JP6619259B2 - Adhesive film and method for producing the same - Google Patents

Description

  The present invention relates to an adhesive film and a method for producing the same.

  The pressure-sensitive adhesive film is composed of a base sheet, a pressure-sensitive adhesive layer formed on the surface thereof, and a release sheet provided on the pressure-sensitive adhesive layer. In use, the release sheet is peeled off and the pressure-sensitive adhesive layer is attached. Affix to the body.

  When sticking, spray water or an aqueous solution containing a surfactant on the bonding surface of the adherend or the adhesive layer of the adhesive film so that air does not enter between the adhesive film and the adherend. In general, so-called water pasting is performed, in which both are brought into close contact with each other, and then, with a squeegee, water and the like are scraped and pasted together with air from the adhesive film side. When water intervenes between the adherend and the adhesive film, the adhesiveness is not exhibited, the alignment becomes easy, and the adhesiveness is expressed by scraping out the water.

  To apply so that air or water does not remain when applying water, skill of the practitioner is required, and when applying to a adherend with a large construction area or curved surface In some cases, the construction time required a great deal of time. In addition, when air or water remains, the appearance of the adhesive film attached may become cloudy, or the adhesive layer may become soft due to the remaining water, and there may remain a stamp mark during construction. When the film is transparent, white turbidity, imprints and the like are visually recognized. Therefore, the remaining air or water during construction is a particularly serious problem in a film that requires transparency.

  In order to solve the above-described problems, in Patent Document 1, in an automobile coating film protective film composed of an adhesive layer and a plastic film, the center line average roughness of the plastic surface is 0.1 to 100 μm. It is disclosed that when the film is processed and conveyed in a roll shape, the unevenness on the film surface is transferred to the pressure-sensitive adhesive layer to form the unevenness on the adherend-adhered surface of the pressure-sensitive adhesive layer. Thereby, it is said that air easily escapes at the time of coating due to a gap formed between appropriate irregularities on the surface of the pressure-sensitive adhesive layer and the surface of the vehicle body.

  Moreover, in patent document 2, an unevenness | corrugation is transcribe | transferred to an adhesive surface by apply | coating a pressure sensitive adhesive solution on the peeling liner which has a groove | channel, and air and water are discharged | emitted by forming a groove | channel on the adhesive surface. It is disclosed to form a flow path for the purpose. Specifically, the embossing roll is cut with a diamond tool, or a pattern is formed on the embossing roll using laser processing, and the release liner is raised and processed using this embossing roll to produce a release liner having a fine structure. Then, a pressure-sensitive adhesive solution is applied on the release liner to form an adhesive film having a microstructured surface.

JP 7-89468 A Special Table 2002-544364

  As described in Patent Document 1 above, a method of forming irregularities on both the base material and the pressure-sensitive adhesive, and as disclosed in Patent Document 2, embossing is used to form irregularities on the pressure-sensitive adhesive layer by using a release liner having an irregular shape. Although the method has good air and water discharge properties, the film appearance (transparency) may be impaired. Accordingly, there has been a demand for a film that achieves both transparency and air and water release characteristics.

  Accordingly, an object of the present invention is to provide a pressure-sensitive adhesive film that has good air and water escape and has high transparency.

The present invention has a resin substrate, an adhesive layer, and a release sheet disposed adjacent to the adhesive layer, and the release sheet side surface of the adhesive layer has an uneven shape. The pressure-sensitive adhesive layer side surface of the release sheet has an uneven shape formed by particles, and the ten-point average roughness _RZJIS94 of the pressure-sensitive adhesive layer side surface of the release sheet is 0.6 μm or more. It is an adhesive film.

  According to the present invention, it is possible to provide a pressure-sensitive adhesive film having good transparency of air and water and having high transparency.

FIG. 1 is a schematic cross-sectional view showing an embodiment of the pressure-sensitive adhesive film of the present invention.

  In this specification, “X to Y” indicating a range means “X or more and Y or less”. Unless otherwise specified, operations and measurement of physical properties are performed under conditions of room temperature (20 to 25 ° C.) / Relative humidity of 40 to 50%. Furthermore, in this specification, (meth) acrylic acid means both acrylic acid and methacrylic acid.

1st embodiment of this invention has a resin base material, an adhesive layer, and the peeling sheet arrange | positioned adjacent to this adhesive layer, The peeling sheet side surface of an adhesive layer is uneven | corrugated Having a shape, the pressure-sensitive adhesive layer side surface of the release sheet has an uneven shape formed by particles, and the 10-point average roughness R _ZJIS94 of the pressure-sensitive adhesive layer side surface of the release sheet is 0.6 μm or more, It is an adhesive film. The resin base material, the pressure-sensitive adhesive layer, and the release sheet are arranged in this order.

  FIG. 1 is a schematic cross-sectional view showing an embodiment of the pressure-sensitive adhesive film of the present invention. In FIG. 1, the adhesive film 10 includes a resin base material 11, an adhesive layer 12, and a release sheet 13. The release sheet 13 includes a release substrate 14 and a release agent layer 15. The release sheet may be composed of only the release substrate, but preferably includes a release agent layer in order to improve the peelability.

The release sheet 13 includes particles. In the present embodiment, the particles present in the release sheet 13 protrude toward the pressure-sensitive adhesive layer 12 to form unevenness on the surface. At this time, the ten-point average roughness _{RZJIS94 of the} surface of the release sheet on the pressure-sensitive adhesive layer side is 0.6 μm or more. When affixing to the adherend, the release sheet is peeled off from the adhesive film, but the unevenness formed by transferring the uneven shape formed by particles on the release sheet surface to the release sheet surface of the adhesive layer 12 is formed. A shape exists. Therefore, the convex / concave portions of the release sheet formed by the particles on the release sheet surface become uneven portions on the release sheet side surface of the pressure-sensitive adhesive layer. The convex / concave portion of the release sheet formed by the particles on the release sheet surface becomes an uneven portion on the release sheet side surface of the pressure-sensitive adhesive layer. It can be determined by the correspondence between the concave portion (convex portion) on the surface of the pressure-sensitive adhesive layer.

  When a film is attached to the adherend, the release sheet is peeled off, and the pressure-sensitive adhesive layer surface having an uneven shape is attached to the adherend. By setting it as the adhesive film of said 1st embodiment, when sticking a sheet | seat to a to-be-adhered body by water sticking, while being good in omission of air, water, etc., it becomes an adhesive film with favorable transparency.

  The details of the mechanism by which the pressure-sensitive adhesive film of this embodiment exhibits such an effect are unknown, but are estimated as follows. Since the concavo-convex shape formed by processing such as embossing as described in Patent Documents 1 and 2 is relatively uniform in the depth (height) direction, the concavo-convex shape can be improved by improving water and air exhaustability. It is necessary to increase the depth (height) to some extent. On the other hand, when an attempt is made to increase the depth (height) of the unevenness, the transparency of the pressure-sensitive adhesive layer in which the unevenness is formed is lowered, and the transparency of the entire film may be impaired.

  On the other hand, when the particles in the release sheet protrude to the pressure-sensitive adhesive layer side as in the present embodiment, the particle shape is transferred to the pressure-sensitive adhesive layer-side surface. Depending on the particle shape and particle diameter, and also the dispersibility of the particles, the height, size and variation of the particles protruding from the surface of the release sheet can be controlled to be non-uniform. As a result, the depth (height) and density of the concavo-convex shape present in the pressure-sensitive adhesive layer are relatively irregular. Due to such irregularities in the irregular shape, both the gas and liquid can be smoothly discharged. Furthermore, it is considered that the surface roughness of the concavo-convex shape can be controlled to be relatively small, and it is possible to achieve both the escape of air and water and transparency. The present invention is not limited by the above mechanism.

  The image clarity in the transmission method using an optical comb having a comb width of 0.125 mm as defined by JIS K7374: 2007 of the pressure-sensitive adhesive film from which the release sheet has been peeled is preferably 85% or more (upper limit 100%), More preferably, it is 87% or more (upper limit 100%), and more preferably 90% or more (upper limit 100%). Adhesive film image clarity is in such a range, so that a highly transparent adhesive film can be obtained, which is advantageous in applications requiring high transparency such as window films, display protective films, and coating film protective films. It becomes. The comb width of 0.125 mm is the finest width in the JIS standard, and the above definition in the present invention means that high definition can be obtained even in the fine width.

  Further, the 60-degree specular gloss measured according to JIS Z8741: 1997 of the pressure-sensitive adhesive film from which the release sheet has been peeled is preferably 85% or more and more preferably 90% or more from the viewpoint of transparency. .

  Further, the haze measured according to JIS K7136: 2000 of the pressure-sensitive adhesive film from which the release sheet has been peeled is preferably 1.5% or less, more preferably 1.0% or less, from the viewpoint of transparency. .

  Hereinafter, each structural member which comprises an adhesive film is demonstrated.

(Peeling sheet)
The release sheet is a member that has a function of protecting the pressure-sensitive adhesive layer and preventing a decrease in adhesiveness. And a peeling sheet peels from an adhesive film, when affixing on a to-be-adhered body.

  At least some of the particles in the release sheet protrude to the pressure-sensitive adhesive layer side. For this reason, a peeling sheet contains particle | grains. The arrangement form of the particles in the release sheet may be any form as long as it is present on at least the pressure-sensitive adhesive layer side surface of the release sheet so that the unevenness can be transferred to the pressure-sensitive adhesive layer. Form in which particles are present; a laminated form of a layer containing particles arranged on the pressure-sensitive adhesive layer side and a layer not containing particles arranged on the side facing the pressure-sensitive adhesive layer (for example, particle-containing release agent layer + Any form such as a particle-free release substrate layer) may be used.

  The fact that the uneven shape on the surface of the release sheet is formed of particles can be confirmed by the presence of raised protrusions on the particles by a cross-sectional photograph of the release sheet.

  The particles contained in the release sheet may be either inorganic particles or organic particles. Inorganic particles include metals such as silicon, aluminum, magnesium, zirconium, titanium, zinc, germanium, indium, tin, antimony, cerium, silver; silicon oxide, aluminum oxide, magnesium oxide, zirconium oxide, titanium oxide, zinc oxide, Metal oxides such as germanium oxide, indium oxide, tin oxide, indium tin oxide, antimony oxide, cerium oxide; metal hydroxides such as aluminum hydroxide; metal carbonates such as calcium carbonate and magnesium carbonate; Metal nitride; mica, barium sulfate, silica sand, zeolite and the like.

  Examples of the organic particles include polyethylene, polypropylene, polystyrene, acrylic resin, polycarbonate, polyamide, polyester, and wax.

  One type of particle may be used alone, or two or more types may be used in combination.

  From the viewpoint of forming an uneven shape on the pressure-sensitive adhesive layer, the particles are preferably inorganic particles, and more preferably silicon oxide, calcium carbonate, titanium oxide, and zeolite.

  The shape of the particle is not particularly limited, and examples thereof include a spherical shape, a substantially spherical shape, a flat shape, an indefinite shape, a plate shape, a needle shape, a columnar shape, and a square shape, and a spherical shape, a substantially spherical shape, and a flat shape are preferable.

  The average particle diameter of the particles is preferably 0.5 μm or more, and more preferably 0.5 to 5.0 μm from the viewpoint of forming an uneven shape on the pressure-sensitive adhesive layer. The average particle diameter of the particles is calculated as an average value of the particle diameters of the particles observed in several to several tens of fields using an observation means such as a scanning electron microscope (SEM) or a transmission electron microscope (TEM). The value shall be adopted. The “particle diameter” means the maximum distance among the distances between any two points on the particle outline.

The ten-point average roughness _RZJIS94 of the release sheet side surface of the release sheet is 0.6 μm or more. When the ten-point average roughness _{RZJIS94 of the} surface of the release sheet on the pressure-sensitive adhesive layer side is less than 0.6 μm, the water sticking property is deteriorated, for example, water leakage is reduced or a residual mark is generated. From the viewpoint of water sticking characteristics, the ten-point average roughness _RZJIS94 of the pressure-sensitive adhesive layer side surface of the release sheet is preferably 0.8 μm or more. On the other hand, from the viewpoint of the transparency of the film, the ten-point average roughness _RZJIS94 of the pressure-sensitive adhesive layer side surface of the release sheet is preferably 3.0 μm or less, more preferably 2.0 μm or less. From the viewpoint of transferability to the pressure-sensitive adhesive layer and further transparency, the thickness is more preferably 0.8 to 2.0 μm. In this specification, the ten-point average roughness _RZJIS94 is a value measured with a contact-type surface roughness meter (for example, manufactured by Mitutoyo Corp .; _Surftest Extreme SV-3000 CNC) according to JIS B0601: 1994.

  In addition, the arithmetic average roughness Ra of the pressure-sensitive adhesive layer side surface of the release sheet is preferably 500 nm or less from the viewpoint of transparency of the film, and 200 to 200 from the viewpoint of transferability to the pressure-sensitive adhesive layer and transparency. More preferably, it is 400 nm. In this specification, the arithmetic average roughness Ra is a value measured with an optical interference type surface roughness meter (for example, Wyko NT1100 manufactured by Veeco) according to JIS B0601: 1994.

  The surface roughness of the release sheet on the pressure-sensitive adhesive layer side can be adjusted to be in the above range in consideration of the shape of the particles, the particle diameter, the blending amount of the particles, the thickness of the release agent layer, and the like. Moreover, in order to adjust the surface roughness, particles having various shapes may be combined.

  The surface roughness on the pressure-sensitive adhesive layer side of the release sheet may be measured by measuring the surface roughness of the pressure-sensitive adhesive layer surface of the release sheet after peeling the release sheet from the pressure-sensitive adhesive film. You may measure the surface roughness of a formation surface. In addition, the surface roughness of the pressure-sensitive adhesive layer surface after peeling the release sheet from the pressure-sensitive adhesive film and the surface roughness of the release sheet at the manufacturing stage are substantially the same.

  The content of the particles in the release sheet is preferably 0.5 to 5.0% by mass, and 1.0 to 5.0% by mass from the viewpoint of surface roughness and transferability with respect to the release sheet solid content. % Is more preferable.

  The average thickness of the release sheet is preferably 25 to 100 μm from the viewpoint of ease of release and workability. Here, the average thickness employs a value obtained by averaging the thicknesses of 10 points.

  The release substrate is not particularly limited as long as it has a function of supporting the release agent layer. Especially, it is preferable that a peeling base material is a resin film which contains resin as a binder from viewpoints, such as a dispersibility of particle | grains. The resin contained in the release substrate is not particularly limited, and examples thereof include polyesters such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, polyolefins such as polypropylene and polyethylene, and polycarbonate.

  Commercially available products may be used as the release substrate. Examples of commercially available products include Lumirror X42, X43, X44 manufactured by Toray Industries, Inc .; TORAY ADVANCED MATERIALS KOREA INC. 50XZ31, 32 manufactured; U4 manufactured by Teijin DuPont Films Ltd.

  The release agent layer is provided so that the pressure-sensitive adhesive layer can be easily peeled from the release sheet when the sheet is attached to the adherend. Specific examples of release agents that can be used in the release agent layer include silicone release agents, alkyl pendant release agents, condensation wax release agents, fluorine release agents, rubber release agents, and polyester release agents. Can be mentioned. Especially, since it is easy to maintain peelability and the unevenness | corrugation of a peeling base material, it is preferable that they are a silicone type release agent and a fluorine-type release agent. The thickness of the release agent layer is more preferably 50 to 500 nm in order to exhibit the function as a release agent while maintaining the unevenness formed by particles on the release sheet.

  The release sheet may contain other optional components. Examples of optional components include flame retardants, antistatic agents, leveling agents, dispersion stabilizers, viscosity modifiers, and the like.

(Adhesive layer)
The release sheet side surface of the pressure-sensitive adhesive layer has an uneven shape. It can be confirmed that the release sheet side surface of the pressure-sensitive adhesive layer has an uneven shape by observing the pressure-sensitive adhesive layer surface after peeling the release sheet. This uneven | corrugated shape is formed corresponding to the uneven shape of a peeling sheet. The uneven shape of the release sheet side surface of the release sheet and the uneven shape of the release sheet side surface of the adhesive layer correspond to the projections (recesses) of the release sheet surface by observation means such as an electron microscope. ) And the concave portion (convex portion) on the surface of the pressure-sensitive adhesive layer can be discriminated.

  Since the uneven shape formed in the pressure-sensitive adhesive layer is formed by particles protruding from the surface of the release sheet, the uneven shape in the height direction is relatively irregular. For this reason, since the discharge of both air and water proceeds smoothly, it is considered that both the escape of air and water and transparency can be achieved without particularly increasing the surface roughness. . In addition, since the uneven shape formed on the pressure-sensitive adhesive layer is formed by particles protruding on the surface of the release sheet, the uneven shape corresponds to the particle convex portion and depends on the particle shape. The shape is not a rectangular parallelepiped groove like embossing, but a crater-like depression.

The ten-point average roughness _RZJIS94 of the release sheet side surface of the pressure-sensitive adhesive layer is preferably 0.6 μm or more and 0.8 μm or more from the viewpoint of water sticking characteristics, as is the surface roughness of the release sheet. It is more preferable. On the other hand, it is preferable that it is 3.0 micrometers or less from a viewpoint of the transparency of a film similarly to the surface roughness of a peeling sheet, and it is more preferable that it is 2.0 micrometers or less. From the viewpoint of water sticking characteristics and further transparency, it is more preferably 0.8 to 2.0 μm. Further, the arithmetic average roughness Ra of the release sheet side surface of the pressure-sensitive adhesive layer is preferably 500 nm or less from the viewpoint of the transparency of the film, similarly to the surface roughness of the release sheet. From this viewpoint, the thickness is more preferably 200 to 400 nm.

  It does not specifically limit as an adhesive used for an adhesive layer, An acrylic adhesive, a rubber adhesive, a silicone adhesive, a urethane adhesive, a polyester adhesive, etc. can be used. The pressure-sensitive adhesives may be used alone or in combination of two or more.

  As the pressure-sensitive adhesive, an acrylic pressure-sensitive adhesive can be particularly preferably used from the viewpoint of reliability of adhesion. The acrylic polymer that constitutes the acrylic adhesive is a monomer (copolymerizable) that has (meth) acrylic acid alkyl ester as the main monomer component and can be copolymerized with (meth) acrylic acid alkyl ester as necessary. Monomer). Examples of (meth) acrylic acid alkyl esters include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, (meth) Isobutyl acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, decyl (meth) acrylate, (meth ) Dodecyl acrylate, myristyl (meth) acrylate, palmityl (meth) acrylate, stearyl (meth) acrylate, and the like. These may be used alone or in combination of two or more.

  Examples of acrylic copolymerizable monomers copolymerizable with alkyl (meth) acrylate include 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, and (meth) acrylic. 2- (n-propoxy) ethyl acid, 2- (n-butoxy) ethyl (meth) acrylate, 3-methoxypropyl (meth) acrylate, 3-ethoxypropyl (meth) acrylate, 2- (n (Propoxy) propyl, (meth) acrylic acid 2- (n-butoxy) propyl (meth) acrylic acid alkoxyalkyl esters such as; (meth) acrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, isocrotonic acid, etc. Carboxyl group-containing monomers or anhydrides thereof; sulfonic acid group-containing monomers such as sodium vinyl sulfonate; Aromatic vinyl compounds such as len and substituted styrene; cyano group-containing monomers such as acrylonitrile; olefins such as ethylene, propylene and butadiene; vinyl esters such as vinyl acetate; vinyl chloride; acrylamide, methacrylamide and N-vinyl Amide group-containing monomers such as pyrrolidone and N, N-dimethylacrylamide; Hydroxyl group-containing monomers such as hydroxyalkyl (meth) acrylate and glycerol dimethacrylate; Aminoethyl (meth) acrylate and (meth) acrylyl Amino group-containing monomers such as morpholine; Imido group-containing monomers such as cyclohexylmaleimide and isopropylmaleimide; Epoxy group-containing monomers such as glycidyl (meth) acrylate and methyl glycidyl (meth) acrylate; 2-methacryloyl Isocyanate group-containing monomers such as oxyethyl isocyanate; triethylene glycol diacrylate, diethylene glycol diacrylate, ethylene glycol diacrylate, tetraethylene glycol diacrylate, neopentyl glycol diacrylate, 1,6-hexanediol diacrylate, trimethylol Examples thereof include a copolymerizable monomer (multifunctional group monomer) such as propane triacrylate, pentaerythritol triacrylate, dipentaerythritol hexaacrylate, and divinylbenzene. These may be used alone or in combination of two or more.

  The pressure-sensitive adhesive preferably contains a crosslinking agent in addition to the acrylic polymer. Examples of the crosslinking agent include an isocyanate crosslinking agent, an epoxy crosslinking agent, and a metal chelate crosslinking agent. The addition amount of the crosslinking agent is preferably 0.001 to 10 parts by mass and more preferably 0.005 to 0.5 parts by mass with respect to 100 parts by mass of the acrylic polymer.

  If necessary, a colorant, a filler, an antistatic agent, a tackifier, a wetting agent, a leveling agent, a thickener, an antifoaming agent, an antiseptic, and the like can be appropriately added to the pressure-sensitive adhesive layer.

  Although the thickness of an adhesive layer is not specifically limited, From the viewpoint of adhesiveness and film thickness reduction, the range of 10-100 micrometers is preferable.

(Resin base material)
Examples of the resin substrate include polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, polyvinyl chloride, polystyrene, polyurethane, polycarbonate, polyamide, polyimide, polyetherimide, and poly (meta ) Acrylic acid ester, polybutene, polybutadiene, polymethylpentene, acrylic urethane, ethylene vinyl acetate copolymer, ethylene (meth) acrylic acid copolymer, ethylene (meth) acrylic acid ester copolymer, ABS resin, ionomer resin, It is possible to use a film made of at least one resin selected from various thermoplastic elastomers, or a single type or a plurality of types of laminated films selected from them. That.

  In the present invention, even if it is affixed to an adherend having a curved surface shape, from the viewpoint of good water pasting characteristics and maintaining a transparent appearance, the resin base material has a curved surface shape. It is preferable to use polyurethane having high followability.

  As the polyurethane, polyester-based urethane resin, polyether-based urethane resin, polycarbonate-based urethane resin, or the like can be used. Since the elongation at break is large, a thermoplastic elastomer obtained by polymerizing diisocyanate, a low molecular weight diol having a molecular weight of 500 or less and a high molecular weight diol having a molecular weight of 500 to 4000 as a chain extender is preferable.

  The resin substrate may be a stretched film, an unstretched film, or may be formed by a casting method using a process material.

  It is preferable that the resin base material is transparent so that the adherend can be visually recognized. Here, “transparent” means that the transmittance in the visible light region is 80% or more, and preferably 90% or more. Here, the transmittance of the resin base material can be measured by JIS K7361-1: 1997 (plastic-transparent material total light transmittance test method).

  One or both surfaces of the resin base material can be subjected to a surface treatment such as a primer treatment, an oxidation method, or a concavo-convex method for the purpose of improving the adhesion between adjacent layers. The liquid agent that can be used for the primer treatment is not particularly limited, and conventionally known ones such as acrylic, polyester, polyurethane, silicone, and rubber can be used. On the other hand, examples of the oxidation method include corona discharge treatment, plasma discharge treatment, chromium oxidation treatment (wet), flame treatment, hot air treatment, ozone, ultraviolet irradiation treatment, and the like. Method, thermal spraying method and the like. These surface treatment methods are appropriately selected according to the type of the resin base material.

  For resin base materials, stabilizers, lubricants, fillers, colorants, processing aids, softeners, metal powders, antifogging agents, UV absorbers, antioxidants, antistatic agents, anti-twisting as necessary An agent and the like may be appropriately contained. As the stabilizer, for example, a Ba-Zn-based, Cd-Ba-based, Sn-based or the like may be used, or these may be used in combination with epoxidized soybean oil, epoxy resin, or the like. As the softening agent, for example, an ethylene / vinyl acetate copolymer, an ethylene / vinyl acetate / carbon monoxide copolymer, or the like may be used.

  The thickness of the resin base material may be appropriately set depending on the application. For example, in the case of the polyurethane base material, the thickness is preferably about 20 to 500 μm.

  The resin base material can be manufactured by a conventionally known general method. For example, it can be produced by a known method such as extrusion molding, calendar molding, injection molding, hollow molding, compression molding and the like. In addition, a stretched film may be prepared from an unstretched resin base material using a known method such as uniaxial stretching, tenter-type sequential biaxial stretching, tenter-type simultaneous biaxial stretching, tubular simultaneous biaxial stretching, or the like. it can.

(Other layers)
The adhesive film may be laminated with other layers depending on the intended use.

  Examples of other layers include various functional layers. As functional layers, surface protective layer, antistatic layer, smoothing layer, adhesion improving layer, light shielding layer, antireflection layer, hard coat layer, stress relaxation layer, antifogging layer, antifouling layer, infrared absorption layer, infrared reflection layer A layer, an ultraviolet reflective layer, and the like.

(Method for producing adhesive film)
Another embodiment of the present invention is a method for producing an adhesive film having a resin substrate, an adhesive layer, and a release sheet disposed adjacent to the adhesive layer, and is formed of particles. Including a step of forming a pressure-sensitive adhesive layer having a concavo-convex shape on the surface thereof by transferring the concavo-convex shape onto a release sheet having a concavo-convex shape, the ten-point average roughness of the pressure-sensitive adhesive layer side forming surface of the release sheet It is a manufacturing method of the adhesive film whose _RZJIS94 is 0.6 _micrometer or more. Such a production method is preferable because the unevenness on the surface of the release sheet can be easily transferred to the pressure-sensitive adhesive layer side, and the uneven shape of the pressure-sensitive adhesive layer having a desired surface roughness can be easily formed.

Particles protrude from the surface of the release sheet. At this time, the ten-point average roughness _RZJIS94 of the pressure-sensitive adhesive layer forming surface of the release sheet is 0.6 μm or more. When the ten-point average roughness _{RZJIS94 of the} surface of the release sheet on the pressure-sensitive adhesive layer side is less than 0.6 μm, the water sticking property is deteriorated, for example, water leakage is reduced or a residual mark is generated. From the viewpoint of water sticking characteristics, the ten-point average roughness _RZJIS94 of the pressure-sensitive adhesive layer side surface of the release sheet is preferably 0.8 μm or more. On the other hand, from the viewpoint of the transparency of the film, the ten-point average roughness _RZJIS94 of the pressure-sensitive adhesive layer side surface of the release sheet is preferably 3.0 μm or less, more preferably 2.0 μm or less. From the viewpoint of transferability to the pressure-sensitive adhesive layer and further transparency, the thickness is more preferably 0.8 to 2.0 μm. In addition, the arithmetic average roughness Ra of the pressure-sensitive adhesive layer forming surface of the release sheet is preferably 500 nm or less from the viewpoint of transparency of the film, and 200 to 200 from the viewpoint of transferability to the pressure-sensitive adhesive layer and transparency. More preferably, it is 400 nm. The surface roughness of the release sheet can be adjusted to be in the above range in consideration of the shape of the particles, the particle diameter, the blending amount of the particles, the thickness of the release agent layer, and the like. Moreover, in order to adjust the surface roughness, particles having various shapes may be combined.

Although it does not specifically limit as a manufacturing method of a peeling sheet, The method of apply | coating a peeling agent etc. on the peeling base material with which the particle | grains are disperse | distributed to the whole is mentioned. Such a release substrate can be produced by forming a mixture of a binder resin and particles into a sheet. Moreover, as above-mentioned, you may use a commercial item as a peeling base material. Furthermore, as a method for producing the release sheet, the release sheet surface may be roughened by spraying the resin release substrate with inorganic particles such as silica and titania. The inorganic particles can be sprayed using compressed air. In this method, a desired _RZJIS94 value can be obtained by appropriately adjusting the particle size and the spraying amount of the inorganic particles. As a binder for dispersing the particles, it is preferable that the release sheet, particularly the release substrate, contains a resin.

  The method for applying the release agent is not particularly limited. For example, the release agent may be applied using a known coating apparatus such as a roll coater, knife coater, air knife coater, bar coater, blade coater, slot die coater, lip coater, or gravure coater. Can do.

  After applying the release agent, a drying process is usually performed. It does not specifically limit as drying conditions in this case, Usually, it carries out on the conditions for 1 to 60 seconds at 60-150 degreeC.

  Although the formation method of the adhesive layer on a peeling sheet is not specifically limited, For example, the method of apply | coating an adhesive on a peeling sheet is mentioned. By applying a pressure-sensitive adhesive on the release sheet and drying to form a pressure-sensitive adhesive layer, the uneven shape due to the particles on the release sheet is efficiently transferred to the pressure-sensitive adhesive layer, thereby forming a pressure-sensitive adhesive layer having irregularities. Can do.

The method for applying the adhesive is not particularly limited. For example, the adhesive may be applied using a known coating apparatus such as a roll coater, knife coater, air knife coater, bar coater, blade coater, slot die coater, lip coater, or gravure coater. it can. The coating amount of the adhesive, on a solids by weight, usually 10 to 100 g / ^{m 2,} preferably 20 to 60 g / ^{m 2.} An adhesive layer is formed by performing a drying process after apply | coating an adhesive on a base material. It does not specifically limit as drying conditions in this case, Usually, it carries out on the conditions for 10 to 60 second at 60-150 degreeC.

  Moreover, an adhesive film is not limited to the form manufactured by the said embodiment, After forming an adhesive layer on a resin base material, you may manufacture by bonding a peeling sheet. At this time, in order to transfer unevenness on the surface of the release sheet to the surface of the pressure-sensitive adhesive layer, a method of pressing or a method in which the release sheet and the pressure-sensitive adhesive layer are placed on a heated roll and pressed between the opposing rolls. Etc. may be performed.

(Applications and usage)
The pressure-sensitive adhesive film of the present invention is preferably used when it is applied to an adherend by water sticking, because it has good air escape and water escape, and is also highly transparent. It is preferable to use it for a certain application. Such applications include various types of window films such as heat shield films, anti-scatter films, and UV shield films, various protective films that protect coating surfaces and liquid crystal surfaces of vehicles, clear films for imparting gloss, Laminate film etc. are mentioned.

  Examples of the adherend include various adherends such as metal, glass, and plastic. Examples of the metal include steel, stainless steel, aluminum, copper, nickel, chromium and alloys thereof. Also, it can be applied to a composite material having a metal plating layer on the surface, and the base material for plating in that case is not particularly limited as long as it can be plated, and may be various materials such as metal, glass and plastic. Good. Examples of the glass include alkali glass, non-alkali glass, and quartz glass. Examples of the plastic include polyolefin resins such as high density polyethylene (HDPE), ultra high molecular weight polyethylene (UHMWPE), isotactic polypropylene, syndiotactic polypropylene, ethylene propylene copolymer resin; nylon 6 (N6), nylon 66 ( N66), nylon 46 (N46), nylon 11 (N11), nylon 12 (N12), nylon 610 (N610), nylon 612 (N612), nylon 6/66 copolymer (N6 / 66), nylon 6/66 / 610 copolymer (N6 / 66/610), nylon MXD6 (MXD6), nylon 6T, nylon 6 / 6T copolymer, nylon 66 / PP copolymer, nylon 66 / PPS copolymer, and other polyamide resins ; Polybutylene terephthalate (P T), polyethylene terephthalate (PET), polyethylene isophthalate (PEI), PET / PEI copolymer, polyarylate (PAR), polybutylene naphthalate (PBN), liquid crystal polyester, polyoxyalkylene diimide diacid / polybutyrate Aromatic polyester resins such as terephthalate copolymer; polyacrylonitrile (PAN), polymethacrylonitrile, acrylonitrile / styrene copolymer (AS), methacrylonitrile / styrene copolymer, methacrylonitrile / styrene / butadiene copolymer Polymer), polymethacrylate resins (for example, polynitrile resins such as polymethyl methacrylate (PMMA) and polyethyl methacrylate; vinyl acetate (EVA), polyvinyl alcohol (PVA), vinyl alcohol / Polyvinyl resins such as ethylene copolymer (EVOH), polyvinylidene chloride (PVDC), polyvinyl chloride (PVC), vinyl chloride / vinylidene chloride copolymer, vinylidene chloride / methyl acrylate copolymer; .

  It is preferable that the pressure-sensitive adhesive film of the first embodiment is stuck after the pressure-sensitive adhesive layer is brought into contact with the adherend after the release sheet is peeled off. At this time, since the effect of the present invention is more exhibited, it is preferable to use so-called water sticking. Moreover, since the adhesive film of 1st embodiment is very favorable in the discharge | emission property of air or water, since the effect of this invention is more easily exhibited when it uses for the adherend which has a curved surface shape, it is preferable. Examples of such adherends include curved windows and painted surfaces of moving bodies (particularly vehicles). Although it does not specifically limit as a moving body, For example, moving bodies, such as a vehicle, an aircraft, a ship, a bulldozer, a shovel car, a truck crane, a forklift, are mentioned. Vehicles include automobiles that use gasoline or bioethanol as fuel, electric vehicles that use secondary batteries or fuel cells, and four-wheeled vehicles such as hybrid vehicles (passenger cars, trucks, buses, etc.); motorcycles, bicycles; railways Vehicles (trains, hybrid trains, locomotives, etc.) are examples.

  The effects of the present invention will be described using the following examples and comparative examples. However, the technical scope of the present invention is not limited only to the following examples. Unless otherwise specified, each operation is performed at room temperature (25 ° C.).

Example 1
(Peeling sheet)
As a release substrate, Lumirror (registered trademark) X44 (particle-containing biaxially stretched polyethylene terephthalate film, thickness 50 μm) manufactured by Toray Industries, Inc. was used. After the silicone release agent was dried on the release substrate, the film thickness was 200 nm. It was coated with a gravure coater and dried at 90 ° C. for 30 seconds to obtain a release sheet having a _{RZJIS 94} of 1.0 μm on one side.

(Adhesive layer)
In a flask equipped with a reflux condenser and a stirrer, 95 parts by mass of butyl acrylate, 5 parts by mass of acrylic acid, a peroxide-based initiator and toluene (solvent) are mixed and heated while performing nitrogen substitution to perform polymerization. Thus, an acrylic polymer was obtained (weight average molecular weight Mw = 500,000).

  100 parts by mass of the acrylic polymer solid content and 0.01 parts by mass of an epoxy-based crosslinking agent (trade name: TETRAD-X, manufactured by Mitsubishi Gas Chemical Company) were mixed to obtain a pressure-sensitive adhesive composition.

The pressure-sensitive adhesive composition was coated on the surface of the release sheet having _RZJIS94 of 1.0 μm using a knife coater so that the film thickness after drying was 40 μm, and dried at 100 ° C. for 1 minute.

(Resin base material)
A transparent polyurethane resin film (Lackskin F9700ES-150C, manufactured by Seiko Kasei Co., Ltd.) having a thickness of 150 μm was used as a resin base material. An adhesive film was prepared by sticking an adhesive layer to a resin substrate.

(Example 2)
As a release substrate, Lumirror (registered trademark) X42 (particle-containing biaxially stretched polyethylene terephthalate film, thickness 50 μm) manufactured by Toray Industries, Inc. was used. After the silicone release agent was dried on the release substrate, the film thickness was 200 nm. A pressure-sensitive adhesive film was prepared in the same manner as in Example 1 except that the film was applied with a gravure coater and dried at 90 ° C. for 30 seconds to obtain a release sheet having a single-sided _RZJIS94 of 1.9 μm.

Example 3
As a release substrate, TORAY ADVANCED MATERIALS KOREA INC. Using 50XZ32 (particle-containing biaxially stretched polyethylene terephthalate film, thickness 50 μm), a silicone release agent was applied with a gravure coater so that the film thickness after drying was 200 nm, and dried at 90 ° C. for 30 seconds. A pressure-sensitive adhesive film was produced in the same manner as in Example 1 except that R _ZJIS94 obtained a release sheet having a _size of 2.7 μm.

(Comparative Example 1)
As a release substrate, Diafoil (registered trademark) T-100 (biaxially stretched polyester film, thickness 50 μm) manufactured by Mitsubishi Plastics Co., Ltd. was used, and a silicone release agent was applied with a gravure coater so that the film thickness would be 200 nm after drying. A pressure-sensitive adhesive film was prepared in the same manner as in Example 1 except that it was dried at 90 ° C. for 30 seconds to obtain a release sheet having _RZJIS94 of 0.59 μm on one side.

(Evaluation methods)
1. Water sticking characteristics 0.1% by weight of surfactant [sodium polyoxyethylene alkyl ether sulfate] on one side of a pressure-sensitive adhesive layer of a 25 mm × 300 mm pressure-sensitive adhesive film from which a release sheet has been peeled off and an adherend (3 mm thick glass plate) Salt] After spraying the aqueous solution, an adhesive film was applied to the adherend, and water present at the interface between the adhesive layer and the adherend was scraped with a squeegee to obtain a test sample.

  For water leakage, visually check the remaining water, ◎ if there is no water left, ◯ if there is very little water remaining, but if there is virtually no problem, × if there is a small amount of water remaining. did.

  In addition, the remaining marks were marked as ◯ when there was no change in the appearance, and marked as x when there were some remaining marks.

2. Image clarity The release sheet was peeled off from the adhesive films obtained in Examples and Comparative Examples, and after peeling, attached to the glass surface. After 24 hours, an optical comb having a comb width of 0.125 mm on the adhesive surface side of the adhesive layer The image sharpness was measured.

  Here, the image sharpness is measured by measuring the amount of parallel light transmitted through the test body through an optical comb having a transmission part and a light-shielding part. The smaller the width (comb width) between the transmission part and the light-shielding part in the optical comb, the higher the definition of the image. The image definition is measured according to the transmission method of JIS K7374: 2007, and in this specification, it is a value measured using a image clarity measuring instrument (ICM-1DP manufactured by Suga Test Instruments Co., Ltd.).

3. 60 degree specular glossiness The release sheet was peeled off from the adhesive films obtained in the examples and comparative examples, peeled off, pasted on a black painted plate, 24 hours later, in accordance with JIS Z 8741: 1997, gloss meter (Nippon Denshoku Industries Co., Ltd. Gloss Meter VG7000) measured the 60 degree specular glossiness of the adhesive layer surface.

4). Haze The release sheet was peeled off from the adhesive films obtained in Examples and Comparative Examples, attached to the glass surface after peeling, and 24 hours later, using a haze meter (Nippon Denshoku Industries Co., Ltd., NDH2000), JIS K7136: 2000 The haze (%) was measured according to the above.

  The results are shown in the table below.

  From the above, the adhesive films of Examples 1 to 3 are highly transparent films equivalent to Comparative Example 1, and are films that are remarkably excellent in water sticking characteristics as compared to the adhesive film of Comparative Example 1. I understand.

10 Adhesive film,
11 resin base material,
12 adhesive layer,
13 Release sheet.

Claims (8)

A resin substrate, an adhesive layer, and a release sheet disposed adjacent to the adhesive layer,
The release sheet contains particles,
At least a part of the particles protrudes to the adhesive layer side,
The release sheet side surface of the pressure-sensitive adhesive layer has an uneven shape,
The pressure-sensitive adhesive layer side surface of the release sheet has an uneven shape formed by particles protruding to the pressure-sensitive adhesive layer side ,
Wherein Ri der ten-point average roughness _{R ZJIS94} is 0.6μm or more 3.0μm or less of the release sheet the adhesive layer surface,
Wherein the release sheet ten-point average roughness of the surface _{R ZJIS94} of the pressure-sensitive adhesive layer is Ru der than 3.0μm or less 0.6 .mu.m, the adhesive film. The pressure-sensitive adhesive film according to claim 1 , wherein the uneven shape on the release sheet side surface of the pressure-sensitive adhesive layer is formed corresponding to the uneven shape on the pressure-sensitive adhesive layer side surface of the release sheet . The pressure-sensitive adhesive film according to claim 1 or 2, wherein the ten-point average roughness _{RZJIS94 of the} surface of the release sheet on the pressure-sensitive adhesive layer side is 2.0 µm or less.   The image clarity in the transmission method using an optical comb having a comb width of 0.125 mm defined by JIS K7374: 2007 of the pressure-sensitive adhesive film from which the release sheet has been peeled is 87% or more. The pressure-sensitive adhesive film according to claim 1.   The pressure-sensitive adhesive film according to claim 1, wherein the release sheet has a release substrate, and the release substrate contains a resin. A method for producing a pressure-sensitive adhesive film comprising a resin base material, a pressure-sensitive adhesive layer, and a release sheet disposed adjacent to the pressure-sensitive adhesive layer,
A pressure-sensitive adhesive containing particles, wherein at least a part of the particles protrudes from the surface , and the uneven shape is transferred onto the release sheet having the uneven shape formed by the protruded particles. A method for producing a pressure-sensitive adhesive film, comprising a step of forming a layer, wherein the ten-point average roughness _RZJIS94 of the pressure-sensitive adhesive layer side forming surface of the release sheet is 0.6 μm or more and 3.0 μm or less . The manufacturing method of the adhesive film of Claim 6 whose ten-point average roughness _RZJIS94 of the adhesive layer formation surface of the said peeling sheet is 2.0 _micrometers or less.   The manufacturing method of the adhesive film of Claim 6 or 7 with which the said peeling sheet contains resin.