JP5412344B2 - Laminated film and adhesive tape - Google Patents

Description

  The present invention relates to a laminated film and an adhesive tape. More specifically, the present invention relates to a laminated film and an adhesive tape whose haze value and surface roughness are adjusted without changing the mechanical properties of the entire laminated film or adhesive tape.

  Generally, a film and an adhesive tape are adjusted to the haze value and surface roughness according to the purpose (for example, appearance adjustment). As a method for adjusting the haze value and the surface roughness, a T-die extrusion touch roll molding method, that is, a molten resin extruded through a T-die is brought into contact with a metal roll having an uneven pattern, and the uneven pattern is applied to the resin surface (film surface) There is known a method for transferring the image (for example, Patent Documents 1 and 2).

  However, in the T-die extrusion touch roll molding method, if high-speed molding is performed, there is a problem of processing failure such that the molten resin is wound around the metal roll due to insufficient cooling of the resin, or the uneven pattern of the metal roll is sufficiently transferred to the resin. The problem that it is not done arises.

  Furthermore, in the T-die extrusion touch roll molding method, it is common that unevenness processing is also applied to the surface of the touch roll rubber for the purpose of improving the peelability of the film, and this unevenness affects the haze value of the film. Therefore, there arises a problem that it is difficult to obtain a film having a desired haze value (particularly, a medium / low haze value).

  Examples of film forming methods other than the T-die extrusion touch roll forming method include a T-die air knife forming method and an inflation air cooling forming method. However, since these methods form irregularities on the film surface only by flow deformation from when the resin is melted to when it is cooled and solidified, it is difficult to form precise irregularities on the film surface.

  Even during air-cooling molding, attempts have been made to adjust the haze value by intentionally forming a sea-island phase-separated structure using two or more components that are hardly compatible as film-forming resins. . However, in order to control the sea-island structure of the entire film and adjust the haze value and surface roughness, it is necessary to ensure the thickness of the film accordingly, and it is difficult to reduce the film thickness. Moreover, it is necessary to adjust the composition of the material used for film formation each time according to the desired haze value and surface roughness. As a result, the mechanical properties of the entire film greatly vary with the adjustment of the haze value and the surface roughness. For this reason, it is difficult to independently adjust the mechanical properties of the entire film and the haze value and surface roughness of the film.

JP 2003-181962 A JP 2004-149639 A

  The present invention has been made to solve the above-described conventional problems, and the object of the present invention is to adjust the haze value and the surface roughness without changing the mechanical properties of the entire laminated film or adhesive tape. Another object is to provide a laminated film and an adhesive tape.

The laminated film of the present invention is a laminated film having a base layer and a surface layer, wherein the base layer contains a thermoplastic resin, the surface layer contains polyethylene and a propylene-based polymer, and the arithmetic of the surface layer The average surface roughness Ra is 0.5 μm to 2.0 μm, and the haze value of the laminated film is 13.5% to 80%.
In a preferred embodiment, the laminated film has a haze value of 20% to 80%.
In preferable embodiment, the thickness of the said surface layer is 2 micrometers-10 micrometers.
In a preferred embodiment, the weight ratio of the polyethylene to the propylene polymer is polyethylene: propylene polymer = 10: 90 to 90:10.
In a preferred embodiment, the surface layer has two or more melting temperatures Tm in differential scanning calorimetry.
In a preferred embodiment, the polyethylene has a melt flow rate of 8 g / 10 min to 100 g / 10 min.
In a preferred embodiment, the propylene polymer has a melt flow rate of 0.1 g / 10 min to 7 g / 10 min.
According to another aspect of the present invention, an adhesive tape is provided. This adhesive tape has an adhesive layer on one side of the laminated film.
In preferable embodiment, the haze value of the said adhesive tape is 13.5%-80%.
In a preferred embodiment, the surface layer has a long-chain alkyl release agent.

  According to the present invention, by having a surface layer containing a specific resin, the haze value and the surface roughness can be freely adjusted, so that a laminated film and an adhesive tape according to a desired appearance can be obtained. . In addition, the laminated film and the adhesive tape of the present invention can adjust the haze value and the surface roughness due to the contribution of the surface layer, and the surface layer is substantially very thin. It is possible to obtain a desired haze value and surface roughness without changing the mechanical properties. Furthermore, since the laminated film and the adhesive tape of the present invention are excellent in productivity, they can be obtained at low cost.

It is a schematic sectional drawing of the laminated | multilayer film by preferable embodiment of this invention. It is a schematic sectional drawing of the adhesive tape by preferable embodiment of this invention.

A. Laminated film The laminated film of the present invention has a substrate layer and a surface layer. FIG. 1 is a schematic cross-sectional view of a laminated film according to a preferred embodiment of the present invention. The laminated film 10 includes a base material layer 1 and a surface layer 2 disposed on one side or both sides (one side in the illustrated example) of the base material layer 1. The laminated film of the present invention may further have any appropriate other layer as required (not shown). The other layer may be provided at any position other than the side of the surface layer 2 where the base material layer 1 is not disposed.

  The thickness of the laminated film of the present invention can be set to any appropriate thickness depending on the application. Preferably they are 10 micrometers-200 micrometers, More preferably, they are 10 micrometers-180 micrometers, More preferably, they are 12 micrometers-170 micrometers.

  The haze value of the laminated film of the present invention is 13.5% to 80%, preferably 20% to 80%, more preferably 30% to 80%, and further preferably 35% to 75%. is there. When the haze value of the laminated film is in such a range, the laminated film has an appearance suitable for appearance adjustment.

A-1. Base material layer Arbitrary appropriate thickness can be employ | adopted for the thickness of the said base material layer according to a use. The thickness of the base material layer is preferably 10 μm to 150 μm, and more preferably 20 μm to 100 μm.

  Any appropriate value can be adopted as the haze value of the substrate layer as long as the haze value of the laminated film of the present invention is 13.5% to 80%. Preferably, it is 1% to 80%, more preferably 10% to 60%. When the haze value of the base material layer is in such a range, a laminated film having an appearance suitable for appearance adjustment can be obtained.

  The base material layer includes a thermoplastic resin. Any appropriate resin can be adopted as the thermoplastic resin as long as the film can be formed by melt extrusion. Examples of the thermoplastic resin include polyolefin resins such as propylene-based polymers, polyethylene, olefin-based thermoplastic elastomers (TPO), and modified products thereof; α-olefins and vinyl compounds (for example, vinyl acetate, (meth) acrylic acid esters). Polyamide; Polyester; Polycarbonate; Polyurethane; Polyvinyl chloride; Examples of the propylene-based polymer include homopolypropylene, block polypropylene, and random polypropylene.

  When homopolypropylene is used as the thermoplastic resin, the structure of the homopolypropylene may be isotactic, atactic, or syndiotactic.

  When polyethylene is used as the thermoplastic resin, the polyethylene may be any of low density polyethylene, medium density polyethylene, and high density polyethylene.

  In the said base material layer, the said thermoplastic resin may be used independently and may use 2 or more types together. Combination forms include blending and copolymerization.

  A commercially available product may be used as the thermoplastic resin. Specific examples of commercially available thermoplastic resins include trade name “PF380A” (block polypropylene) manufactured by Sun Allomer.

  The base material layer may contain any appropriate additive as required. Examples of the additive that can be contained in the base material layer include an ultraviolet absorber, a heat stabilizer, a filler, and a lubricant. The kind, number, and amount of additives contained in the base material layer can be appropriately set according to the purpose.

  Examples of the ultraviolet absorber include benzotriazole compounds, benzophenone compounds, benzoate compounds, and the like. Any appropriate content can be adopted as the content of the ultraviolet absorber as long as it does not bleed out during the formation of the laminated film. Typically, it is 0.01 part by weight to 5 parts by weight with respect to 100 parts by weight of the thermoplastic resin in the base material layer.

  Examples of the heat resistance stabilizer include hindered amine compounds, phosphorus compounds, and cyanoacrylate compounds. Any appropriate content can be adopted as the content of the heat-resistant stabilizer as long as it does not bleed out when the laminated film is formed. Typically, it is 0.01 part by weight to 5 parts by weight with respect to 100 parts by weight of the thermoplastic resin in the base material layer.

  Examples of the filler include inorganic fillers such as talc, titanium oxide, calcium carbonate, clay, mica, barium sulfate, whisker, and magnesium hydroxide. The average particle diameter of the filler is preferably 0.1 μm to 10 μm. The content of the filler is preferably 1 part by weight to 200 parts by weight with respect to 100 parts by weight of the thermoplastic resin in the base material layer.

A-2. Surface Layer The thickness of the surface layer is preferably 2 μm to 10 μm, more preferably 2 μm to 8 μm, and particularly preferably 2 μm to 5 μm. When the thickness of the surface layer is less than 2 μm, the desired surface roughness may be difficult to obtain, and a laminated film having a high haze value may be difficult to obtain. When the thickness of the surface layer is greater than 10 μm, the mechanical properties of the surface layer affect the mechanical properties of the entire laminated film, and the handling of the laminated film may be deteriorated.

  As the haze value of the surface layer, any appropriate value can be adopted as long as the haze value of the laminated film of the present invention is 13.5% to 80%. Preferably, it is 13.5% to 80%, more preferably 20% to 80%, still more preferably 30% to 80%, and particularly preferably 35% to 75%. When the haze value of the surface layer is in such a range, a laminated film having an appearance suitable for appearance adjustment can be obtained. The haze value can be measured by a method according to JISK7136.

  The arithmetic average surface roughness Ra of the surface layer is 0.5 μm to 2.0 μm, preferably 0.8 μm to 1.9 μm, and more preferably 1.0 μm to 1.9 μm. When the arithmetic average surface roughness Ra of the surface layer is in such a range, a laminated film having an appearance suitable for appearance adjustment can be obtained.

  The surface layer includes polyethylene and a propylene-based polymer. As a propylene-type polymer, arbitrary appropriate propylene-type polymers can be employ | adopted, for example. Specific examples of the propylene-based polymer include homopolypropylene, block polypropylene, and random polypropylene. Any appropriate weight ratio can be adopted as the weight ratio between the polyethylene and the propylene-based polymer depending on the desired haze value and / or surface roughness. The weight ratio (polyethylene: propylene polymer) is preferably 10:90 to 90:10, more preferably 20:80 to 80:20, and particularly preferably 30:70 to 70:30.

  Preferably, the polyethylene and the propylene-based polymer exhibit different melt flow rates. If the polyethylene and the propylene-based polymer have different melt flow rates, when the surface layer forming material is molded by being stretched in a hot melt state, a resin having a high melt flow rate is easily stretched and a resin having a low melt flow rate is stretched. Since it is difficult, a surface layer having a sea-island structure in which a resin having a high melt flow rate forms a sea portion and a resin having a low melt flow rate forms an island portion can be obtained. As a result, haze values and surface roughness can be expressed in the surface layer due to the unevenness caused by the sea-island structure.

  The melt flow rate of the polyethylene is preferably 8 g / 10 min to 100 g / 10 min, more preferably 9 g / 10 min to 80 g / 10 min, particularly preferably 9 g / 10 min to 50 g / 10 min, and most preferably 10 g. / 10 min to 50 g / 10 min. When the melt flow rate of polyethylene is less than 8 g / 10 min, the difference in melt flow rate between polyethylene and the propylene-based polymer becomes small, and the haze value and surface roughness may be too small. When it is larger than 100 g / 10 min, the haze value and the surface roughness may be too large. The melt flow rate can be measured by a method according to JISK7210.

  The melt flow rate of the propylene polymer is preferably 0.1 g / 10 min to 7 g / 10 min, more preferably 0.2 g / 10 min to 5 g / 10 min, and particularly preferably 0.2 g / 10 min to 3 g / min. 10 min, most preferably 0.4 g / 10 min to 2.8 g / 10 min. When the melt flow rate of the propylene-based polymer is smaller than 0.1 g / 10 min, the haze value and the surface roughness may be too large. If it is larger than 7 g / 10 min, the difference in melt flow rate between polyethylene and the propylene-based polymer becomes small, and the haze value and surface roughness may be too small.

  When the melt flow rate of the polyethylene and the propylene-based polymer is in the above range, a surface layer having a sea-island structure in which polyethylene forms a sea portion and the propylene-based polymer forms an island portion can be obtained.

  The haze value and surface roughness of the laminated film can be controlled by adjusting the difference between the melt flow rate of the polyethylene and the melt flow rate of the propylene-based polymer. That is, when the difference in melt flow rate is large, the difference in easiness of elongation of the surface layer forming material is large, and a surface layer having a clear sea-island structure can be obtained. A film can be obtained. On the other hand, when the difference in melt flow rate is small, the difference in the easiness of elongation of the surface layer forming material is small, and it is difficult to obtain a surface layer having a clear sea-island structure, so a laminated film with a small haze value and surface roughness Can be obtained.

  When the viscosity difference between a low viscosity resin (showing a high melt flow rate) and a high viscosity resin (showing a low melt flow rate) is small, it is difficult to obtain a clear deformation flow difference, and a sea-island structure cannot be obtained, A laminated film having a low haze and a smooth surface roughness can be obtained. On the other hand, when the viscosity difference between a low viscosity resin (showing a high melt flow rate) and a high viscosity resin (showing a low melt flow rate) is large, a clear deformation flow difference can be obtained, and the sea-island structure becomes clear. A laminated film having a high haze and a rough surface can be obtained. The target haze and surface roughness can be controlled by the difference in viscosity of the resin used. In order to obtain a rough surface roughness with high haze, it is preferable that the melting point of the high-viscosity resin having an island structure is higher than that of the low-viscosity resin having a sea structure. This is because the island structure is first cooled and solidified during elongation flow, and the high-viscosity resin of the sea-forming resin is not cooled and solidified when solidified, thereby forming a clear sea-island structure. Therefore, in order to form a rough surface roughness with high haze, it is preferable to use a propylene-based polymer or the like for the high-viscosity resin having an island structure, and to use a low-melting resin such as various polyethylenes for the low-viscosity resin having a sea structure. Is preferred.

  The surface layer preferably has two or more melting temperatures Tm in differential scanning calorimetry (DSC). Such a surface layer can be obtained by using polyethylene and propylene-based polymers having different melting points. By using polyethylene and propylene-based polymers having different melting points for the surface layer, the haze value and surface roughness of the laminated film can be adjusted by the difference in melting point. More specifically, when the film is formed by cooling and solidifying after heat melting, the high melting point propylene-based polymer is solidified first, and then the low melting point polyethylene is solidified. A clear sea-island structure can be obtained in the surface layer, and as a result, a laminated film having a large haze value and surface roughness can be obtained. On the other hand, when the melting point difference is small, it is difficult to obtain a surface layer having a clear sea-island structure, so that a laminated film having a small haze value and surface roughness can be obtained. In addition, the said melting temperature Tm can be measured by the method according to JISK7121. In this specification, “having two or more melting temperatures Tm” means that two or more melting endothermic peaks occur in the DSC curve.

  The melting point of polyethylene is preferably 100 ° C to 125 ° C, more preferably 105 ° C to 125 ° C, further preferably 110 ° C to 125 ° C, and particularly preferably 115 ° C to 120 ° C.

  The melting point of the propylene-based polymer is preferably 125 ° C to 200 ° C, more preferably 125 ° C to 180 ° C, still more preferably 125 to 170 ° C, particularly preferably 125 to 165 ° C, and most preferably. Is 130-165 ° C.

  The difference between the melting point of the polyethylene and the melting point of the propylene-based polymer is preferably 5 ° C to 65 ° C, more preferably 10 ° C to 60 ° C, and particularly preferably 15 ° C to 50 ° C. If the difference between the melting point of polyethylene and the melting point of the propylene-based polymer is within such a range, the laminated film of the present invention, that is, a surface layer having an arithmetic average surface roughness Ra of 0.5 μm to 2.0 μm, and haze A laminated film having a value of 13.5% to 80% can be easily obtained.

  The haze value and surface roughness of the laminated film of the present invention can also be adjusted by the compatibility between the polyethylene and the propylene-based polymer in the surface layer. When the compatibility between the polyethylene and the propylene-based polymer is low, a clear sea-island structure can be obtained in the surface layer, so that a laminated film having a large haze value and surface roughness can be obtained. On the other hand, when the compatibility is high, it is difficult to obtain a clear sea-island structure, and thus a laminated film having a small haze value and surface roughness can be obtained.

  Commercially available products may be used as the polyethylene and the propylene-based polymer.

  Specific examples of commercially available polyethylene include Tosoh's trade name “Petrocene 209”, Nippon Polyethylene's trade names “Novatech LD LJ803”, “Novatech LD LC701”, “Novatech LD LC720”, and the like. Specific examples of commercially available propylene-based polymers include “NOVATEC PP EG8” manufactured by Nippon Polypro Co., Ltd.

  The surface layer may contain any appropriate additive as required. As the additive that can be contained in the surface layer, for example, the additive described in the section A-1 can be used.

A-3. Other Layers The laminated film of the present invention may further have other appropriate other layers as necessary (not shown). The other layer may be provided at any position other than the side of the surface layer where the base material layer is not disposed.

  The thickness of the other layer is preferably 2 μm to 12 μm, and more preferably 5 μm to 10 μm.

  Any appropriate value can be adopted as the haze value of the other layer as long as the haze value of the laminated film of the present invention is 13.5% to 80%.

  As said other layer, a smooth layer is mentioned, for example. For example, when the laminated film has a surface layer on one side of the substrate layer, the smooth layer can be used by being disposed on the side of the substrate layer where the surface layer is not disposed.

  Any appropriate material can be adopted as the material constituting the smooth layer. As a material constituting the smooth layer, for example, a polyolefin resin such as polyethylene, polypropylene, or TPO can be employed. Specifically, various thermoplastic resins such as various polyethylenes having a low density to a high density and various polypropylenes such as isotactic, atactic, and syndiotactic polypropylenes can be used. In addition to polyolefin resins, the main components are modified α-olefins, copolymers of α-olefins with various vinyl compounds such as vinyl acetate and methacrylate, polyamides, polyesters, polycarbonates, polyurethanes, polyvinyl chlorides, and the like. Such a thermoplastic resin may be employed. These materials may be used alone or in combination of two or more.

A-4. Formation method of laminated film The laminated film can be obtained by any appropriate formation method. Typically, a method of co-extruding the base material layer, the surface layer, and another layer as necessary may be mentioned. The co-extrusion method can be performed according to the inflation method, the T-die method, or the like, using an extruder and a co-extrusion die for each layer forming material. Other manufacturing methods include, for example, a method in which a base material layer, a surface layer, and, if necessary, other layers are bonded to each other using any appropriate adhesive by a calender molding method. .

B. Adhesive tape The adhesive tape of this invention has the laminated | multilayer film of this invention, and the adhesive layer arrange | positioned at the one side of the said laminated | multilayer film. FIG. 2 is a schematic cross-sectional view of an adhesive tape according to a preferred embodiment of the present invention. The pressure-sensitive adhesive tape 100 includes a laminated film 10 and an adhesive layer 20 arranged on the side where the surface layer 2 of the laminated film 10 is not arranged. The laminated film 10 constituting the pressure-sensitive adhesive tape of the present invention is the laminated film of the present invention described above, and includes the base material layer 1 described in the section A-1 and the surface layer 2 described in the section A-2. .

  The surface layer used for the pressure-sensitive adhesive tape of the present invention preferably further contains a long-chain alkyl release agent. If the surface layer contains a long-chain alkyl release agent, it is possible to prevent sticking between the surface layer and the pressure-sensitive adhesive layer in a state where the pressure-sensitive adhesive tapes overlap each other, for example, in a roll form. Moreover, since it is not necessary to cover a surface layer with a separator layer, the adhesive tape which has a desired haze value and surface roughness can be obtained easily.

  The long-chain alkyl release agent includes a long-chain alkyl polymer. The long-chain alkyl polymer can be obtained by reacting a polymer having a reactive group with a compound having an alkyl group capable of reacting with the reactive group in any appropriate heating solvent. During the reaction, a catalyst may be used as necessary. Examples of the catalyst include a tin compound and a tertiary amine.

  Examples of the reactive group include a hydroxyl group, an amino group, a carboxyl group, and a maleic anhydride group. Examples of the polymer having a reactive group include an ethylene-vinyl alcohol copolymer, polyvinyl alcohol, polyethyleneimine, polyethyleneamine, and a styrene-maleic anhydride copolymer. Of these, an ethylene-vinyl alcohol copolymer is preferred. The ethylene-vinyl alcohol copolymer is a concept including a partially saponified product of an ethylene-vinyl acetate copolymer. Polyvinyl alcohol is a concept including a partially saponified product of polyvinyl acetate.

  The number of carbon atoms of the alkyl group is preferably 8-30, and more preferably 12-22. When the carbon number of the alkyl group is in such a range, a surface layer having excellent peelability can be obtained. Specific examples of such an alkyl group include a lauryl group, a stearyl group, and a behenyl group. Examples of the compound having an alkyl group (that is, a compound having an alkyl group capable of reacting with the reactive group) include isocyanates such as octyl isocyanate, decyl isocyanate, lauryl isocyanate, stearyl isocyanate; acid chlorides, amines, alcohols, etc. Is mentioned. Of these, isocyanate is preferable.

  The weight average molecular weight of the long-chain alkyl polymer is preferably 10,000 to 1,000,000, and more preferably 20,000 to 1,000,000. When the weight average molecular weight of the long-chain alkyl polymer is in such a range, a surface layer having excellent peelability can be obtained.

  The long-chain alkyl release agent is kneaded into the surface layer when the laminated film or the adhesive tape is coextruded. The content of the long-chain alkyl release agent in the surface layer is preferably 1% by weight to 50% by weight, more preferably 2% by weight to 30% by weight, and particularly preferably 5% by weight to 20% by weight. % By weight. When the content is less than 1% by weight, the effect of adding the long-chain alkyl release agent may not be obtained. When the content ratio is more than 50% by weight, a bleed product may be generated.

  The thickness of the pressure-sensitive adhesive tape of the present invention can be set to any appropriate thickness depending on the application. Typically, it is 15 μm to 450 μm.

  The haze value of the pressure-sensitive adhesive tape of the present invention is 13.5% to 80%, preferably 20% to 80%, more preferably 30% to 80%, and further preferably 35% to 75%. is there. If the haze value of an adhesive tape is such a range, the said adhesive tape has an external appearance suitable for an external appearance adjustment use.

B-1. Pressure-sensitive adhesive layer The thickness of the pressure-sensitive adhesive layer is preferably 1 μm to 300 μm, more preferably 4 μm to 100 μm, and particularly preferably 5 μm to 50 μm.

  Any appropriate value can be adopted as the haze value of the pressure-sensitive adhesive layer as long as the haze value of the pressure-sensitive adhesive tape of the present invention is 13.5% to 80%. Preferably, it is 1% to 80%, more preferably 10% to 60%. If the haze value of an adhesive layer is such a range, the adhesive tape which has an external appearance suitable for an external appearance adjustment use can be obtained.

  Arbitrary appropriate adhesive can be employ | adopted for the adhesive which comprises the said adhesive layer. Examples of the pressure sensitive adhesive include rubber pressure sensitive adhesive, acrylic pressure sensitive adhesive, and silicone pressure sensitive adhesive.

  A thermoplastic adhesive can also be used as the adhesive. Examples of the material constituting the thermoplastic pressure-sensitive adhesive include any appropriate styrene block copolymer and acrylic thermoplastic resin as the pressure-sensitive adhesive material.

  Specific examples of the styrenic block copolymer include styrenic AB type diblock copolymers such as styrene-ethylene-butylene copolymer (SEB); styrene-butadiene-styrene copolymer (SBS), and SBS. Hydrogenated product (styrene-ethylene-butylene-styrene copolymer (SEBS)), styrene-isoprene-styrene copolymer (SIS), hydrogenated product of SIS (styrene-ethylene-propylene-styrene copolymer (SEPS)) ), Styrene-ABA type triblock copolymer such as styrene-isobutylene-styrene copolymer (SIBS); styrene type ABAB type tetrablock copolymer such as styrene-butadiene-styrene-butadiene (SBSB); styrene-butadiene -Styrene-butadiene-styrene (SBSBS), etc. Styrenic ABABA type pentablock copolymer; Styrenic multiblock copolymer having AB repeating units higher than these; Hydrogenation of ethylenic double bond of styrene random copolymer such as styrene-butadiene rubber (SBR) And the like. Examples of commercially available products include “G1657” (styrene elastomer) manufactured by Kraton Polymer. The said copolymer may be used independently and may use 2 or more types together.

  The content of the styrene block structure in the styrenic block copolymer is preferably 5 to 40% by weight, more preferably 7 to 30% by weight, and particularly preferably 9 to 20% by weight. % By weight. When the content of the styrene block structure is less than 5% by weight, adhesive residue due to insufficient cohesive force of the pressure-sensitive adhesive layer is likely to occur. When there is more content rate of a styrene block structure than 40 weight%, an adhesive layer becomes hard and there exists a possibility that favorable adhesiveness cannot be obtained with respect to a rough surface.

  When the styrenic block copolymer has an ethylene-butylene block structure, the content of the structural unit derived from butylene in the ethylene-butylene block structure is preferably 50% by weight or more, more preferably 60% by weight or more, particularly Preferably it is 70 weight% or more, Most preferably, it is 70 weight%-90 weight%. When the content ratio of the structural unit derived from butylene is in such a range, a pressure-sensitive adhesive layer that is excellent in wettability and adhesiveness and can adhere well to a rough surface can be obtained.

  Examples of the acrylic thermoplastic resin include polymethyl methacrylate-polybutyl acrylate-polymethyl methacrylate copolymer (PMMA-PBA-PMMA copolymer); polybutyl acrylate having a carboxylic acid as a functional group. And the type of PMMA-functional group-containing PBA-PMMA copolymer. A commercially available product may be used as the acrylic thermoplastic resin. Specific examples of commercially available acrylic thermoplastic resins include trade name “NABSTAR” manufactured by Kaneka Corporation and trade name “LA polymer” manufactured by Kuraray Co., Ltd.

  The said adhesive layer can contain another component as needed. Examples of other components include olefin resins; silicone resins; liquid acrylic copolymers; polyethyleneimines; fatty acid amides; phosphate esters; The type, number and amount of other components contained in the pressure-sensitive adhesive layer can be appropriately set according to the purpose. Examples of the additive include tackifiers; softeners; anti-aging agents; hindered amine light stabilizers; ultraviolet absorbers; fillers or pigments such as calcium oxide, magnesium oxide, silica, zinc oxide, and titanium oxide; Is mentioned.

  The formulation of the tackifier is effective for improving the adhesive strength. The amount of the tackifier is appropriately determined to be any appropriate amount depending on the adherend in order to avoid the occurrence of the adhesive residue problem due to the decrease in cohesive force. Usually, it is 0-40 weight part with respect to 100 weight part of resin materials which form an adhesive, More preferably, it is 0-30 weight part, More preferably, it is 0-10 weight part.

  Examples of the tackifier include petroleum-based resins such as aliphatic copolymers, aromatic copolymers, aliphatic / aromatic copolymer systems and alicyclic copolymers, and coumarone-indene resins. Terpene resin, terpene phenol resin, rosin resin such as polymerized rosin, (alkyl) phenol resin, xylene resin or hydrogenated products thereof. A tackifier may be used independently and may use 2 or more types together.

  As the tackifier, hydrogenated tackifiers such as “Arcon P-125” manufactured by Arakawa Chemical Industries, Ltd. are preferable from the viewpoint of peelability and weather resistance. In addition, what is marketed as a blend with an olefin resin and a thermoplastic elastomer can also be used for a tackifier.

  The blending of the softener is effective for improving the adhesive strength. Examples of the softening agent include low molecular weight diene polymers, polyisobutylene, hydrogenated polyisoprene, hydrogenated polybutadiene, and derivatives thereof. Examples of the derivative include those having an OH group or a COOH group at one or both ends. Specific examples include hydrogenated polybutadiene diol, hydrogenated polybutadiene monool, hydrogenated polyisoprene diol, and hydrogenated polyisoprene monool. In order to further suppress the improvement in adhesion to the adherend, hydrogenated products of diene polymers such as hydrogenated polybutadiene and hydrogenated polyisoprene, olefinic softeners, and the like are preferable. Specific examples include “Kuraprene LIR-200” manufactured by Kuraray. These softeners may be used alone or in combination of two or more.

  The molecular weight of the softening agent can be appropriately set to any appropriate amount. If the molecular weight of the softening agent becomes too small, it may cause the material transfer from the adhesive layer to the adherend or heavy peeling, while if the molecular weight of the softening agent becomes too large, the effect of improving the adhesive strength may be caused. Since there exists a tendency to become scarce, the number average molecular weight of a softening agent becomes like this. Preferably it is 5000-100000, More preferably, it is 10000-50000.

  When using a softening agent, the addition amount can employ | adopt arbitrary appropriate amounts. If the amount of the softener added is too large, the adhesive residue tends to increase when exposed to high temperatures or outdoors. Therefore, preferably 100 parts by weight or less with respect to 100 parts by weight of the resin material forming the adhesive, More preferably, it is 20 weight part or less, More preferably, it is 10 weight part or less. When the addition amount of the softening agent exceeds 40 parts by weight with respect to 100 parts by weight of the resin material forming the pressure-sensitive adhesive, the adhesive residue becomes remarkable under outdoor exposure in a high temperature environment.

  The pressure-sensitive adhesive layer may be surface-treated on one side or both sides as necessary. Examples of the surface treatment include corona discharge treatment, ultraviolet irradiation treatment, flame treatment, plasma treatment, and sputter etching treatment.

B-2. Manufacturing method of an adhesive tape The adhesive tape of this invention can be obtained by arbitrary appropriate manufacturing methods. The pressure-sensitive adhesive tape of the present invention includes, for example, the substrate layer and the surface layer constituting the laminated film of the present invention, a method of co-extruding the pressure-sensitive adhesive layer (manufacturing method 1), and the surface layer of the laminated film. Method of hot-melt coating the pressure-sensitive adhesive on the side where the adhesive is not disposed (Manufacturing method 2), Organic solvent coating liquid or pressure-sensitive adhesive in which the pressure-sensitive adhesive is dissolved on the side where the surface layer of the laminated film is not disposed The method (manufacturing method 3) etc. which apply | coat the emulsion liquid which water-dispersed in water are mentioned. In addition, the laminated | multilayer film in the manufacturing methods 2 and 3 can be obtained by the method demonstrated by A-3 term.

  When manufacturing an adhesive tape by the said manufacturing method 1 or 2, the said thermoplastic adhesive is preferably used as an adhesive which comprises an adhesive layer.

  In the production method 1, the co-extrusion method is performed by using an extruder and a co-extrusion die for the base layer forming material, the surface layer forming material, and the pressure-sensitive adhesive layer forming material, respectively. It can be done according to this.

  When manufacturing an adhesive tape by the said manufacturing method 2 or 3, Preferably, an easily bonding process is given to the surface by which the adhesive is coated, ie, the surface where the said surface layer of the said laminated | multilayer film is not arrange | positioned. . Examples of the easy adhesion treatment include corona discharge treatment, itro treatment (silicic acid flame treatment), and anchor coat treatment.

  When manufacturing an adhesive tape by the said manufacturing method 3, as said adhesive which comprises the said adhesive layer, the said rubber adhesive, an acrylic adhesive, or a silicone adhesive is used preferably.

  When manufacturing an adhesive tape with the said manufacturing method 3, the said organic solvent can employ | adopt arbitrary appropriate things. Examples of the organic solvent include aromatic hydrocarbon solvents such as toluene and xylene; aliphatic carboxylic acid ester solvents such as ethyl acetate; aliphatic hydrocarbon solvents such as hexane, heptane and octane. The said organic solvent may be used independently and may use 2 or more types together.

  When manufacturing an adhesive tape by the said manufacturing method 3, the crosslinking agent may be included in the organic-solvent coating liquid. Examples of the crosslinking agent include an epoxy-based crosslinking agent, an isocyanate-based crosslinking agent, and an aziridine crosslinking agent.

  Arbitrary appropriate coating methods can be employ | adopted for the coating method in the case of manufacturing an adhesive tape by the said manufacturing method 3. FIG. Examples of the coating method include a method using a bar coater, a gravure coater, a spin coater, a roll coater, a knife coater, an applicator and the like.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited to these Examples at all. In addition, the test and evaluation method in an Example etc. are as follows. Moreover, a part means a weight part.

(1) Arithmetic average surface roughness Ra
After laminating the laminated film or the adhesive tape to the slide glass, the surface roughness of the surface layer is measured using an optical profiler NT9100 (manufactured by Veeco), Measurement Type: VSI (Infinite Scan), Objective: 2.5X. , FOV: 1.0X, Modulation Threshold: 0.1%, and measured at n = 3. After the measurement, data analysis was performed using Terms Remov: Tilt Only (Plane Fit) and Window Filtering: None to obtain the arithmetic average surface roughness Ra.
(2) Haze value The haze value was measured using a haze meter HM-150 (Murakami Color Research Laboratory Co., Ltd.). The haze was calculated by haze (%) = Td / Tt X 100 (Td: diffuse transmittance, Tt: total light transmittance) in accordance with JISK7136.

[Example 1]
The following compounds were prepared as a surface layer forming material, a base material layer forming material, and a smooth layer forming material.
Surface layer forming material: random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8; melt flow rate (MFR) = 0.8 (230 ° C., 2.16 kgf)) and low density polyethylene (Tosoh Corporation) ) Company: Petrocene 209; Melt flow rate (MFR) = 45 (190 ° C., 2.16 kgf)) 50 parts of mixture Base material layer forming material: Block polypropylene (manufactured by Sun Allomer: PF380A)
Smooth layer forming material: Low density polyethylene (Nippon Polyethylene: Novatec LD LC720)
Said material was shape | molded by T-die melt coextrusion, and the laminated film (1) provided with a surface layer, a base material layer, and a smooth layer in this order was obtained. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the smooth layer was 7 μm. Table 1 shows the evaluation results for the obtained laminated film (1).

[Example 2]
As a surface layer forming material, 50 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8; melt flow rate (MFR) = 0.8 (230 ° C., 2.16 kgf)) and low density polyethylene (Tosoh Corporation) ) Manufactured by: Petrocene 209; melt flow rate (MFR) = 45 (190 ° C., 2.16 kgf)), instead of a mixture of 50 parts, random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8; melt flow) Rate (MFR) = 0.8 (230 ° C., 2.16 kgf)) and low density polyethylene (Nippon Polyethylene Co., Ltd .: Novatec LD LJ803; Melt flow rate (MFR) = 22 (190 ° C., 2. 16 kgf)) A laminated film (2) as in Example 1 except that a mixture with 50 parts was used. It was obtained. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the smooth layer was 7 μm. Table 1 shows the evaluation results for the obtained laminated film (2).

[Example 3]
As a surface layer forming material, 50 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8; melt flow rate (MFR) = 0.8 (230 ° C., 2.16 kgf)) and low density polyethylene (Tosoh Corporation) ) Manufactured by: Petrocene 209; melt flow rate (MFR) = 45 (190 ° C., 2.16 kgf)), instead of a mixture of 50 parts, random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8; melt flow) Rate (MFR) = 0.8 (230 ° C., 2.16 kgf)) and low density polyethylene (manufactured by Tosoh Corporation: Petrocene 209; Melt flow rate (MFR) = 45 (190 ° C., 2.16 kgf) ) A laminated film (3) was obtained in the same manner as in Example 1 except that a mixture with 90 parts was used. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the smooth layer was 7 μm. Table 1 shows the evaluation results of the obtained laminated film (3).

[Example 4]
As a surface layer forming material, 50 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8; melt flow rate (MFR) = 0.8 (230 ° C., 2.16 kgf)) and low density polyethylene (Tosoh Corporation) ) Manufactured by: Petrocene 209; melt flow rate (MFR) = 45 (190 ° C., 2.16 kgf)), instead of a mixture of 50 parts, random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8; melt flow) 20 parts of rate (MFR) = 0.8 (230 ° C., 2.16 kgf)) and low-density polyethylene (manufactured by Tosoh Corporation: Petrocene 209; melt flow rate (MFR) = 45 (190 ° C., 2.16 kgf) ) A laminated film (4) was obtained in the same manner as in Example 1 except that a mixture with 80 parts was used. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the smooth layer was 7 μm. Table 1 shows the evaluation results of the obtained laminated film (4).

[Example 5]
As a surface layer forming material, 50 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8; melt flow rate (MFR) = 0.8 (230 ° C., 2.16 kgf)) and low density polyethylene (Tosoh Corporation) ) Manufactured by: Petrocene 209; melt flow rate (MFR) = 45 (190 ° C., 2.16 kgf)), instead of a mixture of 50 parts, random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8; melt flow) 30 parts of rate (MFR) = 0.8 (230 ° C., 2.16 kgf)) and low density polyethylene (manufactured by Tosoh Corporation: Petrocene 209; Melt flow rate (MFR) = 45 (190 ° C., 2.16 kgf) ) A laminated film (5) was obtained in the same manner as in Example 1 except that a mixture with 70 parts was used. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the smooth layer was 7 μm. Table 1 shows the evaluation results for the obtained laminated film (5).

[Example 6]
As a surface layer forming material, 50 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8; melt flow rate (MFR) = 0.8 (230 ° C., 2.16 kgf)) and low density polyethylene (Tosoh Corporation) ) Manufactured by: Petrocene 209; melt flow rate (MFR) = 45 (190 ° C., 2.16 kgf)), instead of a mixture of 50 parts, random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8; melt flow) 40 parts rate (MFR) = 0.8 (230 ° C., 2.16 kgf)) and low density polyethylene (manufactured by Tosoh Corporation: Petrocene 209; melt flow rate (MFR) = 45 (190 ° C., 2.16 kgf) ) A laminated film (6) was obtained in the same manner as in Example 1 except that a mixture with 60 parts was used. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the smooth layer was 7 μm. Table 1 shows the evaluation results of the obtained laminated film (6).

[Example 7]
As a surface layer forming material, 50 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8; melt flow rate (MFR) = 0.8 (230 ° C., 2.16 kgf)) and low density polyethylene (Tosoh Corporation) ) Manufactured by: Petrocene 209; melt flow rate (MFR) = 45 (190 ° C., 2.16 kgf)), instead of a mixture of 50 parts, random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8; melt flow) 70 parts of rate (MFR) = 0.8 (230 ° C., 2.16 kgf)) and low density polyethylene (manufactured by Tosoh Corporation: Petrocene 209; melt flow rate (MFR) = 45 (190 ° C., 2.16 kgf) ) A laminated film (7) was obtained in the same manner as in Example 1 except that a mixture with 30 parts was used. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the smooth layer was 7 μm. Table 1 shows the evaluation results for the obtained laminated film (7).

[Example 8]
As a surface layer forming material, 50 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8; melt flow rate (MFR) = 0.8 (230 ° C., 2.16 kgf)) and low density polyethylene (Tosoh Corporation) ) Manufactured by: Petrocene 209; melt flow rate (MFR) = 45 (190 ° C., 2.16 kgf)), instead of a mixture of 50 parts, random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8; melt flow) Rate (MFR) = 0.8 (230 ° C., 2.16 kgf)) and low density polyethylene (Nippon Polyethylene Co., Ltd .: Novatec LD LC720; Melt flow rate (MFR) = 9.4 (190 ° C., 2.16 kgf)) A laminated film (as in Example 1 except that a mixture with 50 parts was used. ) Was obtained. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the smooth layer was 7 μm. Table 1 shows the evaluation results for the obtained laminated film (8).

[Example 9]
As a surface layer forming material, 50 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8; melt flow rate (MFR) = 0.8 (230 ° C., 2.16 kgf)) and low density polyethylene (Tosoh Corporation) ) Manufactured by: Petrocene 209; melt flow rate (MFR) = 45 (190 ° C., 2.16 kgf)), instead of a mixture of 50 parts, random polypropylene (manufactured by Nippon Polypro Co., Ltd .: random PP WINTEC WSX02; melt 50 parts of flow rate (MFR) = 25 (230 ° C., 2.16 kgf)) and low density polyethylene (Sumitomo Chemical Co., Ltd .: Sumikasen F213P; Melt flow rate (MFR) = 1.5 (190 ° C., 2. 16 kgf)) A laminated film (as in Example 1 except that a mixture with 50 parts was used. ) Was obtained. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the smooth layer was 7 μm. Table 1 shows the evaluation results for the obtained laminated film (9).

[Example 10]
The following compounds were prepared as a surface layer forming material, a base material layer forming material, and an adhesive layer forming material.
Surface layer forming material: 50 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8), 50 parts of low density polyethylene (manufactured by Tosoh Corporation: Petrocene 209), and long-chain alkyl release agent (Acio Sangyo) Co., Ltd .: Aceoresin RA95HS (fully saponified polyvinyl octadecyl carbamate release agent)) 10 parts of mixture Base material layer forming material: Block polypropylene (manufactured by Sun Allomer: PF380A)
Adhesive layer forming material: 75 parts of styrene-ethylene-butylene-styrene block copolymer (SEBS) (manufactured by Kraton Polymer Co., Ltd .: G1657) and 25 parts of tackifier (manufactured by Arakawa Chemical Industries, Ltd .: Alcon P-125) The above material was molded by T-die melt coextrusion to obtain a pressure-sensitive adhesive tape (1) comprising a surface layer, a base material layer and a pressure-sensitive adhesive layer in this order. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the pressure-sensitive adhesive layer was 7 μm. Table 2 shows the evaluation results for the obtained adhesive tape (1).

[Example 11]
As the surface layer forming material, instead of using 50 parts of low density polyethylene (manufactured by Tosoh Corporation: Petrocene 209), 50 parts of low density polyethylene (manufactured by Nippon Polyethylene Corporation: Novatec LD LJ803), In the same manner as in Example 10, an adhesive tape (2) was obtained. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the pressure-sensitive adhesive layer was 7 μm. Table 2 shows the evaluation results of the obtained adhesive tape (2).

[Example 12]
Low-density polyethylene using 10 parts of random polypropylene (Nippon Polypro Corp .: Novatec PP EG8) instead of 50 parts of random polypropylene (Nippon Polypro Corp .: Novatec PP EG8) as the surface layer forming material. (Tosoh Co., Ltd .: Petrocene 209) Instead of 50 parts, low-density polyethylene (Tosoh Co., Ltd .: Petrocene 209) 90 parts was used in the same manner as in Example 10, except that adhesive tape ( 3) was obtained. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the pressure-sensitive adhesive layer was 7 μm. Table 2 shows the evaluation results of the obtained adhesive tape (3).

[Example 13]
As a surface layer forming material, instead of 50 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8), 20 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8) is used, and low density polyethylene is used. (Tosoh Co., Ltd .: Petrocene 209) Instead of 50 parts, low-density polyethylene (Tosoh Co., Ltd .: Petrocene 209) was used in the same manner as in Example 10 except that 80 parts were used. 4) was obtained. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the pressure-sensitive adhesive layer was 7 μm. Table 2 shows the evaluation results of the obtained adhesive tape (4).

[Example 14]
As a surface layer forming material, instead of 50 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8), 30 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8) is used, and low density polyethylene is used. (Tosoh Co., Ltd .: Petrocene 209) Instead of 50 parts, low-density polyethylene (Tosoh Co., Ltd .: Petrocene 209) 70 parts was used in the same manner as in Example 10 except that an adhesive tape ( 5) was obtained. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the pressure-sensitive adhesive layer was 7 μm. Table 2 shows the evaluation results for the obtained adhesive tape (5).

[Example 15]
As a surface layer forming material, instead of 50 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8), 40 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8) is used, and low density polyethylene is used. (Tosoh Co., Ltd .: Petrocene 209) Instead of 50 parts, low-density polyethylene (Tosoh Co., Ltd .: Petrocene 209) 60 parts was used in the same manner as in Example 10, except that an adhesive tape ( 6) was obtained. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the pressure-sensitive adhesive layer was 7 μm. Table 2 shows the evaluation results of the obtained adhesive tape (6).

[Example 16]
As a surface layer forming material, instead of 50 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8), 70 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8) is used, and low density polyethylene is used. (Tosoh Co., Ltd .: Petrocene 209) Instead of 50 parts, low-density polyethylene (Tosoh Co., Ltd .: Petrocene 209) 30 parts was used in the same manner as in Example 10, except that an adhesive tape ( 7) was obtained. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the pressure-sensitive adhesive layer was 7 μm. Table 2 shows the evaluation results of the obtained adhesive tape (7).

[Example 17]
As surface layer forming material, instead of 50 parts of low density polyethylene (manufactured by Tosoh Corporation: Petrocene 209), 50 parts of low density polyethylene (manufactured by Nippon Polyethylene Corporation: Novatec LD LC720) was used, In the same manner as in Example 10, an adhesive tape (8) was obtained. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the pressure-sensitive adhesive layer was 7 μm. Table 2 shows the evaluation results of the obtained adhesive tape (8).

[Example 18]
As the surface layer forming material, 50 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8), 50 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: random PP WINTEC WSX02) are used, and the density is low. In the same manner as in Example 10 except that 50 parts of low density polyethylene (Sumitomo Chemical Co., Ltd .: Sumikasen F213P) was used instead of 50 parts of polyethylene (Tosoh Corporation: Petrocene 209), adhesive Tape (9) was obtained. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the pressure-sensitive adhesive layer was 7 μm. Table 2 shows the evaluation results for the obtained adhesive tape (9).

[Comparative Example 1]
As a surface layer forming material, 50 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8; melt flow rate (MFR) = 0.8 (230 ° C., 2.16 kgf)) and low density polyethylene (Tosoh Corporation) ) Manufactured by: Petrocene 209; melt flow rate (MFR) = 45 (190 ° C., 2.16 kgf)), instead of a mixture with 50 parts, random polypropylene (manufactured by Sun Allomer Co., Ltd .: PC630A; melt flow rate (MFR) ) = 7.5 (230 ° C., 2.16 kgf)) and 50 parts low density polyethylene (Nippon Polyethylene Co., Ltd .: Novatec LD LC720; Melt flow rate (MFR) = 9.4 (190 ° C., 2.16 kgf) )) A laminated film (C1) was prepared in the same manner as in Example 1 except that a mixture with 50 parts was used. It was. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the smooth layer was 7 μm. Table 1 shows the evaluation results for the obtained laminated film (C1).

[Comparative Example 2]
As a surface layer forming material, 50 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8; melt flow rate (MFR) = 0.8 (230 ° C., 2.16 kgf)) and low density polyethylene (Tosoh Corporation) ) Manufactured by: Petrocene 209; melt flow rate (MFR) = 45 (190 ° C., 2.16 kgf)), instead of a mixture of 50 parts, random polypropylene (manufactured by Nippon Polypro Co., Ltd .: random PP WINTEC WSX02; melt 50 parts of flow rate (MFR) = 25 (230 ° C., 2.16 kgf)) and low density polyethylene (manufactured by Nippon Polyethylene Co., Ltd .: Novatec LD LC720; Melt flow rate (MFR) = 9.4 (190 ° C., 2 .16 kgf)) In the same manner as in Example 1 except that a mixture with 50 parts was used. A layer film (C2) was obtained. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the smooth layer was 7 μm. Table 1 shows the evaluation results of the obtained laminated film (C2).

[Comparative Example 3]
As a surface layer forming material, 50 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8; melt flow rate (MFR) = 0.8 (230 ° C., 2.16 kgf)) and low density polyethylene (Tosoh Corporation) ) Manufactured by: Petrocene 209; melt flow rate (MFR) = 45 (190 ° C., 2.16 kgf)), instead of a mixture of 50 parts, random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8; melt flow) A laminated film (C3) was obtained in the same manner as in Example 1 except that 100 parts of rate (MFR) = 0.8 (230 ° C., 2.16 kgf)) were used. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the smooth layer was 7 μm. The evaluation results for the obtained laminated film (C3) are shown in Table 1.

[Comparative Example 4]
As a surface layer forming material, 50 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8; melt flow rate (MFR) = 0.8 (230 ° C., 2.16 kgf)) and low density polyethylene (Tosoh Corporation) ): Petrocene 209; Melt flow rate (MFR) = 45 (190 ° C., 2.16 kgf)) In place of the mixture with 50 parts, low-density polyethylene (manufactured by Tosoh Corporation: Petrocene 209; melt flow rate) A laminated film (C4) was obtained in the same manner as in Example 1 except that 100 parts of (MFR) = 45 (190 ° C., 2.16 kgf)) was used. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the smooth layer was 7 μm. Table 1 shows the evaluation results of the obtained laminated film (C4).

[Comparative Example 5]
Instead of 50 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8) as a surface layer forming material, 50 parts of random polypropylene (manufactured by Sun Allomer Co., Ltd .: PC630A) is used, and low density polyethylene (Tosoh ( Co., Ltd .: Petrocene 209) The adhesive tape (C1) was obtained in the same manner as in Example 10 except that 50 parts of low density polyethylene (Nippon Polyethylene Co., Ltd .: Novatec LD LC720) was used instead of 50 parts. It was. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the pressure-sensitive adhesive layer was 7 μm. Table 2 shows the evaluation results of the obtained adhesive tape (C1).

[Comparative Example 6]
As the surface layer forming material, 50 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8), 50 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: random PP WINTEC WSX02) are used, and the density is low. In the same manner as in Example 10, except that 50 parts of low density polyethylene (Nippon Polyethylene: Novatec LD LC720) was used instead of 50 parts of polyethylene (manufactured by Tosoh Corporation: Petrocene 209), an adhesive tape ( C2) was obtained. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the pressure-sensitive adhesive layer was 7 μm. Table 2 shows the evaluation results for the obtained adhesive tape (C2).

[Comparative Example 7]
Instead of 50 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8) and 50 parts of low density polyethylene (manufactured by Tosoh Corporation: Petrocene 209) as the surface layer forming material, random polypropylene (Nippon Polypro ( Co., Ltd .: Novatec PP EG8) An adhesive tape (C3) was obtained in the same manner as in Example 10 except that 100 parts were used. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the pressure-sensitive adhesive layer was 7 μm. Table 2 shows the evaluation results for the obtained adhesive tape (C3).

[Comparative Example 8]
Instead of 50 parts of random polypropylene (manufactured by Nippon Polypro Co., Ltd .: Novatec PP EG8) and 50 parts of low density polyethylene (manufactured by Tosoh Corporation: Petrocene 209) as the surface layer forming material, low density polyethylene (Tosoh ( Co., Ltd .: Petrocene 209) An adhesive tape (C4) was obtained in the same manner as in Example 10 except that 100 parts were used. The thickness of the surface layer was 2 μm, the thickness of the base material layer was 38 μm, and the thickness of the pressure-sensitive adhesive layer was 7 μm. Table 2 shows the evaluation results of the obtained adhesive tape (C4).

  As is clear from Tables 1 and 2, the laminated film and the pressure-sensitive adhesive tape of the present invention can control the haze value and the surface roughness within an appropriate range only by adjusting the composition of the surface layer. Moreover, since the surface layer is very thin, it does not affect the mechanical properties of the entire laminated film or adhesive tape.

  The laminated film and pressure-sensitive adhesive tape of the present invention can be widely used in applications where design properties are required, for example, protective applications, appearance adjustment applications, decoration applications, label applications, etc. in the production of electronic parts, structures, and automobiles. .

DESCRIPTION OF SYMBOLS 1 Base material layer 2 Surface layer 10 Laminated film 20 Adhesive layer 100 Adhesive tape

Claims (5)

A pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer on one side of a laminated film having a base material layer and a surface layer,
The base material layer includes a thermoplastic resin;
The surface layer comprises polyethylene and a propylene-based polymer;
The weight ratio of the polyethylene to the propylene polymer is polyethylene: propylene polymer = 10: 90 to 90:10,
The melt flow rate of the polyethylene is 8 g / 10 min to 100 g / 10 min,
The melt flow rate of the propylene-based polymer is 0.1 g / 10 min to 7 g / 10 min,
The arithmetic average surface roughness Ra of the surface layer is 0.5 μm to 2.0 μm,
The haze value of the adhesive tape is 20% to 80%,
Pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer is a thermoplastic adhesive, the material constituting the thermoplastic adhesive Ru der styrenic block copolymer or thermoplastic acrylic resin,
Adhesive tape . The pressure-sensitive adhesive tape according to claim 1 , wherein the surface layer has a thickness of 2 μm to 10 μm. The pressure-sensitive adhesive tape according to claim 1 or 2 , wherein the surface layer has two or more melting temperatures Tm in differential scanning calorimetry. The pressure-sensitive adhesive tape according to any one of claims 1 to 3 , wherein the surface layer has a long-chain alkyl release agent. The pressure-sensitive adhesive tape according to any one of claims 1 to 4, wherein a difference between a melting point of the polyethylene and a melting point of the polypropylene-based polymer is 5 ° C to 65 ° C.

Images