JP4900897B2 - Adhesive tape and method for producing the same - Google Patents

Description

  The present invention relates to adhesive tapes. More specifically, the present invention relates to adhesive tapes having high gloss and excellent design. Moreover, this invention relates to the manufacturing method of adhesive tapes. More specifically, the present invention relates to a method for producing pressure-sensitive adhesive tapes having high gloss and excellent design.

  The pressure-sensitive adhesive tapes of the present invention are particularly useful for, for example, a coating substitute member excellent in design, which is particularly required in the automobile industry and the housing and building materials industry, and a tape or film for decoration and labeling.

  In general, surface protection adhesive tapes, decorative adhesive tapes, and paint substitute tapes for automobiles and homes are required to have a relatively large application area and to have a design and stability in appearance. Until now, most of these adhesive tapes have used PVC films on the market. This PVC film is widely used in various construction, automobile, and residential components because of its excellent workability, heat resistance, flexibility, and solvent resistance. Many manufacturers tend to limit or eliminate the use of PVC due to concerns over the generation of dioxins. Therefore, in recent years, PVC has been replaced with polyolefin resin, and incineration gas at the time of combustion has been made non-polluting, but the polyolefin resin is poor in scratch resistance, weather resistance stability and solvent resistance due to its characteristics, Many films have a hard coating layer on the surface.

  Such a design tape or a design film needs to be designed with various surface glosses for the purpose of giving the same surface glossiness as that of glass and giving a decorative glossiness. In particular, in high gloss products having a large gloss value (reflection angle 60 °) that generally represents surface glossiness, a coating agent such as urethane or acrylic is applied to the surface of the film substrate so as to have a thickness of 10 to 30 μm. It was necessary. Moreover, in many cases, the coating layer laminated | stacked with a polyolefin film is inferior to adhesiveness, and the primer was required as an intermediate | middle layer. When producing such a high-gloss film, a stable coating process is required, and as hard coding requires a thick coating thickness, it is difficult to reproduce a certain glossiness of the product. Met. Such unstable products and products having a multi-step coating process are very difficult to prevent an increase in cost and a decrease in yield (for example, see Patent Documents 1 and 2).

  Furthermore, when producing a high gloss film, it is necessary to manufacture the coating surface of the resin film used as a base material with a smooth surface roughness in advance. When a polyolefin film is used, since the surface has such a smooth surface, irregularities are generated on the film surface by a slight scratch, and even when a hard coat layer is provided, the appearance of the product is often poor. For this reason, it has been found that when a high-gloss film is made, it takes a lot of labor and cost to prevent a decrease in yield during appearance inspection.

  In addition, the same glossy product can be obtained by the heat fusion technology (for example, see Patent Documents 3 to 5) of a designable film and an olefin resin, which is generally used in recent years for injection molding, It has been found that it is necessary to have a mold having a prescribed shape, and the shape and time flexibility are poor. For this reason, there is a demand for pressure-sensitive adhesive tapes that are wide and easy in shape design, and have high glossiness that is excellent in production cost and time efficiency.

JP 2003-225977 A JP 2001-72945 A Japanese Patent Laid-Open No. 10-249886 Japanese Patent Laid-Open No. 11-207899 Japanese Patent Laid-Open No. 2003-71961

  Therefore, an object of the present invention is to provide a high gloss gloss design, and to have a curved surface followability, solvent resistance, scratch resistance, and weather resistance stability in order to solve the problems in conventional adhesive tapes. To provide a kind.

  Furthermore, the objective of this invention is providing the manufacturing method of the adhesive tapes which manufacture easily the adhesive tapes which have the said characteristic.

  In order to achieve the above object, the present inventors have intensively studied the physical properties of mainly adhesive tapes, and as a result, by using adhesive tapes having the following configuration, it has a high gloss design. The present inventors have found that an adhesive tape excellent in curved surface followability, solvent resistance, scratch resistance, and weather resistance stability can be obtained, and the present invention has been completed.

  That is, the pressure-sensitive adhesive tapes of the present invention are pressure-sensitive adhesive tapes having a pressure-sensitive adhesive layer formed on one surface of a resin film, and the surface roughness Ra is 0.5 μm or less on the other surface of the resin film. The smooth film which is is provided through the binder layer, It is characterized by the above-mentioned.

  In addition, the method for producing the adhesive tape of the present invention includes a step of forming an adhesive layer on one side of the resin film in the method for producing an adhesive tape, and a surface roughness Ra on the other side of the resin film. Including a step of bonding a smooth film having a thickness of 0.5 μm or less via a binder layer.

  In addition, surface roughness Ra in this invention means the value (micrometer) calculated as an average value of an absolute deviation value from an average line according to following formula (1), Complies with JIS B0601 (1994). Means what was requested.

なお、上記式（１）中、ｌは基準長さ、ｆ（ｘ）は粗さ曲線を表す関数を示すものとする。

In the above formula (1), l represents a reference length and f (x) represents a function representing a roughness curve.

  Moreover, the smooth film in this invention means the film whose surface roughness Ra is 0.5 micrometer or less.

  According to the present invention, as shown in the results of the examples, the adhesive layer formed on one side of the resin film described above is provided, and the surface roughness Ra is 0.5 μm or less on the other side of the resin film. Such a pressure-sensitive adhesive tape provided with a smooth film through a binder layer has a high glossy design and is excellent in solvent resistance and weather resistance stability. Although the details of the reason why the above adhesive tapes exhibit such characteristics are not clear, by providing a smooth film through the binder layer to the resin film, the adhesive of the binder layer is familiar to the uneven portion of the resin film surface, When causing the wetting phenomenon, it is presumed that the uneven portion is filled, and the glossiness equivalent to the surface of the smooth film is obtained as the whole adhesive tape.

  In addition, in this invention, a binder layer consists of an adhesive which can be suitably filled in the uneven | corrugated site | part of the said resin film surface.

  In the present invention, tapes mean flat materials, and usually include those called sheets and films.

  In the above adhesive tapes, the thickness of the smooth film is preferably 3 to 25 μm. By having such a film thickness, it is possible to further ensure the phase followability and scratch resistance.

  Moreover, in said adhesive tapes, it is preferable that the thickness of the said binder layer is 1-200 micrometers. By having such a thickness, the binder layer can fill the unevenness on the surface of the resin film by a wetting phenomenon, and it can be prevented from peeling off or causing phase roughness.

  Furthermore, in said adhesive tapes, it is preferable that surface roughness Ra of the surface which touches the smooth film of the said resin film is 0.5-5.0 micrometers. By having such a surface roughness Ra, the glossiness of the binder layer (the gloss value at a contact angle of 60 ° is 40 or more) can be more reliably obtained.

  In the above adhesive tapes, the resin film and / or the smooth film preferably includes a thermosetting acrylic hard coating layer having a thickness of 1 to 20 μm on at least one surface. By further providing the hard coating layer on the pressure-sensitive adhesive tapes of the present invention, pressure-sensitive adhesive tapes having solvent resistance and weather resistance stability more effectively.

  On the other hand, the adhesive tape of the present invention preferably has a gloss value of 40 or more.

  In addition, the gloss value in this invention means the value (%) measured by 60 degree angle | corner reflectance, is calculated | required based on JISK5600-4-7, and uses it as a parameter | index of glossiness. .

  On the other hand, the method for producing pressure-sensitive adhesive tapes of the present invention includes a step of forming a pressure-sensitive adhesive layer on one side of a resin film, and a smooth surface having a surface roughness Ra of 0.5 μm or less on the other side of the resin film. A step of bonding the film through a binder layer. By using such a production method, it is possible to easily produce pressure-sensitive adhesive tapes having the above-described effects.

  Hereinafter, embodiments of the present invention will be described in detail.

  The pressure-sensitive adhesive tapes of the present invention are pressure-sensitive adhesive tapes provided with a pressure-sensitive adhesive layer formed on one side of a resin film, and the surface roughness Ra is 0.5 μm or less on the other side of the resin film. A smooth film is provided through a binder layer.

  Since this invention has the significance as an alternative use of a soft PVC (polyvinyl chloride) film, the resin film used for this invention is a resin film which has other flexibility other than PVC.

  The resin film used in the present invention refers to a film obtained by melt extrusion molding or calendering, particularly containing a thermoplastic resin and an incompatible resin therein. Among these, a resin film having a layer containing a flexible polyolefin resin is preferable.

  As the thermoplastic resin, for example, a polyolefin resin such as polypropylene, polyethylene, or TPO resin (olefin-based thermoplastic elastomer) can be used. These resins may be used alone or in combination of two or more.

  Specific examples of the resin component constituting the resin film include, for example, low-density to high-density polyethylene, isotactic polypropylene, atactic polypropylene, syndiotactic polypropylene, polyester resin, polyamide resin, polycarbonate resin, A (meth) acrylic polymer or the like can be used. These resin components may be used alone or in combination of two or more.

  The (meth) acrylic polymer in the present invention refers to an acrylic polymer and / or a methacrylic polymer, and (meth) acrylate refers to an acrylate and / or methacrylate.

  Moreover, you may add arbitrarily ultraviolet absorbers and heat stabilizers, such as a benzotriazole type compound, a benzophenone type compound, a benzoate type compound, and a cyanoacrylate type compound, to a resin film, for example. These compounds may be used alone or in combination of two or more.

  The thickness of the resin film of the present invention may be appropriately set depending on the application, but is preferably 60 to 200 μm, and more preferably 75 to 150 μm.

  In the present invention, the surface roughness Ra of at least one surface of the resin film is preferably 0.5 to 5.0 μm, the surface roughness Ra is more preferably 0.5 to 2.0 μm, and the surface roughness More preferably, the thickness Ra is 0.5 to 1.5 μm. Generally, in order to increase the glossiness of a film, it is characterized in that the surface roughness Ra of the film surface serving as a base material is adjusted in advance to be less than 0.5 μm, and a coating agent of 10 to 30 μm is applied thereto. However, in the pressure-sensitive adhesive sheets of the present invention, even if a resin film having a surface roughness Ra of 0.5 μm or more is used without passing through the process of setting the surface roughness Ra to less than 0.5 μm, the glossiness can be easily increased. A film can be obtained. When the surface roughness Ra exceeds 5.0 μm, the gloss value (60 ° angle measurement) may not be 40 or more.

  A coloring agent, a filler, etc. can be added to the said resin film as needed.

  Examples of the colorant include known organic and inorganic pigments. Specific examples include organic pigments such as azo, phthalocyanine, selenium, quinacridone, and dioxazine, and inorganic pigments such as carbon black, calcium carbonate, and titanium oxide. These colorants may be used alone or in admixture of two or more. Moreover, the compounding quantity of the coloring agent of the said coloring agent is 1-40 weight part normally with respect to 100 weight part of resin components.

  Examples of the filler include inorganic fillers such as talc, titanium oxide, calcium carbonate, clay, mica, barium sulfate, whiskers, and magnesium hydroxide. These fillers may be used alone or in combination of two or more. The filler preferably has an average particle size of 0.1 to 10 μm. Further, the content of the filler is not particularly specified, but is usually 1 to 200 parts by weight with respect to 100 parts by weight of the resin in the base material layer.

  In addition to the above components, the resin film further includes various tackifiers such as phenol resin, terpene-phenol resin, terpene resin, xylene resin, rosin, hydrogenated rosin, lubricant, anti-aging agent, surfactant. , Plasticizer, antifoaming agent, flame retardant, light stabilizer, thixotropic agent, UV absorber, low molecular weight polymer, surface lubricant, leveling agent, antioxidant, polymerization inhibitor, heat stabilizer, hydrolysis resistance Agents, metal powders, particles, foils, etc. can be used as appropriate. These components may be used alone or in combination of two or more.

  In addition, various discharge treatments, anchor coating treatments, and the like may be applied to the surface of the base material for the purpose of improving the adhesiveness with the pressure-sensitive adhesive layer or the binder layer.

  As the smooth film in the present invention, various films may be used as long as the surface roughness Ra is 0.5 or less. For example, a biaxially stretched film such as a polyethylene terephthalate film or a polybutylene terephthalate film, a polyolefin-based or polycarbonate-based unstretched film, or the like can be used. Moreover, if various thermoplastic resin surfaces are manufactured smoothly so that the surface roughness Ra is 0.5 or less, these films can also be used as a smooth film.

  The smooth film has a surface roughness Ra of 0.5 or less. From the viewpoint of glossiness, the surface texture Ra is preferably 0.3 μm or less, and more preferably 0.2 μm or less.

  The thickness of the smooth film is preferably 3 to 25 μm, more preferably 3 to 15 μm, and even more preferably 3 to 10 μm from the viewpoint of flexibility and curved surface followability. When the thickness of the smooth film exceeds 25 μm, the phase followability and rumination resistance may be inferior. On the other hand, when the thickness is smaller than 3 μm, the scratch resistance may be inferior.

  In addition to the above-mentioned components, the smooth film may further include various tackifiers such as phenol resin, terpene-phenol resin, terpene resin, xylene resin, rosin and hydrogenated rosin, and inorganic such as calcium carbonate and carbon black. Fillers, lubricants, anti-aging agents, dyes, colorants, pigments, surfactants, plasticizers, antifoaming agents, flame retardants, light stabilizers, thixotropic agents, UV absorbers, low molecular weight polymers, surface lubricants, Leveling agents, antioxidants, polymerization inhibitors, heat stabilizers, hydrolysis stabilizers, metal powders, particles, foils, and the like can be used as appropriate. These components may be used alone or in combination of two or more.

  In the present invention, a thermosetting acrylic hard coating layer can be formed on at least one surface of the resin film and / or smooth film. By providing the hard coating layer, weather resistance stability, light stability, and solvent resistance can be improved.

  For the hard coating layer, for example, a Hals hybrid polymer obtained by copolymerizing a functional group having a hindered amine light stabilizer (HALS) with a polymer having an acrylic skeleton is preferably used.

  The Hals hybrid polymer having an acrylic skeleton is an acrylic polymer obtained by copolymerizing a hindered amine light stabilizer (HALS) having a (meth) acrylate skeleton and a functional group at the terminal. Examples of the (meth) acrylate include alkyl (meth) acrylate (as the alkyl group, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, 2-ethylhexyl group, lauryl group, And a monomer having a crosslinkable functional group, for example, a monomer having a hydroxyl group, a carboxyl group, a methylol group, an acid anhydride group, an amino group, an epoxy group, or the like. These compounds may be used alone or in combination of two or more.

  HALS can be used without any particular limitation. Specifically, for example, reaction types such as ADK STAB LA-82 and LA-87 manufactured by Asahi Denka Co., Ltd., Hostabin N-20 manufactured by Hoechst Japan, Yoshitomi Fine Chemical Monomer type such as Tomi Soap 77 manufactured by the company, and oligomer type such as Uvinal 5050H manufactured by BASF Japan. These compounds may be used alone or in combination of two or more.

  The hard coating layer in the present invention has a hydroxyl value (varnish value) indicating the amount of crosslinking points of 20 to 80, preferably among hard coating agents of a Hals hybrid polymer having an acrylic skeleton having weather resistance and light stability. Is a high-density cross-linking type 30-70, more preferably 40-60. When the hydroxyl value (varnish value) is less than 20, the solvent resistance is remarkably lowered. When it exceeds 80, the solvent resistance is excellent, but the flexibility tends to be poor.

  The hard coating layer in the present invention is generally laminated on the resin film and / or smooth film as a polymer solution, but the thickness is usually 1 to 10 μm, preferably 1.5 to 8 μm, It is more preferable that it is 2-5 micrometers. The thickness is desirable in that the solvent resistance is effectively expressed and at the same time the flexibility is maintained. If it is smaller than 1 μm, the solvent resistance is poor, and if it is larger than 10 μm, the flexibility may be poor.

  Examples of the solvent used in the polymer solution include aromatic hydrocarbon solvents such as toluene and xylene, aliphatic carboxylic acid ester solvents such as ethyl acetate and butyl acetate, and aliphatic hydrocarbons such as hexane, heptane and octane. Examples thereof include ketone solvents such as acetone solvents, acetone, methyl ethyl ketone, and methyl isobutyl ketone. These solvents may be used alone or in combination of two or more.

  Further, the content of the solvent in the polymer solution is usually about 10 to 70% by weight.

  In addition to the above-described components, the polymer solution may further include various tackifiers such as phenol resin, terpene-phenol resin, terpene resin, xylene resin, rosin, hydrogenated rosin, and inorganic such as calcium carbonate and carbon black. Fillers, lubricants, anti-aging agents, dyes, colorants, pigments, surfactants, plasticizers, antifoaming agents, flame retardants, light stabilizers, thixotropic agents, UV absorbers, low molecular weight polymers, surface lubricants, Leveling agents, antioxidants, polymerization inhibitors, heat stabilizers, hydrolysis stabilizers, metal powders, particles, foils, and the like can be used as appropriate. These components may be used individually by 1 type, or may use 2 or more types.

  The method for applying the polymer solution is not particularly limited, and a commonly used method can be appropriately used. For example, the polymer solution can be applied onto the resin film by appropriately using a coating machine such as a bar coater, a spin coater, a roll coater, or an applicator.

  The pressure-sensitive adhesive tapes of the present invention are obtained by bonding a smooth film to the above resin film via a binder layer.

  In addition, in this invention, a binder layer consists of an adhesive which can be suitably filled in the uneven | corrugated site | part of the said resin film surface.

  The method for coating the binder layer is not particularly limited, and a commonly used method can be appropriately used. For example, a binder layer can be formed by applying an adhesive solution on the resin film (or smooth film, separator) using the coating machine and removing the solvent. In addition, a binder may be formed by adding a crosslinking agent to the adhesive solution and curing the adhesive polymer by heating and crosslinking.

  As the pressure-sensitive adhesive, known ones can be used without particular limitation. For example, various pressure-sensitive adhesives such as a rubber-based pressure-sensitive adhesive, an acrylic pressure-sensitive adhesive, and a silicone-based pressure-sensitive adhesive can be used. These pressure-sensitive adhesives may be used alone or in combination of two or more.

  As the crosslinking agent used in the binder layer, an isocyanate compound, an epoxy compound, a melamine resin, an aziridine derivative, a metal chelate compound, or the like is used. Among these, an isocyanate compound and an epoxy compound are particularly preferably used mainly from the viewpoint of obtaining an appropriate cohesive force. In particular, in the production of a polymer, a hydroxyl group is introduced into the polymer by copolymerizing a hydroxyl group-containing monomer such as 2-hydroxyethyl acrylate, and a polyisocyanate compound is used as a crosslinking agent for the polymer. preferable. These crosslinking agents may be used alone or in combination of two or more.

  Examples of the isocyanate compound include lower aliphatic polyisocyanates such as butylene diisocyanate and hexamethylene diisocyanate, alicyclic isocyanates such as cyclopentylene diisocyanate, cyclohexylene diisocyanate, and isophorone diisocyanate, 2,4-tolylene diisocyanate, Aromatic isocyanates such as 4,4′-diphenylmethane diisocyanate and xylylene diisocyanate, trimethylolpropane / tolylene diisocyanate trimer adduct (trade name Coronate L, manufactured by Nippon Polyurethane Industry Co., Ltd.), trimethylolpropane / hexamethylene Diisocyanate trimer adduct (trade name Coronate HL, manufactured by Nippon Polyurethane Industry Co., Ltd.), isocyanurate of hexamethylene diisocyanate Body (trade name: Coronate HX, manufactured by Nippon Polyurethane Industry Co., Ltd.) isocyanate adducts such as, such as diisocyanate adduct of the polyol, and the like. These compounds may be used alone or in combination of two or more.

  Examples of the epoxy compound include N, N, N ′, N′-tetraglycidyl-m-xylenediamine (trade name: TETRAD-X, manufactured by Mitsubishi Gas Chemical Company) and 1,3-bis (N, N-diglycidyl). Aminomethyl) cyclohexane (trade name: TETRAD-C, manufactured by Mitsubishi Gas Chemical Company, Inc.). These compounds may be used alone or in combination of two or more.

  Examples of the melamine-based resin include hexamethylol melamine.

  Examples of the aziridine derivative include commercially available product name HDU, product name TAZM, product name TAZO (all of which are manufactured by Mutual Pharmaceutical Co., Ltd.) and the like. These compounds may be used alone or in combination of two or more.

  Examples of the metal chelate compound include aluminum, iron, tin, titanium, and nickel as metal components, and acetylene, methyl acetoacetate, and ethyl lactate as chelate components. These compounds may be used alone or in combination of two or more.

  Content of the crosslinking agent used for a binder layer is about 0.01-5 weight part normally with respect to 100 weight part of base polymers, such as a (meth) acrylic-type polymer.

  Moreover, the solvent arbitrarily used for application | coating of a binder layer can be especially used without a restriction | limiting. For example, aromatic hydrocarbon solvents such as toluene, xylene and mesitylene, aliphatic carboxylic acid solvents such as ethyl acetate and butyl acetate, aliphatic hydrocarbon solvents such as hexane, heptane and octane, acetone, methyl ethyl ketone and methyl Examples thereof include ketone solvents such as isobutyl ketone. These solvents may be used alone or in combination of two or more.

  In addition to the above components, the binder layer may further include various tackifiers such as phenol resin, terpene-phenol resin, terpene resin, xylene resin, rosin, and hydrogenated rosin, and inorganic such as calcium carbonate and carbon black. Fillers, lubricants, anti-aging agents, dyes, colorants, pigments, surfactants, plasticizers, antifoaming agents, flame retardants, light stabilizers, thixotropic agents, UV absorbers, low molecular weight polymers, surface lubricants, Leveling agents, antioxidants, polymerization inhibitors, heat stabilizers, hydrolysis stabilizers, metal powders, particles, foils, and the like can be used as appropriate. These arbitrary components may be used individually by 1 type, or may use 2 or more types.

  The thickness of the binder layer used in the present invention is preferably about 1 to 200 μm after drying, more preferably 3 to 30 μm, and more preferably 3 to 20 μm. If it is smaller than 1 μm, the adhesive strength to the adherend becomes insufficient, and it may be difficult to fill the uneven portions on the surface of the resin film. On the other hand, if it exceeds 200 μm, the adhesive strength is saturated and is not economical. Protruding or causing cohesive failure, making it difficult to peel off.

  The method for forming the binder layer on the resin film is not particularly limited. For example, the binder layer is applied to a separator (or a resin film or a smooth film), and the polymerization solvent is removed by drying to remove the binder layer from the separator (or resin). Film or smooth film), or by applying the pressure-sensitive adhesive on another substrate, drying and removing the polymerization solvent, etc., and transferring the binder layer to a separator (or resin film, smooth film). It is produced by the method to do. Further, after the binder layer is formed, curing may be performed for the purpose of adjusting the component transfer of the binder layer or adjusting the crosslinking reaction. In addition, when an adhesive is applied on a separator (or resin film, smooth film) or the like to produce an adhesive sheet, the composition can be applied uniformly on the separator (or resin film, smooth film) or the like. One or more solvents other than the polymerization solvent may be newly added to the product.

  Moreover, as a formation method of the said binder layer, the well-known method used for manufacture of adhesive sheets is used suitably. Specifically, for example, methods such as roll coat, kiss roll coat, gravure coat, reverse coat, roll brush, spray coat, dip roll coat, bar coat, knife coat, air knife coat, extrusion coat method using a die coater, etc. Can be given.

  The pressure-sensitive adhesive tapes of the present invention are formed by coating a pressure-sensitive adhesive on the resin film (on one of the hard coating layers if a hard coating layer is provided on both sides of the resin film) to form a pressure-sensitive adhesive layer. It is.

  The method for applying the pressure-sensitive adhesive is not particularly limited, and a commonly used method can be appropriately used. For example, the pressure-sensitive adhesive layer can be formed by applying the pressure-sensitive adhesive solution onto a resin film (or separator) using the coating machine and removing the solvent. Alternatively, a pressure-sensitive adhesive layer can be formed by adding a cross-linking agent to the pressure-sensitive adhesive solution and curing by heating to cure the pressure-sensitive adhesive polymer.

  The pressure-sensitive adhesive can be used without particular limitation. For example, various pressure-sensitive adhesives such as a rubber-based pressure-sensitive adhesive, an acrylic pressure-sensitive adhesive, and a silicone-based pressure-sensitive adhesive can be used. These pressure-sensitive adhesives may be used alone or in combination of two or more.

  As the crosslinking agent used for the pressure-sensitive adhesive, an isocyanate compound, an epoxy compound, a melamine resin, an aziridine derivative, a metal chelate compound, or the like is used. Among these, an isocyanate compound and an epoxy compound are particularly preferably used mainly from the viewpoint of obtaining an appropriate cohesive force. In particular, in the production of a polymer, a hydroxyl group is introduced into the polymer by copolymerizing a hydroxyl group-containing monomer such as 2-hydroxyethyl acrylate, and a polyisocyanate compound is used as a crosslinking agent for the polymer. preferable. These compounds may be used alone or in combination of two or more.

  Examples of the isocyanate compound include lower aliphatic polyisocyanates such as butylene diisocyanate and hexamethylene diisocyanate, alicyclic isocyanates such as cyclopentylene diisocyanate, cyclohexylene diisocyanate, and isophorone diisocyanate, 2,4-tolylene diisocyanate, Aromatic isocyanates such as 4,4′-diphenylmethane diisocyanate and xylylene diisocyanate, trimethylolpropane / tolylene diisocyanate trimer adduct (trade name Coronate L, manufactured by Nippon Polyurethane Industry Co., Ltd.), trimethylolpropane / hexamethylene Diisocyanate trimer adduct (trade name Coronate HL, manufactured by Nippon Polyurethane Industry Co., Ltd.), isocyanurate of hexamethylene diisocyanate Body (trade name: Coronate HX, manufactured by Nippon Polyurethane Industry Co., Ltd.) isocyanate adducts such as, such as diisocyanate adduct of the polyol, and the like. These compounds may be used alone or in combination of two or more.

  Examples of the epoxy compound include N, N, N ′, N′-tetraglycidyl-m-xylenediamine (trade name: TETRAD-X, manufactured by Mitsubishi Gas Chemical Company) and 1,3-bis (N, N-diglycidyl). Aminomethyl) cyclohexane (trade name: TETRAD-C, manufactured by Mitsubishi Gas Chemical Company, Inc.). These compounds may be used alone or in combination of two or more.

  Examples of the melamine-based resin include hexamethylol melamine.

  Examples of the aziridine derivative include commercially available product name HDU, product name TAZM, product name TAZO (all of which are manufactured by Mutual Pharmaceutical Co., Ltd.) and the like. These compounds may be used alone or in combination of two or more.

  Examples of the metal chelate compound include aluminum, iron, tin, titanium, and nickel as metal components, and acetylene, methyl acetoacetate, and ethyl lactate as chelate components. These compounds may be used alone or in combination of two or more.

  The content of the crosslinking agent used in the pressure-sensitive adhesive is usually about 0.01 to 5 parts by weight with respect to 100 parts by weight of the base polymer such as a (meth) acrylic polymer.

  Moreover, the solvent arbitrarily used for application | coating of an adhesive can use a well-known thing without a restriction | limiting especially. For example, aromatic hydrocarbon solvents such as toluene, xylene and mesitylene, aliphatic carboxylic acid solvents such as ethyl acetate and butyl acetate, aliphatic hydrocarbon solvents such as hexane, heptane and octane, acetone, methyl ethyl ketone and methyl Examples thereof include ketone solvents such as isobutyl ketone. These solvents may be used alone or in combination of two or more.

  In addition to the above-mentioned components, the pressure-sensitive adhesive further includes various tackifiers such as phenol resin, terpene-phenol resin, terpene resin, xylene resin, rosin and hydrogenated rosin, and inorganic such as calcium carbonate and carbon black. Fillers, lubricants, anti-aging agents, dyes, colorants, pigments, surfactants, plasticizers, antifoaming agents, flame retardants, light stabilizers, thixotropic agents, UV absorbers, low molecular weight polymers, surface lubricants, Leveling agents, antioxidants, polymerization inhibitors, heat stabilizers, hydrolysis stabilizers, metal powders, particles, foils, and the like can be used as appropriate. These arbitrary components may be used individually by 1 type, or may use 2 or more types.

  The thickness of the pressure-sensitive adhesive layer used in the present invention is preferably about 1 μm to 300 μm after drying, and more preferably 10 μm to 75 μm. When the thickness is less than 1 μm, the adhesive strength to the adherend becomes insufficient, and when the thickness exceeds 300 μm, the adhesive strength is saturated, which is not economical, and the adhesive sticks out or causes cohesive failure, and is difficult to peel off.

  The method for forming the pressure-sensitive adhesive layer on the resin film is not particularly limited. For example, the pressure-sensitive adhesive is applied to a separator (or resin film), and the polymerization solvent is removed by drying to remove the pressure-sensitive adhesive layer from the separator (or resin film). ) Or a method in which the pressure-sensitive adhesive is applied onto another substrate, the polymerization solvent is dried and removed, and the pressure-sensitive adhesive layer is transferred to a separator (or resin film). The Further, after the formation of the pressure-sensitive adhesive layer, curing may be performed for the purpose of adjusting the component transfer of the pressure-sensitive adhesive layer or adjusting the crosslinking reaction. In addition, when a pressure-sensitive adhesive is applied onto a separator (or resin film) or the like to produce pressure-sensitive adhesive sheets, other than the polymerization solvent in the composition so that it can be uniformly applied onto the separator (or resin film) or the like. One or more kinds of solvents may be newly added.

  Moreover, as a formation method of the said adhesive layer, the method used for manufacture of adhesive sheets is used suitably. Specifically, for example, methods such as roll coat, kiss roll coat, gravure coat, reverse coat, roll brush, spray coat, dip roll coat, bar coat, knife coat, air knife coat, extrusion coat method using a die coater, etc. Can be given.

  For the separator (or resin film), if necessary, for example, a silicone, fluorine, long chain alkyl or fatty acid amide release agent, release with a silica powder and antifouling treatment, acid treatment, etc. Further, it is possible to carry out an antistatic treatment such as an alkali treatment, a primer treatment, an anchor coat treatment, a corona treatment, a plasma treatment, an ultraviolet treatment, a coating type, a kneading type, or a vapor deposition type.

  The pressure-sensitive adhesive tapes of the present invention are formed by, for example, laminating a pressure-sensitive adhesive on a concavo-convex surface of a separator (release liner, release sheet) having a concavo-convex release form, and the concavo-convex shape is transferred to the pressure-sensitive adhesive layer to form a groove. A structure may be formed. The separator for forming the concavo-convex shape can be produced by processing into a desired concavo-convex shape by a known method. The concavo-convex shape formed on the separator is not particularly limited as long as the continuous groove structure can be transferred to the pressure-sensitive adhesive layer. For example, a plurality of continuous lattice structures such as the separator shown in FIG. It can be defined (convex width: (a), convex height (b), concave width: (c)).

  In particular, the adhesive tapes of the present invention can effectively use a separator having a recess width (c) of 400 μm or more and (a) + (c) of 450 μm or more. In the pressure-sensitive adhesive tapes of the present invention, the separator can be used without being particular about the pitch size and the pressure-sensitive adhesive composition, and (a) + (c) is preferably 400 to 700 μm, and 450 to 550 μm. Is more preferable.

  As the separator used in the present invention, those conventionally used as separators can be appropriately used without particular limitation. Specifically, as a constituent material of the separator (release sheet), for example, plastic films such as polyethylene, polypropylene, polyethylene terephthalate, and polyester film, paper products such as glassine paper, coated paper, and laminated paper, cloth, nonwoven fabric, etc. Examples thereof include a porous material, a net, a foam sheet, a metal foil, and appropriate thin leaves such as a laminate thereof, and a plastic film is preferably used from the viewpoint of excellent surface smoothness. The film is not particularly limited as long as it can protect the pressure-sensitive adhesive layer. For example, polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, polyvinyl chloride film, vinyl chloride copolymer. Examples thereof include a coalesced film, a polyethylene terephthalate film, a polybutylene terephthalate film, a polyurethane film, and an ethylene-vinyl acetate copolymer film.

  The concavo-convex shape is transferred to the pressure-sensitive adhesive layer by, for example, laminating a pressure-sensitive adhesive layer on the separator having the concavo-convex shape, or attaching the concavo-convex shape surface of the separator to the pressure-sensitive adhesive layer. Further, the recess depth (b) of the groove of the pressure-sensitive adhesive layer is 15 to 25 μm, the protrusion width (c) is 400 μm to 600 μm, and the recess width (a) is 30 to 70 μm. preferable.

  As the method for forming the concavo-convex shape, for example, a method in which an adhesive layer is formed on the concavo-convex surface of a separator having a concavo-convex release surface, and then the adhesive layer and a resin film are bonded together, or a resin film There is a method in which a pressure-sensitive adhesive layer is formed thereon and then a separator having an uneven shape is bonded to the pressure-sensitive adhesive layer. The uneven shape formed on the separator surface is transferred to the pressure-sensitive adhesive layer by these methods.

  The separator is usually removed as appropriate when the pressure-sensitive adhesive layer surface is used.

  The pressure-sensitive adhesive tapes of the present invention are excellent in that they can be used without being influenced by the width of the recess or the pressure-sensitive adhesive composition as described above.

  The pressure-sensitive adhesive tapes of the present invention have the above-described configuration, have high gloss design properties, and have excellent curved surface followability, solvent resistance, scratch resistance, and weather resistance stability. Therefore, for example, it is particularly useful for a coating substitute member excellent in design and particularly a tape or film for decoration and labeling, which is particularly required in the automobile industry and the housing and building materials industry.

  The method for producing the pressure-sensitive adhesive tape of the present invention includes a step of forming a pressure-sensitive adhesive layer on one side of the resin film, and a smooth surface having a surface roughness Ra of 0.5 μm or less on the other side of the resin film. A step of bonding the film through a binder layer.

  Generally, high glossiness of a film is obtained by adjusting the surface roughness of the film surface as a base material in advance so that Ra is less than 0.5 μm, and applying a coating agent of 10 to 30 μm here. Yes. Such a technique requires an operation step for setting the surface roughness of the film surface serving as a base material to a predetermined value or less, and since the coating layer is applied thickly, it is difficult to reproduce the constant glossiness of the product.

  On the other hand, in the pressure-sensitive adhesive sheets of the present invention, even if the surface roughness Ra of the resin film constituting the substrate is a rough surface of 0.5 to 5.0 μm, the surface roughness Ra is 0. 0 through the binder layer. By laminating a smooth film of 5 or less, the pressure-sensitive adhesive becomes familiar with the substrate uneven portion, and the uneven portion can be filled cleanly by causing a wetting phenomenon. Furthermore, the surface roughness Ra of the smooth film is very smooth, and even with a film having large irregularities, the glossiness and surface roughness equivalent to the smooth film surface can be easily obtained by simply bonding the smooth film through a binder layer. Can be obtained.

  The glossiness of the glossy film thus produced has a target gloss value that varies depending on the product to be used. In general, the surface roughness Ra of the film used for the base is 10 μm on the rough surface having a surface roughness Ra of about 5.0 μm. When it is applied to ˜30 μm, since the underlying film surface is too rough, it is very difficult to produce pressure-sensitive adhesive sheets having a gloss value measured at a 60 ° angle of 40 or higher. However, when the present invention is used, a gloss value of 40 or more (60) that easily indicates surface glossiness can be obtained by simply laminating a smooth film regardless of the surface roughness Ra of 0.5 to 5.0 μm. ° angle measurement) can be obtained.

  By using the method for producing the present adhesive tape, it is possible to design the shape of the adhesive tapes having the above-mentioned effects in a wide and easy manner, and to provide a high gloss design film excellent in production cost and time efficiency.

  Hereinafter, examples and the like specifically showing the configuration and effects of the present invention will be described, but the present invention is not limited to these. In addition, the evaluation item in an Example etc. measured as follows.

<Measurement of surface roughness>
Surface roughness Ra of the film obtained by the said Example and the comparative example is based on JISB0601 (1994), and is a stylus type surface roughness measuring machine (K-El Tencor company make, P-11, measurement length) Measured using 3 mm).

<Measurement of gross value>
As an index of glossiness, the gloss value of the 60 ° reflection angle rate of the films obtained in the above-mentioned examples and comparative examples is based on JIS K 5600-4-7, and microtrigloss (manufactured by Gardner) is used. It was measured.

<Evaluation of weather resistance stability>
The produced adhesive tape was irradiated with a metal halide lamp type acceleration tester (Daipla Corp., die plastic / metal weather tester) with a light irradiation degree of 900 W / m ² (BPT = 63 ° C.) for 4 hours, dark (BPT = 70 ° C.) A total of 12 hours of 4 hours and 4 hours of condensation was taken as one cycle, and a total of 80 cycles were carried out to obtain a sample for evaluation.

  Next, the color difference of the sample for evaluation was measured with a color difference meter (manufactured by Minolta, CR-400), and the colorability was evaluated using the sample for evaluation before and after the accelerated test treatment. The color difference calculation method and the gloss retention rate calculation method are as follows.

(Calculation method of color difference)
The color difference is a value represented by ΔE ^* ab,
Delta] E ^* ab = _{^{[(L * 2 -L * 1)}} 2 + (a * 2 -a * 1) 2 + (b * 2 -b * 1) 2 ] ^1/2
Calculated by Here, L ^* , a ^* , and b ^* are values defined in the CIE 1976 color system,
L ^* ₂ , a ^* ₂ , and b ^* ₂ are L ^* , a ^* , and b ^* of the evaluation samples after the accelerated test processing,
L ^* ₁ , a ^* ₁ , and b ^* ₁ are L ^* , a ^* , and b ^* of the sample for evaluation before the accelerated test process, respectively.

(Gloss retention rate calculation method)
The gloss value retention rate is (100− (G ₁ −G ₂ )) / G ₁ × when the gross value before test (test angle 60 °) G ₁ and the gross value after test (test angle 60 °) G ₂ are used. It calculated | required by calculating as 100 (%).

(Method for evaluating weather resistance stability)
The evaluation criteria for weather resistance stability are as follows.
When the color difference (ΔE ^* ab) is 2.0 or less and the gloss retention is 80% or more: ○
・ When the color difference (ΔE ^* ab) exceeds 2.0: ×
・ When gross retention is less than 80%: ×

<Evaluation of scratch resistance>
The scratch resistance of the films obtained in the above Examples and Comparative Examples was evaluated using a Taber abrasion tester (manufactured by Toyo Seiki Co., Ltd.).

Specifically, the surface condition after performing a scratching process (abrasion wheel: CF-10F, load: 5N, rotation speed: 60 rpm, 1000 rotation process) on each of the films was visually observed and evaluated. The evaluation criteria are as follows.
・ When there is no damage or damage to the resin film: ○
・ If the resin film is scratched or damaged: ×

<Evaluation of resilience resistance>
Cut the adhesive tape obtained in the above examples and comparative examples into a size of 3cm x 3cm, and paste the adhesive tape around the side of the melamine coated iron plate (length 7cm x width 15cm x thickness 0.9mm) The cut was made at a 2 mm portion in the plane direction from the apex of the side surface.

The state after leaving this pasting part with an adhesion area of 0.6 cm ² in an environment of 23 ° C. × 50% RH for 1 hour was visually observed and evaluated. The evaluation criteria are as follows.
・ If the entire surface is stuck: ○
・ If floating occurs on about half of the entire surface: △
・ When floating occurs on the entire surface: ×

<Evaluation of cracking>
The adhesive tapes obtained in the above Examples and Comparative Examples were bent at 180 ° with a radius of curvature R = 1 mm, and the presence or absence of cracks at that time was examined. The evaluation criteria are as follows.
・ If no cracks occurred: ○
・ If a crack occurs: ×

<Evaluation of solvent resistance>
After toluene was put into a screw tube bottle to make a meniscus state, only the surface of the hard coat layer of the plastic film coated with the hard coat layer was brought into contact with the solvent (toluene) to be in close contact with the solvent. The thickness of the base film before contact with the solvent and 5 minutes after the contact with the solvent was measured using a 1/1000 mm dial gauge, and the expansion coefficient (thickness variation rate) of the base film was calculated according to the following formula.
Base material expansion rate (%) = (“Base film thickness after contact (μm)” − “Base film thickness before contact (μm)”) / “Base film thickness before contact (μm)” × 100

Furthermore, the occurrence and change of surface shape appearance due to solvent contact of the hard coat layer were observed and evaluated. The evaluation criteria are as follows.
・ When there is no change on the film surface: ○
・ If small cracks or blisters occur on the film surface: ×

[Example 1]
Homo polypropylene resin (Homo-PP) (Nippon Polychem, FY4), linear low density polyethylene (LDPE) (Sumitomo Chemical, Sumikasen G-401), and r-TPO resin (reactor (polymerization type) olefin) Thermoplastic elastomer) (manufactured by Sun Allomer Co., Ltd., X500F) was extruded at a ratio of homo-PP: LDPE: r-TPO resin = 60 parts by weight: 20 parts by weight: 20 parts by weight (GM Engineering, GM30). -28 extruder), and molded into a melt-extruded sheet (thickness: 100 μm) from a T-die film forming apparatus (manufactured by GMM Engineering, T300T die) to obtain an olefin film as a resin film. Under the present circumstances, the cast roll was prepared so that resin film surface roughness Ra might be set to 1.04 micrometer.

  Next, a resin film with a binder layer (total thickness: 8 μm) provided with an acrylic pressure-sensitive adhesive (manufactured by Nitto Denko Corporation, thickness: 4 μm) on a PET (polyethylene terephthalate) film (thickness: 4 μm, Ra = 0.1 μm). As a hard coating layer, HALS copolymer Hals hybrid polymer (manufactured by Nippon Shokubai Co., Ltd., Hals Hybrid UV-G300, hydroxyl value (varnish value): 39 ± 8), 100 parts by weight, curing agent (manufactured by Sumitomo Biurethane Co., Sumijour) N-3200) 13 parts by weight and a diluting solvent (ethyl acetate) were mixed so that the non-volatile content was 20%, and then the mixture was applied using a bar coater so that the thickness after drying was 2 μm. Then, drying at 120 ° C. for 2 minutes, followed by curing aging (2 days at 60 ° C.) for smooth film with a binder layer Lum got. Then, using a lamination, a smooth film was bonded to the olefin film (surface with Ra of 1.04 μm) through a binder layer to obtain a resin film with a smooth film.

  Next, a pressure-sensitive adhesive polymer solution in which an acrylic pressure-sensitive adhesive (manufactured by Nitto Denko Corporation, 2-ethylhexyl acrylate pressure-sensitive adhesive) and a cross-linking agent (manufactured by Nippon Polyurethane Industry Co., Ltd., Coronate L) were mixed at a nonvolatile content of 20% by weight on the separator surface. (Acrylic adhesive: crosslinking agent = 100: 3) was applied using an applicator so that the thickness of the adhesive layer after drying was 30 μm. Then, the adhesive layer was formed by drying at 100 degreeC for 2 minutes, and the separator with an adhesive layer was produced. To the separator with the pressure-sensitive adhesive layer, the resin film side of the resin film with the smooth film was bonded with a laminator so as not to cause air bubbles and unevenness, thereby obtaining a pressure-sensitive adhesive tape.

[Example 2]
Instead of a smooth film (total thickness: 8 μm) with a binder layer provided on a PET (polyethylene terephthalate) film (thickness: 4 μm, Ra = 0.1 μm) with an acrylic adhesive (manufactured by Nitto Denko Corporation, thickness: 4 μm), Except for using a smooth film (total thickness: 17 μm) with a binder layer provided with an acrylic adhesive (manufactured by Nitto Denko Corporation, thickness: 13 μm) on a PET (polyethylene terephthalate) film (thickness: 4 μm, Ra = 0.1 μm). Produced an adhesive tape in the same manner as in Example 1.

Example 3
Instead of a smooth film (total thickness: 8 μm) with a binder layer provided on a PET (polyethylene terephthalate) film (thickness: 4 μm, Ra = 0.1 μm) with an acrylic adhesive (manufactured by Nitto Denko Corporation, thickness: 4 μm), A smooth film with a binder layer (total thickness: 36 μm) provided with an acrylic adhesive (manufactured by Nitto Denko Corporation, thickness: 24 μm) on a PET (polyethylene terephthalate) film (thickness: 12 μm, Ra = 0.1 μm) was used. Produced an adhesive tape in the same manner as in Example 1.

[Comparative Example 1]
On the olefin film (surface with Ra of 1.04 μm), which is the resin film obtained in Example 1, as a hard coating layer, HALS copolymer Hals hybrid polymer (manufactured by Nippon Shokubai Co., Ltd., Hals Hybrid UV-G300, hydroxyl value ( Varnish value): 39 ± 8) 100 parts by weight, 13 parts by weight of a curing agent (Sumitomo Biurethane Co., Ltd., Sumidur N-3200), and a diluting solvent (ethyl acetate) were mixed so as to have a nonvolatile content of 20%. Next, using a bar coater, the mixture was applied so that the thickness after drying was 5 μm, then dried at 120 ° C. for 2 minutes, and then subjected to accelerated curing (2 days at 60 ° C.) to form a hard coating layer An attached resin film was obtained.

  Next, a pressure-sensitive adhesive polymer solution in which an acrylic pressure-sensitive adhesive (manufactured by Nitto Denko Corporation, 2-ethylhexyl acrylate pressure-sensitive adhesive) and a cross-linking agent (manufactured by Nippon Polyurethane Industry Co., Ltd., Coronate L) were mixed at a nonvolatile content of 20% by weight on the separator surface. (Acrylic adhesive: crosslinking agent = 100: 3) was applied using an applicator so that the thickness of the adhesive layer after drying was 30 μm. Then, the adhesive layer was formed by drying at 100 degreeC for 2 minutes, and the separator with an adhesive layer was produced. To the separator with the pressure-sensitive adhesive layer, the above-mentioned resin film with a hard coating layer was bonded with a laminator so as not to cause air bubbles and unevenness to obtain a pressure-sensitive adhesive tape.

[Comparative Example 2]
On the olefin film (surface with Ra of 1.04 μm), which is the resin film obtained in Example 1, as a hard coating layer, HALS copolymer Hals hybrid polymer (manufactured by Nippon Shokubai Co., Ltd., Hals Hybrid UV-G300, hydroxyl value ( Varnish value): 39 ± 8) 100 parts by weight, 13 parts by weight of a curing agent (Sumitomo Biurethane Co., Ltd., Sumidur N-3200), and a diluting solvent (ethyl acetate) were mixed so as to have a nonvolatile content of 20%. Next, using a bar coater, the above mixture was applied so that the thickness after drying was 20 μm, then dried at 120 ° C. for 2 minutes, and then subjected to accelerated curing (2 days at 60 ° C.) to form a hard coating layer An attached resin film was obtained.

  Next, a pressure-sensitive adhesive polymer solution in which an acrylic pressure-sensitive adhesive (manufactured by Nitto Denko Corporation, 2-ethylhexyl acrylate pressure-sensitive adhesive) and a cross-linking agent (manufactured by Nippon Polyurethane Industry Co., Ltd., Coronate L) were mixed at a nonvolatile content of 20% by weight on the separator surface. (Acrylic adhesive: crosslinking agent = 100: 3) was applied using an applicator so that the thickness of the adhesive layer after drying was 30 μm. Then, the adhesive layer was formed by drying at 100 degreeC for 2 minutes, and the separator with an adhesive layer was produced. To the separator with the pressure-sensitive adhesive layer, the above-mentioned resin film with a hard coating layer was bonded with a laminator so as not to cause air bubbles and unevenness to obtain a pressure-sensitive adhesive tape.

[Comparative Example 3]
Homo polypropylene resin (Homo-PP) (Nippon Polychem, FY4), linear low density polyethylene (LDPE) (Sumitomo Chemical, Sumikasen G-401), and r-TPO resin (reactor (polymerization type) olefin) Thermoplastic elastomer) (manufactured by Sun Allomer Co., Ltd., X500F) was extruded at a ratio of homo-PP: LDPE: r-TPO resin = 60 parts by weight: 20 parts by weight: 20 parts by weight (GM Engineering, GM30). -28 extruder), and molded into a melt-extruded sheet (thickness: 100 μm) from a T-die film forming apparatus (manufactured by GMM Engineering, T300T die) to obtain an olefin film as a resin film. Under the present circumstances, the cast roll was prepared so that resin film surface roughness Ra might be set to 0.15 micrometer.

  Next, on this olefin film (the surface where Ra is 0.15 μm), as a hard coating layer, HALS copolymerized Halus hybrid polymer (manufactured by Nippon Shokubai Co., Ltd., Hals Hybrid UV-G300, hydroxyl value (varnish value): 39 ± 8) 100 parts by weight, 13 parts by weight of a curing agent (Sumidule N-3200, manufactured by Sumitomo Biurethane Co., Ltd.) and a diluting solvent (ethyl acetate) are mixed so as to have a non-volatile content of 20%, and then using a bar coater. The mixture was coated so that the thickness after drying was 5 μm, dried at 120 ° C. for 2 minutes, and then subjected to accelerated curing (2 days at 60 ° C.) to obtain a resin film with a hard coating layer.

  Next, a pressure-sensitive adhesive polymer solution in which an acrylic pressure-sensitive adhesive (manufactured by Nitto Denko Corporation, 2-ethylhexyl acrylate pressure-sensitive adhesive) and a cross-linking agent (manufactured by Nippon Polyurethane Industry Co., Ltd., Coronate L) were mixed at a nonvolatile content of 20% by weight on the separator surface. (Acrylic adhesive: crosslinking agent = 100: 3) was applied using an applicator so that the thickness of the adhesive layer after drying was 30 μm. Then, the adhesive layer was formed by drying at 100 degreeC for 2 minutes, and the separator with an adhesive layer was produced. To the separator with the pressure-sensitive adhesive layer, the above-mentioned resin film with a hard coating layer was bonded with a laminator so as not to cause air bubbles and unevenness to obtain a pressure-sensitive adhesive tape.

[Comparative Example 4]
On the olefin film (surface with Ra of 0.15 μm), which is a resin film produced in Comparative Example 3, as a hard coating layer, HALS copolymerized Halus hybrid polymer (manufactured by Nippon Shokubai Co., Ltd., Hals Hybrid UV-G300, hydroxyl value ( Varnish value): 39 ± 8) 100 parts by weight, 13 parts by weight of a curing agent (Sumitomo Biurethane Co., Ltd., Sumidur N-3200), and a diluting solvent (ethyl acetate) were mixed so as to have a nonvolatile content of 20%. Next, using a bar coater, the above mixture was applied so that the thickness after drying was 20 μm, then dried at 120 ° C. for 2 minutes, and then subjected to accelerated curing (2 days at 60 ° C.) to form a hard coating layer An attached resin film was obtained.

  Next, a pressure-sensitive adhesive polymer solution in which an acrylic pressure-sensitive adhesive (manufactured by Nitto Denko Corporation, 2-ethylhexyl acrylate pressure-sensitive adhesive) and a cross-linking agent (manufactured by Nippon Polyurethane Industry Co., Ltd., Coronate L) were mixed at a nonvolatile content of 20% by weight on the separator surface. (Acrylic adhesive: crosslinking agent = 100: 3) was applied using an applicator so that the thickness of the adhesive layer after drying was 30 μm. Then, the adhesive layer was formed by drying at 100 degreeC for 2 minutes, and the separator with an adhesive layer was produced. To the separator with the pressure-sensitive adhesive layer, the above-mentioned resin film with a hard coating layer was bonded with a laminator so as not to cause air bubbles and unevenness to obtain a pressure-sensitive adhesive tape.

  According to the above method, the gloss value was measured, and weatherability stability, scratch resistance, rebound resistance, cracking, and solvent resistance were evaluated. The obtained results are shown in Table 1.

  From the results of Table 1 above, when the pressure-sensitive adhesive tapes having the configuration of the present invention were used (Examples 1 to 3), any of the examples was used even though the surface roughness Ra of the resin film was 1.04. In addition, it was found that the gloss value was as high as 90, and that the weatherability stability, scratch resistance, resilience resistance, cracking, and solvent resistance were all good.

  On the other hand, when the thickness of the hard coating layer is 5 μm (Comparative Examples 1 and 3), in any of the comparative examples, the scratch resistance is poor, and the surface roughness Ra of the resin film is 1.04. If there was, the gross value was as low as 30. Further, when thick coating (the thickness of the hard coating layer was 20 μm) (Comparative Examples 2 and 4), in any of the comparative examples, the resilience resistance was poor and cracking occurred.

  Therefore, it was confirmed that the pressure-sensitive adhesive composition of the present invention is a pressure-sensitive adhesive tape having high glossy design properties and excellent curved surface followability, solvent resistance, scratch resistance, and weather resistance stability.

Cross-sectional view of the main part showing an example of uneven surface of the separator for forming uneven grooves Sectional drawing showing an example of adhesive tape configuration

Claims (6)

A pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer formed on one side of a resin film,
On the other surface of the resin film, a smooth film having a surface roughness Ra of 0.5 μm or less is provided via a binder layer,
Ri thickness 3~25μm der of the smoothing film,
Pressure-sensitive adhesive tape wherein the resin film and / or the smoothing film, characterized in Rukoto comprising a thermosetting acryl-based hard coating layer having a thickness of 1~20μm on at least one surface. A pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer formed on one side of a resin film,
On the other surface of the resin film, a smooth film having a surface roughness Ra of 0.5 μm or less is provided via a binder layer,
The pressure-sensitive adhesive tape, wherein the resin film and / or the smooth film includes a hard coating layer on at least one surface.   The adhesive tape according to claim 1 or 2, wherein the binder layer has a thickness of 1 to 200 µm.   The pressure-sensitive adhesive tape according to any one of claims 1 to 3, wherein the surface roughness Ra of the surface of the resin film in contact with the smooth film is 0.5 to 5.0 µm. The pressure-sensitive adhesive tape according to any one of claims 2 to 4, wherein the resin film and / or the smooth film includes a thermosetting acrylic hard coating layer having a thickness of 1 to 20 µm on at least one surface.   The adhesive tape according to any one of claims 1 to 5, wherein a gloss value of at least one side of the adhesive tape is 40 or more.

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