JP2010084248A - Wallpaper for clean room - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide wallpaper for clean rooms which prevents or controls the release of VOC. <P>SOLUTION: There is provided the wallpaper for the clean rooms, which does not contain a vinyl chloride-based resin, wherein an adhesive layer, a non-foamed polyolefin-based resin layer, and a protecting layer 1 are sequentially laminated to a paper-based substrate. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a wallpaper for a clean room.

  A clean room of a manufacturing facility such as a semiconductor, a liquid crystal, a magnetic disk, a medical device, and an optical machine needs to have a certain degree of air cleanliness. Therefore, it is required that the wallpaper of the clean room does not dissipate organic volatile substances (VOC) or the like, for example.

  Conventionally, as a general wallpaper, a vinyl chloride wallpaper in which a polyvinyl chloride (PVC) resin layer and a pattern printing layer are provided on a paper-based substrate, and a vinyl chloride paste containing a foaming agent on a vinyl chloride sheet are used. A foamed wallpaper having a concavo-convex pattern on the surface obtained by foaming the paste layer after coating is known.

  However, since these PVC-based wallpaper use a large amount of VOC in production, the wallpaper contains a large amount of VOC. Therefore, there is a problem that the VOC is volatilized from the wallpaper and released into the clean room.

  On the other hand, a technique for suppressing the release of VOC by laminating a film (eval film) made of an ethylene-vinyl alcohol copolymer resin on the surface has been proposed (Patent Document 1).

However, even if an EVAL film is laminated on the surface of the wallpaper, VOC may be released from the paper-based substrate side. In particular, the wallpaper is stored in a state of being rolled up after production (in a state where the paper-based substrate constituting the wallpaper and the eval film are in contact). Therefore, the VOC released from the paper-based substrate side of the wallpaper may adhere to the surface eval film, and the attached VOC may be released into the air after construction. In such a case, it is difficult to say that it is suitable for a clean room.
JP 2006-282834

  The main object of the present invention is to provide a clean room wallpaper in which the release of VOC is prevented or suppressed.

  As a result of intensive studies, the present inventor has found that a wallpaper adopting a specific configuration can achieve the above object, and has completed the present invention.

That is, the present invention relates to the following wallpaper.
1. A wallpaper for a clean room which does not contain a vinyl chloride resin, and is formed by sequentially laminating an adhesive layer, a polyolefin non-foamed resin layer, and a protective layer 1 on a paper substrate.
2. Item 2. The clean room wallpaper according to Item 1, wherein the protective layer 1 contains an antistatic agent.
3. Item 2. The clean room wallpaper according to Item 1, wherein a protective layer 2 is further laminated on the protective layer 1.
4). Item 4. The clean room wallpaper according to Item 3, wherein a pattern layer is provided between the protective layer 1 and the protective layer 2.
5). Item 5. The clean room wallpaper according to Item 3 or 4, wherein the protective layer 2 contains an antistatic agent.

  The wallpaper for the clean room of the present invention is a wallpaper that does not contain a vinyl chloride resin, and is formed by laminating an adhesive layer, a polyolefin non-foamed resin layer, and a protective layer 1 in this order on a paper substrate.

  The vinyl chloride resin is a polymer obtained by homopolymerizing vinyl chloride, a copolymer of vinyl chloride and other monomers that can be copolymerized with vinyl chloride, and a mixture of the polymer and the copolymer. Say.

  According to the present invention, a wallpaper in which the release of VOC is prevented or suppressed is obtained by laminating a polyolefin-based non-foamed resin layer through an adhesive layer between the paper-based substrate and the protective layer 1.

  In this invention, when forming the said polyolefin-type non-foamed resin layer, the usage-amount of the material used as the cause of generation | occurrence | production of VOC can be suppressed effectively. Therefore, the wallpaper of the present invention has a small amount of VOC emission.

  On the other hand, a plasticizer is usually used because it is necessary to impart plasticity to a vinyl chloride resin when producing a vinyl chloride wallpaper. As the plasticizer, phthalic acid esters (for example, di-n-octyl phthalate, diisononyl phthalate, etc.), adipic acid esters, sebacic acid esters, and the like are used. Since these plasticizers cause VOC generation, PVC wallpaper releases a large amount of VOC.

  The wallpaper of the present invention in which the release of VOC is prevented or suppressed can be used not only on the wall surface of a house or the like, but particularly on the wall surface of a clean room or a hospital for manufacturing precision equipment or the like. In particular, the wallpaper of the present invention can be suitably used as a wallpaper for a clean room.

The paper-based substrate is not particularly limited as long as it has mechanical strength, heat resistance and the like suitable as a wallpaper substrate, and a fibrous sheet can be generally used.

Specifically, among fiber sheets, flame retardant paper (pulp-based sheets treated with flame retardants such as guanidine sulfamate and guanidine phosphate); inorganic additives such as aluminum hydroxide and magnesium hydroxide Inorganic paper including; fine paper; thin paper and the like.
The basis weight of the paper quality substrate is not limited, but preferably about 50 to 300 g / m ^2, about 50 to 80 g / m ² is more preferable.

Adhesive Layer In order to improve the adhesion between the following non-foamed resin layer and the paper base, an adhesive layer may be formed between the paper base and the following non-foamed resin layer.

  Examples of the resin component constituting the adhesive layer include ethylene-vinyl acetate copolymer (EVA), ethylene-methyl methacrylate copolymer (EMMA), ethylene-ethyl acrylate copolymer (EEA), and ethylene-methyl acrylate. Examples thereof include at least one such as a copolymer (EMA). Among these, EVA is particularly preferable.

  From the viewpoint of ease of bonding with a paper-based substrate, the melt flow rate value (hereinafter abbreviated as “MFR”) of the adhesive layer is preferably larger than the MFR of the following non-foamed resin layer. The MFR can be measured by a test method described in JIS K 7210 (thermoplastic flow test method). As test conditions, “190 ° C., 21.18 N (2.16 kgf)” described in JIS K 6760 is adopted.

  Although the thickness of an adhesive bond layer is not limited, about 5-20 micrometers is preferable and about 10-15 micrometers is more preferable.

Polyolefin-based non-foamed resin layer The polyolefin-based non-foamed resin layer is a resin layer formed using a polyolefin-based resin as a resin component. Unlike the foamed wallpaper, the wallpaper of the present invention does not have a foamed resin layer. The wallpaper of the present invention has a polyolefin non-foamed resin layer formed in place of the foamed resin layer.

  Examples of the polyolefin resin include polyethylene, polypropylene, polybutene, polymethylpentene, ethylene-propylene copolymer, EVA, ethylene-acrylic acid copolymer (EAA), EMMA, ethylene-propylene-butene copolymer, Examples thereof include at least one such as a polyolefin-based thermoplastic elastomer. Among these, EMAA or EVA is particularly preferable, and EMAA is more preferable.

  The content of the polyolefin resin in the non-foamed resin layer is preferably about 35 to 80% by weight, more preferably about 40 to 60% by weight.

  In addition, the said non-foamed resin layer may further contain a well-known additive as needed. Examples of known additives include inorganic fillers, pigments, flame retardants, heat stabilizers, lubricants, fungicides, and antibacterial agents.

  Examples of the inorganic filler include calcium carbonate, aluminum hydroxide, magnesium hydroxide, antimony trioxide, zinc borate, and a molybdenum compound. These can be used alone or in combination of two or more. By using an inorganic filler, an effect of suppressing gaps, an effect of improving surface characteristics, and the like are obtained. The content of the inorganic filler is preferably about 0 to 100 parts by weight and more preferably about 20 to 70 parts by weight with respect to 100 parts by weight of the polyolefin resin.

  About a pigment, at least 1 sort (s) of a well-known inorganic pigment and an organic pigment can be used. By using a pigment, the non-foamed resin layer can be colored. Inorganic pigments include, for example, titanium oxide, zinc white, carbon black, black iron oxide, yellow iron oxide, yellow lead, molybdate orange, cadmium yellow, nickel titanium yellow, chrome titanium yellow, iron oxide (valve), and cadmium. Examples thereof include red, ultramarine blue, bitumen, cobalt blue, chromium oxide, cobalt green, aluminum powder, bronze powder, titanium mica, and zinc sulfide. Examples of the organic pigment include aniline black, perylene black, azo type (azo lake, insoluble azo, condensed azo), polycyclic (isoindolinone, isoindoline, quinophthalone, perinone, flavantron, anthrapyrimidine, anthraquinone, quinacridone, Perylene, diketopyrrolopyrrole, dibromoanthanthrone, dioxazine, thioindigo, phthalocyanine, indanthrone, halogenated phthalocyanine) and the like. These can be used alone or in combination of two or more. The content of the pigment in the non-foamed resin layer is not particularly limited, and may be set as appropriate from the viewpoint of design and the like.

  The thickness of the non-foamed resin layer is not limited, but is preferably about 5 to 200 μm, and more preferably about 20 to 100 μm.

Protective layer 1
A protective layer 1 is formed on the non-foamed resin layer. By forming the protective layer 1, the scratch resistance of the wallpaper can be improved.

  The resin constituting the protective layer 1 is not particularly limited, but an ethylene-methacrylic acid copolymer (EMAA) is preferable. Although content of EMAA is not specifically limited, For example, when the wallpaper of this invention has the protective layer 2 mentioned later, about 70-100 weight% of content of EMAA in the protective layer 1 is preferable.

  When the protective layer 1 is on the outermost surface of the wallpaper, the protective layer 1 preferably contains an antistatic agent. By containing the antistatic agent, the charging of the wallpaper is prevented or suppressed. As a result, minute floating matters (for example, dust, dust, etc.) in the air are difficult to be adsorbed on the wallpaper.

  Examples of the antistatic agent include an anionic surfactant, a cationic surfactant, a nonionic surfactant, a nonionic surfactant, and an ionic polymer. These can be used individually by 1 type or in combination of 2 or more types. Of these, ionic polymer compounds are particularly preferred, and lithium ionic polymer compounds are more preferred. Examples of the lithium ionic polymer compound include a compound in which lithium perchlorate is compounded with a polymer mainly composed of polyalkylene glycol, a compound in which lithium is compounded with polystyrene sulfonic acid, and polystyrene sulfonic acid-maleic. The compound etc. which compounded lithium in the acid copolymer are mentioned.

  In addition to the above-described antistatic agents, known antistatic agents such as metal antistatic agents, carbon antistatic agents, and organic complex antistatic agents can also be used.

  Although content of the said antistatic agent in the protective layer 1 is not specifically limited, About 5-100 weight part is preferable with respect to 100 weight part of resin components, and about 10-50 weight part is more preferable.

  Although the thickness of the protective layer 1 is not limited, about 1-50 micrometers is preferable and about 3-20 micrometers is more preferable.

A pattern layer may be formed on the pattern layer protective layer 1 as necessary. By providing the pattern layer, the design can be suitably imparted to the wallpaper.

  Examples of the design pattern include a wood grain pattern, a stone pattern, a grain pattern, a tiled pattern, a brickwork pattern, a cloth pattern, a leather pattern, a geometric figure, a character, a symbol, and an abstract pattern. The pattern can be selected according to the type of wallpaper.

  The pattern pattern layer can be formed, for example, by printing a pattern pattern on the protective layer 1. Examples of printing methods include gravure printing, flexographic printing, silk screen printing, and offset printing. As the printing ink, a known printing ink containing a colorant, a vehicle, and a solvent can be used.

  As the colorant, for example, known inorganic pigments and organic pigments can be used. Inorganic pigments include, for example, titanium oxide, zinc white, carbon black, black iron oxide, yellow iron oxide, yellow lead, molybdate orange, cadmium yellow, nickel titanium yellow, chrome titanium yellow, iron oxide (valve), and cadmium. Examples thereof include red, ultramarine blue, bitumen, cobalt blue, chromium oxide, cobalt green, aluminum powder, bronze powder, titanium mica, and zinc sulfide. Examples of the organic pigment include aniline black, perylene black, azo type (azo lake, insoluble azo, condensed azo), polycyclic (isoindolinone, isoindoline, quinophthalone, perinone, flavantron, anthrapyrimidine, anthraquinone, quinacridone, Perylene, diketopyrrolopyrrole, dibromoanthanthrone, dioxazine, thioindigo, phthalocyanine, indanthrone, halogenated phthalocyanine) and the like.

  The vehicle can be set according to the type of the base sheet. For example, acrylic resin, styrene resin, polyester resin, urethane resin, polyvinyl butyral resin, alkyd resin, petroleum resin, ketone resin, epoxy resin Examples thereof include resins, melamine resins, fluorine resins, silicone resins, fiber derivatives, rubber resins, and the like.

  Examples of the solvent (or dispersion medium) contained in the printing ink include petroleum-based organic solvents such as hexane, heptane, octane, toluene, xylene, ethylbenzene, cyclohexane, and methylcyclohexane; ethyl acetate, butyl acetate, and 2-methoxyacetate Ester-based organic solvents such as ethyl and 2-ethoxyethyl acetate; alcohol-based organic solvents such as methyl alcohol, ethyl alcohol, normal propyl alcohol, isopropyl alcohol, isobutyl alcohol, ethylene glycol, propylene glycol; acetone, methyl ethyl ketone, methyl isobutyl ketone Ketone organic solvents such as cyclohexanone; ether organic solvents such as diethyl ether, dioxane and tetrahydrofuran; dichloromethane, carbon tetrachloride, trichloroethylene Chlorinated organic solvents tetrachlorethylene and the like; and water.

  The thickness of the pattern layer is different from the type of pattern, but is preferably about 0.1 to 10 μm.

  In addition, you may form the colored layer (solid layer) which does not have a design pattern between the said design pattern layer and the said protective layer 1. FIG. Moreover, you may form the said colored layer instead of the said pattern pattern layer. The colored layer can be formed by solid coating with the printing ink.

Protective layer 2
When forming the pattern layer, it is preferable to further form a protective layer 2 on the pattern layer.

  The protective layer 2 is preferably a layer formed using an aqueous emulsion composition or an ionizing radiation curable resin.

  As the aqueous emulsion composition, specifically, an emulsion in which a resin component is dispersed in an aqueous solvent (aqueous emulsion resin) containing a colorant can be used.

  As the resin component, for example, resins used in known water-based coating agents, water-based paints, and the like can be used. Examples of such resins include acrylic resins, urethane resins, epoxy resins, acrylic urethane resins, vinyl acetate resins, and the like. These can be used alone or in combination of two or more. Among these, it is preferable to use an acrylic urethane resin in terms of heat resistance, water resistance, weather resistance, and the like. When using an acrylic urethane-based resin, the number average molecular weight is preferably about 10,000 to 1,000,000.

  As the aqueous solvent, water or a mixed solvent of water and an organic solvent can be used. As the water, for example, industrial water of a grade used in known aqueous coating agents can be used.

  As the organic solvent, for example, lower alcohols such as ethanol, isopropyl alcohol and n-propyl alcohol, and water-soluble organic solvents such as glycols and glycol esters can be suitably used. The water-soluble organic solvent is used for the purpose of improving the flowability of the aqueous emulsion resin, improving the wettability with respect to the pattern layer, adjusting the drying property, etc. The amount is determined. In the case of the mixed solvent, the ratio of water and the organic solvent is not particularly limited, and may be appropriately adjusted so that the ratio of the organic solvent in the mixed solvent is 80% or less.

  If necessary, extender pigments can be added to the aqueous emulsion composition for the purpose of at least one of blocking resistance, improvement of heat resistance during embossing, improvement of adhesive force due to anchor effect, and the like.

  As the extender pigment, known or commercially available pigments can be used, and there is no particular limitation. For example, inorganic pigments such as white clay, talc, clay, diatomaceous earth, calcium carbonate, barium sulfate, titanium oxide, alumina white, silica, kaolin, mica, aluminum hydroxide, polyacrylate, polyurethane, polyester, polyethylene, polypropylene Organic pigments such as polyvinyl chloride, polyvinylidene chloride, polystyrene, polysiloxane, phenol resin, epoxy resin, benzoguanamine resin, or organic pigments composed of these copolymers can be used. These are usually desirably used in the form of particles.

  What is necessary is just to determine suitably the usage-amount of the aqueous solvent in an aqueous | water-based emulsion composition from the range from which solid content in an aqueous | water-based emulsion composition will be 20 to 80 weight%.

  In addition, an ionizing radiation curable resin may be used as the resin constituting the protective layer 2. The protective layer 2 formed by curing a resin layer formed using an ionizing radiation curable resin by electron beam irradiation can further improve the surface strength, stain resistance, and the like of wallpaper. In the case of using an ionizing radiation curable resin, an ionizing radiation curable resin layer may be formed after a primer layer is formed on the pattern layer in order to improve adhesion to the pattern layer.

  The ionizing radiation curable resin is not particularly limited, and prepolymers (including oligomers) and / or monomers containing radically polymerizable double bonds capable of undergoing a crosslinking reaction upon irradiation with ionizing radiation such as ultraviolet rays and electron beams. The transparent resin which has as a main component can be used. These prepolymers or monomers can be used alone or in combination. The curing reaction is usually a cross-linking curing reaction.

  Specifically, as the prepolymer or monomer, a compound having in the molecule a radically polymerizable unsaturated group such as a (meth) acryloyl group or (meth) acryloyloxy group, or a cationically polymerizable functional group such as an epoxy group. Is mentioned. Further, a polyene / thiol prepolymer based on a combination of polyene and polythiol is also preferable. Here, the (meth) acryloyl group means an acryloyl group or a methacryloyl group.

  When the protective layer 2 is on the outermost surface of the wallpaper, the protective layer 2 preferably contains an antistatic agent. By containing the antistatic agent, the charging of the wallpaper is prevented or suppressed. As a result, minute floating matters (for example, dust, dust, etc.) in the air are difficult to be adsorbed on the wallpaper.

  As an antistatic agent, the antistatic agent illustrated by the item of the said protective layer 1 can be used 1 type, or 2 or more types, for example. Of these, ionic polymer compounds are particularly preferred, and lithium ionic polymer compounds are more preferred. Examples of the lithium ionic polymer compound include a compound in which lithium perchlorate is compounded with a polymer mainly composed of polyalkylene glycol, a compound in which lithium is compounded with polystyrene sulfonic acid, and polystyrene sulfonic acid-maleic. The compound etc. which compounded lithium in the acid copolymer are mentioned.

  Although content of the said antistatic agent in the protective layer 2 is not specifically limited, About 35-140 weight part is preferable with respect to 100 weight part of resin components, and about 70-100 weight part is more preferable.

  The thickness of the protective layer 2 is different depending on the kind of the pattern and the like, but is preferably about 0.1 to 15 μm.

Primer layer A primer layer may be formed on the protective layer 1 prior to forming the pattern layer. By forming the primer layer, the pattern layer and the protective layer 2 can be easily formed.

  The primer layer can be formed by applying a known primer agent on the protective layer 1.

  For example, a primer agent composed of a base resin, an additive, and a solvent can be used as the primer agent.

  Examples of the base resin include acrylic resin, urethane resin, EVA and the like. These base resins can be used alone or in combination of two or more.

  In particular, the acrylic resin is preferably used in combination with the urethane resin. Since the acrylic resin has low adhesiveness, when the acrylic resin is used alone as the base resin, there is a problem that the primer agent is not sufficiently coated on the object to be coated and adheres to the roll (roll removal problem). There is a fear. In addition, when a urethane resin is used alone as the base resin, the urethane resin has high adhesiveness, which may cause a problem of roll removal or blocking. These problems can be suitably solved by using an acrylic resin and a urethane resin in combination. What is necessary is just to set suitably the mixture ratio of an acrylic resin and a urethane resin according to the adhesiveness etc. of a primer agent.

  Examples of the additive include extender pigments such as silica and acrylic beads; silicon; thickeners (viscosity modifiers) and the like.

  By containing the extender pigment in the primer agent, the base (the non-foamed resin layer, the protective layer 1, etc.) can be suitably concealed. In particular, when acrylic beads are included as extender pigments, the slipperiness of the primer layer can be improved, and the roll removal and blocking can be suitably avoided.

  By including silicon in the primer agent, the tackiness of the primer agent can be relaxed. Further, the slipperiness of the primer layer can be improved, and the roll removal and blocking can be suitably avoided.

  By containing the thickener in the primer agent, the dispersibility of the base resin and additives can be improved.

  As the solvent, water or an organic solvent (for example, isopropyl alcohol) can be used.

The coating amount of the primer agent is preferably 0.1 to 50 about g / m ^2, more preferably 1 to 10 about g / m ^2.

  Examples of the coating method include spin coating, gravure coating, and comma coating.

  After applying the primer agent, the obtained coating film may be dried as necessary. What is necessary is just to set suitably about drying conditions according to the state of the said coating film, etc.

  The thickness of the primer layer is preferably about 0.1 to 20 μm, more preferably about 0.5 to 5 μm.

The wallpaper of the present invention is obtained, for example, by forming the adhesive layer, the non-foamed resin layer, and the protective layer 1 in this order on the paper substrate, and then on the protective layer 1 of the obtained laminate. And a primer layer, a pattern layer and a protective layer 2 are formed in this order.

  A method for manufacturing the laminate is not particularly limited. For example, when the adhesive layer, the non-foamed resin layer, and the protective layer 1 are sequentially laminated on a paper-based substrate, a composition for forming the non-foamed resin layer and the protective layer 1 are formed. The composition for forming the adhesive layer and the composition for forming the adhesive layer may be placed in separate cylinders, and three types and three layers may be simultaneously extruded and formed and laminated. When the protective layer 1 contains the antistatic agent, the antistatic agent may be contained in the composition for forming the protective layer 1.

  The three-layer laminate formed by the extrusion molding may be directly extruded onto a paper-based substrate, or may be formed separately from the paper-based substrate. In the former case, since the resin layer has good adhesiveness due to heat of fusion, it is in close contact with the paper substrate. In the case of the latter, it can adhere | attach by mounting a laminated body on a paper-like base material, and carrying out heat lamination.

  When the protective layer 2 is formed and the antistatic agent is contained in the protective layer 2, the antistatic agent may be contained in the composition for forming the protective layer 2.

  When the protective layer 1 is on the outermost surface of the wallpaper, the protective layer 1 may be irradiated with an electron beam. In addition, when the protective layer 2 is on the outermost surface of the wallpaper, the primer layer, the pattern layer and the protective layer 2 are sequentially formed on the protective layer 1 of the obtained laminate, and then the protective layer 2 is irradiated with an electron beam. You may go. By irradiating the protective layer 1 or the protective layer 2 with an electron beam, the scratch resistance of the wallpaper can be improved.

  The energy of the electron beam is preferably about 150 to 250 kV. The irradiation dose is preferably about 10 to 100 kGy. A known electron beam irradiation apparatus can be used as the electron beam source.

  When performing electron beam irradiation, the composition may contain a crosslinking aid.

  Any crosslinking aid may be used as long as it promotes crosslinking by electron beam irradiation. Examples thereof include polyfunctional monomers such as neopentyl glycol dimethacrylate and trimethylolpropane trimethacrylate, oligomers, and the like. These can be used alone or in combination of two or more. About 0-10 weight part is preferable with respect to 100 weight part of resin components, and, as for content of a crosslinking adjuvant, 1-4 weight part is more preferable.

  According to the present invention, a wallpaper in which the release of VOC is prevented or suppressed is obtained by laminating a polyolefin-based non-foamed resin layer through an adhesive layer between the paper-based substrate and the protective layer 1.

  In addition, when the outermost layer (protective layer 1 or protective layer 2) of the wallpaper of the present invention contains an antistatic agent, charging can be prevented or suppressed. Therefore, it is difficult to adsorb minute suspended matters (for example, dust and dust) in the air.

  Therefore, the wallpaper of the present invention can be used not only on the wall surface of a house or the like, but also particularly on the wall surface of a clean room or hospital for manufacturing precision instruments and the like, and can be suitably used particularly as a wallpaper for a clean room.

  In addition, since the wallpaper of the present invention does not contain a vinyl chloride resin, it has little impact on the environment.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. However, the present invention is not limited to the examples.

Example 1
In order to form the protective layer 1, 100 parts by weight of EMAA (product name “Nucrel N1560”, MFR: 60 g / 10 min, MA content: 15 wt%, manufactured by Mitsui DuPont Polychemical) was prepared.

  In order to form an adhesive layer, 100 parts by weight of EVA (product name “Evaflex EV150”, MFR: 30 g / 10 min, VA content: 33 wt%, manufactured by Mitsui DuPont Polychemical) was prepared.

  In order to form a polyolefin-based non-foamed resin layer, a composition containing the components shown in Table 1 below was prepared.

  The above resin and the resin-containing composition were melted, and a three-layer coextrusion lamination was performed using a T-die extruder to obtain a laminate composed of protective layer 1 / olefin-based non-foamed resin layer / adhesive layer. The thicknesses of the protective layer 1, the olefinic non-foamed resin layer, and the adhesive layer were 10 μm, 100 μm, and 10 μm, respectively. In this T-die extruder, Table 1 for forming a cylinder containing EMAA for forming the protective layer 1, a cylinder containing EVA for forming the adhesive layer, and an olefin-based non-foamed resin layer. The temperatures of the cylinders containing the components were 140 ° C., 100 ° C. and 120 ° C., respectively. The die temperatures were all 120 ° C.

The obtained laminate was pressed and laminated on a paper substrate having a thickness of 110 μm (basis weight 70 g) so that the paper substrate and the adhesive layer were in contact with each other. In addition, before pressurization and lamination, the paper base material surface was heated at 120 ° C. for 10 seconds in advance.
Furthermore, a texture pattern (pattern pattern layer) was printed on the protective layer 1 using urethane-acrylic water-based ink (product name “Hydric” manufactured by Dainichi Seika Kogyo Co., Ltd.). The thickness of the pattern layer was 1 μm.

  And it contains an antistatic agent (lithium ionic polymer compound; trade name “SD-NT Antistatic Agent L-1” manufactured by Dainichi Seika Kogyo Co., Ltd.) in an aqueous emulsion composition in which urethane-acrylic resin is dispersed in water. The printed resin composition (resin composition containing 10 parts by weight of an antistatic agent with respect to 100 parts by weight of urethane acrylate-based electron beam curable resin) is printed on the pattern layer by gravure printing to 2 μm. A thick protective layer 2 was formed.

  Through the above process, wallpaper was created.

Example 2
Instead of urethane-acrylic water-based ink, wallpaper was made in the same manner as in Example 1 except that the pattern layer was formed using organic ink (trade name “UE (NT) Solid”, Showa Ink Industries). Produced.

Comparative Examples 1-3
Commercially available polyvinyl chloride wallpaper (3 types) shown in Table 2 below was prepared.

Test Example 1 (Measurement of VOC emission rate)
The VOC emission density | concentration of the wallpaper of Examples 1-2 and Comparative Examples 1-3 was measured. The measurement was carried out in accordance with JIS A1901, "Measurement method for the emission of volatile organic compounds (VOC), formaldehyde and other carbonyl compounds in building materials-Small chamber method". A gas chromatograph mass spectrometer (trade name “TurboMatrix ATD, TurboMass Gold” manufactured by PERKINELMER) was used for VOC analysis. The total VOC peak area detected in the range from n-Hexane to n-Hexadecane was converted to Toluene to determine the VOC emission rate (TVOC: μg / m ² · hr).

  The results are shown in Table 2.

  From Table 2, it can be seen that the wallpaper of Examples 1 and 2 has an extremely low VOC emission rate compared to the wallpaper of Comparative Examples 1 to 3. This means that the wallpaper of Examples 1 and 2 has a very low VOC release compared to the wallpapers of Comparative Examples 1 to 3.

  The wallpaper of Example 2 has a higher VOC release rate than the wallpaper of Example 1 because organic ink was used to form the pattern layer.

Test Example 2 (Antistatic performance)
For the wallpaper of Examples 1-2 and Comparative Examples 1-3, the surface resistance value was measured in accordance with JISK6911. For the measurement, an electrode for a flat plate (trade name “SME8310” manufactured by TOA) and a digital superinsulator (trade name “DMS-8103” manufactured by TOA) were used.

  The measurement results are shown in Table 2.

  From Table 2, it can be seen that all the wallpaper has a surface resistance value of the 11th power or less and has antistatic performance.

Claims (5)

A wallpaper for a clean room which does not contain a vinyl chloride resin, and is formed by sequentially laminating an adhesive layer, a polyolefin non-foamed resin layer, and a protective layer 1 on a paper substrate. The wallpaper for a clean room according to claim 1, wherein the protective layer 1 contains an antistatic agent. The clean room wallpaper according to claim 1, wherein a protective layer 2 is further laminated on the protective layer 1. The wallpaper for a clean room according to claim 3, further comprising a pattern layer between the protective layer 1 and the protective layer 2. The wallpaper for a clean room according to claim 3 or 4, wherein the protective layer 2 contains an antistatic agent.