JP5127017B2 - Antifouling overlamination sheet - Google Patents

Description

  The present invention relates to an antifouling overflow sheet, and more particularly to an antifouling overflow sheet capable of preventing contamination of signs such as signs, posters, road signs or construction signs.

  In recent years, signboards, posters, banners, banners, road signs, guide signs, construction signs, display sheets, display boards, etc. (hereinafter collectively referred to as display sheets) have been used. It is necessary to maintain a clean and clean state. If dirt is attached, it may cause discomfort to the eyes, sometimes make it difficult to read the display items, and may damage the image of the product or the business.

  However, since signs are often installed outdoors, they are easily contaminated with dust and the like, and frequent cleaning and replacement have been required to maintain a clear state.

  As a method for reducing the contamination of outdoor equipment products, conventionally, a water-repellent synthetic resin or an antifouling agent containing a fluorine-based material or a silicon-based material for increasing the water repellency has been applied. However, those utilizing water repellency have the problem that when rainwater or the like adheres, water droplets are formed, and when dried as they are, contaminants adhere to the dry marks and form dot-like stains.

  In recent years, as a method for reducing contamination, it has been proposed to make the surface hydrophilic (Patent Documents 1, 2, and 3). This is because, when the surface is made hydrophilic, hydrophilic pollutants adhere, but they are easily removed by natural purification action such as rain, while lipophilic pollutants that are hard to be washed away are difficult to adhere. To do.

  However, there is no proposal for preventing contamination of the display sheet and maintaining the display in a clear state for a long time. In addition, the method of applying the antifouling agent to make the surface of the display sheet hydrophilic has a problem that the display sheet itself needs to be replaced when the antifouling effect is lowered with time.

For this reason, the display sheet excellent in the pollution prevention effect was obtained, and when pollution prevention fell, development of the pollution prevention technique which can be reproduced | regenerated was requested | required.
JP-A-11-267585 JP 2004-142161 A JP 2003-55480 A

  The present invention has an effect of preventing contamination over a long period of time, can maintain the display sheet in a clear state, and does not become visually unpleasant or impair the image. Accordingly, it is an object of the present invention to provide an antifouling overlaminate sheet excellent in convenience and capable of being easily replaced.

The present invention has been made as a result of intensive studies focusing on such problems. Specifically, the present invention is affixed to a printed surface of a display sheet such as a signboard, a poster, a banner, a banner, a road sign, a guide sign, and a construction sign. In a transparent antifouling overlaminate sheet for preventing contamination , silica having an average particle diameter of 0.1 μm or less on the surface of a transparent flexible sheet-like substrate with a water contact angle of 45 ° or less Comprising a hydrophilic resin composition which is a mixed dispersion of an acrylic resin, an acrylic resin, an epoxy resin, a polyester resin, or a urethane resin, and the silica-based resin with respect to 100 parts by weight of the hydrophilic resin composition to form the antifouling agent layer containing fine particles in a range of 5 to 50 parts by weight, Ri Na to form an adhesive layer on the other side, the sheet-like base material, a draw striatum made of a thermoplastic resin Formed cloth and melt An antifouling overlaminate sheet is provided which is a laminated resin film obtained by sandwiching and laminating a film-like body made of a thermoplastic resin in a state .

  The present invention has an excellent anti-contamination effect and is excellent in transparency, and can be applied to a printing surface such as a display sheet to prevent the contamination. It is possible to replace only the adhesive laminate sheet.

  As shown in FIG. 1, the antifouling overlaminate sheet 1 of the present invention comprises an antifouling agent comprising a hydrophilic resin composition having a water contact angle of 45 ° or less on one surface of a flexible sheet-like substrate 2. While forming the layer 3, it is comprised by forming the adhesive layer 4 by a pressure sensitive adhesive in the other surface.

  As the flexible sheet-like substrate 2, a flexible material having excellent transparency is used, and for example, cellophane, celluloid, or a thermoplastic resin can be used. Examples of the thermoplastic resin include high-pressure low-density polyethylene, high-density polyethylene, linear low-density polyethylene, ethylene-based polymers such as ethylene / vinyl acetate copolymer, or propylene / α-propylene mainly composed of polypropylene and propylene. A propylene polymer such as an olefin copolymer, or a thermoplastic resin such as polyester, polyamide, or acrylic resin can be used. Among them, a thermoplastic resin excellent in weather resistance and transparency such as an acrylic polymer or a polyester polymer is desirable.

  The sheet-like substrate 2 of thermoplastic resin can be formed into a film by T-die extrusion molding, cast molding, calendar molding, and inflation molding. In addition, biaxial stretching of the obtained sheet is also a desirable method for improving transparency, waist, tensile strength and the like.

  In the present invention, the sheet is broadly referred to as flat regardless of the thickness, and as the sheet-like substrate 2, a film, a sheet, a plate-like body, a cloth-like body can be used. A thickness of 5 to 300 μm, preferably 15 to 200 μm is used.

  The sheet-like substrate 2 is made of a material having excellent transparency so as not to impair the clearness of the display sheet to be attached, and has a visible light transmittance of 85% or more, preferably 90% or more. Furthermore, a flexible material is used from the viewpoint of adapting to various display sheets. Moreover, the sheet-like base material 2 can also be made into the laminated sheet which laminated | stacked 2 or more types of thermoplastic resins, and as shown in FIG. 2, the surface layer excellent in the coating property on the surface of the base layer 6 excellent in intensity | strength. 7 can be used.

  Further, when used for applications requiring strength such as a transverse membrane and a partition sheet, as shown in FIG. 3, drawn filaments 8a and 8b obtained by uniaxially stretching the above thermoplastic resin are used as warp and weft. As shown in FIG. 4, the cloth-like body 9, or the stretched linear bodies 8 a and 8 b are arranged in parallel so as to intersect vertically and transversely, and a cross-bonded cloth (soft The sheet-like base material 2 in which a thermoplastic resin film 10 is laminated as necessary can be used on the cloth-like body 9 made of a).

  As the drawn filament 8, a thermoplastic resin can be used. As the thermoplastic resin, a thermoplastic resin having excellent mechanical strength is used. Specifically, high-density polyethylene, linear low-density is used. Ethylene polymers such as polyethylene and ethylene / vinyl acetate copolymers, or polypropylene and polypropylene produced using a metallocene catalyst, and propylene polymers such as propylene / α-olefin copolymers based on propylene Polyester, polyamide, etc. can be used. Of these, polyolefins such as ethylene polymers or propylene polymers are desirable.

  As the stretched linear body 8 forming the cloth-like body 9, a tape-like body, monofilament, long fiber, short fiber, or the like can be used. Especially, what woven the tape-shaped body in the flat state from the viewpoint of setting it as the sheet | seat excellent in transparency is preferable.

  Although the obtained cloth-like body 9 can be used as the sheet-like substrate 2 as it is, the cloth-like body 9 is desirably a laminated resin film laminated with a film-like body 10 of a thermoplastic resin.

  As the thermoplastic resin for forming the film-like body 10, an ethylene polymer such as a high-pressure method low-density polyethylene, high-density polyethylene, linear low-density polyethylene, ethylene / vinyl acetate copolymer, or polypropylene or a metallocene catalyst may be used. Propylene-based polymers such as polypropylene, propylene-based α-olefin copolymers mainly composed of propylene, polyesters, polyamides, and the like can be used. Among these, polyolefins such as ethylene polymers or propylene polymers are desirable, and ethylene polymers or propylene polymers produced using a metallocene catalyst are particularly preferable.

  As a method of laminating the film-like body 10 of the thermoplastic resin, it can be carried out by means known per se. For example, the cloth-like body 9 formed of the drawn filaments 8 is supplied to a laminator, and the cloth-like body is obtained. 9 and the molten film-like body 10 can be stacked, and the cloth-like body 9 and the melted thermoplastic resin-like film body 10 can be laminated by pressing with an elastic roll and a metal roll. When the thermoplastic resin film 10 is laminated on both sides, the thermoplastic resin film 10 is laminated on the other surface in the same manner, as shown in FIG. 9 can be a sandwich structure in which thermoplastic resin film-like bodies 10 and 10 are laminated on both sides of the core 9.

  In addition, various additives can be appropriately blended with the thermoplastic resin constituting the sheet-like base material 2 within a range not impairing the effects of the invention. Antioxidants such as phyto- and phosnite-based organic phosphorus and thioethers; light stabilizers such as hindered amines; UV absorbers such as benzophenone, benzotriazole, and benzoate; nonionic, cationic, and anionic Antistatic agents for bisamides, waxes, organometallic salts, etc. Chlorine scavengers such as alkaline earth metal carboxylates, amides, waxes, organometallic salts, esters, etc. Hydrazine-based, amine-acid-based metal inactive agents; antibacterial agents and the like.

  An antifouling agent layer 3 is formed on the front side surface of the flexible sheet-like substrate 2. The antifouling agent layer 3 can be formed of a composition in which silica-based fine particles are added to a hydrophilic film-forming resin. The film-forming resin is a synthetic resin that can form a film on the surface of the sheet-like substrate 2, and a resin in which the antifouling agent layer 3 obtained from the composition to which silica-based fine particles are added has hydrophilicity is used. Is done. The hydrophilicity is such that the water contact angle is 45 ° or less. Specifically, acrylic groups, polyester resins, polyurethane resins, silicone resins (including modified silicones such as silicon polyurea), or reactive groups can be introduced into the molecules of the above thermoplastic resins and cured with a curing agent. Is used. As the form of curing, thermal curing and photocuring are common, but any other type may be used. As the reactive group introduced into the thermosetting resin, a hydroxyl group, a carboxyl group, an epoxy group, an amino group, or the like is common.

  As the silica-based fine particles, a fine powder of a silica-based material or a fine powder surface-treated with a silica-based material is used, and an inorganic powder surface-treated with silica, silica sol, or an organosilicate compound is used.

  A suitable silica-based fine particle is an inorganic oxide sol surface-treated with a silica sol or an organosilicate compound, and the average particle size of the silica-based fine particle is usually 0.1 μm or less. The amount of these silica-based fine particles is usually in the range of 0.1 to 70 parts by weight, preferably 3 to 60 parts by weight, particularly preferably 5 to 50 parts by weight with respect to 100 parts by weight of the film-forming resin. . If the amount of the silica-based fine particles is too small, the hydrophilicity is insufficient, and the antifouling protection effect such as stain resistance is lowered. On the other hand, if the amount is too large, the film performance and the adhesion to the sheet-like substrate 2 are deteriorated. Getting worse.

  The obtained antifouling agent composition (coating solution) is applied onto the surface of the sheet-like substrate 2 and dried or cured to form a coating film. The curing conditions are not particularly limited, but are usually performed at a temperature of 60 to 150 ° C. for 1 to 20 minutes. The thickness of the antifouling agent layer 3 is usually 0.1 to 15 μm, preferably 0.5 to 10 μm.

  The antifouling overlaminate sheet 1 is usually prepared so that the water contact angle on the surface is 45 degrees or less, preferably 40 degrees or less, in the initial stage of use (within one month immediately after construction). If the water contact angle on the surface of the antifouling overlaminate sheet 1 is 45 degrees or less, the stain resistance can be effectively enhanced and maintained for a long period of time.

  A pressure-sensitive adhesive is applied to the other surface of the sheet-like substrate 2 to form the pressure-sensitive adhesive layer 4. The surface of the sheet-like substrate 2 on which the pressure-sensitive adhesive layer 4 is applied has a physical treatment such as sandblasting, physical treatment such as flame treatment, corona treatment or plasma treatment on the surface in order to increase the adhesion with the pressure-sensitive adhesive. It is preferable to perform chemical treatment or primer treatment. The pressure-sensitive adhesive is usually dissolved in an appropriate organic solvent or made into an emulsion, coated on the sheet-like substrate 2 and then dried, or coated on a process paper that has been subjected to a release treatment. The post-dried material is transferred onto a support to obtain an antifouling overlaminated sheet 1 in which the sheet-like substrate 2 and the pressure-sensitive adhesive layer 4 are laminated. There is no restriction | limiting in a coating means and a drying method, A well-known thing is employable.

  The pressure-sensitive adhesive used in the present invention may be those generally used as pressure-sensitive adhesives for pressure-sensitive adhesive tapes, such as acrylic resin-based pressure-sensitive adhesives, rubber-based pressure-sensitive adhesives such as natural rubber and synthetic rubber, and styrene-butadiene- Styrene block copolymer, styrene-isoprene-styrene block copolymer, block copolymer adhesive such as hydrogenated products, ethylene-vinyl acetate copolymer adhesive, polyvinyl ether resin adhesive, silicone resin Among them, an acrylic resin-based pressure-sensitive adhesive that is excellent in durability and weather resistance and has little dirt during handling is preferably used. These pressure-sensitive adhesives may be used alone or in combination of two or more.

  The form of these pressure-sensitive adhesives is not particularly limited, and for example, any form such as a solution-type pressure-sensitive adhesive, an emulsion-type pressure-sensitive adhesive, a reactive pressure-sensitive adhesive, a photopolymerizable monomer-type pressure-sensitive adhesive, etc. Good.

  In addition, these pressure-sensitive adhesives may include cross-linking agents such as polyisocyanate compounds, aziridine compounds, metal chelate compounds, tackifiers, couplings, etc., as long as the object of the present invention is not impaired. Agent, filler, softener, plasticizer, surfactant, antioxidant (anti-aging agent), heat stabilizer, light stabilizer, ultraviolet absorber, colorant, antifoaming agent, flame retardant, antistatic agent, etc. One or two or more of these various additives may be added.

  Moreover, although the adhesive layer 4 formed on the sheet-like base material 2 is not specifically limited, It is preferable that the thickness is 10 micrometers-0.5 mm. When the thickness of the pressure-sensitive adhesive layer is less than 10 μm, the adhesion to the rough surface of the antifouling overlaminated sheet 1 and the unevenness followability may be insufficient, and conversely the thickness of the pressure-sensitive adhesive layer 4 is 0.00. If it exceeds 5 mm, the tackiness and adhesive force will no longer improve, but the cost will be high.

  The acrylic resin-based adhesive will be described in more detail. As the acrylic resin-based adhesive, an acrylic polymer obtained by polymerizing a carboxyl group-containing monomer and a (meth) acrylic acid alkyl ester monomer is used.

  The number of carbon atoms of the alkyl group of the (meth) acrylic acid alkyl ester monomer is preferably about 4 to 12, and specifically, n-butyl (meth) acrylate, isobutyl (meth) acrylate, n-octyl (meth) acrylate. , Isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isononyl (meth) acrylate, and the like, and n-butyl acrylate and 2-ethylhexyl acrylate are particularly preferable.

  Examples of the carboxyl group-containing monomer include monocarboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, and itaconic acid; dicarboxylic acids such as fumaric acid and maleic acid, and monoesters thereof. Of these carboxyl group-containing radical polymerizable monomers, acrylic acid and methacrylic acid are preferably used. The carboxyl group-containing polymerizable monomer is preferably about 1 to 20% by weight of the whole monomer.

  In the acrylic resin-based pressure-sensitive adhesive used in the present invention, a small amount of a modifying component monomer may be copolymerized for the purpose of adjusting the glass transition temperature, polarity and the like. Examples of such monomers include methyl (meth) acrylate, ethyl (meth) acrylate, acrylamide, vinyl acetate, styrene, acrylonitrile, vinyl pyrrolidone and the like.

  The acrylic polymer is blended with a polyfunctional compound having two or more functional groups that react with a carboxyl group in the molecule, or a polyfunctional compound and a monofunctional compound having one functional group in the molecule. Can be crosslinked. Examples of this type of functional group-containing compound include an isocyanate group-containing compound, an epoxy group (or glycidyl group) -containing compound, an aziridinyl group-containing compound, a metal complex, and a melamine compound.

  Moreover, it is preferable to mix | blend a small amount of plasticizers in an adhesive composition. The kind of the plasticizer to be blended is not limited. For example, a low molecular plasticizer such as an ester of an aliphatic polyvalent carboxylic acid, an ester of an aromatic polyvalent carboxylic acid, a phosphate ester or a high molecular weight such as a polyester. Molecular plasticizers can be exemplified, but aliphatic dibasic acid esters are particularly effective, and adipic acid diester is most preferred. The blending amount is preferably 0.05 to 4% by weight.

  On the pressure-sensitive adhesive layer 4, a release paper that has been subjected to a release treatment is generally affixed in order to lighten the peeling force (also referred to as a deployment force) when rewinding. Examples of the release treatment include application of a silicon release agent accompanied by a curing reaction, a fluorine release agent, and a long-chain alkyl graft polymer release agent, if necessary.

(Measurement method)
a. Contact angle:
One drop of distilled water was dropped on the surface of the antifouling agent layer, and the contact angle after 1 minute was measured.
b. Light transmittance:
It measured based on JIS-K7105.
c. Antifouling performance:
The difference in whiteness L ^* value was measured in accordance with a type I test for promoting antifouling materials for civil engineering (using a 5% by weight tap water dispersion of carbon black).
d. Adhesive strength:
It measured based on JIS-Z0237.

Example 1
A 50 μm thick acrylic transparent film “Sanduren 014NST” (trade name, manufactured by Kaneka Chemical Industry Co., Ltd.) was used as an antifouling agent (A) with a polyester resin and colloidal silica fine particles (5 wt%). The mixed dispersion was applied to a thickness of 0.5 μm with a gravure coater and dried and cured at 100 ° C. for 1 minute to form an antifouling agent layer.

Thereafter, the acrylic pressure-sensitive adhesive composition “Nissetsu KP-802L / CK-401 = 100 parts by weight / 1 part by weight of a mixture” [trade name, manufactured by Nippon Carbide Industries, Ltd.] solution is dried on the release agent. The pressure-sensitive adhesive layer was applied to a thickness of about 25 g / m ^2, and the pressure-sensitive adhesive dried with a hot air circulation dryer at 100 ° C. for 1 minute was bonded together, and the conditions were 23 ° C. and 65% RH for 7 days. Crosslinking was performed to obtain an antifouling overlaminate sheet. The hydrophilicity, light transmittance, antifouling properties and adhesive strength of the obtained antifouling overlaminate sheet were measured. The results are shown in Table 1.

(Examples 2 to 10, Comparative Examples 1 to 5)
As shown in Table 1, instead of the antifouling agent (A) in Example 1, an acrylic resin and an antifouling agent (B) containing 8% by weight of colloidal silica fine particles were applied and cured by UV irradiation. , Colloidal silica-based fine particles of antifouling agent (B) are mixed in amounts of 12, 20% by weight (antifouling agents (C), (D)), or urethane resin and colloidal silica-based fine particles Antifouling agent (F) or a silicon-based resin and colloidal silica fine particle coated antifouling agent (G) was prepared, and the antifouling overlaminate sheet was prepared in the same manner as in Example 1. Obtained.

  Further, an antifouling agent (H) of acrylic resin and colloidal silica fine particles (I), a transparent film made of vinylidene fluoride having a thickness of 50 μm “DENKA DX film 14S0250” [trade name, manufactured by Denki Kagaku Kogyo Co., Ltd. Or an antifouling agent (C) of acrylic resin and colloidal silica fine particles, a transparent film made of 50 μm polyester “Diafoil T600” [trade name, manufactured by Mitsubishi Chemical Polyester Film Co., Ltd.], and A 50 μm vinyl chloride transparent film “HI-S Paint 5080E” [trade name, manufactured by Nippon Carbide Industries, Ltd.] was used to obtain an antifouling overlaminate sheet in the same manner as in Example 1. It was.

  Further, for comparison, the antifouling agent (E) containing 0.05% by weight of the colloidal silica fine particles of the antifouling agent (A) comprising the polyester resin of Example 1 and the colloidal silica fine particles is used. Evaluation was conducted in the same manner as in Example 1 using a sheet to which no antifouling agent was applied. The results are shown in Table 1. Moreover, it preserve | saved for a long time and measured the time-dependent change of antifouling performance. The results are shown in Table 2.

The longitudinal cross-sectional view which shows an example of this invention antifouling overlamination sheet Longitudinal sectional view showing another example of sheet-like substrate Longitudinal sectional view showing another example of the antifouling overlaminate sheet of the present invention Longitudinal sectional view showing still another example of the antifouling overlaminated sheet of the present invention

Explanation of symbols

1. 1. Antifouling overlamination sheet 2. Sheet-like substrate Antifouling agent layer 4. 5. Adhesive layer Base layer 7. Surface layer 8. 8. Elongated striated body Cloth-like body 10. Film

Claims (1)

In transparent antifouling overlamination sheets that are attached to the printing surface of display sheets such as signs, posters, banners, banners, road signs, guide signs, construction signs, etc.
On the surface of a transparent flexible sheet-like substrate, the contact angle of water is 45 ° or less and the average particle size is 0.00.
It consists of a hydrophilic resin composition which is a mixed dispersion of silica-based fine particles of 1 μm or less and acrylic resin, epoxy resin, polyester resin or urethane resin, and with respect to 100 parts by weight of the hydrophilic resin composition to form the antifouling agent layer comprising in the range of 5 to 50 parts by weight of the silica fine particles Te, Ri Na to form an adhesive layer on the other side,
The sheet-like base material is a cloth-like body formed of a stretched linear body made of a thermoplastic resin, and a molten state.
A laminated resin film obtained by sandwiching and laminating a film-like body made of a thermoplastic resin in a state
Antifouling overlaminate sheet characterized by that.

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