JP2017177685A - Moisture-proof film for housing material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a moisture-proof film that can be used at a door, a sliding door, a partition, a flooring material, etc., where there is a wide difference in a temperature and humidity environment on both sides, the moisture-proof film having improved hot press resistance with no deterioration in barrier properties by tension or hot press when bonded onto a housing material or a decorative laminate.SOLUTION: A moisture-proof film for a housing material includes a primer layer, a resin substrate, an inorganic layer, a barrier coat layer and a primer layer in this order. The barrier coat layer has nanoindentation hardness of 0.4-2.5 GPa.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a moisture-proof film for building materials, and more particularly to a moisture-proof film for building materials provided with an adhesion primer layer, a building material provided with the moisture-proof film for building materials, and a decorative board provided with the building material.

  Conventionally, a decorative board in which a decorative sheet is laminated on the surface of a wood-based substrate such as wood plywood, medium density fiberboard (MDF), hard board, particle board, etc., is used as a surface material for doors, sliding doors, partitions, flooring, etc. It is used. If the moisture content of the wooden base material is smaller than the equilibrium moisture content of the wooden base material under the outside air condition, moisture absorption or water absorption is performed from the surface of the decorative board where the decorative sheet is not laminated, and this surface is expanded. . On the other hand, when the moisture content of the wooden base material is higher than the equilibrium moisture content of the wooden base material under the outside air condition, the surface of the laminated decorative sheet is absorbed and released while it is shrunk by moisture release or water discharge. Since there is almost no moisture or moisture absorption / extraction, the surface of the decorative board laminated with the decorative sheet has a different expansion rate or contraction rate from the surface where the wooden base material is exposed, and the decorative board is warped, resulting in a commercial value. Result in dropping.

  As a method for preventing such warping of the woody base material, for example, a method of sufficiently reinforcing the decorative plate so as not to be warped with metal or the like, or on the back side of the decorative plate in which a decorative sheet is laminated on the surface In order to prevent the permeation of water vapor that causes the moisture content of the wood-based substrate to change due to moisture absorption and desorption from the back side of the decorative board, a method of applying paint, or a decorative board with a decorative sheet laminated on the surface A method of laminating a film made of a synthetic resin such as vinyl chloride, polyethylene, or polypropylene or a method of laminating a moisture-proof film is known.

  The above-described method of reinforcing the decorative plate can prevent warping by reinforcing, but it cannot prevent warping in the case of a structure such as a flash door that cannot be sufficiently reinforced. In addition, the method of painting a paint has a problem that it is difficult to form a uniform moisture-proof and waterproof layer due to strong suction of the paint on the surface of the wooden base material and poor surface smoothness. there were. Therefore, since a warp can be prevented to some extent, a method of laminating a synthetic resin film or a moisture-proof film is adopted and widely used.

  However, even if it is a decorative board that adopts a method of attaching a moisture-proof film, if it is used for a long time on doors, sliding doors, partitions, flooring, etc. that have a large difference in temperature and humidity environment on both sides, There is a difference in the moisture distribution of the substrate between the one surface side and the other surface side. As a result, the degree of expansion or contraction is different on both surfaces, and warping may occur. In some cases, moisture resistance may be reduced by tensile force, heat, or press when the moisture-proof film is bonded to a wooden substrate or the like. Therefore, further improvement is still desired about the adhesive strength of such a moisture-proof film and a decorative board.

  Here, as a packaging material used for packaging foods, pharmaceuticals, and the like, a laminate having excellent gas barrier properties is known (see Patent Documents 1 to 3). Patent Documents 1 to 3 propose using a laminate in which a gas barrier coating layer having a film hardness of 3.0 to 20.0 GPa is laminated. However, since the required performances such as technical fields and durability are greatly different between packaging materials and building materials, it has been difficult to employ a laminate in which such a gas barrier coating layer is laminated as a moisture-proof film for building materials.

JP-A-2005-74642 JP 2005-74731 A JP 2007-168085 A

  The present invention has been made in view of the above-mentioned background art, and its purpose can be used for doors, sliding doors, partitions, flooring, etc. that have large differences in temperature and humidity environments on both sides, and for building materials and decorative boards. It is an object of the present invention to provide a moisture-proof film having improved heat-resistant pressability without lowering barrier properties even by tensioning or hot pressing during lamination.

  As a result of intensive studies to solve the above problems, the present inventors have found that the above problems can be solved by adjusting the nanoindentation hardness of the barrier coat layer formed between the inorganic layer and the primer layer. Thus, the present invention has been completed.

That is, according to one aspect of the present invention,
A moisture-proof film for building materials comprising a resin base material, an inorganic layer, a barrier coat layer, and a primer layer in this order,
There is provided a moisture-proof film for building materials, wherein the barrier coating layer has a nanoindentation hardness of 0.4 GPa or more and 2.5 GPa or less.

  In the aspect of the present invention, the barrier coat layer is preferably a cured film of a hydrolysis product of a metal alkoxide and a water-soluble polymer.

  In the aspect of the present invention, the primer layer is preferably a two-component curable urethane resin layer.

  In the aspect of this invention, it is preferable that the said inorganic layer is a vapor deposition film | membrane of an inorganic substance or an inorganic oxide.

  In the aspect of the present invention, it is preferable that a second primer layer is further provided on the surface of the resin substrate opposite to the inorganic layer.

In the aspect of the present invention, the moisture permeability film measured in accordance with JISK7126-2 is 0.5 g / m ² or less after the moisture-proof film for building materials is pressed at 110 ° C. under a pressure of 70 kg / cm ² for 3 seconds. It is preferable.

In the embodiment of the present invention, the moisture permeability film measured according to JIS K 716-2 is 0.5 g / m ² after stretching the moisture-proof film for building materials to a stretching ratio of 2.0% in an environment of 90 ° C. The following is preferable.

According to another aspect of the invention,
A wood-based substrate;
A building material provided with the moisture-proof film for building material described above on one side or both sides of the woody base material is provided.

According to another aspect of the invention,
The above building materials,
A decorative board provided with a decorative sheet on one side or both sides of the building material is provided.

  In the present invention, it can be used for doors, sliding doors, partitions, flooring, etc., which have a large difference in temperature and humidity environment on both sides. Thus, a moisture-proof film with improved heat-resistant pressability can be provided.

It is a schematic cross section which shows one Embodiment of the moisture proof film for building materials by this invention. It is a schematic cross section which shows one Embodiment of the building materials by this invention. It is a schematic cross section which shows one Embodiment of the decorative board by this invention. It is a schematic cross section which shows one Embodiment of the decorative board by this invention.

<Moisture-proof film for building materials>
The moisture-proof film for building materials according to the present invention includes a resin base material, an inorganic layer, a barrier coat layer, and a primer layer in this order, and further includes a second primer layer on the surface opposite to the inorganic layer of the resin base material. preferable. Such a moisture-proof film for building materials is highly moisture-proof and has high adhesion to the wooden base material due to the primer layer, so it is suitable for doors, sliding doors, partitions, flooring, etc. that have large differences in temperature and humidity environments on both sides Can be used for

The moisture-proof film for building materials preferably has a moisture permeability of 0.5 g / m ² or less measured according to JIS K 716-2. If the moisture permeability is 0.5 g / m ² or less, sufficient moisture resistance can be exhibited. The moisture permeability is measured using a water vapor permeability measuring device (a measuring machine manufactured by MOCON [model name: PERMATRAN 3/33]) so that the humidity adjustment side becomes the barrier coat layer side. It can be measured by setting a moisture-proof film.

The moisture-proof film for building material is preferably pressed at 110 ° C. under a pressure of 70 kg / cm ² for 3 seconds, and then has a moisture permeability of 0.5 g / m ² or less measured according to JISK7126-2, 0.4 g / M ² or less is more preferable. If the moisture permeability measured in this way is 0.5 g / m ² or less, moisture resistance can be maintained even after the press treatment performed during processing of the decorative plate.

The moisture-proof film for building materials preferably has a moisture permeability of 0.5 g / m ² or less measured according to JIS K 716-2-2 after stretching to a stretching ratio of 2.0% in an environment of 90 ° C., More preferably, it is 0.4 g / m ² or less. If the moisture permeability measured in this way is 0.5 g / m ² or less, moisture resistance can be maintained even after the stretching treatment performed during processing into a decorative plate.

  A schematic cross-sectional view of a moisture-proof film for building materials according to the present invention is shown in FIG. A building material moisture-proof film 10 shown in FIG. 1 includes a second primer layer 1 on one surface of a resin base material 2 and an inorganic layer 3, a barrier coat layer 4, and a primer layer 5 in this order on the other surface. Hereinafter, each layer which comprises the moisture proof film for building materials is demonstrated.

(Resin base material)
The resin base material of the moisture-proof film is not particularly limited, and a conventionally known resin film or resin sheet can be used. Examples of the resin film or resin sheet include polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyamide resin 6, polyamide resin 66, polyamide resin 610, polyamide resin 612, polyamide resin 11, and polyamide. Examples thereof include polyamide resins such as resin 12, and polyolefin resins such as α-olefin polymers such as polyethylene and polypropylene.

  The resin film or resin sheet used for the resin base material is, for example, one or more of the above-mentioned resins, and is formed into a film such as an extrusion method, cast molding method, T-die method, cutting method, inflation method, and others The above-mentioned resin is used alone or in a multilayer co-extrusion method using two or more kinds of resins to form a film, and further, two or more kinds of resins are used and mixed before forming a film. Then, it can be manufactured by a method of forming a film. Further, for example, a film that is stretched in a uniaxial or biaxial direction using a tenter system or a tubular system can be used.

  When using one or more of the above resins and forming the film, for example, film processability, heat resistance, weather resistance, mechanical properties, dimensional stability, antioxidant properties, slipperiness, releasability, Various plastic compounding agents and additives can be added for the purpose of improving and modifying flame retardancy, antifungal properties, electrical characteristics, strength, etc. Can be arbitrarily added depending on the purpose.

  As general additives, for example, a lubricant, a crosslinking agent, an antioxidant, an ultraviolet absorber, a light stabilizer, a filler, a reinforcing agent, an antistatic agent, a pigment, and the like can be used. Also, a modifying resin or the like can be used.

  The thickness of the resin film or resin sheet used for the resin substrate is not particularly limited, and any thickness can be used as long as it can be pre-processed or film-formed when forming a vapor-deposited film. From the viewpoints of property, form retentivity, transportability, etc., a range of 6 to 400 μm, preferably 12 to 200 μm is desirable.

(Inorganic layer)
The inorganic layer of the moisture-proof film is preferably a deposited film of an inorganic substance or an inorganic oxide. A vapor deposition film can be formed by a conventionally known method using a conventionally known inorganic substance or inorganic oxide, and its composition and formation method are not particularly limited. Since the moisture-proof film has an inorganic layer, gas barrier properties that prevent permeation of oxygen gas, water vapor, and the like can be improved.

  Examples of the deposited film include silicon (Si), aluminum (Al), magnesium (Mg), calcium (Ca), potassium (K), tin (Sn), sodium (Na), boron (B), and titanium (Ti). ), Lead (Pb), zirconium (Zr), yttrium (Y) and other inorganic or inorganic oxide vapor deposition films can be used. In particular, as a material suitable for building materials and the like, it is preferable to use a vapor-deposited film of aluminum metal, or a vapor-deposited film of silicon oxide or aluminum metal or aluminum oxide. Moreover, a transparent inorganic oxide vapor deposition layer is more preferable when a moisture-proof film and wood are bonded using high frequency during flash door processing.

Representation of the inorganic oxide, for _example, SiO X, as such AlO _X MO _X (In the formula, M represents an inorganic element, the value of X, varies each of an inorganic element range.) In expressed. As a range of the value of X, silicon (Si) is 0 to 2, aluminum (Al) is 0 to 1.5, magnesium (Mg) is 0 to 1, calcium (Ca) is 0 to 1, 0 to 0.5 for potassium (K), 0 to 2 for tin (Sn), 0 to 0.5 for sodium (Na), 0 to 1,5 for boron (B), titanium (Ti) Can take values in the range of 0 to 2, lead (Pb) in the range of 0 to 1, zirconium (Zr) in the range of 0 to 2, and yttrium (Y) in the range of 0 to 1.5. In the above, when X = 0, it is a complete inorganic simple substance (pure substance) and is not transparent, and the upper limit of the range of X is a completely oxidized value. For building materials, silicon (Si) and aluminum (Al) are preferably used. Silicon (Si) has a value in the range of 1.0 to 2.0, and aluminum (Al) has a value in the range of 0.5 to 1.5. Can be used.

  In the present invention, the film thickness of the inorganic or inorganic oxide vapor-deposited film as described above varies depending on the type of inorganic or inorganic oxide used, but is, for example, about 50 to 2000 mm, preferably about 100 to 1000 mm. It is desirable to select and form arbitrarily within the range. More specifically, in the case of an aluminum deposited film, a film thickness of about 50 to 600 mm, more preferably about 100 to 450 mm, is desirable, and in the case of an aluminum oxide or silicon oxide deposited film, The film thickness is about 50 to 500 mm, more preferably about 100 to 300 mm.

  As a method for forming a vapor deposition film, for example, a physical vapor deposition method (Physical Vapor Deposition method, PVD method) such as a vacuum vapor deposition method, a sputtering method, and an ion plating method, or a plasma chemical vapor deposition method, a thermochemical method, or the like. Examples thereof include a chemical vapor deposition method (chemical vapor deposition method, CVD method) such as a vapor phase growth method and a photochemical vapor deposition method.

(Barrier coat layer)
The barrier coat layer of the moisture-proof film is a layer having gas barrier properties, and is preferably a coating film. The nanoindentation hardness of the barrier coat layer is 0.4 GPa or more and 2.5 GPa or less, preferably 0.5 GPa or more and 2.2 GPa or less, more preferably 0.8 GPa or more and 2.1 GPa or less, and further preferably 0. It is 9 GPa or more and 1.6 GPa or less. If the barrier coating layer has a nano-indentation hardness of 0.4 GPa or more, gas barrier properties are sufficiently developed, and if the nano-indentation hardness is 2.5 GPa or less, deterioration of the barrier properties due to cracks in the barrier coating layer is suppressed. In addition, environmental durability performance, heat resistant pressability at the time of decorative plate processing and stretchability of the film are improved. The nanoindentation hardness of the barrier coat layer can be controlled by adjusting the drying temperature and drying time when the barrier coat layer (coating film) is formed. In addition, the nanoindentation hardness of the barrier coat layer is a microtome for producing a cut section of a moisture-proof film, and a nanoindentation device (manufactured by HYSITRON, Inc., trade name: Triboindenter TI950 TriboIndenter) from the cross section (side surface) side. It can be measured by an indentation test using a diamond triangular pyramid indenter by a load control method (max load: 15 μN).

The barrier coat layer is preferably a cured film of a hydrolysis product of a metal alkoxide and a water-soluble polymer. The barrier coat layer can be formed by, for example, the following gas barrier coating film. The coating film is a coating film that retains gas barrier properties in a high-temperature and high-humidity environment, and has a general formula R ¹ _n M (OR ² ) _m (where R ¹ and R ² have 1 to 8 carbon atoms) M represents a metal atom, n represents an integer of 0 or more, m represents an integer of 1 or more, and n + m represents the valence of M. It comprises one or more metal alkoxides and a water-soluble polymer, and further comprises a gas barrier composition obtained by polycondensation by a sol-gel method in the presence of a sol-gel method catalyst, an acid, water, and an organic solvent. It is a coating film. The composition is applied onto the vapor deposition film on the vapor deposition film to provide a coating film, and is heat-dried at a temperature of 20 ° C. to 180 ° C. and below the melting point of the vapor deposition film for 10 seconds to 10 minutes. Can be formed.

  In addition, the gas barrier composition is applied onto the deposited film on the base film, and two or more coating films are stacked, at a temperature of 20 ° C. to 180 ° C. and below the melting point of the base film. You may heat-dry for 10 seconds-10 minutes, and you may form the composite polymer layer which laminated | stacked two or more gas barrier coating films.

In the metal alkoxide, examples of the metal atom represented by M in the general formula R ¹ _n M (OR ² ) _m include silicon, zirconium, titanium, aluminum, and the like.

  In the present invention, two or more of the alkoxides may be used in combination. For example, when alkoxysilane and zirconium alkoxide are mixed and used, the toughness, heat resistance and the like of the resulting gas barrier laminate film can be improved, and a decrease in the retort resistance of the film during stretching can be avoided. Moreover, when alkoxysilane and titanium alkoxide are mixed and used, the heat conductivity of the gas barrier coating film obtained will become low, and heat resistance will improve remarkably.

  As the water-soluble polymer used in the present invention, a polyvinyl alcohol resin or an ethylene / vinyl alcohol copolymer can be used alone, respectively, or a polyvinyl alcohol resin and an ethylene / vinyl alcohol copolymer can be used. It can be used in combination with coalescence. In the present invention, physical properties such as gas barrier properties, water resistance, weather resistance, and the like can be remarkably improved by using a polyvinyl alcohol resin and / or an ethylene / vinyl alcohol copolymer.

  As the polyvinyl alcohol resin, those obtained by saponifying polyvinyl acetate can be generally used. Polyvinyl alcohol resins include partially saponified polyvinyl alcohol resins in which several tens of percent of acetate groups remain, completely saponified polyvinyl alcohols in which no acetate groups remain, and modified polyvinyl alcohol resins in which OH groups have been modified. Well, not particularly limited.

  As the ethylene / vinyl alcohol copolymer, a saponified product of a copolymer of ethylene and vinyl acetate, that is, a product obtained by saponifying an ethylene-vinyl acetate random copolymer can be used. For example, it is not particularly limited, and includes a partially saponified product in which several tens mol% of acetic acid groups remain to a complete saponified product in which only several mol% of acetic acid groups remain or no acetic acid groups remain. However, it is preferable to use a saponification degree that is preferably 80 mol% or more, more preferably 90 mol% or more, and still more preferably 95 mol% or more from the viewpoint of gas barrier properties. In addition, the content of the repeating unit derived from ethylene in the ethylene / vinyl alcohol copolymer (hereinafter also referred to as “ethylene content”) is usually 0 to 50 mol%, preferably 20 to 45 mol%. It is preferable.

  In the present invention, a silane coupling material may be added to the barrier coat layer. For example, a silane coupling material having a reactive group such as an alkoxy group such as a methoxy group or an ethoxy group, an acetoxy group, an amino group, or an epoxy group can be used.

  The barrier coat layer can be produced by the following method. First, the above-described metal alkoxide, if necessary, a silane coupling agent, a water-soluble polymer, a sol-gel method catalyst, an acid, water, an organic solvent, and the like are mixed to prepare a gas barrier composition.

  Next, the gas barrier composition is applied onto the deposited film on the deposited film by a conventional method and dried. By this drying step, polycondensation of the metal alkoxide, the silane coupling agent, the polyvinyl alcohol resin and / or the ethylene / vinyl alcohol copolymer further proceeds, and a coating film is formed. On the first coating film, the above coating operation may be further repeated to form a plurality of coating films composed of two or more layers.

  Next, the base film coated with the gas barrier composition is heat-treated at a temperature of 20 ° C. to 180 ° C. and below the melting point of the deposited film, preferably 50 ° C. to 160 ° C. for 10 seconds to 10 minutes. To do. Thereby, a barrier film having a barrier coat layer in which one or more gas barrier coating films of the gas barrier composition are formed on the vapor deposition film can be produced.

  As a method of applying the gas barrier composition of the present invention described above, for example, once by a coating means such as a roll coat such as a gravure roll coater, spray coat, spin coat, dipping, brush, barcode, applicator or the like A coating film having a dry film thickness of 0.01 to 30 μm, preferably about 0.1 to 10 μm, can be formed by applying a plurality of times. Further, under a normal environment, 50 to 300 ° C., preferably By performing heating and drying at a temperature of 70 to 200 ° C. for 0.005 to 60 minutes, preferably 0.01 to 10 minutes, condensation is performed and a gas barrier coating film can be formed.

(Primer layer)
The primer layer of the moisture-proof film for building materials is provided in order to obtain sufficient adhesive strength when the barrier coat layer and the wooden board or the like are bonded via an adhesive layer. The primer layer can be formed using, for example, an ester resin, a urethane resin, an acrylic resin, a polycarbonate resin, a vinyl chloride-vinyl acetate copolymer, a polyvinyl butyral resin, a nitrocellulose resin, One or more of these resins can be used. Among them, the formation of a two-component curable urethane resin layer comprising a mixed resin of a urethane resin and a nitrocellulose-based resin as a main agent and an isocyanate compound as a curing agent is particularly preferable.

  The thickness of the primer layer is preferably 0.1 μm to 3 μm, more preferably 0.2 μm to 1 μm, and still more preferably 0.3 μm to 0.9 μm. As a method for providing the primer layer, it can be formed by using a coating means such as roll coating or gravure printing. Since such a primer layer is excellent in adhesion to a woody base material, the moisture-proof film of the present invention can be suitably used for doors, sliding doors, partitions, flooring, etc. that have large differences in temperature and humidity environments on both sides. . The primer layer on the back surface side (second primer layer) in contact with the resin substrate and the primer layer on the surface side in contact with the barrier coat layer may have the same composition or different compositions. .

<Building materials>
The building material according to the present invention is provided with the above moisture-proof film for building materials on one side or both sides of the wood-based substrate, and an adhesive layer may be provided between the moisture-proof film for building material and the wooden substrate. Such building materials are highly moisture-proof and have high adhesion between the moisture-proof film primer layer and the wood-based substrate, making them suitable for doors, sliding doors, partitions, flooring, etc. that have a large difference in temperature and humidity environment on both sides. Can be used for In addition, the primer layer (second primer layer) on the back side provided on the surface opposite to the barrier coat layer of the resin base material is used when the resin base material and a decorative sheet or a wooden board are bonded via an adhesive layer. This further increases the adhesive strength.

  A schematic cross-sectional view of a building material according to the present invention is shown in FIG. A building material 20 shown in FIG. 2 is obtained by laminating a moisture-proof film for building material 10 and a wooden base material 11 with an adhesive layer 12 interposed therebetween. Hereinafter, each layer constituting the building material will be described. The building material moisture-proof film is as described above.

(Woody base material)
The woody base material for building materials is not particularly limited, and conventionally known materials can be used. Examples of the wood-based substrate include plywood, particle board (PB), medium density fiber board (MDF), and high density fiber board (HDF).

(Adhesive layer)
The adhesive layer of the building material is not particularly limited, and a conventionally known adhesive for building materials can be used. Examples of the adhesive include one-part or two-part cured or non-cured vinyl, (meth) acrylic, polyamide, polyester, polyether, polyurethane, epoxy, rubber, etc. And an adhesive for laminating such as a solvent type, an aqueous type, and an emulsion type. Examples of the coating method for the adhesive include a direct gravure roll coating method, a gravure roll coating method, a kiss coating method, a reverse roll coating method, a fountain method, a transfer roll coating method, and other methods. As the coating ^{amount, 0.1g / m 2 ~10g / m} 2 ( dry state) position are ^{preferred, 1g / m 2 ~5g / m} 2 ( dry state) position is more preferred.

<Decorative board>
The decorative board according to the present invention includes a decorative sheet on one or both surfaces of the building material, and an adhesive layer may be provided between the building material and the decorative sheet. Such a decorative board is highly moisture-proof and has high adhesion between the primer layer of the moisture-proof film and the wooden base material, so it can be used for doors, sliding doors, partitions, flooring, etc. that have large differences in temperature and humidity environments on both sides. It can be suitably used.

  3 and 4 are schematic cross-sectional views of a decorative board according to the present invention. The decorative board 30 shown in FIG. 3 has a moisture-proof film 10 for building material laminated on one surface of a wood-based substrate 11 via an adhesive layer 12, and a decorative sheet 13 laminated on the other surface of the wooden-based substrate 11. It has been done. Further, the decorative board 30 shown in FIG. 4 has a moisture-proof film for building material 10 laminated on both surfaces of the wood-based substrate 11 via an adhesive layer 12, and a decorative sheet is attached to the moisture-proof film for building material 10 on one side. It is a laminated one. Hereinafter, each layer which comprises a decorative board is demonstrated. The building material and the adhesive layer are as described above.

(Decorative sheet)
The decorative sheet of the decorative plate is not particularly limited, and conventionally known decorative sheets can be used. Examples of the decorative sheet include a decorative sheet made of a paper base material or a synthetic resin base material on which a pattern printing made of a wood grain pattern is applied.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. However, the present invention is not limited to the following examples.

[Example 1]
An aluminum oxide (alumina) film having a thickness of 10 nm was formed on one side of a PET film (unit: PET-F made by Unitika) having a thickness of 12 μm, which is a resin substrate, by vacuum deposition.

  Here, a preliminarily prepared hydrolyzate having a solid content of 4% by mass composed of tetraethoxysilane (ethyl silicate 40), hydrochloric acid, isopropyl alcohol, and ion-exchanged water was stirred. Furthermore, a liquid mixture prepared in advance comprising an aqueous polyvinyl alcohol solution, isopropyl alcohol and ion exchange water was added and stirred to obtain a colorless and transparent composition for forming a barrier coat layer.

  Subsequently, the barrier coat layer forming composition is coated on the inorganic layer (alumina film) of the PET film by the gravure roll coating method, and then the nanoindentation hardness of the barrier coat layer is 1.2 GPa. And dried to form a barrier coat layer having a thickness of 200 nm.

  Furthermore, on the barrier coat layer, a two-component curable urethane resin composition in which an isocyanate as a curing agent is added to a urethane resin / nitrocellulose resin as a main agent is applied by a gravure printing method, and a thickness of 0.3 μm is applied. A primer layer was formed. Also, after the corona treatment discharge is applied to the surface opposite to the inorganic layer of the PET film, a two-component curable urethane resin composition in which an isocyanate as a curing agent is added to a urethane resin / nitrocellulose resin as a main agent is applied. Then, a second primer layer having a thickness of 0.3 μm was formed to obtain a moisture-proof film (layer structure: second primer layer / resin substrate / inorganic layer / barrier coat layer / primer layer). After aging the moisture-proof film, a cut section of the moisture-proof film was prepared with a microtome. Subsequently, in the indentation test using a diamond indentation-shaped indenter with a load control method (max load: 15 μN) using a nanoindentation device (manufactured by HYSITRON, USA, trade name: triboindenter TI950 TriboIndenter), It was 1.2 GPa when the nanoindentation hardness of the barrier coat layer was measured from the cross section (side face) side.

[Example 2]
A moisture-proof film was produced in the same manner as in Example 1 except that the barrier coating layer was heat-dried and cured to have a nanoindentation hardness of 0.5 GPa to form a barrier coating layer having a thickness of 200 nm. . After aging the moisture-proof film, the nanoindentation hardness of the barrier coat layer was measured in the same manner as in Example 1 and found to be 0.5 GPa.

[Example 3]
A moisture-proof film was produced in the same manner as in Example 1 except that the barrier coating layer was heat-dried and cured to have a nanoindentation hardness of 2.1 GPa to form a barrier coating layer having a thickness of 200 nm. . After aging the moisture-proof film, the nanoindentation hardness of the barrier coat layer was measured in the same manner as in Example 1 and found to be 2.1 GPa.

[Comparative Example 1]
A moisture-proof film was prepared in the same manner as in Example 1 except that the barrier coat layer was heat-dried and cured to have a nanoindentation hardness of 0.3 GPa to form a barrier coat layer having a thickness of 200 nm. . After aging the moisture-proof film, the nanoindentation hardness of the barrier coat layer was measured in the same manner as in Example 1 and found to be 0.3 GPa.

[Comparative Example 2]
A moisture-proof film was produced in the same manner as in Example 1 except that the barrier coating layer was heat-dried and cured to have a nanoindentation hardness of 2.7 GPa to form a barrier coating layer having a thickness of 200 nm. . After aging the moisture-proof film, the nanoindentation hardness of the barrier coat layer was measured in the same manner as in Example 1 and found to be 2.7 GPa.

<Measurement of moisture permeability>
The moisture permeability was measured under the following conditions using the moisture-proof films prepared in the above Examples and Comparative Examples.
(1) Using a water vapor transmission rate measuring device (a measuring machine manufactured by MOCON [model name, PERMATRAN 3/33]), the humidity control side is the barrier coat layer side before treatment. A moisture-proof film was set, and the moisture permeability was measured under the condition of a temperature of 40 ° C. and a humidity of 90% in accordance with JIS K 716-2.
(2) Set the moisture-proof film in a tensile tester (A & D Co., Ltd. Tensilon) and stretch the moisture-proof film to a stretch rate of 2.0% in an environment of 90 ° C or 110 ° C. (3) The moisture-proof film was pressed at 110 ° C. or 130 ° C. with a double hydraulic molding machine at a pressure of 70 kg / cm ² for 3 seconds, and the moisture permeability was measured in the same manner.

The measurement results are shown in Table 1.

DESCRIPTION OF SYMBOLS 1 2nd primer layer 2 Resin base material 3 Inorganic layer 4 Barrier coat layer 5 Primer layer 10 Moisture-proof film for building materials 11 Wood type base material 12 Adhesive layer 13 Cosmetic sheet 20 Building material 30 Decorative plate

Claims (9)

A moisture-proof film for building materials comprising a resin base material, an inorganic layer, a barrier coat layer, and a primer layer in this order,
A moisture-proof film for building materials, wherein the barrier coating layer has a nanoindentation hardness of 0.4 GPa to 2.5 GPa.   The moisture-proof film for building materials according to claim 1, wherein the barrier coat layer is a cured film of a hydrolysis product of a metal alkoxide and a water-soluble polymer.   The moisture-proof film for building materials according to claim 1 or 2, wherein the primer layer is a two-component curable urethane resin layer.   The moisture-proof film for building materials as described in any one of Claims 1-3 whose said inorganic layer is a vapor deposition film of an inorganic substance or an inorganic oxide.   The moisture-proof film for building materials as described in any one of Claims 1-4 further equipped with the 2nd primer layer in the surface on the opposite side to the said inorganic layer of the said resin base material. The moisture permeability measured according to JISK7126-2 is 0.5 g / m ² or less after the moisture-proof film for building materials is pressed at 110 ° C. and a pressure of 70 kg / cm ² for 3 seconds, and the moisture permeability is 0.5 g / m ² or less. The moisture-proof film for building materials according to any one of the above. The moisture permeability measured according to JIS K 7126-2 is 0.5 g / m ² or less after the moisture-proof film for building materials is stretched to a stretching ratio of 2.0% in an environment of 90 ° C. The moisture-proof film for building materials as described in any one of -5. A wood-based substrate;
Building material provided with the moisture-proof film for building materials as described in any one of Claims 1-7 on the single side | surface or both surfaces of the said wood type base material. The building material according to claim 8;
A decorative board comprising a decorative sheet on one or both surfaces of the building material.

Images