JP6780231B2 - Moisture-proof sheet for building materials - Google Patents

Description

The present invention relates to a moisture-proof sheet for building materials, which is attached to a wooden base material or the like constituting a fitting or other building material such as a door panel.

For decorative boards such as indoor door panels, the surface of the wood-based base material that constitutes the decorative board is used to prevent warping of the base material caused by moisture absorption and desorption due to changes in temperature and humidity in the indoor atmosphere. A moisture-proof sheet may be attached to the surface.
That is, the decorative board improves the solid printing layer and designability for imparting concealment to the surface of, for example, plywood, medium density fiberboard (MDF), veneer board, board material, and other multi-layered wood-based base materials. It is composed by laminating decorative sheets printed with a pattern-like layer for making them. Then, in order to prevent deformation (warp, dimensional change) due to temperature and humidity, these decorative boards are known to have a method of applying paint to the surface of a wood-based base material or attaching a moisture-proof sheet. (Patent Document 1).

Japanese Patent No. 4946350

An object of the present invention is a moisture-proof sheet that suppresses warpage of a pasted decorative board and has designability against the influence of changes in environmental temperature and humidity.

In order to solve the problem, the moisture-proof sheet for building materials according to one aspect of the present invention has a base material layer made of a thermoplastic resin film and a printing layer provided on one surface side of the base material layer. The sheet is characterized in that the water vapor permeability is 3.0 g / m ² · day or less.

According to the moisture-proof sheet according to the aspect of the present invention, the water vapor permeability is 3.0 g / m ² , day, atm or less, so that it has moisture-proof performance, and since it has a printed layer, it has designability.

It is sectional drawing which shows the structural example of the moisture-proof sheet which concerns on embodiment based on this invention.

Next, an embodiment of the present invention will be described with reference to the drawings.
Here, the drawings are schematic, and the relationship between the thickness and the plane dimension, the ratio of the thickness of each layer, and the like are different from the actual ones. Further, the embodiments shown below exemplify a configuration for embodying the technical idea of the present invention, and the technical idea of the present invention describes the material, shape, structure, etc. of the constituent parts as follows. It is not specific to the thing. The technical idea of the present invention may be modified in various ways within the technical scope specified by the claims stated in the claims.

In the moisture-proof sheet 1 for building materials of the present embodiment, as shown in FIG. 1, a vapor deposition layer 3 made of an inorganic oxide and a printing layer 4 are provided in this order on the surface of a base material layer 2 made of a synthetic resin. Further, adhesion auxiliary processing portions 5 and 6 are formed on both the front and back surfaces of the moisture-proof sheet 1, respectively.
Further, the print layer 4 does not need to be formed on the entire surface of the vapor deposition layer 3. In that case, the surface portion of the vapor deposition layer 3 where the print layer 4 is not formed constitutes a part of the surface of the moisture-proof sheet 1.
Further, each layer is preferably transparent. Here, the term "transparent" refers to transparency such that the back side can be visually recognized from the front side, and the transparency of the entire moisture-proof sheet 1 so that the front side to the back side can be visually recognized.

Examples of the material of the base material layer 2 made of the thermoplastic resin include polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl alcohol copolymer, olefin-based thermoplastic resin such as a mixture thereof, polyethylene terephthalate, and poly. Ester-based thermoplastic resins such as butylene terephthalate, polyethylene naphthalate, polyethylene naphthalate-isophthalate copolymer, polycarbonate, polyarylate, and acrylic heat such as methyl polymethacrylate, ethyl polymethacrylate, butyl polyacrylate, etc. Examples thereof include plastic resins and non-halogen thermoplastic resins such as polyethylene, polyurethane, polystyrene and acrylonitrile-butadiene-styrene resins.

The base material layer 2 may be a sheet stretched in the uniaxial or biaxial direction or may not be stretched, but when the vapor deposition layer 3 is formed on one surface, the mechanical strength is strong and the dimensions are large. A sheet stretched in the biaxial direction is preferable because of its excellent stability. The thickness of the base material layer 2 is, for example, in the range of 9 to 100 μm. For example, the base material layer 2 is preferably a biaxially stretched polyethylene terephthalate film, and the film constituting the base material layer 2 is transparent.
The thin-film deposition layer 3 is made of a thin film of an inorganic oxide typified by silicon oxide, magnesium oxide, and aluminum oxide.

The thin-film deposition layer 3 may be an inorganic vapor-deposited layer made of a metal thin film typified by aluminum, but in the case of the inorganic thin-film deposition layer, it has a metallic luster. On the other hand, in the case of an inorganic oxide vapor deposition layer, a transparent vapor deposition film can be used.
Optimal conditions for the thickness of the vapor-deposited layer 3 differ depending on the type and composition of the inorganic compound used, but generally it is preferably in the range of 5 to 300 nm, and the value is appropriately selected. However, if the film thickness is less than 5 nm, a uniform film may not be obtained or the film thickness may not be sufficient, and the function as the moisture-proof sheet 1 may not be sufficiently fulfilled. Further, when the film thickness exceeds 300 nm, the flexibility cannot be maintained due to the residual stress of the thin film, and there is a problem that the thin film may be cracked due to an external factor after the film formation. More preferably, it is in the range of 10 to 150 nm.

As a method of laminating the vapor deposition layer 3 on the base material layer 2, a vacuum vapor deposition method, a sputtering method, an ion plating method, a plasma vapor deposition method (CVD), or the like can be used. However, considering productivity, the vacuum deposition method is the best. As the heating means of the vacuum vapor deposition method, it is preferable to use any of an electron beam heating method, a resistance heating method, and an induction heating method, but considering the wide range of selectivity of the evaporative material, the electron beam heating method or resistance heating method is used. It is more preferable to use the method. Further, in order to improve the adhesion between the vapor deposition layer 3 and the base material layer 2 and the denseness of the vapor deposition layer 3, the vapor deposition can also be performed by using a plasma assist method or an ion beam assist method. Further, in order to increase the transparency of the vapor-deposited film, reaction vapor deposition in which various gases such as oxygen are blown into the vapor deposition may be used.

The print layer 4 is a layer on which a figure or characters showing a usage procedure are given to the moisture-proof sheet, or a pattern for giving a high-class feeling is given.
The printing layer 4 is not particularly limited as a printing ink that can be provided by using a known printing method, but an ink corresponding to the printing method can be appropriately selected. In particular, it is preferable to select it in consideration of adhesion to the resin base material layer 2 or the vapor deposition layer, printability, and weather resistance as the building material to be applied.
If necessary, an adhesive layer (not shown) may be provided between the printing layer 4 and the base material layer 2 or the vapor deposition layer 3 for the purpose of improving the adhesiveness. The resin used for this adhesive layer (not shown) is not particularly limited, but for example, a two-component curable urethane resin or the like can be used, and for example, a coating device or a gravure printing device can be used to provide the resin.

The adhesion auxiliary treatment units 5 and 6 provide a method of forming the adhesion auxiliary treatment parts 5 and 6 by physically modifying the surface roughness of the layer to be formed to improve the wettability, and the adhesion primer layer. There is a method of forming the adhesion auxiliary processing portions 5 and 6 by forming.
When the adhesion auxiliary treatment portion 5 is provided on the vapor deposition layer 3, it is preferable to form the adhesion auxiliary treatment portion 5 with an adhesion primer layer.
Examples of the treatment for physically modifying and improving the wettability include a corona treatment using corona discharge and a reactive etching treatment using plasma, and this treatment improves the roughness of the surface at the nano level. And the wettability is improved.

The adhesive primer layers constituting the adhesive auxiliary treatment portions 5 and 6 are provided to improve the adhesion with the wood-based base material of the decorative board, and specifically, the ester resin and the urethane resin. , Acrylic resin, Polycarbonate resin, Vinyl chloride-vinyl acetate copolymer, Polyvinyl butyral resin, Nitrocellulose resin, etc. These resins can be used alone or mixed to form an adhesive composition and roll coated. It can be formed by using an appropriate coating means such as a method or a gravure printing method.
The primer forming the adhesive primer layer is particularly preferably formed of a resin composed of a copolymer of an acrylic resin and a urethane resin and an isocyanate. That is, the copolymer of the acrylic resin and the urethane resin contains an acrylic polymer component (component A) having a hydroxyl group at the terminal, a polyester polyol component (component B) having a hydroxyl group at both ends, and a diisocyanate component (component C). It is obtained by reacting with each other to form a prepolymer, and further adding a chain extender (component D) such as diamine to the prepolymer to extend the chain. By this reaction, polyester urethane is formed and an acrylic polymer component is introduced into the molecule to form an acrylic-polyester urethane copolymer having a hydroxyl group at the terminal. It is formed by reacting the hydroxyl group at the end of this acrylic-polyester urethane copolymer with isocyanate and curing it.

As the component A, a linear acrylic acid ester polymer having a hydroxyl group at the terminal is used. Specifically, linear polymethylmethacrylate (PMMA) having a hydroxyl group at the terminal is preferable because it has excellent weather resistance (particularly, characteristics against photodegradation) and can be easily copolymerized with urethane for compatibility. .. Component A is an acrylic resin component in the copolymer, and those having a molecular weight of 5000 to 7000 (weight average molecular weight) are preferably used because they have particularly good weather resistance and adhesiveness. Further, as the component A, only those having hydroxyl groups at both ends may be used, but those having a conjugated double bond at one end may be mixed with the above-mentioned one having hydroxyl groups at both ends. It's a good one.

Component B reacts with diisocyanate to form polyester urethane, and constitutes a urethane resin component in the copolymer. As the component B, a polyester diol having hydroxyl groups at both ends is used. The polyester diol is derived from an addition reaction product of a diol compound having an aromatic or spirocyclic skeleton and a lactone compound or a derivative thereof, or an epoxy compound, a condensation product of a dibasic acid and a diol, and a cyclic ester compound. Induced polyester compounds and the like can be mentioned. Examples of the diol include short-chain diols such as ethylene glycol, propylene glycol, diethylene glycol, butanediol, hexanediol and methylpentenediol, and alicyclic short-chain diols such as 1,4-cyclohexanedimethanol. .. Examples of the basic acid include adipic acid, phthalic acid, isophthalic acid, and terephthalic acid. The polyester polyol is preferably adipic acid or a mixture of adipic acid and terephthalic acid as an acid component, particularly adipic acid, and an adipate system using 3-methylpentenediol and 1,4-cyclohexanedimethanol as diol components. It is polyester.

The urethane resin component formed by the reaction of the component B and the component C gives flexibility to the adhesive primer layer and contributes to the improvement of the adhesiveness. Further, the acrylic resin component composed of the acrylic polymer contributes to the weather resistance and blocking resistance of the adhesive primer layer. In the urethane resin, the molecular weight of the component B may be within the range in which a urethane resin capable of sufficiently exhibiting flexibility in the adhesive primer layer can be obtained, and adipic acid or a mixture of adipic acid and terephthalic acid and 3-. In the case of a polyester diol composed of methylpentanediol and 1,4-cyclohexanedimethanol, 500 to 5000 (weight average molecular weight) is preferable.

As the component C, an aliphatic or alicyclic diisocyanate compound having two isocyanate groups in one molecule is used. Examples of this diisocyanate include tetramethylene diisocyanate, 2,2,4 (2,4,4) -1,6-hexamethylene diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, and 1,4'-cyclohexyl. Diisocyanate and the like can be mentioned. As the diisocyanate component, isophorone diisocyanate is preferable because it has excellent physical properties and cost. The equivalent ratio of the isocyanate group to the total hydroxyl group (which may be an amino group) of the acrylic polymer, polyester polyol, and chain extender described later when reacting the components A to C is such that the isocyanate group becomes excessive. ..

When the three components A, B, and C are reacted at 60 to 120 ° C. for about 2 to 10 hours, the isocyanate group of the diisocyanate reacts with the hydroxyl group at the terminal of the polyester polyol to form the polyester urethane resin component and the terminal of the acrylic polymer. A compound in which diisocyanate is added to the hydroxyl group is also mixed, and a prepolymer in a state where an excess isocyanate group and the hydroxyl group remain is formed. As a chain extender, for example, diamines such as isophoronediamine and hexamethylenediamine are added to this prepolymer to react the isocyanate group with the chain extender, and the chain is extended to introduce the acrylic polymer component into the molecule of polyester urethane. The acrylic-polyester urethane copolymer of (I) having a hydroxyl group at the terminal can be obtained.

Well-known coating methods such as gravure coating method and roll coating method, in which isocyanate is added to the acrylic-polyester urethane copolymer and the coating solution is adjusted to the required viscosity in consideration of the coating method and the coating amount after drying. The adhesive primer layer may be formed by applying with. Further, the isocyanate may be any as long as it can be crosslinked and cured by reacting with the hydroxyl group of the acrylic-polyester urethane copolymer. Aliphatic isocyanate is desirable from the viewpoint of discoloration prevention and weather resistance. Specifically, a monomer of tolylene diisocyanate, xylylene diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, lysine diisocyanate, or a multimer such as a dimer or a trimer of these, or , Polyisocyanate such as a derivative (adduct body) in which these isocyanates are added to a polyol can be mentioned.
The coating amount after drying of the adhesive primer layer is 0.5 to 20 g / ^{m 2,} preferably from 1 to 5 g / ^{m 2.} Further, the adhesive primer layer may be a layer to which an additive such as a filler such as silica powder, a light stabilizer, or a colorant is added, if necessary.

Next, an example of a decorative board using the moisture-proof sheet 1 of the present embodiment will be described.
In the present embodiment, a case where the decorative board is applied to a door panel which is a fitting will be described as an example. Not limited to this. It may be applied to a decorative board such as a floor panel.
The adhesive used to attach the moisture-proof sheet 1 of the present embodiment to a decorative board or the like is, for example, any type of adhesive such as a thermoplastic resin type, a thermosetting resin type, and a rubber (elastomer) type. It may be. As these, known ones or commercially available products can be appropriately selected and used. Examples of the thermoplastic resin adhesive include polyvinyl acetate resin, polyvinyl alcohol, polyvinyl acetal (polyvinyl formal, polyvinyl butyral, etc.), cyanoacrylate, polyvinyl alkyl ether, polyvinyl chloride, polyamide, polymethyl methacrylate, and nitrocellulose. , Cellulose acetate, thermoplastic epoxy, polystyrene, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer and the like, and examples of the heat-curable resin-based adhesive include urea resin and melamine resin. , Phenolic resin, resorcinol resin, furan resin, epoxy resin, unsaturated polyester resin, polyurethane resin, polyimide resin, polyamideimide, polyvinyl imidazole, polybenzothiazole and the like. As rubber-based adhesives, natural rubber, recycled rubber, styrene-butadiene rubber, acrylonitrile-butadiene rubber, chloroprene rubber, butyl rubber, polysulfide rubber, silicone rubber, polyurethane rubber, stereo rubber (synthetic natural rubber), ethylene propylene rubber, block Copolymer rubber (SBS, SIS, SEBS, etc.) and the like can be mentioned.

The moisture-proof sheet of the present embodiment has a moisture-proof performance with a water vapor permeability of 3.0 g / m ² , day, atm or less because the base material layer is composed of a thermoplastic resin sheet, so that the temperature and humidity of the environment are met. It is possible to suppress the warp of the pasted decorative board against the influence of the change of.
Further, when the vapor deposition layer 3 is provided, the moisture-proof performance is further improved, and it is possible to achieve a water vapor permeability of, for example, 1.0 g / m ² , day, atm or less.
Further, by having the printing layer 4, it is possible to impart designability to the moisture-proof sheet.
For example, if the instruction sheet or drawing of the sheet construction procedure is configured as the print layer 4, the moisture-proof sheet 1 can be easily used.
When a pattern is formed by the print layer 4, when the decorative sheet is attached on the upper side, if the decorative sheet has transparency, it is possible to give a high-class feeling to the fitting provided with the moisture-proof sheet.
Further, by providing the adhesive auxiliary treatment portions 5 and 6 on both sides of the moisture-proof sheet, it becomes easy to withstand the influence of changes in temperature and humidity and maintain the adhesiveness of the moisture-proof sheet with the decorative plate and the like.
Here, it is preferable to provide a resin layer (not shown) between the printing layer 4 and the adhesion auxiliary processing unit 5.

As the resin layer, for example, polyvinyl alcohol or a composition obtained by adding an inorganic oxide typified by silicon oxide, magnesium oxide, or aluminum oxide to polyvinyl alcohol can be used, and this can be used by a roll coating method, a gravure coating method, or the like. It is possible to apply and form by the well-known coating method of.
When the adhesive auxiliary treatment portions 5 and 6 are composed of a primer layer, the primer layer is, for example, an ester resin, a urethane resin, an acrylic resin, a polycarbonate resin, a vinyl chloride-vinyl acetate copolymer, or a polyvinyl butyral type. Examples thereof include resins and nitrocellulose resins, and these resins can be used alone or mixed to form an adhesive composition, which can be formed by using an appropriate coating means such as a roll coating method or a gravure printing method.

Next, the present invention will be described in more detail with reference to Examples below.
<Example 1>
A PET film made of a biaxially stretched polyethylene terephthalate film having a thickness of 12 μm was used as the base material layer 2, a vapor-deposited layer 3 made of silicon oxide was formed on the surface of the base material layer 2, and a printing layer 4 was formed on the vapor-deposited layer 3.
Further, the back surface of the base material layer 2 is subjected to a corona discharge treatment (adhesion assisting treatment), and the corona discharge treatment surface and the surface on the printing layer 4 side are each cured into a urethane resin / salt vinegar resin as a main agent. A two-component curable resin to which isocyanate was added as an agent was formed by a gravure printing method to form an adhesive primer layer having a solid content of 1 g / m ² as an adhesive auxiliary treatment.
The moisture-proof sheet 1 is applied to a 3 mm-thick MDF with an ethylene-vinyl acetate copolymer adhesive at 8 g / m ² in a wet state, dried, and then rolled so that the vapor-deposited surface side of the moisture-proof sheet 1 is located on the coated surface. The decorative board of Example 1 attached with a laminating machine was produced.

<Comparative example 1>
23 g / m ² interstitial reinforced paper subjected to corona discharge treatment was placed on one surface so that the corona discharge treated surfaces faced each other, and PE was heated, melted and extruded to a thickness of 40 μm with a T-die extruder. A moisture-proof sheet 1 (inter-paper reinforcing paper 23 g / m ² / PE 40 μm / inter-paper reinforcing paper 23 g / m ² ) laminated by the so-called sandwich lamination method was produced.
The moisture-proof sheet 1 was coated with 8 g / m ^{2 of a} vinyl acetate-based adhesive on an MDF having a thickness of 3 mm in a wet state and dried, and then a decorative board was prepared by sticking it on the coated surface with a roll laminating machine.

<Evaluation>
The water vapor permeability, oxygen permeability, planar tensile strength, and transparency of the decorative boards of Example 1 and Comparative Examples 1 and 2 prepared above were evaluated. The results are summarized in Table 1.
-Water vapor permeability: The water vapor permeability is calculated by measuring the moisture-proof sheet 1 of Example 1 and Comparative Examples 1 and 2 in accordance with JIS Z 0208 "Moisture Permeability Test Method for Moisture-Proof Packaging Material (Cup Method)". did. The unit of water vapor permeability is g / m ² · day.
-Plane tensile strength: The planar tensile strength was calculated by measuring according to the JAS plywood planar tensile test. The unit of plane tensile strength is N / cm ² .
The decorative board used for the evaluation was a moisture-proof sheet 1 and MDF cold-pressed for 24 hours, the decorative board was cut into 5 cm squares, and a metal jig with a base of 2 cm square was placed on one surface of the moisture-proof sheet. After sticking with a system adhesive and curing at room temperature (about 23 ° C) for 24 hours, make a notch that reaches MDF along a metal jig with a cutter knife, and use a measuring test device to make a notch in the direction perpendicular to the test piece. The tension was evaluated by visually observing the peeling interface at that time, and the tensile strength was measured.

As is clear from Table 1, the moisture-proof sheet 1 of the present invention has a water vapor permeability of 3.0 g / m ² · day or less, so that the warp of the decorative board caused by changes in the temperature and humidity of the atmosphere can be prevented. It can be suppressed.
Further, in terms of the planar tensile strength, since the paper layer is not used for the layer structure, the delamination of the base material for the decorative board causes material destruction, and the peeling strength is improved as compared with the inter-paper peeling.

1 Moisture-proof sheet for building materials 2 Base material layer 3 Deposited layer 4 Printing layer 5, 6 Adhesive auxiliary processing unit

Claims (3)

It has a base material layer made of a thermoplastic resin film, a vapor deposition layer provided on one surface side of the base material layer, and a printing layer provided on the vapor deposition layer.
The water vapor permeability of the sheet is 3.0 g / m ² · day or less,
The thickness of the deposited layer state, and are within the scope of 5nm or 300nm or less,
Adhesion auxiliary processing parts are provided on both the front and back sides of the moisture-proof sheet.
The adhesive auxiliary processing unit is physically building materials moisture-proof sheet, wherein the wettability modifying region der Rukoto with improved wettability by reforming. It has a base material layer made of a thermoplastic resin film, a vapor deposition layer provided on one surface side of the base material layer, and a printing layer provided on the vapor deposition layer.
The water vapor permeability of the base material layer is 3.0 g / m ² · day or less.
Building materials moisture-proof sheet water vapor transmission rate of the sheet is equal to or less than 1.0g ^/ m 2 · day. The moisture-proof sheet for building materials according to claim 1 or 2, wherein the thickness of the vapor-deposited layer is in the range of 10 nm or more and 150 nm or less.

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