having a through-hole in the center and a stator having teeth, and fine teeth similar to the stator are formed on the disk. Nitrogen was introduced and air bubbles were mixed using an apparatus equipped with a rotor attached. The amount of bubbles mixed was introduced so as to be about 15% by volume with respect to the total volume of the discharged liquid material to obtain a bubble-containing pressure-sensitive adhesive composition.
A polyethylene terephthalate base material in which the bubble-containing pressure-sensitive adhesive composition is led to a wet-laminated roll coater with a tube (diameter: 19 mm, length: about 1.5 m), and two surfaces are peeled. The bubble-containing pressure-sensitive adhesive composition was applied between the release-treated surfaces so that the thickness after drying and curing was 1.2 mm. That is, the bubble-containing pressure-sensitive adhesive composition is sandwiched between polyethylene terephthalate substrates.
Next, ultraviolet rays having an illuminance of 5 mW / cm ² are irradiated from both sides for 4 minutes to cure the bubble-containing pressure-sensitive adhesive composition, thereby producing a pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer (bubble-containing pressure-sensitive adhesive layer). did.
The polymer polymerization rate of the obtained tape was 98.9% by weight.
The plastic net of (Porous Screen Use Example 1) is bonded to one adhesive surface of the adhesive tape using a 4-axis laminator so that the net shape of the net is uniform, and one adhesive surface is a net. An adhesive tape having a covered bubble-containing adhesive layer was obtained. On the surface of the bubble-containing pressure-sensitive adhesive layer having a net, the area ratio (occupancy) between the pressure-sensitive adhesive portion and the net portion (portion other than the pressure-sensitive adhesive portion) was 78% for the pressure-sensitive adhesive portion and 22% for the net portion.

(Example 2)
A monomer mixture in which 90 parts by weight of 2-ethylhexyl acrylate and 10 parts by weight of acrylic acid were mixed as a monomer component, a photopolymerization initiator [trade name “Irgacure 651” (manufactured by Ciba Japan)]: 0. 05 parts by weight, photopolymerization initiator [trade name “Irgacure 184” (manufactured by Ciba Japan)]: After blending 0.05 part by weight, viscosity (BH viscometer, No. 5 rotor, 10 rpm, measurement temperature: A composition (partially polymerized product, syrup) partially polymerized was produced by irradiating with ultraviolet rays until 30 ° C.) reached about 15 Pa · s. This syrup: 100 parts by weight, a photopolymerization initiator [trade name “Irgacure 651” (manufactured by Ciba Japan)]: 0.04 parts by weight, 1,6-hexanediol diacrylate: 0.1 parts by weight, interface Activator [trade name “Megafac F-477” manufactured by DIC Corporation]: 0.7 parts by weight, and carbon black: 0.02 parts by weight were added. Furthermore, a hollow glass balloon (trade name “Cell Star Z-27” manufactured by Tokai Kogyo Co., Ltd.) was added at a rate of 30% by volume with respect to the total volume of the syrup to prepare an adhesive precursor. In addition, the whole volume of the hollow glass balloon in an adhesive precursor is about 23 volume% with respect to the whole volume of this adhesive precursor. The pressure-sensitive adhesive precursor is opposed to a stator having a large number of fine teeth on a disk having a through-hole in the center and a stator having teeth, and fine teeth similar to the stator are formed on the disk. Nitrogen was introduced and air bubbles were mixed using an apparatus equipped with a rotor attached. The amount of bubbles mixed was introduced so as to be about 15% by volume with respect to the total volume of the discharged liquid material to obtain a bubble-containing pressure-sensitive adhesive composition.
A polyethylene terephthalate base material in which the bubble-containing pressure-sensitive adhesive composition is led to a wet-laminated roll coater with a tube (diameter: 19 mm, length: about 1.5 m), and two surfaces are peeled. The bubble-containing pressure-sensitive adhesive composition was applied between the release-treated surfaces so that the thickness after drying and curing was 1.2 mm. That is, the bubble-containing pressure-sensitive adhesive composition is sandwiched between polyethylene terephthalate substrates.
Next, ultraviolet rays having an illuminance of 5 mW / cm ² are irradiated from both sides for 4 minutes to cure the bubble-containing pressure-sensitive adhesive composition, thereby producing a pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer (bubble-containing pressure-sensitive adhesive layer). did.
The polymer polymerization rate of the obtained tape was 98.9% by weight.
A bubble-containing pressure-sensitive adhesive in which a perforated nonwoven fabric (porous screen use example 2) is bonded to one adhesive surface of the adhesive tape using a four-axis laminator and one adhesive surface is covered with a perforated nonwoven fabric An adhesive tape having an agent layer was obtained. On the surface of the bubble-containing pressure-sensitive adhesive layer having a perforated nonwoven fabric, the area ratio (occupancy) between the adhesive portion and the nonwoven fabric portion (portion other than the adhesive portion) was 62% for the adhesive portion and 38% for the nonwoven fabric portion. It was.

(Example 3)
A monomer mixture in which 90 parts by weight of 2-ethylhexyl acrylate and 10 parts by weight of acrylic acid were mixed as a monomer component, a photopolymerization initiator [trade name “Irgacure 651” (manufactured by Ciba Japan)]: 0. 05 parts by weight, photopolymerization initiator [trade name “Irgacure 184” (manufactured by Ciba Japan)]: After blending 0.05 part by weight, viscosity (BH viscometer, No. 5 rotor, 10 rpm, measurement temperature: A composition (partially polymerized product, syrup) partially polymerized was produced by irradiating with ultraviolet rays until 30 ° C.) reached about 15 Pa · s. This syrup: 100 parts by weight, a photopolymerization initiator [trade name “Irgacure 651” (manufactured by Ciba Japan)]: 0.04 parts by weight, 1,6-hexanediol diacrylate: 0.1 parts by weight, interface Activator [trade name “Megafac F-477” manufactured by DIC Corporation]: 0.7 parts by weight, and carbon black: 0.02 parts by weight were added. Furthermore, a hollow glass balloon (trade name “Cell Star Z-27” manufactured by Tokai Kogyo Co., Ltd.) was added at a rate of 30% by volume with respect to the total volume of the syrup to prepare an adhesive precursor. In addition, the whole volume of the hollow glass balloon in an adhesive precursor is about 23 volume% with respect to the whole volume of this adhesive precursor. The pressure-sensitive adhesive precursor is opposed to a stator having a large number of fine teeth on a disk having a through-hole in the center and a stator having teeth, and fine teeth similar to the stator are formed on the disk. Nitrogen was introduced and air bubbles were mixed using an apparatus equipped with a rotor attached. The amount of bubbles mixed was introduced so as to be about 15% by volume with respect to the total volume of the discharged liquid material to obtain a bubble-containing pressure-sensitive adhesive composition.
A polyethylene terephthalate base material in which the bubble-containing pressure-sensitive adhesive composition is led to a wet-laminated roll coater with a tube (diameter: 19 mm, length: about 1.5 m), and two surfaces are peeled. The bubble-containing pressure-sensitive adhesive composition was applied between the release-treated surfaces so that the thickness after drying and curing was 1.2 mm. That is, the bubble-containing pressure-sensitive adhesive composition is sandwiched between polyethylene terephthalate substrates.
Next, ultraviolet rays having an illuminance of 5 mW / cm ² are irradiated from both sides for 4 minutes to cure the bubble-containing pressure-sensitive adhesive composition, thereby producing a pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer (bubble-containing pressure-sensitive adhesive layer). did.
The polymer polymerization rate of the obtained tape was 98.9% by weight.
A bubble-containing pressure-sensitive adhesive in which a hole-shaped nonwoven fabric of (porous screen use example 3) is bonded to one pressure-sensitive adhesive surface of the pressure-sensitive adhesive tape using a four-axis laminator, and one pressure-sensitive adhesive surface is covered with a hole-shaped nonwoven fabric. An adhesive tape having an agent layer was obtained. On the surface of the bubble-containing pressure-sensitive adhesive layer having a perforated nonwoven fabric, the area ratio (occupancy) between the adhesive portion and the nonwoven fabric portion (portion other than the adhesive portion) was 8% for the adhesive portion and 92% for the nonwoven fabric portion. It was.

(Comparative Example 1)
A monomer mixture in which 90 parts by weight of 2-ethylhexyl acrylate and 10 parts by weight of acrylic acid were mixed as a monomer component, a photopolymerization initiator [trade name “Irgacure 651” (manufactured by Ciba Japan)]: 0. 05 parts by weight, photopolymerization initiator [trade name “Irgacure 184” (manufactured by Ciba Japan)]: After blending 0.05 part by weight, viscosity (BH viscometer, No. 5 rotor, 10 rpm, measurement temperature: A composition (partially polymerized product, syrup) partially polymerized was produced by irradiating with ultraviolet rays until 30 ° C.) reached about 15 Pa · s. This syrup: 100 parts by weight, a photopolymerization initiator [trade name “Irgacure 651” (manufactured by Ciba Japan)]: 0.04 parts by weight, 1,6-hexanediol diacrylate: 0.1 parts by weight, interface Activator [trade name “Megafac F-477” manufactured by DIC Corporation]: 0.7 parts by weight, and carbon black: 0.02 parts by weight were added. Furthermore, a hollow glass balloon (trade name “Cell Star Z-27” manufactured by Tokai Kogyo Co., Ltd.) was added at a rate of 30% by volume with respect to the total volume of the syrup to prepare an adhesive precursor. In addition, the whole volume of the hollow glass balloon in an adhesive precursor is about 23 volume% with respect to the whole volume of this adhesive precursor. The pressure-sensitive adhesive precursor is opposed to a stator having a large number of fine teeth on a disk having a through-hole in the center and a stator having teeth, and fine teeth similar to the stator are formed on the disk. Nitrogen was introduced and air bubbles were mixed using an apparatus equipped with a rotor attached. The amount of bubbles mixed was introduced so as to be about 15% by volume with respect to the total volume of the discharged liquid material to obtain a bubble-containing pressure-sensitive adhesive composition.
A polyethylene terephthalate base material in which the bubble-containing pressure-sensitive adhesive composition is led to a wet-laminated roll coater with a tube (diameter: 19 mm, length: about 1.5 m), and two surfaces are peeled. The bubble-containing pressure-sensitive adhesive composition was applied between the release-treated surfaces so that the thickness after drying and curing was 1.2 mm. That is, the bubble-containing pressure-sensitive adhesive composition is sandwiched between polyethylene terephthalate substrates.
Next, ultraviolet rays having an illuminance of 5 mW / cm ² are irradiated from both sides for 4 minutes to cure the bubble-containing pressure-sensitive adhesive composition, thereby producing a pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer (bubble-containing pressure-sensitive adhesive layer). did.
The polymer polymerization rate of the obtained tape was 98.9% by weight.

(Evaluation)
About an Example and a comparative example, adhesive force, frictional force, and construction property were measured or evaluated, respectively.

(Measurement of adhesive strength)
Under the conditions of 23 ° C. and 50% RH, a pressure sensitive adhesive sheet having a width of 20 mm was reciprocated once with a 2 kg roller, followed by being stuck for 30 minutes. Thereafter, 180 ° peel peel force (N / 20 mm) from the adherend was measured (tensile speed: 300 mm / min) using a tensile tester (device name “TG-1kN” manufactured by Minebea).
Examples of the adherend include an aluminum plate (trade name “SK-A aluminum plate 1050P” manufactured by Sumitomo Light Metal Co., Ltd.), a polyethylene terephthalate (PET) film (trade name “S10 # 100” manufactured by Toray Industries, Inc.), and a glass plate (trade name). “Micro slide glass product number 5” manufactured by Matsunami Glass Industrial Co., Ltd., thickness: 3 mm) was used.

(Measurement of frictional force)
The adhesive tape sample cut into 2 cm × 2 cm was left on the adherend so that the porous screen surface (network surface) was in contact with the adherend. An aluminum plate (trade name “SK-A aluminum plate 1050P” manufactured by Sumitomo Light Metal Co., Ltd.) was used as the adherend.
Next, a 30-g weight was put on the stationary adhesive tape sample, and a 30-g load was fixed to the tape sample.
This adhesive tape sample was pulled in the horizontal direction at a speed of 300 mm / min, and the stress (N / cm ² ) applied at that time was measured.

(Evaluation of workability)
A pressure-sensitive adhesive tape sample (100 × 30 mm) was pressure-bonded so as to sandwich the end of an acrylic plate (100 mm × 100 mm, thickness: 2 mm). At that time, the porous screen surface (mesh surface) is directed outward (exposed). In this way, a sample for evaluation was produced.
Next, the sample for evaluation was inserted into a U-shaped aluminum frame (aluminum frame 33 in FIG. 4) in the direction a shown in FIG. 4, and the slipperiness at that time was evaluated according to the following evaluation criteria.
Evaluation criteria Good (◯): Good slippery and can be easily incorporated Bad (x): Poor slippery and difficult to incorporate.

  In addition, in a solar cell module, when using a foam tape as a sealing material between a panel end surface and a frame, it is preferable that the slipperiness at the time of incorporating a frame is favorable.

  FIG. 4 is a schematic cross-sectional view illustrating a method for evaluating workability. In FIG. 4, 41 is a double-sided adhesive tape sample, 42 is an acrylic plate, 43 is an aluminum frame, and a is the insertion direction. In Examples and Comparative Examples, workability was evaluated by the method shown in FIG.

FIG. 1 is a schematic top view of a bubble-containing acrylic pressure-sensitive adhesive layer having a porous screen on one pressure-sensitive adhesive surface. FIG. 2 is a schematic cross-sectional view of the AA cross section in the bubble-containing acrylic pressure-sensitive adhesive layer having a porous screen on one pressure-sensitive adhesive surface of FIG. FIG. 3 is a schematic cross-sectional view of a state in which a bubble-containing acrylic adhesive layer having a porous screen on one adhesive surface is in contact with a contact object in a non-pressurized state on the surface provided with the porous screen (3-1). ), And a schematic cross-sectional view (3-2) of a state in which the bubble-containing acrylic pressure-sensitive adhesive layer having a porous screen on one adhesive surface is in contact with a contact object in a pressurized state on the surface provided with the porous screen. is there. FIG. 4 is a schematic cross-sectional view illustrating a method for evaluating workability.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Bubble-containing acrylic adhesive layer 2 Porous screen 3 Contact thing 41 Double-sided adhesive tape 42 Acrylic board 43 Aluminum frame a Insertion direction

Claims (5)

A double-sided adhesive tape having a A acrylic-based pressure-sensitive adhesive layer,
The acrylic pressure-sensitive adhesive layer is an acrylic pressure-sensitive adhesive layer containing bubbles, or an acrylic pressure-sensitive adhesive layer containing bubbles and hollow microspheres,
The amount of bubbles is 5 to 50% by volume with respect to the total volume of the acrylic pressure-sensitive adhesive layer,
In at least one surface of the acrylic pressure-sensitive adhesive layer, a sample of 2 cm × 2 cm with a fixed load of 30g, and placed on an aluminum plate, pulled at a rate of 300 mm / min in the horizontal direction is defined as the stress at that time that frictional force, Ri 0.01~1.0N / cm ² der,
A double-sided adhesive tape characterized by being used for a solar cell module . Has a porous screen at least one surface of A acrylic-based pressure-sensitive adhesive layer,
The acrylic pressure-sensitive adhesive layer is an acrylic pressure-sensitive adhesive layer containing bubbles, or an acrylic pressure-sensitive adhesive layer containing bubbles and hollow microspheres,
The amount of bubbles is 5 to 50% by volume with respect to the total volume of the acrylic pressure-sensitive adhesive layer,
A 2 cm × 2 cm sample with a fixed load of 30 g is placed on an aluminum plate on the surface of the porous screen and pulled at a speed of 300 mm / min in the horizontal direction. 01~1.0N / cm ² der is,
The double-sided pressure-sensitive adhesive tape according to claim 1, wherein the double-sided pressure-sensitive adhesive tape is used for a solar cell module . In the surface having the porous screen of the acrylic pressure-sensitive adhesive layer, the area ratio between the adhesive portion and the porous screen portion (portion other than the adhesive portion) is 5 / The double-sided pressure-sensitive adhesive tape according to claim 2, which is 95 to 95/5. The double-sided pressure-sensitive adhesive tape according to any one of claims 1 to 3, wherein the amount of the hollow microspheres used in the acrylic pressure-sensitive adhesive layer containing the bubbles and the hollow microspheres is 5 to 40% by volume. The acrylic pressure-sensitive adhesive layer contains an acrylic polymer in which a (meth) acrylic acid alkyl ester and a polar group-containing monomer are used as monomer components constituting the acrylic pressure-sensitive adhesive layer. Double-sided adhesive tape as described.

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