JP2008183802A - Contamination resistant adhesive film and contamination resistant structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an adhesive film or a structure which enables the easy and sufficient removal of contamination by scribbling, also easily and sufficiently remove pasted paper on it. <P>SOLUTION: The contamination resistant adhesive film is provided, which has a surface clear layer having microstructures on it, a base film layer provided on a surface opposed to the surface of the surface clear layer, and an adhesive layer provided on the surface of the base film layer opposed to the surface clear layer, wherein the surface clear layer is formed of a resin having a surface free energy of 32 mJ/m<SP>2</SP>or smaller, with the microstructures incorporating regularly arranged tapered projections regularly arranged on the surface of the surface clear layer with a prescribed repeating pattern, and an arrangement density of 500-7,000 pieces/cm<SP>2</SP>and a height of 5-80 μm. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a stain-resistant adhesive film or a stain-resistant structure.

  In recent years, the scenic beauty of streets has been impaired due to graffiti on outdoor advertising items such as store shutters and billboards on the streets, or contamination by stickers such as advertisements and bills, etc. ) Has been reduced in value. These phenomena are one of the social problems, and there is a demand for prevention of contamination by graffiti and sticking or a method for easily removing contamination caused by these.

  Conventionally, a coating with silicone oil or wax added to the graffiti prevention performance is applied to the adherend, and a silicone-based resin paint or fluororesin-based paint is applied to form a pollution-preventing coating film. Has been proposed. Moreover, the sheet | seat which has a paper-sticking prevention or removal performance by forming an uneven | corrugated-shaped coating film using bead containing resin, or forming a surface unevenness | corrugation by embossing has been proposed.

  Specifically, a bead-containing resin layer is formed on a base film, and a releasable resin layer is further formed on the embossed surface of the thermoplastic resin sheet. An uneven top coating film is formed using an adhesive sheet for preventing sticking (see, for example, Patent Document 2) in which a cured resin layer is provided and an adhesive layer and a release layer are sequentially provided on the other surface, and an undercoat paint. Discloses a contamination prevention method (for example, see Patent Document 3) in which a clear resin containing a moisture-curing polysiloxane resin is formed.

  In addition, graffiti ink removability and sticker peelable paint film comprising a primer coat resin primer, intermediate coat moisture curable silicone resin, and top coat room temperature cure silicone resin clear are disclosed. The removal performance is achieved by wiping the graffiti with a lacquer thinner (see, for example, Patent Document 4).

  Furthermore, an anti-slip sheet is disclosed in which a plurality of tapered protrusions made of a resin composition are regularly arranged (see, for example, Patent Document 5 and Patent Document 6).

However, these conventional techniques do not disclose an adhesive film or a structure that has both the ability to easily and sufficiently remove contamination such as graffiti and the ability to easily and sufficiently remove the sticker.
Japanese Utility Model Publication No. 63-16120 Japanese Patent Laid-Open No. 10-121022 Japanese Patent Laid-Open No. 10-216619 JP 2004-167396 A Japanese Patent Laid-Open No. 10-502305 JP 2003-39582 A

  An object of this invention is to provide the adhesive film or structure which can remove the contamination by graffiti easily and fully, and can remove a sticker easily and fully.

That is, the present invention is provided on the surface clear layer having a fine structure on the surface, the base film layer provided on the surface facing the surface of the surface clear layer, and the surface of the base film layer facing the surface clear layer. The surface clear layer is made of a resin having a surface free energy of 32 mJ / m ² or less, and the fine structure has tapered protrusions regularly arranged on the surface. The tapered protrusions are regularly arranged on the surface of the surface clear layer with a predetermined repeating pattern, the arrangement density of the tapered protrusions is 500 to 7000 pieces / cm ² , and the height of the tapered protrusions is 5 It provides a stain-resistant adhesive film that is ˜80 μm.

Further, the present invention includes a taper protrusion made of a resin having a surface free energy of 32 mJ / m ² or less, having a fine structure on the surface, and the fine structure regularly arranged on the surface, wherein the taper protrusion is predetermined. The contamination-resistant structure is provided on the surface with a repetitive pattern of the above, the arrangement density of the tapered protrusions is 500 to 7000 pieces / cm ² , and the height of the tapered protrusions is 5 to 80 μm. is there.

  With the stain-resistant adhesive film or stain-resistant structure of the present invention, two performances can be achieved simultaneously: graffiti contamination and easy removal of stickers. And by applying these films or structures to concrete objects or painted surfaces such as utility poles, walls, tonnell, or store shutters, graffiti on these objects by lacquer spray or oily magic etc. It can be easily removed, and it is possible to easily peel off stickers such as advertisements and leaflets stuck on these objects without leaving traces.

The surface clear layer of the present invention is made of a resin having a surface free energy of 32 mJ / m ² or less.
Surface free energy is the excess free energy required for a molecule on a liquid or solid surface to break off some of its intermolecular attractive forces. Unlike the molecules on the surface, the surface molecules are not surrounded by other molecules, so excessive free energy is required.

In the present invention, the surface free energy value is preferably 32 mJ / m ² or less.

Examples of the resin having a surface free energy of 32 mJ / m ² or less include a resin having one or more polymers selected from the group consisting of a silicone polymer, a fluorine polymer, an acrylic polymer, and a urethane polymer as an essential component. be able to.

  Specific examples of the polymer include Clearvale (registered trademark, manufactured by Kikusui Chemical Co., Ltd.), Magic Art (registered trademark, manufactured by Dainippon Paint Co., Ltd.), Regigard (trademark) FA Renew (Dainippon Paint Co., Ltd.). ), Papyres (registered trademark) 100 Clear (manufactured by NATCO), Fressera (registered trademark) D (manufactured by Matsushita Electric Works), Sylvia (registered trademark) SP Yogore Guard (manufactured by Nippon Special Paint Co., Ltd.), KS ( Registered trademark) Ceraton (manufactured by Kikusui Chemical Co., Ltd.) and Amix Cone (registered trademark, manufactured by Atomics Co., Ltd.).

  In addition to the polymer as a main agent, conventionally known additives such as a surface modifier, a curing agent, a surfactant, hard beads, or a crosslinking agent can be appropriately added to the resin.

  The surface clear layer of the present invention has a fine structure on its surface. The fine structure is composed of regularly arranged tapered protrusions.

  The tapered protrusions are so-called pattern arrangement protrusions that are regularly arranged on the support surface with a predetermined repeating pattern, and each of the tapered protrusions is surrounded by a plurality of grooves intersecting each other. The predetermined repeating pattern needs to be regular, but it does not matter whether the protrusions are arranged continuously or discontinuously. Here, “arranged continuously” means that all the bottoms of the protrusions are in contact with the bottoms of the adjacent protrusions. Further, “discontinuously arranged” means that any one of the bottoms of the protrusions is not in contact with the bottom of the adjacent protrusions, that is, there is a horizontal plane portion on the surface of the surface clear layer. means.

  The shape of the tapered protrusion is not particularly limited as long as each protrusion has a uniform shape and has a sharp tip. Examples of the tapered protrusion shape include a substantially pyramid or a cone, a triangular pyramid, a quadrangular pyramid, or a cone.

The arrangement density of the tapered protrusions is the number (units / cm ² ) per unit area of the tip protrusions of the surface fine structure of the surface clear layer, and can be measured using an optical microscope. In measurement, for example, the length of each side can be used when the bottom surface of the protrusion is a square, and the diameter can be used when the projection is circular. The arrangement density is preferably from 500 to 7000 pieces / cm ^2, 600-7,000 pieces / cm ^2, more preferably from 600 to 3000 pieces / cm ² or 1000 to 3000 pieces / cm ^2,.

  The tapered protrusion can be applied to the surface of the surface clear layer by embossing as will be described later.

  The height of the tapered protrusion is the shortest distance from the bottom surface of the protrusion to the most distal portion of the farthest tip protrusion (see FIG. 2), and depends on the embossing depth of the embossing roll surface used during embossing. The height of the tapered protrusion is preferably 1 to 80 μm, more preferably 5 to 80 μm, 5 to 30 μm, 10 to 80 μm, or 10 to 30 μm.

  The thickness of the surface clear layer of the present invention is the shortest distance from the surface where the surface clear layer is in contact with the base film layer to the most distal portion of the tapered protrusion. The thickness is not particularly limited as long as the effect of the present invention can be exhibited, and it can be manufactured and used from a relatively thin to a relatively thick one. In the adhesive film of the present invention, usually 5 to 200 μm, Or it is 10-100 micrometers, and in the structure of this invention, it is 5-2500 micrometers normally.

  Since the surface clear layer of the present invention has a non-adhesiveness (adhesive strength) of 1 N / 25 mm or less, it has an effective paper-proofing performance. The non-adhesiveness of 1 N / 25 mm or less is a value at which the patch naturally peels off by wind or the like.

  The base film layer of the present invention is not particularly limited as long as the surface clear layer of the present invention can be formed on at least one surface thereof and an adhesive layer can be formed on the surface opposite to the surface clear layer. Such films include, for example, polyesters such as polyethylene terephthalate and polyethylene naphthalate, polyetheresters composed of polyoxyalkylene glycol and the polyester, polyolefins, vinyl chloride, urethane, or (meth) acrylic polymers. A film can be mentioned. In this specification, “(meth) acryl” means acryl or methacryl.

  Although the thickness of the said base film layer is not specifically limited, Usually, it is the range of 5-250 micrometers, or 10-300 micrometers.

  The adhesive of the adhesive layer of the present invention is not particularly limited, but is usually a pressure-sensitive adhesive containing a tacky polymer. As such a pressure-sensitive adhesive layer, for example, a single-layer pressure-sensitive adhesive film containing an adhesive polymer or a double-sided adhesive sheet having two pressure-sensitive adhesive layers is preferably used.

  The adhesive layer can be formed from, for example, a coating film of an adhesive containing an adhesive polymer. A preferred adhesive contains an adhesive polymer and a crosslinking agent that crosslinks the adhesive polymer. In the present specification, the adhesive polymer is a polymer that exhibits adhesiveness at room temperature (about 25 ° C.). As the adhesive polymer, acrylic polymer, polyurethane, polyolefin, polyester and the like can be used.

  Although the thickness of the said adhesive bond layer is not specifically limited, Usually, it is the range of 5-500 micrometers, or 10-300 micrometers.

  In the stain-resistant adhesive film of the present invention, a liner (release paper) can be provided on the opposite side of the adhesive layer from the base film layer. Such a liner may be one generally used in the field such as an adhesive tape, and is not limited to a specific member. Suitable liners for use in the present invention include, for example, paper, for example, plastic materials such as polyethylene, polypropylene, polyester, or cellulose acetate, or paper coated with or laminated with such plastic materials and others Material. These liners may be used as they are, but are preferably used after being treated with a silicone treatment or other methods to improve the release characteristics. Further, the thickness of the liner is not particularly limited, but usually about 25 to 500 μm or about 50 to 200 μm is preferable.

  In the production of the surface clear layer of the present invention, the tapered protrusions can be formed by a conventionally known method.

  For example, a finely structured liner (surface clear layer precursor) having a raised portion by embossing is prepared, and after the resin composition layer is applied on the liner, the liner is peeled to form a surface clear layer. There is a way. Specific examples of the method are as described in Examples.

  Or the sheet | seat (surface clear layer precursor) which consists of a resin composition in which the taper protrusion is not formed in the surface is prepared, the surface of the said sheet is embossed, and it is set as the surface clear layer which has a taper protrusion on the surface. There is a way.

  The embossing is usually performed by sandwiching a surface clear layer precursor between a processing roll and a backup roll and transferring the roughness of the processing roll surface. That is, a processing roll having a predetermined concavo-convex shape and roughness corresponding to the concavo-convex shape and roughness to be imparted to the surface clear layer surface is pressed against the surface clear layer precursor surface and embossed. The embossing is preferably performed while heating. The heating temperature is usually 120 to 270 ° C, preferably 130 to 260 ° C. The pressure is usually in the range of about 0.4 to 1.0 MPa.

  It is preferable that the processing roll is usually a steel roll whose surface is metal-plated (such as chromium), and the surface roughness is precisely controlled.

  The backup roll may be made of the same material as the processing roll, but usually uses a soft roll formed by wrapping a surface covering material made of a flexible material such as rubber or cotton around the surface of a metal roll. .

  The other processing conditions are in accordance with a general method for embossing the surface of the protective layer of a conventional sheet. When the resin composition constituting the surface clear layer precursor contains a thermosetting resin such as polyester, it comprises a support and a thermoplastic resin layer in close contact with the back surface in order to facilitate protrusion formation by embossing. It is preferable to emboss the surface clear layer precursor using a cushion material. The thickness of the cushion material is usually 25 to 500 μm.

  The stain-resistant adhesive film of the present invention can be produced by laminating the above-described components, that is, the surface clear layer, the base film layer, and the adhesive layer by a conventionally known method.

  For example, after an adhesive layer is formed on a release liner and a base film layer is formed on another release liner, they are bonded together by dry laminating or the like, and after removing the release liner of the base film layer, separately prepared A method of laminating a surface clear layer, or by forming a base film layer on a surface clear layer formed on a liner having a surface microstructure, and by separately laminating an adhesive layer formed on a release liner It is a method of pasting together.

  The contamination-resistant structure of the present invention is composed of the surface clear layer. The surface clear layer is as described above.

  Such a stain-resistant structure is used by (1) adhering directly to various objects with an adhesive or the like, and (2) providing an appropriate adhesive layer on the surface opposite to the surface having the fine structure of the structure. It is possible to use it by attaching it to various objects after installation, or (3) using it in various forms such as attaching to the object by a method other than adhesion or adhesion, or covering the object. is there.

  As an example of the use of (1) above, the structure of the present invention is applied to a concrete surface or painted surface such as a utility pole, wall, tonnell, or store shutter by using various adhesives / adhesives suitable for conventionally used resins. For example, it can be applied to an object such as

  In the case of the above (2), the adhesive layer provided on the surface facing the surface of the structure of the present invention may be of any composition, thickness, or any other properties as long as it is conventionally known. If necessary, a conventionally known release liner can be provided on the side of the adhesive layer opposite to the surface clear layer.

  Examples of use of the above (3) include the structure of the present invention alone, or further, by attaching an appropriate support to the surface opposite to the surface having the fine structure of the structure, and covering a utility pole or the like. Use bolts or scissors on objects that are difficult to fix with adhesives or adhesives, such as concrete surfaces such as walls, tonnell, or store shutters, or painted surfaces, such as bolts, scissors, etc. It is conceivable to use it by fixing it with a fastener.

(Manufacture of clear resin)
Resin 1: Clearvale (registered trademark, two-component silicone resin, manufactured by Kikusui Chemical Co., Ltd.) is used as the main material, and an isocyanate-based resin curing agent (manufactured by Kikusui Chemical Co., Ltd.) is used as the curing agent. It mix | blended so that it might become material / hardening agent = 4/1.
Resin 2: Magic Art (registered trademark, two-component silicone-modified fluororesin paint, manufactured by Dainippon Paint Co., Ltd.) is used as the main material, and an isocyanate resin curing agent (produced by Dainippon Paint Co., Ltd.) is used as the curing agent. It mix | blended so that it might become main material / hardener = 4/1 by ratio.
Resin 3: Lumiflon (registered trademark) LF910LM (two-component fluororesin paint solid content 66%, manufactured by Asahi Glass Co., Ltd.) as the main material, and Sumijoule (registered trademark) N3300 (manufactured by Sumitomo Bayer Urethane Co., Ltd.) as the curing agent Used and blended so that the weight ratio of the main material / curing agent was 4.7 / 1.

(Measurement of surface free energy)
Various resins were coated on the liner by knife coating so that the thickness after drying was 10 μm, and then the dried resin was peeled from the liner to obtain a sample. As the liner, a paper-based double-sided polyethylene laminate release paper (manufactured by 3M) was used.

  The surface free energy of each sample was measured using a fully automatic contact angle meter CA-W150 manufactured by Kyowa Interface Science Co., Ltd. and surface free energy analysis software (surface free energy analysis add-in software FAMAS). As the probe liquid, water, ethylene glycol, and n-hexadecane were used and analyzed using the theory of Kitazaki and Hara. The results are shown in Table 1.

(Measurement of protrusion arrangement density)
Using an optical microscope, the length of each side was measured when the bottom surface of the protrusion was square, and the diameter was measured when the projection was circular. The results are shown in Table 1.

(Measurement of easy cleaning)
Easy cleanability is an index representing graffiti removal performance, and was expressed by evaluating the performance of oil-based marking pens and lacquer sprays. Various test pieces were attached to a melamine baked paint board manufactured by Partec Co., Ltd. to obtain test pieces. The surface of the test piece was scribbled with an oil-based marking pen and a lacquer spray, allowed to stand at room temperature for 1 day, and then visually observed for the state of the coating film when wiped with a dry waste cloth. When it was able to be removed completely, it was evaluated as ○, and when graffiti remained, it was evaluated as ×. Two types of oil-based marking pens, magic ink (registered trademark) black (manufactured by Teraoka Chemical Co., Ltd.) and piece marker red (manufactured by Mitsubishi Pencil Co., Ltd.), were used. As the lacquer spray, hobby spray red (manufactured by Konan Shoji Co., Ltd.) was used. The results are shown in Table 1.

(Measurement of non-stickiness)
Non-adhesiveness is an index representing paper-sticking prevention performance, and was expressed by evaluating adhesive tape adhesive strength to a test piece. The test piece was affixed on a melamine baked paint board manufactured by Partex to obtain a test piece. A masking tape (Sumitomo 3M Co., Ltd. Scotch (registered trademark) paper masking tape No. 250) was attached to the affixing test piece in a 20 ° C. environment. Pasting was performed in accordance with JIS Z 0237 8.2.3. After leaving at the same temperature for 48 hours, 180 ° peel strength was measured with Tensilon. The results are shown in Table 1.

Examples 1-3, Comparative Examples 1-5 and 7
The embossing roll was cut with a diamond tool or laser-processed, and the following seven patterns of rolls having different pitch, depth, and width at the top of the groove, the bottom of the groove, and the bottom angle were created. The relationship between the seven patterns of rolls (A to G) and the examples and comparative examples using these rolls is as follows.
Roll A: Example 1 and Comparative Example 7
Roll B: Examples 2-3
Roll C: Comparative Example 1
Roll D: Comparative Example 2
Roll E: Comparative Example 3
Roll F: Comparative Example 4
Roll G: Comparative Example 5

  A release liner having a silicone coating on polyethylene of polyethylene-processed paper was embossed between a heated rubber roll and each of the embossing rolls to produce a microstructured liner having raised portions. Polyethylene processed paper is available from Rexam or Inccoat. The fine structure on the obtained liner reflects the shape of the surface of each roll (inverted shape), and has the arrangement density and protrusion height shown in Table 1.

  Then, after apply | coating each clear resin solution on the obtained liner, it dried at 95 degreeC for 20 minute (s), and formed the surface clear layer. The thickness of each surface clear layer obtained is “the height of the protrusion on each surface clear layer (see FIG. 2)” and “the thickness of the entire surface clear layer excluding the protrusion (see FIG. 2; 30 μm). The total value.

  An acrylic polyol resin (Desmophen® (registered trademark) A365, manufactured by Sumitomo Bayer Urethane Co., Ltd.) and an HDI type isocyanate resin (Sumijoule (registered trademark) N3300, manufactured by Sumika Bayer Urethane Co., Ltd.) have an NCO / OH equivalent ratio of 1.0. The base film layer resin solution obtained by mixing was applied to the surface clear layer by knife coating and dried at 95 ° C. for 20 minutes to form a 30 μm thick transparent base film layer.

  Furthermore, an acrylic pressure-sensitive adhesive comprising an isooctyl acrylate / methyl acrylate / acrylic ester copolymer and a composition ratio of 70: 22.5: 7.5 (weight ratio) was prepared. Solvent is ethyl acetate, solid content 40%. A pressure-sensitive adhesive composition of acrylic pressure-sensitive adhesive / aziridine-based crosslinking agent (1,1′-isophthaloyl-bis (2-methylaziridine)) = 100: 0.21 (solid content ratio) was prepared, and a paper base was prepared by knife coating. It coated so that the thickness after drying might be set to 30 micrometers on double-sided polyethylene laminate release paper. It was heated at 90 ° C. for 5 minutes, dried and crosslinked to obtain an adhesive layer.

  The obtained adhesive layer and the transparent base film were subjected to dry lamination to obtain an adhesive film.

Comparative Example 6
An acrylic polyol resin (Desmophen (registered trademark) A365, manufactured by Sumitomo Bayer Urethane Co., Ltd.) and an HDI type isocyanate resin (Sumijoule (registered trademark) N3300, manufactured by Sumika Bayer Urethane Co., Ltd.) are used in an NCO / OH equivalent ratio = 1.0. To obtain a base film layer resin solution. The obtained resin solution was applied to a 50 μm release-treated polyester film from a knife coat and dried at 95 ° C. for 20 minutes to form a transparent base film layer having a thickness of 30 μm.

  Plastic beads (Tuffic (trademark) AR650L, manufactured by Toyobo Co., Ltd.) were added to the resin 1 shown in Table 1 so that the solid content ratio was 10% by weight to obtain a clear layer resin solution. It was applied onto the transparent base film layer by knife coating, dried at 95 ° C. for 20 minutes, and crosslinked. Further, an acrylic pressure-sensitive adhesive composition was formed in the same manner as in Example 1, and dry-laminated with the base film layer on the surface from which the release-treated polyester film was peeled to obtain an adhesive film.

Reference example 1
An adhesive film was obtained in the same manner as in Example 1 except that the fine structure liner was changed to a paper-based double-sided polyethylene laminate release paper (manufactured by 3M).

It is a typical structure of the stain-resistant adhesive film of the present invention. It is the typical structure of the surface clear layer of this invention, or a contamination-resistant structure. It is sectional drawing of the surface clear layer of this invention which has a continuous front-end | tip protrusion, or a contamination-resistant structure surface. It is sectional drawing of the surface clear layer of this invention which has a discontinuous front-end | tip protrusion, or the surface of a contamination-resistant structure.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Surface clear layer 2 Base film layer 3 Adhesive layer 4 Release paper 5 Protrusion height 6 Thickness of the part remove | excluding protrusion from the whole surface clear layer 7 Thickness of surface clear layer

Claims (5)

A surface clear layer having a fine structure on the surface, a base film layer provided on a surface facing the surface of the surface clear layer, and an adhesive layer provided on a surface of the base film layer facing the surface clear layer The surface clear layer comprises a resin having a surface free energy of 32 mJ / m ² or less, and the fine structure includes tapered protrusions regularly arranged on the surface, and the tapered protrusion has Is regularly arranged on the surface of the surface clear layer with a predetermined repeating pattern, the arrangement density of the tapered protrusions is 500 to 7000 pieces / cm ² , and the height of the tapered protrusions is 5 to 80 μm. Contamination adhesive film.   The contamination-resistant adhesive film according to claim 1, wherein the shape of the tapered protrusion is a substantially pyramid or a substantially cone. Arrangement density of the tapered projections, stain resistance adhesive film according to claim 1 or 2 which is 600 to 3000 pieces / cm ^2.   The contamination-resistant adhesive film according to any one of claims 1 to 3, wherein the tapered protrusion has a height of 10 to 30 µm. The surface free energy is made of a resin having a surface free energy of 32 mJ / m ² or less, has a fine structure on the surface, the fine structure is provided with tapered protrusions regularly arranged on the surface, and the tapered protrusions have a predetermined repeating pattern. A contamination-resistant structure which is disposed on the surface, has an arrangement density of the tapered protrusions of 500 to 7000 pieces / cm ² , and a height of the tapered protrusions of 5 to 80 μm.

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