JP2024030972A - Moisture-proof decorative paper - Google Patents

Abstract

An object of the present invention is to provide a moisture-proof decorative paper that can reduce the amount of plastic material used and has excellent water vapor barrier properties even after the moisture-proof decorative paper is folded. A moisture-proof decorative paper 10 according to the present embodiment includes a moisture-proof layer a1 and a decorative layer a2 in this order on one surface of a paper base material 1, and the moisture-proof layer a1 is formed on one surface of a paper base material 1. An anchor coat layer 2, a metal oxide layer 4, and an overcoat layer 5 are provided in this order on one surface of the , and between the anchor coat layer 2 and the metal oxide layer 4, an acrylic resin, The decorative layer a2 has a resin layer 3 containing at least one resin selected from the group consisting of epoxy resin, acrylic urethane resin, polyester polyurethane resin, and polyether polyurethane resin, and the decorative layer a2 is on the moisture-proof layer a1. , a printed pattern layer 6, and a protective resin layer 7 in this order. [Selection diagram] Figure 1

Description

The present invention relates to a moisture-proof decorative paper used for fittings such as interior doors, kitchen doors, storage doors, sliding doors, etc. Specifically, the present invention has the function of preventing warping of decorative boards etc. caused by humidity changes, temperature changes, etc. , relates to a moisture-proof decorative paper whose moisture-proof properties do not decrease much even when folded.

Conventionally, fittings such as interior doors, kitchen doors, and storage doors have sometimes gradually warped during use due to humidity and temperature. This is a phenomenon that occurs mainly because the moisture content distribution inside the wooden fittings becomes uneven due to differences in humidity and temperature between indoors and outdoors. In other words, when a humidity difference occurs, there is a difference in the amount of moisture absorbed and released between the front and back surfaces of wooden fittings, and the higher humidity side expands due to the higher moisture content, while the lower humidity side causes contraction due to the lower moisture content. This causes warping. Furthermore, when a temperature difference occurs, the moisture contained in the wood base material moves to the colder side, creating a slope in the moisture content in the thickness direction, causing warping. Usually, the low temperature side often has high humidity and high water content, and in this case, the above two effects work in the same direction, so warping is considered to be most noticeable.

As a method of suppressing such warping of wooden fittings, a method is widely used in which a moisture-proof sheet with low moisture permeability is used as a member of the fitting to reduce the amount of moisture absorbed and released by the member. Furthermore, Patent Document 1 describes a moisture-proof structure having a five-layer structure on the surface side of a board base material such as plywood, which includes a protective resin layer, a printed pattern layer, paper reinforced paper, a synthetic resin layer, and paper reinforced paper. A decorative sheet is attached via an adhesive, and a moisture-proof back sheet having a three-layer structure of paper reinforced paper/synthetic resin/paper reinforced paper is attached to the back side of the board base material using an adhesive. It has been proposed that the moisture-proof decorative board be attached to the front and back of the flush door using an adhesive. At this time, the moisture permeability of the moisture-proof sheet is said to be preferably 5 (g/m ² ·24 h) or more and 30 (g/m ² ·24 h) or less.

In addition, depending on the purpose and design of these wooden fittings, decorative sheets may be bent and pasted along the corners of the surface of a three-dimensional base material, or decorative sheets may be attached to a flat base material. After being attached to a material, a V-shaped notch groove is cut and bent on the back surface of the base material to form a building material (V-cut processing), and the decorative sheet is sometimes used.

Patent No. 3206408

In recent years, from the viewpoint of door design, doors with a height of more than 2 meters are increasingly being adopted. As doors become taller, even a small amount of warpage causes the door as a whole to warp significantly, so sheets used for doors, etc. are required to have higher moisture resistance. A moisture-proof sheet having a synthetic resin base material, a metal vapor-deposited film, and a coating layer has been proposed as a sheet having high moisture-proof properties. The moisture permeability is less than 5 (g/m ² 24 h), and it is said to have a high warpage prevention effect.

However, since all of these moisture-proof sheets use plastic materials, it is desirable to reduce the amount of plastic used from an environmental standpoint. In addition, when recycling decorative boards, doors, and other fittings that are laminated with these moisture-proof sheets, it is necessary to separate the wood base material and plastic parts (synthetic resin layer and synthetic resin base material), making them suitable for recycling. In many cases, it is not.

In addition, from the perspective of effective resource utilization based on the Resource Effective Utilization Promotion Act, a proposal has been made to provide moisture resistance by providing a metal vapor-deposited film and a coating layer on the paper base material in order to reduce the amount of plastic materials used. has been done. In this case, it has been found that there is still room for improvement regarding the deterioration of moisture resistance (barrier properties) due to cracks and cracks in the metal vapor deposited film after bending.

The present invention was made to solve the above-mentioned problems in the conventional technology, and from the viewpoint of effective use of resources based on the Act on Promotion of Effective Utilization of Resources, the present invention is a moisture-proof decorative paper that can reduce the amount of plastic materials used. Therefore, not only the initial water vapor barrier property (that is, the water vapor barrier property before folding the moisture-proof decorative paper), but also the decrease in water vapor barrier property due to breakage or cracking of the metal vapor deposited film even when the moisture-proof decorative paper is folded. The purpose of the present invention is to provide a moisture-proof decorative paper that is less prone to moisture generation. In other words, an object of the present invention is to provide a moisture-proof decorative paper that can reduce the amount of plastic material used and has excellent water vapor barrier properties even after the moisture-proof decorative paper is folded. do.

In order to achieve the above object, one aspect of the present invention provides a moisture-proof decorative paper comprising a paper base material, a moisture-proof layer, and a decorative layer, wherein the moisture-proof layer is disposed on one side of the paper base material. , the decorative layer is provided in this order, and the moisture-proof layer is provided with an anchor coat layer, a metal oxide layer, and an overcoat layer in this order on one surface of the paper base material, Between the anchor coat layer and the metal oxide layer, at least one resin selected from the group consisting of acrylic resin, epoxy resin, acrylic urethane resin, polyester polyurethane resin, and polyether polyurethane resin is included. There is provided a moisture-proof decorative paper comprising a resin layer, the decorative layer comprising a printing layer and a protective resin layer in this order on the moisture-proof layer. That is, the moisture-proof decorative paper according to one aspect of the present invention is a moisture-proof decorative paper comprising a paper base material, a moisture-proof layer, and a decorative layer, wherein the moisture-proof layer and the decorative layer are provided on one surface of the paper base material. The moisture-proof layer includes an anchor coat layer, a resin layer, a metal oxide layer, and an overcoat layer in this order on one side of the paper base material. , the decorative layer includes a printed pattern layer and a protective resin layer in this order on the moisture-proof layer.

According to one aspect of the present invention, it is possible to reduce the amount of plastic material used, and it is possible to maintain excellent water vapor barrier properties even after the moisture-proof decorative paper is folded. Therefore, according to one aspect of the present invention, it is possible to further prevent the occurrence of warpage in decorative boards and the like while reducing the amount of plastic used.
More specifically, according to one aspect of the present invention, there is provided a moisture-proof decorative paper using paper, which has not only initial water vapor barrier properties (that is, water vapor barrier properties before folding the moisture-proof decorative paper) but also moisture-proof decorative paper. It is possible to provide a moisture-proof decorative paper that has sufficient water vapor barrier properties even after being folded. Since the moisture-proof decorative paper uses paper, it contributes to reducing the amount of plastic materials used.

1 is a schematic cross-sectional view showing an example of the structure of a moisture-proof decorative paper according to an embodiment of the present invention.

Embodiments of the present invention will be described below with reference to the drawings.
Here, the drawings are schematic, and the relationship between the thickness and the planar dimension, the ratio of each thickness, etc. are different from the actual one. In addition, the embodiments shown below illustrate configurations for embodying the technical idea of the present invention, and the technical idea of the present invention is based on the materials, shapes, etc. of the component parts as shown below. It is not specific. The technical idea of the present invention can be modified in various ways within the technical scope defined by the claims.

<Configuration>
FIG. 1 is a schematic cross-sectional view showing the structure of the moisture-proof decorative paper according to this embodiment. As shown in FIG. 1, the moisture-proof decorative paper 10 according to the present embodiment includes a paper base material 1, an anchor coat layer 2, a resin layer 3, a metal oxide layer 4, an overcoat layer 5, and a printed pattern. The layer 6 and the protective resin layer 7 are laminated in this order. The anchor coat layer 2, the resin layer 3, the metal oxide layer 4, and the overcoat layer 5 constitute the moisture-proof layer a1, and the printed pattern layer 6 and the protective resin layer 7 constitute the decorative layer a2. There is.

The resin layer 3 contains at least one resin selected from the group consisting of acrylic resin, epoxy resin, acrylic urethane resin, polyester polyurethane resin, and polyether polyurethane resin.

Next, the structure of each layer will be explained.
<Paper base material>
The paper base material 1 is not particularly limited, and may be appropriately selected depending on the application of the moisture-proof decorative paper 10 to which it is applied.
Specific examples of the paper base material 1 include tissue paper, wood-free paper, art paper, cast-coated paper, kraft paper, titanium paper, linter paper, paperboard, gypsum board paper, wood-free paper, coated paper, parchment paper, glassine paper, and parchment paper. , paraffin paper, Japanese paper, etc.
Preferably, thin paper (so-called interpaper reinforced paper) in which paper components (for example, cellulose fibers) are mixed with a synthetic resin to strengthen interpaper strength, or paper impregnated with latex or synthetic resin is used.

The basis weight of the paper base material 1 is not particularly limited, but if it is less than 20 g/ ^m2 , it will be too flexible and wrinkles will easily occur during processing, and if it is ^more than 200 g/m2, it will peel off from the paper layer (so-called , delamination) is likely to occur, so it is preferably within the range of 20 g/m ² or more and 200 g/m ² or less, more preferably within the range of 20 g/m ² or more and 100 g/m ² or less, and 20 g/m ² or more and 50 g/m 2 or less. It is more preferably within the range of m ² or less.

Furthermore, these paper base materials 1 may be subjected to surface treatments such as corona treatment, plasma treatment, flame treatment, etc., if necessary.

<Coat layer>
The paper base material 1 may be provided with a coat layer (not shown) at least on the side that is in contact with the anchor coat layer 2 described later. By providing the coat layer, it is possible to prevent the anchor coat layer 2 from seeping into the paper base material 1, and it can also serve as a filler to fill in the irregularities on the surface of the paper base material 1. Therefore, if the paper base material 1 has a coat layer on its surface, the anchor coat layer 2 can be uniformly formed without defects such as coating unevenness.

The coating layer contains binder resins such as various copolymers such as styrene/butadiene, styrene/acrylic, ethylene/vinyl acetate, polyvinyl alcohol resin, cellulose resin, paraffin (WAX), etc. Furthermore, fillers such as clay, kaolin, calcium carbonate, talc, and mica may be included.

The thickness of the coat layer is not particularly limited, but is preferably within the range of 1 μm or more and 10 μm or less, and more preferably within the range of 3 μm or more and 8 μm or less.

The mass of the paper base material 1 is preferably 50% by mass or more, more preferably 70% by mass or more, and even more preferably 80% by mass or more, based on the mass of the entire moisture-proof layer a1. If the mass of the paper base material 1 is 50% by mass or more based on the mass of the entire moisture-proof layer a1, a sheet made of synthetic resin such as vinyl chloride, polyethylene, polypropylene (plastic material 90% by mass or more) or paper/polyethylene/ Compared to conventional moisture-proof materials such as paper moisture-proof sheets (depending on the thickness of the polyethylene, to have moisture-proof performance, polyethylene must be at least 50% by mass), it uses less plastic. The proportion of plastic materials contained in moisture-proof decorative paper can be sufficiently reduced. In addition, since 50% by mass or more is paper material, the moisture-proof decorative paper 10 according to the present embodiment can be said to be made of paper (indicate that it is "made of paper"), and is recyclable. It is also excellent.

Note that the upper limit of the ratio of the mass of the paper base material 1 to the mass of the entire moisture-proof layer a1 is not particularly limited, but from the viewpoint of productivity, it may be 300% by mass or less, and even if it is 200% by mass or less. The content is preferably 150% by mass or less, more preferably 120% by mass or less, and even more preferably 120% by mass or less.

<Moisture-proof layer>
The moisture-proof layer a1 according to the present embodiment includes an anchor coat layer 2, a resin layer 3, a metal oxide layer 4, and an overcoat layer 5 in this order. The resin layer 3 is made of at least one resin selected from the group consisting of acrylic resin, epoxy resin, acrylic urethane resin, polyester polyurethane resin, and polyether polyurethane resin (hereinafter also referred to as "specific resin" for convenience). )including.

The moisture-proof layer a1 has the resin layer 3 containing the above-mentioned specific resin between the anchor coat layer 2 and the metal oxide layer 4, so that the moisture-proof layer a1 has initial water vapor barrier properties (that is, water vapor barrier properties before the moisture-proof decorative paper 10 is folded). It is possible to have not only sufficient water vapor barrier properties (barrier properties) but also sufficient water vapor barrier properties even after the moisture-proof decorative paper 10 is folded. In other words, by providing the resin layer 3 containing the above-mentioned specific resin between the anchor coat layer 2 and the metal oxide layer 4, the moisture-proof layer a1 can be used not only before the moisture-proof decorative paper 10 is folded, but also before the moisture-proof decorative paper 10 is folded. Even after the paper 10 is folded, it is possible to maintain sufficient water vapor barrier properties to withstand use.

The present inventors speculate as follows about the reason why the above effects are achieved. In the case of moisture-proof decorative paper that uses paper as the base material, polyolefin resin or polyvinyl alcohol resin is used between the paper base material and the barrier layer (barrier layer using a substance other than metal oxide as a constituent material). By providing the anchor coat layer, the moisture-proof decorative paper tends to maintain good water vapor barrier properties after being folded. However, if a barrier layer using a metal oxide is formed on the anchor coat layer, defects may easily occur in the metal oxide layer when the moisture-proof decorative paper is folded, and the water vapor barrier properties may become unstable. The inventors have discovered.

As a result of intensive studies to solve this problem, in this embodiment, by providing a resin layer 3 containing the above-mentioned specific resin between the anchor coat layer 2 and the metal oxide layer 4, It is possible to suppress the occurrence of defects in the metal oxide layer 4 when the moisture-proof decorative paper 10 is folded, and stable and good water vapor barrier properties can be obtained with no variation both in the initial stage (before folding) and after folding. The present inventors have found that. This is because when the metal oxide layer 4 is formed by vapor deposition or the like, a certain amount of heat is applied to the underlying layer (the anchor coat layer 2 in this embodiment), and the resin layer 3 containing the above-mentioned specific resin. This is thought to be because if it exists, it has excellent heat resistance and can suppress deformation of the base layer (anchor coat layer 2 in this embodiment) due to heat. As a result, cracks that may occur in the metal oxide layer 4 formed on the resin layer 3 at the initial stage (before bending) and after bending are suppressed, and it is considered that good water vapor barrier properties can be obtained.

That is, when the metal oxide layer 4 is formed directly on the anchor coat layer 2, the anchor coat layer 2 is deformed by heat, and it is considered that defects occur in the metal oxide layer 4 formed thereon. In addition, the resin layer 3 containing the above-mentioned specific resin has excellent adhesion to the anchor coat layer 2 and the metal oxide layer 4, and stabilizes good water vapor barrier properties both at the initial stage (before bending) and after bending. You can get it.

By using the above-mentioned moisture-proof layer A1, a moisture-proof layer with a high proportion of paper components, stable and excellent water vapor barrier properties, and less deterioration of the water vapor barrier properties after bending is used, which addresses the issue of plastic removal and marine debris. A decorative paper 10 can be provided.

<Anchor coat layer>
The anchor coat layer 2 is provided on the surface of the paper base material 1, and is provided to improve the adhesion between the paper base material 1 and the resin layer 3, which will be described later, and to improve the gas barrier properties of the moisture-proof decorative paper 10. It is something. The anchor coat layer 2 may contain at least one of a polyolefin and a polyvinyl alcohol resin having a polar group. Thereby, the moisture-proof decorative paper 10 has excellent gas barrier properties (particularly water vapor barrier properties).

More specifically, the anchor coat layer 2 may contain polyvinyl alcohol resin since it has excellent both water vapor barrier properties and oxygen barrier properties. Further, when the anchor coat layer 2 contains a polyolefin having a polar group, a dense film can be formed due to the crystallinity of the polyolefin, and water vapor barrier properties are exhibited. In other words, by including a polyolefin having a polar group in the anchor coat layer 2, excellent water vapor barrier properties are exhibited due to the crystallinity of the polyolefin, and adhesion with the resin layer 3 is achieved due to the polar group possessed by the polyolefin. is expressed.

The polyolefin having a polar group may have at least one selected from a carboxyl group, a salt of a carboxyl group, a carboxylic acid anhydride group, and a carboxylic acid ester.

In addition, as polyolefins with polar groups, ethylene or propylene is copolymerized with unsaturated carboxylic acids (unsaturated compounds with carboxyl groups such as acrylic acid, methacrylic acid, maleic anhydride) or unsaturated carboxylic acid esters. , and salts obtained by neutralizing carboxylic acid with a basic compound may also be used.
In addition, as the polyolefin having a polar group, polyolefins copolymerized with vinyl acetate, epoxy compounds, chlorine compounds, urethane compounds, polyamide compounds, etc. may also be used.

Specific examples of the polyolefin having a polar group include a copolymer of acrylic acid ester and maleic anhydride, an ethylene-vinyl acetate copolymer, an ethylene-glycidyl methacrylate copolymer, and the like.

The polyvinyl alcohol resin in this embodiment is, for example, a completely saponified polyvinyl alcohol resin, a partially saponified polyvinyl alcohol resin, a modified polyvinyl alcohol resin, or an ethylene-vinyl alcohol copolymer resin.

The degree of polymerization of the polyvinyl alcohol resin is preferably in the range of 300 or more and 1,700 or less, more preferably in the range of 500 or more and 1,200 or less, and even more preferably in the range of 700 or more and 1,000 or less. If the degree of polymerization is 300 or more, the gas barrier properties and bending resistance of the gas barrier laminate (moisture-proof layer a1) will be good, and if the degree of polymerization is 1700 or less, the viscosity of the coating liquid of polyvinyl alcohol resin described below will be low. This results in better coating properties.

When the anchor coat layer 2 contains a polyvinyl alcohol resin, in addition to the above-mentioned effect of being excellent in both water vapor barrier properties and oxygen barrier properties, it has excellent flexibility and gas barrier properties even after bending (folding). It is possible to suppress the deterioration of the anchor coat layer 2 and the resin layer 3, and also to improve the adhesion between the anchor coat layer 2 and the resin layer 3.

The anchor coat layer 2 may contain other components in addition to the polar group-containing polyolefin and polyvinyl alcohol resin. Other components include, for example, polyolefins other than the above-mentioned polyolefins having polar groups, polyacrylic, polyester, polyurethane, polycarbonate, polyurea, melamine, phenol, polyethyleneimine, polylactic acid, polyamide, polyimide, starch and its derivatives, and cellulose. Examples include resins such as derivatives, and additives such as silane coupling agents, organic titanates, glycerin, glycols, casein, and waxes.

The content of the polyolefin having a polar group in the anchor coat layer 2 may be, for example, 50% by mass or more, 70% by mass or more, 90% by mass or more, and 100% by mass. good.
Further, the total content of polyvinyl alcohol resin in the anchor coat layer 2 may be, for example, 50% by mass or more, 70% by mass or more, 90% by mass or more, and 100% by mass. It may be.

Further, the total content of the polyolefin and polyvinyl alcohol resin having polar groups in the anchor coat layer 2 may be, for example, 50% by mass or more, 70% by mass or more, or 90% by mass or more. It may be 100% by mass.

Furthermore, when both a polyolefin having a polar group and a polyvinyl alcohol resin are added to the anchor coat layer 2, the content of the polyolefin having a polar group may be greater than the content of the polyvinyl alcohol resin. If the content of the polyolefin having a polar group is greater than the content of the polyvinyl alcohol resin, excellent flexibility can be imparted to the anchor coat layer 2 while maintaining high water vapor barrier properties.

Furthermore, when both a polyolefin having a polar group and a polyvinyl alcohol resin are added to the anchor coat layer 2, the content of the polyvinyl alcohol resin may be greater than the content of the polyolefin having a polar group. . When the content of the polyvinyl alcohol resin is greater than the content of the polyolefin having a polar group, high water vapor barrier properties can be imparted to the anchor coat layer 2 while maintaining excellent flexibility.

The thickness of the anchor coat layer 2 may be, for example, 1 μm or more, or 2 μm or more. Further, the thickness of the anchor coat layer 2 may be, for example, 20 μm or less, 10 μm or less, or 5 μm or less. If the thickness of the anchor coat layer 2 is 1 μm or more, the unevenness of the paper base material 1 described above can be efficiently filled, and the resin layer 3 and metal oxide layer 4 described below can be uniformly laminated. . Moreover, if the thickness of the anchor coat layer 2 is 20 μm or less, each of the above layers can be uniformly laminated while keeping costs down.

The anchor coat layer 2 can be provided by applying a coating liquid containing the above-mentioned constituent materials of the anchor coat layer 2 and a solvent onto the paper base material 1 and drying it. Examples of solvents contained in the coating liquid include water, methyl alcohol, ethyl alcohol, isopropyl alcohol, n-propyl alcohol, n-butyl alcohol, n-pentyl alcohol, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, toluene, hexane, Examples include heptane, cyclohexane, acetone, methyl ethyl ketone, diethyl ether, dioxane, tetrahydrofuran, ethyl acetate, and butyl acetate. These solvents may be used alone or in combination of two or more. Among these, from the viewpoint of properties, methyl alcohol, ethyl alcohol, isopropyl alcohol, toluene, ethyl acetate, methyl ethyl ketone, and water are preferred. Also, from the environmental point of view, methyl alcohol, ethyl alcohol, isopropyl alcohol, and water are preferred.

<Resin layer>
The resin layer 3 is provided on the surface of the anchor coat layer 2 to prevent defects from occurring in the metal oxide layer 4 and to improve the adhesion between the anchor coat layer 2 and the metal oxide layer 4 described below. It is provided for such purposes.

The resin layer 3 contains at least one resin selected from the group consisting of acrylic resin, epoxy resin, acrylic urethane resin, polyester polyurethane resin, and polyether polyurethane resin. Among these, the resin layer 3 is made of acrylic urethane resin, epoxy resin, polyester polyurethane resin, from the viewpoint of stably obtaining better water vapor barrier properties both at the initial stage (before bending) and after bending. It is also preferable that at least one resin selected from the group consisting of polyether-based polyurethane resins is included.

The resin layer 3 may contain a resin other than the specific resin mentioned above, but from the viewpoint of stably obtaining better water vapor barrier properties both at the initial stage (before bending) and after bending, the resin The content of the specific resin in the layer 3 is preferably 50% by mass or more, more preferably 70% by mass or more, based on the total amount of the resin layer 3.
In addition, in this embodiment, the resin layer 3 may be formed only of the above-mentioned specific resin. That is, the content of the specific resin in the resin layer 3 may be 100% by mass based on the entire amount of the resin layer 3.

The resin layer 3 can be provided by applying a coating liquid containing the above-mentioned constituent materials of the resin layer 3 and a solvent onto the anchor coat layer 2 and drying the coating liquid. Examples of solvents contained in the coating liquid include esters such as ethyl acetate and butyl acetate; alcohols such as methanol, ethanol, and isopropyl alcohol; ketones such as methyl ethyl ketone; and aromatic hydrocarbons such as toluene and xylene. can be mentioned. Further, the resin layer 3 after drying may be subjected to an aging treatment within a temperature range of about 40° C. or higher and 60° C. or lower, if necessary.

Such a resin layer 3 has excellent heat resistance, can suppress cracking of the metal oxide layer 4 in the initial stage (before bending), and improves the adhesion between the metal oxide layer 4 and the resin layer 3. be able to. The resin layer 3 is preferably in contact with the metal oxide layer 4 from the viewpoint of obtaining the above effects more effectively. Moreover, it is preferable that the resin layer 3 is in contact with the anchor coat layer 2 from the viewpoint of obtaining the above effects more effectively.

The thickness of the resin layer 3 may be, for example, 0.01 μm or more, 0.05 μm or more, 0.1 μm or more, or 0.5 μm or more. Further, the thickness of the resin layer 3 may be, for example, 3 μm or less, 2 μm or less, or 1.5 μm or less. If the thickness of the resin layer 3 is 0.01 μm or more, cracking of the metal oxide layer 4 can be suppressed, and better water vapor barrier properties can be stably obtained at the initial stage (before bending) and after bending. Can be done. Moreover, if the thickness of the resin layer 3 is 3 μm or less, the metal oxide layer 4 can be uniformly laminated while keeping costs down.

<Metal oxide layer>
The metal oxide layer 4 is a layer containing metal oxide. The metal oxide layer 4 can be formed by vapor depositing a metal oxide. Examples of metal oxides include aluminum oxide (AlOx) and silicon oxide (SiOx).

The thickness of the metal oxide layer 4 may be appropriately set depending on the intended use, but is preferably 10 nm or more, more preferably 20 nm or more, and still more preferably 30 nm or more. Further, the thickness of the metal oxide layer 4 is preferably 100 nm or less, more preferably 80 nm or less. Setting the thickness of the metal oxide layer 4 to 10 nm or more facilitates ensuring sufficient continuity of the metal oxide layer 4, and setting the thickness to 100 nm or less prevents curls in the moisture-proof decorative paper 10 and cracks in the metal oxide layer 4. generation can be sufficiently suppressed, and sufficient gas barrier performance and flexibility can be easily achieved. Furthermore, by setting the thickness of the metal oxide layer 4 within the range of 10 nm or more and 100 nm or less, more preferably within the range of 20 nm or more and 40 nm or less, the metal oxide layer 4 becomes more difficult to break and bends. Sufficient water vapor barrier properties can be obtained even after the treatment.

The metal oxide layer 4 is preferably formed by vacuum film forming means from the viewpoint of water vapor barrier performance and film uniformity. Film forming methods include known methods such as vacuum evaporation, sputtering, and chemical vapor deposition (CVD), but vacuum evaporation is preferred because of its fast film formation rate and high productivity. Among vacuum evaporation methods, electron beam heating is particularly effective because the deposition rate can be easily controlled by adjusting the irradiation area, electron beam current, etc., and the temperature of the evaporation material can be raised and lowered in a short time. be.

<Overcoat layer>
Overcoat layer 5 is provided on the surface of metal oxide layer 4 so as to be in contact with metal oxide layer 4 . Overcoat layer 5 may contain polyolefin having a polar group.

The polyolefin having a polar group may have at least one selected from a carboxyl group, a salt of a carboxyl group, a carboxylic acid anhydride group, and a carboxylic acid ester.

In addition, polyolefins with polar groups include copolymerization of ethylene or propylene with unsaturated carboxylic acids (unsaturated compounds with carboxyl groups such as acrylic acid and methacrylic acid), unsaturated carboxylic acid esters, and carboxylic acid A salt obtained by neutralizing with a basic compound may also be used.
In addition, as the polyolefin having a polar group, those copolymerized with vinyl acetate, epoxy compounds, chlorine compounds, urethane compounds, polyamide compounds, etc. may also be used.

As the polyolefin having a polar group, specifically, a copolymer of acrylic acid ester and maleic anhydride, an ethylene-vinyl acetate copolymer, an ethylene-glycidyl methacrylate copolymer, etc. may be used.

By containing the polyolefin having a polar group, the overcoat layer 5 has excellent flexibility and can suppress cracks in the metal oxide layer 4 that occur after bending (folding). Excellent adhesion with. Furthermore, by including the above-described polyolefin having a polar group, a gas barrier laminate (moisture-proof layer a1) having excellent water vapor barrier properties can be obtained.

The overcoat layer 5 may contain other components in addition to the above-mentioned polyolefin having a polar group. Examples of other components include silane coupling agents, organic titanates, polyacrylics, polyesters, polyurethanes, polycarbonates, polyureas, polyamides, polyolefin emulsions, polyimides, melamine, and phenols.

The content of the polyolefin having a polar group in the overcoat layer 5 may be, for example, 50% by mass or more, 70% by mass or more, 90% by mass or more based on the mass of the entire overcoat layer 5. It may be 100% by mass.

The thickness of the overcoat layer 5 may be, for example, 2 μm or more, or 3 μm or more. Further, the thickness of the overcoat layer 5 may be 10 μm or less, 8 μm or less, or 5 μm or less. If the thickness of the overcoat layer 5 is 2 μm or more, it can fully exhibit its role as a protective layer for the metal oxide layer 4 described above. Further, if the thickness of the overcoat layer 5 is 10 μm or less, it is possible to sufficiently exhibit adhesiveness and barrier properties with the metal oxide layer 4 while suppressing costs.

The overcoat layer 5 can be provided by applying a coating liquid containing the above-mentioned polyolefin and a solvent onto the metal oxide layer 4 and drying it. Examples of solvents contained in the coating liquid include water, methyl alcohol, ethyl alcohol, isopropyl alcohol, n-propyl alcohol, n-butyl alcohol, n-pentyl alcohol, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, toluene, hexane, Examples include heptane, cyclohexane, acetone, methyl ethyl ketone, diethyl ether, dioxane, tetrahydrofuran, ethyl acetate, and butyl acetate. These solvents may be used alone or in combination of two or more. Among these, from the viewpoint of properties, methyl alcohol, ethyl alcohol, isopropyl alcohol, toluene, ethyl acetate, methyl ethyl ketone, and water are preferred. Also, from the environmental point of view, methyl alcohol, ethyl alcohol, isopropyl alcohol, and water are preferred.

The polyolefins having polar groups contained in the anchor coat layer 2 and the overcoat layer 5 may be of the same kind or different kinds, but in consideration of ease of production, etc. Preferably.

Although one embodiment of the moisture-proof layer a1 according to the present embodiment has been described above, the present invention is not limited thereto. The moisture-proof layer a1 may be a moisture-proof layer containing layers other than the layers described above.

<Print pattern layer>
The printed pattern layer 6 is for providing design, and any pattern can be used as the pattern. As the pattern of the printed pattern layer 6, for example, a wood grain pattern, a stone grain pattern, a cloth grain pattern, a cork pattern, an abstract pattern, or a combination of two or more of these can be used.
A solid ink layer can be provided between the printed pattern layer 6 and the overcoat layer 5 in order to ensure concealment properties. These printing methods are not particularly limited, and known printing methods such as gravure printing, offset printing, silk screen printing, and inkjet printing can be used.

There are no particular restrictions on the printing ink, and there are no particular problems with either oil-based or water-based inks. The printing ink used for the printed pattern layer 6 can be the same as the printing ink used for the printed pattern layer in conventional decorative paper, and for example, acrylic ink can be used. As the acrylic ink, for example, a two-component curable urethane resin ink made by blending an isocyanate curing agent into an acrylic polyol vehicle can be used.

<Protective resin layer>
The protective resin layer 7, which functions as a surface protection layer, is a layer for protecting the surface of the moisture-proof decorative paper 10, and has the properties required for the moisture-proof decorative paper 10, such as scratch resistance, abrasion resistance, stain resistance, water resistance, It is provided to impart surface properties such as weather resistance. The formation of the protective resin layer (surface protective layer) 7 is not particularly limited, and can be formed by a known coating method such as gravure coating.

The material for the protective resin layer (surface protective layer) 7 is not particularly limited, and materials similar to those used as the surface protective layer in conventional decorative papers can be used. Examples of materials that can be used for the protective resin layer (surface protective layer) 7 include acrylic urethane resins and ionizing radiation-curable resins. As the acrylic urethane resin, for example, a reaction product containing an acrylic polyol compound as a main ingredient and an isocyanate compound as a curing agent can be employed. In addition, examples of ionizing radiation-curable resins include prepolymers, oligomers, and monomers having polymerizable unsaturated bonds such as (meth)acryloyl groups that have the property of crosslinking upon irradiation with ionizing radiation such as electron beams and ultraviolet rays. A composition containing at least one of them as a main component can be employed.

The protective resin layer (surface protective layer) 7 may be a single layer or a multilayer of two or three layers. When the protective resin layer 7 is made into a multi-layer, a gloss matte expression can also be given by separately applying matte resin and gloss resin. Moreover, it is also possible to give an uneven expression by partially raising the resin. Furthermore, antibacterial agents, antiviral agents, etc. can also be added.

<Applications of moisture-proof decorative paper>
As described above, the moisture-proof decorative paper 10 of this embodiment is suitable for application to building materials such as door frame materials, furniture doors, door surface materials, wall surfaces, flooring materials, etc., and is particularly suitable for use in flush panels including V-cut processing. Most suitable for surface materials such as (flush doors).

A flash panel has a hollow flat plate member made by gluing plate materials such as plywood or medium density fiberboard (MDF) to the front and back sides of a core material made of frame materials such as square timber assembled vertically and horizontally, and has a large area. It has the advantage of being lightweight and able to be manufactured with sufficient strength by using a small amount of inexpensive material for a thick flat plate member, and is widely used for interior doors, furniture doors, etc. There is.

In such a flush panel, if both sides of the panel are exposed to environments with significantly different temperature and humidity, or if placed in an environment with rapid changes in temperature and humidity, the moisture content inside the panels on the front and back sides of the core material will become uniform. As a result, the flash panel as a whole may warp as a result of the change in dimensions.
To prevent this, moisture-proof sheets (moisture-proof paper) are often attached to the front and back surfaces of the front and back plates of the core material.

In many cases, the front and back plates of the core material are subjected to a bending process, such as a V-cut, for the purpose of forming side parts or frame parts of the panel. The moisture-proof decorative paper 10 of this embodiment not only has sufficient moisture-proofing properties, but also maintains sufficient moisture-proofing properties with almost no reduction in water vapor barrier properties even during bending. In such applications, it is suitable for use by being attached to the surfaces of the front and back plates of the flash panel (the surface opposite to the core material side).

Note that the moisture-proof sheet (moisture-proof paper) attached to the back surface (the surface on the core material side) of the front and back plates of the flash panel is the moisture-proof sheet provided with the moisture-proof layer a1 of this embodiment (i.e., the moisture-proof makeup of this embodiment). Of course, paper 10) may also be used, but since V-cut processing is usually not applied from the front side (the moisture-proof sheet on the back side is rarely used folded), the moisture-proof sheet of this embodiment A normal moisture-proof sheet (moisture-proof paper) may be used instead of the decorative paper 10.

Specifically, the moisture-proof sheet (moisture-proof paper) to be attached to the back side (the surface on the core material side) of the front and back plates of the flash panel can be, for example, a moisture-proof sheet made of paper/polyethylene/paper, or a synthetic resin film coated with metal vapor. A moisture-proof film with a protective layer can be used.

<Effect>
The moisture-proof decorative paper 10 of this embodiment can have lower moisture permeability (JIS Z 0208) than a sheet made of synthetic resin such as vinyl chloride, polyethylene, or polypropylene, or a moisture-proof sheet made of paper/polyethylene/paper. . Therefore, it is possible to obtain a moisture-proof decorative paper having excellent moisture-proofing performance, and also to provide a moisture-proof decorative paper whose water vapor barrier performance does not easily deteriorate even after bending.

In addition, in the moisture-proof decorative paper 10, since the mass of the paper base material 1 is 50% by mass or more based on the mass of the entire moisture-proof layer a1, a sheet made of synthetic resin such as vinyl chloride, polyethylene, polypropylene (plastic material 90% by mass) % or more) or moisture-proof sheets made of paper/polyethylene/paper (plastic materials of 50% or more), etc., the mass (content) of plastic used is small compared to conventional moisture-proof materials such as paper/polyethylene/paper moisture-proof sheets (plastic material 50% or more), so it can be used as a moisture-proof decorative paper. The amount of plastic material used can be significantly reduced.
In addition, fittings such as decorative boards and doors using this moisture-proof decorative paper 10 have high moisture-proof performance and are also excellent in recyclability because they are composed of wood materials and paper components.

[Example]
EXAMPLES The present invention will be explained in more detail with reference to Examples below, but the present invention is not limited to the following Examples.

<Production of moisture-proof decorative paper>
(Example 1)
As paper base material ¹ , a polyvinyl alcohol resin with a degree of saponification of 98 mol% and a degree of polymerization of 500 was applied to the surface of reinforced paper (manufactured by Tenma Tokushu Paper Co., Ltd.) with a basis weight of 50 g/m 2 in water/IPA=8/2. A coating liquid dissolved in a solvent of (mass ratio) was applied using a bar coater and dried in an oven to form an anchor coat layer 2 having a thickness of 3 μm.
Subsequently, a mixed solution of acrylic polyol and polyisocyanate is applied onto the anchor coat layer 2 so that the thickness after drying is 1 μm, and the resin layer 3 made of acrylic urethane resin is formed by heating and drying. Formed.

Thereafter, SiOx was deposited on the resin layer 3 by a vacuum evaporation method to form a metal oxide layer 4 with a thickness of 30 nm.
Thereafter, an aqueous dispersion of a polyolefin containing a salt of a carboxyl group, which is a polar group-containing polyolefin, is coated on the metal oxide layer 4 using a bar coater and dried in an oven to form an overcoat layer 5 with a thickness of 3 μm. did.
In this way, the moisture-proof layer a1 according to Example 1 was obtained.

(Example 2)
Anchor coat layer 2 was formed by the same operation as in Example 1, except that an aqueous dispersion of a polyolefin containing a salt of a carboxyl group, which is a polar group-containing polyolefin, was applied with a bar coater and dried in an oven. A moisture-proof layer a1 according to Example 2 was obtained.

(Example 3)
A moisture-proof layer a1 according to Example 3 was obtained in the same manner as in Example 1 except that the thickness of the metal oxide layer 4 was 10 nm.

(Example 4)
A moisture-proof layer a1 according to Example 4 was obtained by the same operation as in Example 1 except that the thickness of the metal oxide layer 4 was 100 nm.

(Example 5)
A moisture-proof layer a1 according to Example 5 was obtained by the same operation as in Example 1 except that the thickness of the resin layer 3 was 0.01 μm.

(Example 6)
A moisture-proof layer a1 according to Example 6 was obtained in the same manner as in Example 1 except that the thickness of the resin layer 3 was 3 μm.

(Example 7)
A moisture-proof layer a1 according to Example 7 was obtained in the same manner as in Example 1 except that the thickness of the anchor coat layer 2 was 1 μm.

(Example 8)
A moisture-proof layer a1 according to Example 8 was obtained in the same manner as in Example 1 except that the thickness of the anchor coat layer 2 was 5 μm.

(Example 9)
A moisture-proof layer a1 according to Example 9 was obtained in the same manner as in Example 1 except that the thickness of the overcoat layer 5 was 2 μm.

(Example 10)
A moisture-proof layer a1 according to Example 10 was obtained in the same manner as in Example 1 except that the thickness of the overcoat layer 5 was 10 μm.

(Example 11)
A moisture-proof layer a1 according to Example 11 was obtained by the same operation as in Example 1 except that the material of the metal oxide layer 4 was AlOx.

(Comparative example 1)
A moisture-proof layer a1 according to Comparative Example 1 was obtained in the same manner as in Example 1, except that the metal oxide layer 4 was vapor-deposited on the anchor coat layer 2 without forming the resin layer 3.

(Comparative example 2)
A moisture-proof layer a1 according to Comparative Example 2 was obtained in the same manner as in Example 2, except that the metal oxide layer 4 was deposited on the anchor coat layer 2 without forming the resin layer 3.

(Comparative example 3)
A moisture-proof layer a1 according to Comparative Example 3 was obtained in the same manner as in Example 1, except that the resin layer 3 was formed on the surface of the paper base material 1 without forming the anchor coat layer 2.

(Comparative example 4)
The anchor coat layer 2 was formed using the material, thickness, and formation method of the resin layer 3 of Example 1, and the resin layer 3 was formed using the material, thickness, and formation method of the anchor coat layer 2 of Example 1. Except for this, a moisture-proof layer a1 according to Comparative Example 4 was obtained by the same operation as in Example 1.

(Comparative example 5)
The anchor coat layer 2 was formed using the material, thickness, and formation method of the resin layer 3 of Example 2, and the resin layer 3 was formed using the material, thickness, and formation method of the anchor coat layer 2 of Example 2. Except for this, a moisture-proof layer a1 according to Comparative Example 5 was obtained by the same operation as in Example 2.

(Comparative example 6)
A moisture-proof layer a1 according to Comparative Example 6 was obtained in the same manner as in Example 1, except that the resin layer 3 was formed using the material, thickness, and formation method of the anchor coat layer in Example 2.

Next, the upper surface of the moisture-proof layer a1 laminated on the paper base material 1 of each of Examples 1 to 11 and Comparative Examples 1 to 6 was printed by gravure printing using ink containing nitrified cotton and acrylic resin as a binder. A solid ink layer was formed.
A pattern ink layer (print pattern layer 6) was formed thereon by gravure printing using an ink containing nitrified cotton and acrylic resin as a binder.

Subsequently, a surface protective layer (protective resin layer) 7 was formed by gravure printing using urethane-based acrylic polyol and isocyanate, and Examples 1 to 11 and comparative examples were provided with a moisture-proof layer a1 and a decorative layer a2. Each moisture-proof decorative paper 10 of Nos. 1 to 6 was obtained.

<Evaluation>
The water vapor permeability of each of the moisture-proof decorative papers 10 of Examples 1 to 11 and Comparative Examples 1 to 6 produced above was measured in accordance with JIS Z 0208, and the water vapor permeability (water vapor permeability before bending) of each was measured in accordance with JIS Z 0208. I made a comparison.

Further, while rolling a 600 g roller at a speed of 300 mm/min, creases were created in the gas barrier laminate (i.e., the moisture-proof decorative paper 10), and then the gas barrier laminate (i.e., in the state returned to the flat plate shape) ( That is, the water vapor permeability of the moisture-proof decorative paper 10) was also measured in the same manner.
Incidentally, the fold was a mountain fold on the side where the printed pattern layer 6 was located.
The results are shown in Tables 1 to 5.

As shown in Tables 1 to 5, the moisture-proof decorative papers 10 of Examples 1 to 11 had low water vapor permeability not only at the initial stage (before folding) but also after folding, and had good water vapor barrier properties.
In addition, in this example, if the water vapor permeability is 10 g/m ² · 24 h or less both before folding the moisture-proof decorative paper 10 and after folding the moisture-proof decorative paper 10, there is no problem in using it. It was evaluated as "passed". On the other hand, if the moisture vapor permeability of either the moisture-proof decorative paper 10 before folding or the moisture-proof decorative paper 10 after folding exceeds 10 g/m ² 24 h, there is a risk of problems in use. Therefore, it was rated as "fail".

As described above, the moisture-proof decorative paper according to the embodiment of the present invention maintains water vapor barrier properties for a long period of time even when the moisture-proof decorative paper is bonded to a wooden member having a bent portion to form a decorative board. It can be expected to have the effect of suppressing the deterioration of plastic materials and reducing the amount of plastic materials used.

Further, for example, the present invention can take the following configuration.
(1)
A moisture-proof decorative paper comprising a paper base material, a moisture-proof layer, and a decorative layer,
The moisture-proof layer and the decorative layer are provided in this order on one surface of the paper base material,
The moisture-proof layer includes an anchor coat layer, a metal oxide layer, and an overcoat layer in this order on one side of the paper base material,
Between the anchor coat layer and the metal oxide layer, at least one resin selected from the group consisting of acrylic resin, epoxy resin, acrylic urethane resin, polyester polyurethane resin, and polyether polyurethane resin is provided. Equipped with a resin layer containing
The moisture-proof decorative paper is characterized in that the decorative layer includes a printing layer and a protective resin layer in this order on the moisture-proof layer.

(2)
The moisture-proof decorative paper according to (1) above, wherein the anchor coat layer contains a polyolefin having a polar group.

(3)
The moisture-proof decorative paper according to (1) or (2) above, wherein the anchor coat layer contains a polyvinyl alcohol resin.

(4)
The moisture-proof decorative paper according to any one of (1) to (3) above, wherein the overcoat layer contains a polyolefin having a polar group.

(5)
The moisture-proof decorative paper according to any one of (1) to (4) above, wherein the metal oxide layer has a thickness of 10 nm or more and 100 nm or less.

(6)
The moisture-proof decorative paper according to any one of (1) to (5) above, wherein the resin layer has a thickness of 0.01 μm or more and 3 μm or less.

(7)
The moisture-proof decorative paper according to any one of (1) to (6) above, wherein the anchor coat layer has a thickness of 1 μm or more and 5 μm or less.

(8)
The moisture-proof decorative paper according to any one of (1) to (7) above, wherein the overcoat layer has a thickness of 2 μm or more and 10 μm or less.

(9)
The moisture-proof decorative paper according to any one of (1) to (8) above, wherein the paper base has a mass of 50% by mass or more based on the mass of the entire moisture-proof layer.

(10)
The moisture-proof decorative paper according to any one of (1) to (9) above, characterized in that the paper base material is paper reinforced paper.

1...Paper base material 2...Anchor coat layer 3...Resin layer 4...Metal oxide layer 5...Overcoat layer 6...Print pattern layer (printing layer)
7...Protective resin layer (surface protective layer)
10... Moisture-proof decorative paper a1... Moisture-proof layer a2... Decorative layer

Claims (10)

A moisture-proof layer and a decorative layer are provided in this order on one side of the paper base material,
The moisture-proof layer includes an anchor coat layer, a metal oxide layer, and an overcoat layer in this order on one side of the paper base material,
Between the anchor coat layer and the metal oxide layer, at least one resin selected from the group consisting of acrylic resin, epoxy resin, acrylic urethane resin, polyester polyurethane resin, and polyether polyurethane resin is provided. Equipped with a resin layer containing
The moisture-proof decorative paper is characterized in that the decorative layer includes a printing layer and a protective resin layer in this order on the moisture-proof layer. The moisture-proof decorative paper according to claim 1, wherein the anchor coat layer contains a polyolefin having a polar group. The moisture-proof decorative paper according to claim 1, wherein the anchor coat layer contains a polyvinyl alcohol resin. The moisture-proof decorative paper according to claim 2 or 3, wherein the overcoat layer contains a polyolefin having a polar group. The moisture-proof decorative paper according to claim 4, wherein the thickness of the metal oxide layer is within a range of 10 nm or more and 100 nm or less. The moisture-proof decorative paper according to claim 5, wherein the thickness of the resin layer is within a range of 0.01 μm or more and 3 μm or less. The moisture-proof decorative paper according to claim 6, wherein the thickness of the anchor coat layer is within a range of 1 μm or more and 5 μm or less. The moisture-proof decorative paper according to claim 7, wherein the thickness of the overcoat layer is within a range of 2 μm or more and 10 μm or less. The moisture-proof decorative paper according to claim 8, wherein the mass of the paper base material is 50% by mass or more based on the mass of the entire moisture-proof layer. The moisture-proof decorative paper according to claim 9, wherein the paper base material is paper reinforced paper.

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