WO2020026989A1 - Cosmetic sheet - Google Patents

Abstract

The present invention provides a cosmetic sheet having reworkability. This cosmetic sheet 1 is provided with: a surface layer 12 forming the outermost surface and including a layer made of at least a polyester resin; and an adhesive layer 13 laminated on the back surface side of the surface layer 12 and having multiple recesses on both surfaces thereof. The surface layer 12 is provided with a surface protection layer 122 formed on the front surface side of the polyester resin layer 121 made of the polyester resin. The adhesive layer 13 is formed by curing a liquid resin composition containing air bubbles, and multiple recesses 13a corresponding to the air bubbles are formed on both surfaces.

Description

Decorative sheet

The present invention relates to a decorative sheet.

2. Description of the Related Art A decorative sheet has been known in which a plastic sheet is used as a base material, a color, a pattern, and the like are applied to the base material, and a mirror surface is imparted to the surface.
These decorative sheets are used by being attached to various materials such as interior and exterior of buildings, building materials, furniture, and home electric appliances. By the specularity of the surface, it is possible to impart a design property for producing a feeling of cleanliness, luxury, and the like.
As a decorative sheet having such a mirror surface, a decorative sheet using a polyester film has been proposed (for example, Patent Document 1).

When attaching a decorative sheet to a material, apply an adhesive (also called an adhesive) to the decorative sheet side, the material side, or the surface on both sides during the pasting process, and attach the decorative sheet to the material Or by using an adhesive layer previously formed on the back surface of the decorative sheet.
In addition, if it is assumed that the decorative sheet that has been pasted is peeled off and the position to be pasted is changed and adjusted, and then it is pasted again, or if it is assumed that another decorative sheet will be pasted again on the trace where it was peeled off, It is also possible to use an adhesive which is relatively easy to peel (also called an adhesive) instead of the material. However, in reality, it is difficult to reuse a decorative sheet in the form of lamination using a conventional adhesive material, such as re-peeling and re-attaching. If the attachment fails, the peeled decorative sheet must be discarded because it is deformed or torn, and when reattaching to a material, it is necessary to clean the adhesive remaining on the surface of the material. For this reason, sticking a decorative sheet requires special equipment and requires a skilled craftsman, which is very difficult. In particular, in recent years, there has been a shortage of craftsmen, and inexperienced people and amateurs have frequently suffered damage in applying the decorative sheet.
Therefore, in order to make it easier to use the decorative sheet, it has been desired to enhance the so-called reworkability, in which the paste can be peeled off and pasted again when pasting fails or when the pasting is changed.

On the other hand, Patent Document 2 discloses a technique relating to a micro suction cup film including an adhesive layer having a large number of fine suction cup groups on an adherend surface. Since the micro suction cup film of Patent Document 2 can be reversibly attached to and detached from an adherend, if a decorative sheet provided with an adhesive layer composed of the micro suction cup film can be realized, a makeup having reworkability can be realized. It is considered possible to make a sheet. However, although the composition disclosed in Patent Document 2 is capable of producing a micro suction cup film even at a temperature of about room temperature, it realizes a sufficient balance between the adsorbing force and the peeling force with respect to the adherend and has a sufficient balance. It was difficult to stably produce a pressure-sensitive adhesive layer having reworkability, and the above composition could not be applied to a decorative sheet and used.

JP 2007-204966 A JP-A-2017-36404

課題 An object of the present invention is to provide a decorative sheet having reworkability.

The present invention solves the above problems by the following means. In addition, in order to make it easy to understand, description is given with reference numerals corresponding to the embodiment of the present invention, but the present invention is not limited to this.

According to a first aspect of the present invention, a surface layer (12) formed on the outermost surface and including at least a layer formed of a polyester-based resin is laminated on the back surface side of the surface layer (12), and a plurality of concave shapes ( 13a), and the concave shape (13a) is evenly formed on both surfaces of the adhesive layer (13), and is open to the surface on the surface layer (12) side. the average value of the diameter of each opening of the mean value of the diameters of the openings and D ave 1, wherein the surface layer (12) the opening on the opposite side of the concave (13a) of the concave (13a) when the D ave 2, | a / D ave 2 ≦ 0.5 decorative sheet satisfying the relationship (1,1B, 1C) | D ave 1 -D ave 2.

A second invention is characterized in that in the decorative sheet (1, 1B, 1C) according to the first invention, a layer thickness t of the adhesive layer (13) is in a range of 20 μm ≦ t ≦ 40 μm. Decorative sheets (1, 1B, 1C).

According to a third invention, in the decorative sheet (1C) according to the first invention or the second invention, the surface layer (12) is constituted only by a layer formed of a polyester resin. Characteristic decorative sheet (1C).

According to a fourth aspect of the present invention, in the decorative sheet (1, 1B) according to the first or second aspect, the surface layer (12) includes a layer (121) formed of a polyester-based resin and the polyester (121). A decorative sheet (1, 1B, 1C), comprising: a surface protective layer (122) formed on the surface side of a layer (121) formed of a base resin.

According to a fifth aspect, in the decorative sheet (1) according to any one of the first to fourth aspects, the decorative sheet (1) is disposed between the surface layer (12) and the adhesive layer (13), A decorative sheet (1) further comprising a decorative layer (11) including a pattern.

According to a sixth invention, in the decorative sheet (1, 1B, 1C) according to any one of the first invention to the fifth invention, the outermost surface of the surface layer (12) has a mirror surface. And a decorative sheet (1, 1B, 1C).

According to a seventh invention, in the decorative sheet (1, 1B, 1C) according to any one of the first invention to the sixth invention, the adhesive layer (13) is a liquid resin composition containing bubbles. The decorative sheet (1, 1B, 1C) is characterized in that a plurality of the concave shapes (13a) based on the bubbles are formed on both sides.

An eighth invention is the decorative sheet (1, 1B, 1C) according to any one of the first invention to the seventh invention, wherein the pressure-sensitive adhesive layer (13) has a density of 0.1 g / cm ³ or more. , 0.7 g / cm ³ or less.

According to a ninth invention, in the decorative sheet (1, 1B, 1C) according to any one of the first invention to the eighth invention, a peelable substrate sheet is provided on a back surface side of the adhesive layer (13). (15) is a laminated decorative sheet (1, 1B, 1C).

A tenth invention is characterized in that the decorative sheet (1, 1B, 1C) according to any one of the first invention to the ninth invention is configured to be wound in a roll. It is a decorative sheet (1, 1B, 1C).

According to the present invention, it is possible to provide a decorative sheet having reworkability.

It is a sectional view showing a 1st embodiment of a decorative sheet by the present invention. It is sectional drawing which shows the form at the time of use of the decorative sheet 1 in detail sequentially. It is a perspective view which shows the form which wound the decorative sheet 1 in the form of the roll 1R. It is a figure which shows the manufacturing apparatus of the decorative sheet 1. It is a figure explaining the manufacturing method of decorative sheet 1. It is the photograph which expanded the adhesion layer 13 of the decorative sheet 1 of the example when it looked at from the direction of the back surface side (adhesion side). It is the figure which expanded the cross section of the direction orthogonal to a sheet | seat surface about the back surface side (adhesive surface side) vicinity part of the adhesive layer 13 of the decorative sheet 1 of an Example. It is a figure which shows the peeling force of an Example and a comparative example. FIG. 9 is a diagram showing observation results of Sample 1. FIG. 9 is a diagram showing observation results of Sample 2. FIG. 9 is a diagram showing observation results of Sample 3. FIG. 9 is a diagram showing observation results of Sample 4. It is sectional drawing which shows 2nd Embodiment of a decorative sheet. It is sectional drawing which shows 3rd Embodiment of a decorative sheet.

Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings and the like.

(1st Embodiment)
FIG. 1 is a sectional view showing a first embodiment of a decorative sheet according to the present invention.
In addition, each figure shown below is a figure which showed typically except FIG. 6, FIG. 7, and FIG. 9-FIG. 13 of an actual photograph, and the magnitude | size and shape of each part are in order to make an understanding easy. Are exaggerated as appropriate.
In the following description, specific numerical values, shapes, materials, and the like will be described, but these can be changed as appropriate.
In the present specification, the terms such as plate, sheet, and film are used, but these are generally used in the order of thickness, plate, sheet, and film in the order of thickness. I use it even in the book. However, in the present invention, such use does not have a technical meaning, and therefore these terms can be appropriately replaced and used. Can be interpreted similarly.
Further, in the use state of the decorative sheet, the side that is the front side (the layer 121 formed of the polyester-based resin and is the upper side in FIG. 1) is referred to as the front side, and the opposite side (the adhesive layer 13 side, The lower side in FIG. 1 is referred to as a back side.

In the following description, first, as an example of a decorative sheet, as shown in FIG. 1, a decorative sheet 11 in which a decorative layer 11 and a surface layer 12 including a layer 121 formed of a polyester-based resin are laminated and bonded. This will be described. Hereinafter, “the layer 121 formed of a polyester-based resin” is also abbreviated as “polyester-based resin layer 121” for simplification. As will be described later, for example, a decorative sheet having only the polyester-based resin layer 121 without the decoration layer 11 may be used, or a configuration in which the polyester-based resin layer 121 does not include the surface protection layer 122 may be employed. .

In the embodiment illustrated in FIG. 1, the decorative sheet 1 includes a decorative layer 11, a surface layer 12, an adhesive layer 13, an adhesive layer 14, and a peelable base sheet 15.

(Decoration layer 11)
The decoration layer 11 includes a base layer 111 and a printing layer 112.
(Base material layer 111)
The base layer 111 is a base layer made of a thermoplastic resin. As the thermoplastic resin forming the base layer, low-density polyethylene (including linear low-density polyethylene), medium-density polyethylene (PP), high-density polyethylene, ethylene-α-olefin copolymer, polypropylene, polymethylpentene, Polyolefins such as polybutene, ethylene-propylene copolymer, propylene-butene copolymer, olefin-based thermoplastic elastomer, ionomer, or a mixture thereof; polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, vinyl chloride-vinyl acetate copolymer Vinyl based copolymers, ethylene-vinyl acetate copolymers, ethylene-vinyl alcohol copolymers, and mixtures thereof; polyethylene terephthalate, polybutylene terephthalate (PET), polyethylene naphthalate-isophthalate copolymers Polyester resins such as coalesced and polyester-based thermoplastic elastomers; poly (methyl) methacrylate resin, poly (meth) ethyl acrylate, poly (meth) butyl acrylate, methyl (meth) acrylate-butyl (meth) acrylate Acrylic resins such as copolymers; polyamides represented by nylon 6 or nylon 66; cellulose-based resins such as cellulose triacetate and cellophane; polystyrene; In the specification of the present invention, (meth) acrylic acid means acrylic acid or methacrylic acid. In addition, (meth) acrylate means acrylate or methacrylate.
These can be used alone or as a mixture of two or more.Polyolefins and polyester resins are preferred. Polyolefins are more preferable from the viewpoints of no generation, cost and the like, and among the polyolefins, polyethylene or polypropylene is preferable.

Further, the base layer 111 is preferably formed of a colored polyolefin. By using the colored polyolefin, it is possible to secure the stability of the color tone of the pattern layer formed on the surface of the decorative sheet, and when the surface hue of the adhered substrate to which the decorative sheet is attached is varied, The hue of the uneven surface can be satisfactorily hidden.
The colorant used for such a purpose may be appropriately selected depending on the application. For example, the base material layer 111 can be colored transparent or colored opaque. Generally, since it is necessary to cover the surface of the adherend, it is preferable that the adherend be colored and opaque. Colorants include inorganic pigments such as carbon black (black ink), iron black, titanium white, antimony white, graphite, titanium yellow, red iron oxide, cadmium red, ultramarine, cobalt blue, quinacridone red, isoindolinone yellow, nickel -Organic pigments or dyes such as azo complexes and phthalocyanine blue; metal pigments composed of scale-like foil pieces such as aluminum and brass; pearlescent pigments composed of scale-like foil pieces such as titanium dioxide-coated mica and basic lead carbonate Are used.

無機 If necessary, an inorganic filler may be added, and examples thereof include powders such as calcium carbonate, barium sulfate, clay, talc, silica (silicon dioxide), and alumina (aluminum oxide). The amount of the coloring agent to be added is generally about 1 to 80 parts by mass with respect to 100 parts by mass of the resin material forming the base material layer 111 described above.

In the present invention, in order to improve the adhesion between the resin film used for the base material layer 111 and the layer provided thereon, if necessary, a physical method such as an oxidation method or an unevenness method may be applied to one or both surfaces. Or chemical surface treatment.
Examples of the oxidation method include a corona discharge treatment, chromium oxidation treatment, flame treatment, hot air treatment, ozone / ultraviolet treatment, and the like, and examples of the unevenness method include a sand blast method and a solvent treatment method. These surface treatments are appropriately selected depending on the type of the base material, but generally, a corona discharge treatment is preferably used from the viewpoints of effects and operability.
The substrate may be subjected to a treatment such as forming a primer layer for the purpose of enhancing the interlayer adhesion between the substrate and each layer.

The base material layer 111 may contain other various additives as necessary, for example, a filler, a foaming agent, a flame retardant, a lubricant, an antioxidant, an ultraviolet absorber, and a light stabilizer. Good.

The thickness of the base layer 111 is not particularly limited, but when a sheet made of a resin (plastic) as described above is used, the thickness is usually preferably 10 to 300 μm, more preferably 30 to 100 μm. And more preferably in the range of 50 to 85 μm. When the thickness of the base material layer 111 is within the above range, the surface of the decorative sheet of the present invention is not cracked at the time of processing, and excellent processing characteristics can be obtained.

The printing layer 112 gives a design to the decorative sheet of the present invention, and may be a solid printing layer, a pattern printing layer, or a combination of a solid printing layer and a pattern printing layer. It may be. The solid printing layer is provided for the purpose of, for example, concealing the background of the base material layer 111, and is usually formed as a completely solid colored layer without a pattern. On the other hand, the pattern print layer is made up of a wood pattern, a stone pattern, a cloth pattern, a leather pattern, a natural leather surface pattern, a geometric pattern, an abstract pattern, and the like by using figures, characters, symbols, colors, combinations thereof, and the like. It has a pattern or color and is formed as a flat, uneven, or convex layer on the solid printing layer. In addition, the pattern printing layer may also function as the solid printing layer, and the printing layer 112 may be composed of only the solid printing layer or only the pattern printing layer.

As the ink composition used for forming the print layer 112, a composition in which a binder, a coloring agent such as a pigment and a dye, an extender pigment, a solvent, a stabilizer, a plasticizer, a catalyst, a curing agent, and the like are appropriately mixed is used. The binder is not particularly limited, and examples thereof include a polyurethane resin, a vinyl acetate resin, a vinyl chloride-vinyl acetate copolymer, a vinyl chloride-vinyl acetate-acrylic copolymer, a chlorinated polyethylene, and a chlorinated polypropylene. Resins, acrylic resins, polyester resins, polyamide resins, butyral resins, polystyrene resins, nitrocellulose resins, cellulose acetate resins, etc., singly or as a mixture of two or more. Used as Among them, from the viewpoint of the effect of the present invention, it is preferable to use one kind alone or a mixture of two or more kinds of polyurethane resin, vinyl acetate resin, acrylic resin, polyester resin, cellulose resin, polyamide resin and the like. preferable.
Examples of the colorant include, but are not particularly limited to, carbon black (ink), iron black, titanium white, antimony white, graphite, titanium yellow, red iron oxide, cadmium red, ultramarine, cobalt blue, and other inorganic pigments, quinacridone red, Organic pigments or dyes such as isoindolinone yellow, nickel-azo complex and phthalocyanine blue; metal pigments composed of scale-like foil pieces such as aluminum, nickel, chromium, gold, silver, copper, tin and brass; mica coated with titanium dioxide; A pearlescent (pearl) pigment composed of a scale-like foil piece such as basic lead carbonate is exemplified.

(Printed layer 112)
The print layer 112 can be generally formed by a known printing method such as gravure printing, offset printing, silk screen printing, transfer printing from a transfer sheet, and plateless printing such as ink jet printing. The pattern of the picture print layer is formed by multicolor printing using normal yellow, red, blue, and black process colors, as well as multicolor printing using special colors prepared by preparing individual color plates constituting the pattern. It is also formed by
The thickness of the printing layer 112 is usually about 1 to 20 μm, and preferably 1 to 10 μm.

印刷 The print layer 112 may be formed of a metal thin film. The metal thin film is formed using a metal such as aluminum, nickel, chromium, gold, silver, copper, tin, brass, and stainless steel by a method such as vacuum evaporation and sputtering. These may be used in combination. The metal thin film can be provided on the entire surface of the base material layer 111 or can be provided partially in a pattern.

(Adhesive layer 14)
The adhesive layer 14 is a layer provided between the printing layer 112 and a polyester-based resin layer 121 to be described later. The adhesive layer 14 is formed by an adhesive coating composed of a resin composition, a solvent, and other additives. Is done.
Examples of the resin composition include polyester resin, acrylic resin, epoxy resin, urethane resin, and rubber-based resin. Among them, a polyester resin is preferably used. By employing a polyester resin as the resin composition, the adhesive strength between the base material layer 111 and the polyester-based resin layer 121 is improved, and the decorative sheet of the present invention can be made thinner. As the polyester resin preferably employed as the resin composition, those obtained by reacting at least one of each of a polyvalent carboxylic acid and an alcohol component are preferably exemplified.

Examples of the polycarboxylic acid include aliphatic dicarboxylic acids such as succinic acid, adipic acid, sebacic acid and dodecanedicarboxylic acid; unsaturated aliphatic acids such as fumaric acid, maleic acid, itaconic acid, hexahydrophthalic acid, and tetrahydrophthalic acid; Alicyclic dicarboxylic acids; aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid; aromatic oxycarboxylic acids such as oxybenzoic acid and hydroxyethoxybenzoic acid; and unsaturated hydroxycarboxylic acids such as linoleic acid. Can be

Examples of the alcohol component include ethylene glycol, propylene glycol, propanediol, butanediol, pentanediol, hexanediol, neopentyl glycol, diethylene glycol, dipropylene glycol, cyclohexanedimethanol, spiro glycol, phenylene glycol and its ethylene oxide adduct, bisphenol And ethylene oxide adducts and propylene oxide adducts of A, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, trimethylolethane, trimethylolpropane, glycerin, triols such as pentaerythritol, and tetraols.

Further, it is preferable to use a curing agent for the resin composition. As the curing agent, in addition to isocyanate curing agents such as aliphatic polyisocyanate, alicyclic polyisocyanate and araliphatic polyisocyanate, hexamethoxymethyl melamine, hexamethoxymethylol melamine, pentamethoxymethylol melamine, trimethylol melamine, tris Melamine-based curing agents such as methoxymethylmelamine, epoxy-based curing agents, silane coupling agents, zirconium-aluminum coupling agents, and the like are preferably exemplified. By using these curing agents, stronger adhesive strength can be obtained. From the viewpoint of obtaining stronger adhesive strength, isocyanate-based curing agents and melamine-based curing agents are preferred, and isocyanate-based curing agents are more preferred.
The amount of the curing agent used is preferably 1 to 30 parts by mass, more preferably 1 to 20 parts by mass, based on 100 parts by mass of the polyester resin.

The glass transition point (Tg) of the polyester resin is preferably in the range of −20 to 100 ° C., more preferably −10 to 90 ° C. Here, the glass transition point (Tg) is a value measured by a differential scanning calorimeter (DSC).
Further, the elastic modulus is preferably in the range of -0.8 to 4 MPa, more preferably 1 to 3 MPa. Here, the elastic modulus is a value obtained by measuring a stress when an elongation of 100% or more is given in accordance with JIS K6732.

The solvent used for the adhesive coating agent that forms the adhesive layer 14 is not particularly limited, and examples thereof include toluene, xylene, ethyl acetate, butyl acetate, methyl ethyl ketone, methyl isobutyl ketone, ethylene glycol monomethyl ether, and ethylene glycol monoethyl ether. Examples include water-insoluble organic solvents, water-soluble organic solvents such as methanol, ethanol, isopropyl alcohol, and normal propyl alcohol, water, and mixed solvents thereof. In addition, it is also possible to use a non-solvent type adhesive coating agent which does not use a solvent as an adhesive coating agent. Solvent-free type adhesive coating agents are environmentally friendly and are preferably used.

When a solvent is used, the adhesive coating agent for forming the adhesive layer 14 contains a resin composition and, if necessary, other additives in a solvent, and is dissolved, dispersed, and mixed by a known method. Prepared.

The adhesive layer 14 is formed by applying the adhesive coating agent described above on the print layer 112, drying and curing. As the coating method, various known methods such as roll coating, gravure coating, air knife coating, and comma coating are used. From the viewpoint of productivity, gravure coating and comma coating are preferably used.
The adhesive layer 14 is coated so that the coating amount after drying is 0.1 to 20 g / m ² , preferably about 1 to 10 g / m ² .

(Surface layer 12)
The surface layer 12 includes a polyester resin layer 121 and a surface protection layer 122. Note that the surface protective layer 122 is not essential.
(Polyester resin layer 121)
The polyester-based resin layer 121 is a layer laminated on the adhesive layer 14 from the viewpoints of protecting the printed layer 112 from abrasion, improving the surface strength of the decorative sheet, imparting a sense of painting, and the like. The polyester resin that forms the polyester-based resin layer 121 is also advantageous in terms of an environment in which the safety of organic gas generated when the manufactured decorative sheet is incinerated and disposed of is high.

Examples of the polyester resin forming the polyester resin layer 121 include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, and naphthalenedicarboxylic acid as acid components, and ethylene glycol, diethylene glycol, butanediol, and 1,4-cyclohexane as alcohol components. Copolymers obtained by an esterification reaction with an aliphatic diol such as dimethanol and hexanediol are preferred. Specific polyester resins used in the present invention include, for example, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, ethylene glycol-terephthalic acid-isophthalic acid copolymer, terephthalic acid-ethylene glycol-1,4-cyclohexanedimethanol Copolymers and various polyester-based thermoplastic elastomers can be used.

The polyester resin forming the polyester-based resin layer 121 may be colored or may be colorless and transparent, but is preferably transparent from the viewpoint of design. When coloring, it is preferably colored and transparent, and the coloring agent described in the base layer 111 can be used.
The polyester resin forming the polyester-based resin layer 121 may be unstretched or stretched, but is preferably biaxially stretched from the viewpoint of improving surface properties such as dimensional stability, strength, crystallinity, or solvent resistance. Is preferred. Further, in the present invention, since the specularity is important, from the viewpoint of imparting excellent specularity to the decorative sheet, biaxially stretched one crystallized by stretching orientation is preferable.

The transparency (haze) of the polyester resin forming the polyester resin layer 121 is preferably 0 to 5%, more preferably 0 to 3%. Here, the haze is a value measured according to JIS K7105. When the haze of the polyester resin is within the above range, excellent design properties can be obtained.
The heat shrinkage of the polyester resin forming the polyester resin layer 121 is preferably 0 to 5%, more preferably 0 to 3%. Here, the heat shrinkage is a value measured according to JIS C2318. When the heat shrinkage is within the above range, excellent surface properties can be obtained.

Known additives such as a filler, an ultraviolet absorber, a light stabilizer, a matting agent, an antioxidant, and an anti-blocking agent are added to the polyester resin forming the polyester-based resin layer 121, if necessary. .

The polyester-based resin layer 121 is formed on the adhesive layer 14 by a method of laminating a polyester resin film formed in advance by various lamination methods such as dry lamination or thermal lamination, or other known methods. Among them, a method of forming a resin film in advance and performing dry lamination is preferable. Further, in order to improve the adhesiveness, a corona treatment or the like can be performed in addition to the formation of an easily adhesive layer described later.

The thickness of the polyester-based resin layer 121 is arbitrary, but is preferably 50 to 100 μm, and more preferably 60 to 80 μm. When the thickness of the polyester-based resin layer 121 is within the above range, the decorative sheet of the present invention can be made thinner, so that excellent processing characteristics can be obtained, and cracks and the like do not occur on the sheet surface when processed. Thus, a decorative plate having an excellent appearance can be obtained.
The total thickness of the base material layer 111 and the polyester resin layer 121 is preferably 100 to 180 μm, more preferably 110 to 160 μm, and further preferably 120 to 140 μm. When the total thickness of the base material layer 111 and the polyester-based resin layer 121 is within the above range, excellent processing characteristics are obtained, and when processed, no cracks or the like are generated on the sheet surface, and an excellent appearance is obtained. Can be obtained.

(4) The surface of the polyester resin layer 121 can be shaped by embossing. By forming the embossed pattern, the design of the decorative sheet can be improved. The pattern by such embossing is not particularly limited as long as it is a pattern corresponding to the use of the decorative sheet. For example, wood grain conduit grooves, wood grain annual ring irregularities, floating annual ring irregularities, wood grain irregularities, sand grain, satin texture, hairline, parallel grooves, stone surface irregularities such as granite cleavage planes, cloth grain surface texture, leather squeezing, letters, geometric A pattern such as a learning pattern may be used. In the case where the surface has sharpness, it is possible to further improve the smoothness by applying pressure using a mirror roll.

(Surface protection layer 122)
The surface protective layer 122 is a layer provided for imparting excellent mirror surface properties to the decorative sheet of the present invention, as well as surface properties such as friction resistance, scratch resistance, stain resistance, and chemical resistance.
The surface protective layer 122 needs to have a coating film elongation of 10 to 30%, and preferably 10 to 25%. If the elongation percentage of the coating film is less than 10%, the processing characteristics deteriorate, and if it exceeds 30%, the surface characteristics deteriorate. Here, the coating film elongation is determined by gravure printing an ionizing radiation-curable resin on a polypropylene resin sheet (thickness: 60 μm) so that the thickness after drying is 5 μm, and irradiating an electron beam ( Pressurizing voltage: 175 kV, irradiation dose: 30 kGy) The elongation rate of a sheet formed by cross-linking and curing was measured in accordance with JIL K7113-1995 (using No. 2 test piece, test temperature: 23 ° C, Test speed: 50 mm / min ± 10%). Since the surface protective layer 122 has a predetermined elongation, the decorative sheet of the present invention can be provided with excellent processing characteristics.

The surface protective layer 122 is made of a suitable material from conventionally known surface coatings according to the desired surface appearance (gloss, haze, color tone, etc.) and surface physical properties (scratch resistance, stain resistance, weather resistance, etc.). And those having a film thickness may be selected.
A typical material for the surface protective layer 122 is a layer formed by crosslinking and curing an ionizing radiation-curable resin composition or a thermosetting resin composition. Specifically, it can be appropriately selected from polymerizable monomers and polymerizable oligomers conventionally used as ionizing radiation-curable resins.

As the polymerizable monomer, a (meth) acrylate monomer having a radical polymerizable unsaturated group in the molecule is preferable, and among them, a polyfunctional (meth) acrylate monomer is preferable. The polyfunctional (meth) acrylate monomer is a (meth) acrylate monomer having two or more ionizing radiation-curable functional groups in a molecule and having at least a (meth) acryloyl group as the functional group. Bifunctional (meth) acrylates such as ethylene glycol di (meth) acrylate, bisphenol A tetraethoxy diacrylate, bisphenol A tetrapropoxy diacrylate and 1,6-hexanediol diacrylate; trimethylolpropane tri (meth) acrylate, penta Erythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol Hexa (meth) acrylate, trifunctional (meth) acrylates such as isocyanuric acid-modified tri (meth) acrylate.
From the viewpoint of improving processing characteristics and scratch resistance, the number of functional groups of the polyfunctional (meth) acrylate monomer is preferably 2 or more, 8 or less, more preferably 2 or more, 6 or less, still more preferably 2 or more and 4 or less. Even more preferably 3 or less. These polyfunctional (meth) acrylate monomers may be used alone or in combination of two or more. Further, one or more of these polyfunctional (meth) acrylate monomers and one or more of (meth) acrylate oligomers described below may be used in combination.

Examples of the polymerizable oligomer include a (meth) acrylate oligomer having two or more ionizing radiation-curable functional groups in a molecule and having at least a (meth) acryloyl group as the functional group. For example, a urethane (meth) acrylate oligomer, an epoxy (meth) acrylate oligomer, a polyester (meth) acrylate oligomer, a polyether (meth) acrylate oligomer, a polycarbonate (meth) acrylate oligomer, an acrylic (meth) acrylate oligomer, and the like can be given.
Further, as the polymerizable oligomer, a polybutadiene oligomer having a highly hydrophobic polybutadiene (meth) acrylate oligomer having a (meth) acrylate group in a side chain thereof and a silicone (meth) acrylate oligomer having a polysiloxane bond in a main chain are also used. Aminoplast resin (meth) acrylate oligomer modified from aminoplast resin with many reactive groups in a small molecule, or in novolak type epoxy resin, bisphenol type epoxy resin, aliphatic vinyl ether, aromatic vinyl ether, etc. And oligomers having a cationically polymerizable functional group.

These polymerizable oligomers may be used alone or in combination of two or more. From the viewpoint of improving processing characteristics, scratch resistance and weather resistance, urethane (meth) acrylate oligomer, epoxy (meth) acrylate oligomer, polyester (meth) acrylate oligomer, polyether (meth) acrylate oligomer, polycarbonate (meth) acrylate oligomer And acrylic (meth) acrylate oligomers are preferred, urethane (meth) acrylate oligomers and polycarbonate (meth) acrylate oligomers are more preferred, and urethane (meth) acrylate oligomers are even more preferred.
The number of functional groups of these polymerizable oligomers is preferably 2 or more and 8 or less from the viewpoint of improving processing characteristics and abrasion resistance and weather resistance, and the upper limit is more preferably 6 or less, still more preferably 4 or less. Even more preferably 3 or less.
Further, the weight average molecular weight of these polymerizable oligomers is preferably 2,500 or more and 7,500 or less, more preferably 3,000 or more, 7,000 or less, from the viewpoint of improving processing characteristics, scratch resistance, and weather resistance. , 3,500 or more and 6,000 or less. Here, the weight average molecular weight is an average molecular weight measured by GPC analysis and converted into standard polystyrene.

A monofunctional (meth) acrylate may be used in the ionizing radiation-curable resin composition for the purpose of, for example, reducing the viscosity of the ionizing radiation-curable resin composition. These monofunctional (meth) acrylates may be used alone or in combination of two or more.
When the ionizing radiation-curable composition is ultraviolet or visible light-curable, the composition preferably contains additives such as a photopolymerization initiator and a photopolymerization accelerator.
Examples of the photopolymerization initiator include one or more selected from acetophenone, benzophenone, α-hydroxyalkylphenone, Michler's ketone, benzoin, benzyldimethylketal, benzoylbenzoate, α-acyl oxime ester, thioxanthone, and the like.
The photopolymerization accelerator is capable of reducing the inhibition of polymerization by air during curing and increasing the curing speed. Examples thereof include isoamyl p-dimethylaminobenzoate and ethyl p-dimethylaminobenzoate. One or more selected ones are mentioned.
As the ionizing radiation, an electromagnetic wave such as an ultraviolet ray, a visible ray, or an X-ray, or a charged particle beam such as an electron beam, an α-ray, or various ion beams can be used. Usually, an ultraviolet ray or an electron beam is used.

Examples of the thermosetting resin composition include a two-component curable urethane resin having a polyol compound as a main component and an isocyanate compound as a curing agent (crosslinking agent), an epoxy resin, a melamine resin, a phenol resin, an unsaturated polyester resin, a melamine resin, and fluorine. Resins, silicon resins and the like.
The film thickness of the surface protective layer 122 can be in the range of about 1 to 100 μm.

(Adhesive layer 13)
The adhesive layer 13 is laminated on the surface of the decoration layer 11 opposite to the polyester resin layer 121 (the lower surface in FIG. 1, which is also referred to as the back surface of the decoration layer 11). And a layer having adhesiveness to an adherend such as a wall surface. The adhesive layer 13 has a plurality of concave shapes 13a opened on both sides thereof, that is, on the side in contact with the decorative layer 11 and on the side in contact with the peelable base sheet 15. Further, the adhesive layer 13 has elasticity, and since the plurality of concave shapes 13a each act as a fine suction cup, the adhesive layer 13 can exhibit an adhesive force (adsorbing force) to various adherends ( FIG. 2 (c)).

The adhesive layer 13 is formed, for example, by using a liquid resin composition (acryl emulsion) disclosed in Patent Document 2 (Japanese Patent Application Laid-Open No. 2017-36404) by a manufacturing method described later. Examples of the resin composition used for the adhesive layer 13 include 2-ethylhexyl polyacrylate as a main component, sulfur and bicine: N, N-Bis (2-hydroxyethyl) glycine, N.I. N. Those containing dimethyloctadecamine or the like can be used.

The thickness of the adhesive layer 13 is desirably 1 μm or more and 500 μm or less. When the thickness is below the lower limit of the above-mentioned layer thickness range, it is difficult to form a concave shape, or the size of the concave shape becomes too small, so that the adhesion (adsorption) characteristics deteriorate. On the other hand, when the thickness exceeds the upper limit of the above-mentioned thickness range, the flexibility of the decorative sheet is reduced and workability is deteriorated.
Further, in order to uniformly provide the concave shape 13a on both surfaces of the adhesive layer 13, the thickness t of the adhesive layer 13 is desirably in the range of 20 μm ≦ t ≦ 40 μm. This will be described later.

The size (diameter) and density of the concave shape 13a of the adhesive layer 13 can be adjusted by changing various conditions in a manufacturing process described later. For example, the density of the adhesive layer 13 can be used as an index indicating the degree to which the concave shape 13a is included in the adhesive layer 13. The density of the adhesive layer 13 is not particularly limited, but may be, for example, 0.1 g / cm ³ or more and 0.7 g / cm ³ or less. Further, the size (diameter) of the concave shape 13a is not particularly limited, but may be, for example, 1 μm or more and 300 μm or less. When the concave shape 13a can be regarded as a sphere, the size of the concave shape 13a is the size of the concave shape 13a. If the concave shape 13a cannot be regarded as a sphere, the diameter of the sphere having the same volume as the concave shape 13a is set to the size of the concave shape 13a.

(Releasable base sheet 15)
The peelable substrate sheet 15 is laminated on the side of the adhesive layer 13 opposite to the decorative layer 11 (the lower side in FIG. 1, which is also referred to as the back side of the adhesive layer 13). . The releasable base sheet 15 is provided in consideration of the handling property until the decorative sheet 1 is used. When the decorative sheet 1 is used, that is, the decorative sheet 1 is attached to the surface of the adherend. When peeled off. As the releasable base sheet 15, various types of conventionally known release films, separate papers, separate films, release films, release papers and the like can be appropriately used. For example, high quality paper, coated paper, impregnated paper, plastic film or the like having a release layer formed on one or both sides may be used. The release layer is not particularly limited as long as it has a release property, and examples thereof include a silicone resin, an organic resin-modified silicone resin, a fluorine resin, an aminoalkyd resin, a melamine resin, an acrylic resin, and a polyester resin. Can be mentioned. These resins can be used in any of an emulsion type, a solvent type and a solventless type. When a release film having a release layer is used, for example, a silicone release type PET (polyethylene terephthalate) film, an untreated PET film, a PP film, a silicone release type paper, or the like can be used.

The thickness of the releasable base material sheet 15 is preferably, for example, 10 μm or more and 100 μm or less, and more preferably 20 μm or more and 60 μm or less. When the thickness is below the lower limit of the above-mentioned layer thickness range, there is no stiffness and it becomes difficult to peel off. On the other hand, when the thickness exceeds the upper limit of the above-mentioned thickness range, the stiffness is too strong and the workability at the time of sticking is reduced.
Further, as the peelable substrate sheet 15, a commercially available one may be used. For example, a 38 μm-thick polyester film (Mitsui Chemicals Tosello Co., Ltd.) having one surface subjected to an easy peeling treatment with a silicone-based release agent is used. And trade name: SP-PET-01).
Note that, in the present embodiment, an example in which the releasable base material sheet 15 is provided is illustrated, but the releasable base material sheet 15 may be omitted depending on the usage form.

Note that a primer layer may be provided between the respective layers as necessary to improve the bonding strength between the respective layers. As the primer layer, when the decorative layer 11 is a polyolefin, polyester resin, vinyl chloride resin, or the like, a two-pack curable urethane resin containing a polyol and an isocyanate and using isocyanate as a curing agent, or vinyl chloride using isocyanate as a curing agent -A vinyl acetate copolymer resin or the like can be used.

FIG. 2: is sectional drawing which shows the form at the time of use of the decorative sheet 1 sequentially in detail.
The decorative sheet 1 described above includes a peelable base sheet 15 as shown in FIG. When attaching the decorative sheet 1 to the adherend 50, the peelable base sheet 15 is peeled off (FIG. 2B). Then, the exposed pressure-sensitive adhesive layer 13 is attached to the adherend 50, and by applying an appropriate pressure to the surface thereof, a large number of concave shapes 13a existing on the exposed surface of the pressure-sensitive adhesive layer are elastically deformed. By the same action as described above, it is adsorbed (adhered) to the adherend 50 (FIG. 2C).
That is, due to the elastic deformation around the concave shape 13a, a force is applied to the concave shape 13a to return to the original shape from the deformed state. Due to this force, the sealed space in the concave shape 13a becomes a negative pressure, and an adsorption action to the adherend 50 occurs. Although the suction force of the concave shape 13a alone is weak, a necessary suction force can be secured as a whole because a large number of the concave shapes 13a are formed. In addition, when the adhesive layer 13 is manufactured, if the amount of the concave shape 13a is adjusted, for example, using the density as a parameter, the adhesive force (adsorption force) of the adhesive layer 13 can be adjusted.

FIG. 3 is a perspective view showing a form in which the decorative sheet 1 is wound in the form of a roll 1R.
The decorative sheet 1 of the present embodiment can be manufactured and distributed as a form wound in the form of a roll 1R, for example, as shown in FIG. In such a form, after a required amount of decorative sheet 1 is unwound from roll 1R as shown in FIG. 3 according to the adherend to be pasted, it is cut into a required size and shape. Can be used. In addition, it is possible to prevent bending during distribution. In addition, the decorative sheet 1 is not limited to the form wound in the form of the roll 1 </ b> R, and may be in the form of a single sheet.
Such a roll 1R usually winds up the decorative sheet 1 around a winding shaft 1S such as a paper tube as shown in FIG. 3, but it is also possible to wind up the decorative sheet 1 alone without the winding shaft 1S. The decorative sheet 1 constituting the roll 1 </ b> R may be configured to include the peelable base sheet 15 or may be configured not to include the peelable base sheet 15. In order to smoothly unwind the sheet 1 and to prevent a change in the phase appearance such as gloss due to the interaction between the surface of the surface layer 12 and the adhesive layer 13, the decorative sheet 1 including the peelable base sheet 15 is used. Is preferably wound to form a row 1R.

Next, a method for manufacturing the decorative sheet 1 will be described.
FIG. 4 is a diagram illustrating a manufacturing apparatus for the decorative sheet 1.
FIG. 5 is a diagram illustrating a method for manufacturing the decorative sheet 1.

In order to manufacture the decorative sheet 1, first, a composition of an acrylic emulsion disclosed in Patent Document 2 for forming the adhesive layer 13 is put into a stirrer 301, and nitrogen is added to the composition via a pipe 302. Stirring is performed while mixing the gas to prepare the bubble-containing composition 130 including the bubble B in the composition (P1: foaming step in the figure).

Next, the bubble-containing composition 130 is coated on the releasable base material sheet 15 with a coating device 303 to form a liquid coating layer 130CL of the bubble-containing composition 130 (P2 in the figure: coating step). ). In the coating step, for example, a comma coater can be used as a coating device (coating unit), but other known coating methods may be used.

After applying the liquid coating layer 130CL of the cell-containing composition on the peelable base sheet 15, the liquid coating layer 130CL passes through the base sheet 14 coated with the cell composition 130 in the drying device 304. By drying while heating, the adhesive layer 13 is formed as the solidified coating layer 130CS of the bubble-containing composition (P3 in the figure: drying step). In the drying step, for example, a drying furnace in which the internal atmosphere temperature is about 60 ° C. to 140 ° C. can be used. The drying time may be, for example, about 30 seconds to 10 minutes. In the drying step, drying may be promoted while blowing high-temperature air at a predetermined temperature to the bubble-containing composition 130. Further, other drying methods such as infrared radiation and dielectric heating can be adopted. By performing the drying step, the openings having the same or substantially the same average diameter are formed on the exposed surface side (upper side in FIG. 5) of the solidified coating layer 130CS of the cell-containing composition 130 and on both surfaces of the releasable base material sheet 15 side. Is formed, and the adhesive layer 13 is formed. In the concave shape 13a, among the bubbles contained in the bubble-containing composition 130, the bubbles near the exposed surface side break, and a part of the bubble shape remains on the exposed surface side of the solidified coating layer 130CS. On the other hand, bubbles collected at the interface between the solidified coating layer 130CS and the peelable substrate sheet 15 and in the vicinity thereof are solidified by the solidification of the bubble-containing composition, whereby the interface shape with the solidified air bubbles in the composition is fixed. It is formed by this. Here, if the bubbles are broken in a state where the curing of the bubble-containing composition 130 is insufficient, the concave shape 13a hardly remains. On the other hand, if the bubble-containing composition 130 is cured before the bubbles break, the concave shape 13a may not be formed. Therefore, it is desirable that the drying step is performed under the condition that the foaming is performed in a state where the curing of the bubble-containing composition 130 has progressed to some extent. Therefore, the temperature and the amount of air blow in the drying process greatly affect the state of the concave shape 13a.

After the adhesive layer 13 is formed on the peelable substrate sheet 15 by a drying process, the decorative layer 11 and the surface layer 12 separately prepared are joined to the adhesive layer 13 by using a laminating apparatus 305 (P4 in the figure: laminating step). ). In the laminating step, since the lamination is performed by the attraction force (adhesion force) of the concave shape 13a of the adhesive layer 13, heating is not required, and the bonding can be performed with only a small pressing force. Therefore, the decorative layer 11 and the surface layer 12 are not damaged.

When the laminating step is completed, the decorative sheet 1 is completed.
As described above, in the production of the decorative sheet 1 of the present embodiment, the decorative sheet 1 can be efficiently produced without damaging the decorative layer 11 and the surface layer 12 by the heat at the time of forming the adhesive layer 13. The decorative sheet may then be wound into a roll or cut into a required size.

Next, an example in which the decorative sheet 1 of the present embodiment is actually produced will be shown, and results of comparison with a comparative example will be described.
In the decorative sheet 1 of the example, a biaxially stretched PET film having releasability is used as the releasable base sheet 15, and a bubble-containing composition that has been subjected to a foaming step using a comma coater having a clearance of 200 μm thereon. 130 were applied. This was dried in a drying path at 100 ° C. for 1 minute to form an adhesive layer 13, and the decorative layer 11 and the surface layer 12 were laminated to obtain a decorative sheet 1. The density of the adhesive layer 13 in this case was 0.58 g / cm3, and the thickness was 50 μm.
FIG. 6 is an enlarged photograph of the pressure-sensitive adhesive layer 13 of the decorative sheet 1 according to the example viewed from the back side (adhesive side).
FIG. 7: is the figure which expanded the cross section of the direction orthogonal to a sheet surface about the back surface side (adhesive surface side) vicinity part of the adhesive layer 13 of the decorative sheet 1 of an Example.
As shown in FIGS. 6 and 7, it can be confirmed that the adhesive layer 13 has a large number of concave shapes 13 a.
In the present specification, the sheet surface refers to a surface of each sheet that is in a plane direction of the sheet when viewed as a whole sheet. In FIG. 1, the front surface or the back surface of the decorative layer 11, or any surface parallel to these surfaces corresponds to the sheet surface.

As Comparative Example 1, a decorative sheet was prepared in the same manner as in the above example except that the foaming step was not performed. The density of the pressure-sensitive adhesive layer after preparation was 0.87 g / cm3, and the thickness was 100 μm.
As Comparative Example 2, a decorative sheet (acrylic adhesive A type) prepared by applying an acrylic resin, SK2094, manufactured by Soken Chemical Co., Ltd. without a foaming step to prepare an adhesive layer was prepared.
As Comparative Example 3, a decorative sheet (to be referred to as an acrylic adhesive B type) was prepared by applying an acrylic resin, SK1502C, manufactured by Soken Chemical Co., Ltd. without a bubbling step to produce an adhesive layer.

The above four types of decorative sheets were prepared, and the peeling force was compared.
FIG. 8 is a diagram illustrating the peeling force of the example and the comparative example.
The peeling force in FIG. 8 is a result of measuring the peeling force at that time by performing 180 ° peeling at a pulling speed of 300 mm / min using a tensile tester. The peeling force was measured immediately after the application (0.5 hours) and after 1000 hours from the application.

In the examples, it can be seen that the peeling can be performed with a relatively small peeling force both immediately after the application and after the lapse of 1000 hours. With this level of peeling force, there is no spontaneous peeling, and it is possible to easily peel off by applying a force to peel. In addition, since the adsorption is performed by the concave shape 13a, the adhesive layer 13 does not remain on the surface of the test adherend that is regarded as the adherend 50 after peeling, and the adhesive force (peeling force) of the adhesive layer 13 itself. There was no substantial change, and re-pasting was possible.
In Comparative Example 1, a small piece can be peeled with a relatively small peeling force, but a large size requires a certain force for peeling. Further, after peeling, a residual adhesive layer was observed on the adherend surface, and complete reattachment was impossible.
Comparative Example 2 requires a certain amount of force for peeling in the case of a large size, and can be peeled immediately after pasting, but after 1000 hours, the peeling force increases significantly. The decoration layer 11 and the surface layer 12 may be in a state where it is difficult to peel off by hand, or the decoration layer 11 and the surface layer 12 may be damaged if peeled off forcibly.
In Comparative Example 3, the peeling force was too large immediately after the application, and it was difficult to peel off by hand, or the decoration layer 11 and the surface layer 12 might be damaged if peeled off forcibly. .
Further, in both Comparative Examples 2 and 3, after peeling, the adhesive material partially remains on the test adherend or the adhesive strength is reduced, so that it is suitable for re-attaching. Did not.

(Verification experiment on concave shape 13a of adhesive layer 13)
As described above, in the present invention, the concave shape 13a of the adhesive layer 13 has a large effect on the adhesive strength. If the concave shape 13a is not evenly provided on both surfaces of the adhesive layer 13, there is a possibility that one surface of the adhesive layer has reduced or increased adhesive force (adhesive force) as compared with the other surface. In addition, since the concave shape 13a is uniformly provided on both surfaces of the adhesive layer 13, the physical properties of the adhesive layer 13 are also uniform, and the decorative layer 11 and the peelable substrate sheet, or the decorative layer 11 and the adherend It is also preferable from the viewpoint of sufficient adhesion to both of them and releasability from the adherend.

In order to uniformly provide the concave shape 13a on both surfaces of the adhesive layer 13, it is important to control the application amount (layer thickness t) of the adhesive layer 13. In this regard, Patent Document 2 (Japanese Patent Application Laid-Open No. 2017-36404) does not consider at all, and states that it is only necessary to form a micro sucker. In Patent Document 2, in FIG. 2 (FIG. 2 of Patent Document 2) which is a cross-sectional photograph of Example 1 formed with a WET film thickness of 800 μm, a portion shown as a surface having a micro suction cup has a fine suction cup structure. However, in the portion shown as a surface peeled from the glass substrate, a structure that seems to be a huge bubble that is incomparable with the fine suction cup structure can be confirmed. That is, in the configuration of Patent Document 2, a micro suction cup (corresponding to the concave shape 13a in the present embodiment) is formed on one surface of the adhesive layer, but the micro suction cup (concave shape 13a) is formed on the other surface. Are not substantially formed.

In this regard, the applicant also conducted a verification experiment.
As a verification experiment, four types of samples of the adhesive layer were prepared, and the concave shapes 13a on both surfaces thereof were observed by SEM. The samples are the following four types.
Sample 1: adhesive layer thickness t = 25 μm
Sample 2: adhesive layer thickness t = 30 μm
Sample 3: adhesive layer thickness t = 35 μm
Sample 4: adhesive layer thickness t 層 2000 μm
In addition, the layer thickness of the sample is a layer thickness after drying. For Samples 1 to 3, the foam-containing composition after the foaming treatment was applied to the glass surface using a coater, and the drying treatment was performed using a drying oven at 100 degrees. Sample 4 was applied dropwise onto the glass surface and air-dried at room temperature (room temperature 20 ° C.). The reason for changing the drying conditions for Sample 4 is also to verify the description in Patent Document 2 that normal temperature drying is sufficient. In each sample, the density of the pressure-sensitive adhesive layer after the foaming treatment was 0.4 g / cm ³ .

FIG. 9 is a diagram showing observation results of Sample 1.
FIG. 10 is a diagram showing the observation results of Sample 2.
FIG. 11 is a diagram showing the observation results of Sample 3.
FIG. 12 is a diagram showing an observation result of Sample 4.
As shown in FIG. 9 to FIG. 11, it was confirmed that the fine concave shapes 13a were uniformly formed on both surfaces of the samples 1 to 3 in which the thickness t of the adhesive layer was controlled and heated and dried. .
On the other hand, in Sample 4 shown in FIG. 12 where the film thickness is large and dried at room temperature, an extreme difference is recognized in the size of the concave shape 13a between the dried surface and the glass side surface, as in FIG. Results were obtained.
Therefore, it can be determined that the thickness t of the adhesive layer 13 is desirably in the range of 20 μm ≦ t ≦ 40 μm in order to uniformly provide the concave shapes 13 a on both surfaces of the adhesive layer 13.

Here, it is desirable that the state in which the concave shapes 13a are evenly provided on both surfaces of the adhesive layer 13 more specifically satisfy the following relationship.
The average value of the diameter of each opening of the concave shape 13a opening on the surface on the side of the decorative layer 11 is ^Dave _1, and each opening of the concave shape 13a opening on the side of the peelable substrate sheet (the side opposite to the decorative layer). When the average value of the diameter of the part is ^Dave ₂ ,
| D ^ave ₁ -D ^ave ₂ | / D ^ave ₂ ≦ 0.5
It is desirable to satisfy the relationship
Also,
| D ^ave ₁ −D ^ave ₂ | / D ^ave ₂ ≦ 0.25
It is more desirable to satisfy the following relationship.
By satisfying these relationships, it is possible to reduce the difference in the adhesive strength between the two surfaces of the adhesive layer, and it is also sufficient for both the decorative layer 11 and the peelable substrate sheet, or both the decorative layer 11 and the adherend. A good adhesive strength and removability from the adherend can be satisfactorily exhibited.

利 By reducing the difference in adhesive strength between the two surfaces of the adhesive layer, the convenience of the decorative sheet 1 can be significantly improved. That is, since there is no difference in the adhesive strength between both surfaces of the adhesive layer, it becomes easy to adjust necessary adhesive strength according to the specific usage of the decorative sheet 1. For example, when the adhesion between the adherend to which the decorative sheet 1 is adhered and the adhesive layer is strong, when the decorative sheet 1 is peeled off, the decorative sheet 11 is peeled off at the interface between the decorative layer 11 and the adhesive layer 13, so-called “glue”. There is a possibility that "the rest" may occur. In such a case, it is possible to easily adjust the balance of the adhesive force by performing a primer treatment on the adherend side in advance to reduce the adhesive force.

In addition, the average value of the diameters of the respective apertures is not practically possible to obtain the average of all the apertures. Therefore, in this case, the aperture having the larger diameter within the observation range of 1500 μm × 1100 μm is used. The diameter of each of the three openings was measured in order from, and the average value was obtained.

Here, the openings of the samples shown in FIGS. 10 to 13 were measured, and | D ^ave ₁ −D ^ave ₂ | / D ^ave ₂ was obtained. As a result, sample 1: 0.04 and sample 2: 0.06 , Sample 3: 0.12 and sample 4: 0.69.
The above-described method is an example of a method of calculating the average value of the diameters of the openings, and it is desirable to appropriately optimize the method according to the actual form of the adhesive layer 13. For example, an unusual opening such as an opening having an extremely large diameter or an opening having a distorted opening shape may be excluded from the calculation of the average value. Also, instead of using three samples in order from the opening having the largest diameter, up to three openings in order from the opening having the larger diameter are excluded, and the openings having the larger sizes may be used as samples for calculating the average value. Good. In addition, the number of samples N may be more than three to improve the accuracy.
Note that the determination of the number N of samples when obtaining the average value is performed by determining the standard deviation σ (D ^ave ₁ (N)) of the average values D ^ave ₁ (N) and D ^ave ₂ (N) in the number N of samples. σ (D ^ave ₂ (N)) may be determined as the minimum number of samples judged to be sufficiently converged with the increase in N. In a normal case, 3 ≦ N ≦ about 100, preferably about 10 ≦ N ≦ 30.

As described above, the decorative sheet 1 of the present embodiment has a plurality of concave shapes based on bubbles formed on both surfaces of the adhesive layer 13. Thus, the decorative sheet can be formed by providing the adhesive layer 13 without heating the polyester-based resin layer 121, and can be easily manufactured without damaging the polyester-based resin layer 121.
In addition, since the adhesive force of the adhesive layer 13 is based on the suction force of the concave shape 13a, the reworking property is high, and even if the attachment fails, it is easy to re-stretch and easy to use.
Further, since the concave shape 13a has a fine size and is provided in a large number, even if there is some unevenness on the surface of the adherend, it can exert an adhesive force (adsorbing force).
Furthermore, since the phenomenon such as adhesive residue does not occur on the surface of the adherend after the decorative sheet 1 has been peeled off, it is not necessary to clean, and it can be re-applied as it is, thus improving workability. Good.
In addition, since the decorative sheet 1 of the present embodiment can form the adhesive layer 13 without heating, it uses various forms of the decorative layer 11 and the surface layer, including the heat-sensitive decorative layer 11 and the surface layer. Thus, a decorative sheet can be formed.
(Application)
The decorative sheet 1 according to the present embodiment and other embodiments is applied to the entire surface of the surface of various materials or the surface of a partial area, and is used as an interior material and a chest for decorating the surface of a building wall, floor, ceiling, or the like. It can be used for various purposes such as furniture such as cupboards and desks, doors, sliding doors, surroundings, waist walls and other fittings and construction members, housing for home electric appliances, and interior materials for vehicles such as automobiles.
The material, that is, the adherend of the decorative sheet 1 is made of various materials such as wood, resin, metal, porcelain, glass, cement, calcium silicate, etc., and has various shapes such as a flat plate, a hollow or solid columnar body. Can be used.

(2nd Embodiment)
FIG. 13 is a sectional view showing a second embodiment of the decorative sheet.
The second embodiment and a third embodiment described later have the same configuration as the first embodiment, except that some layer configurations are omitted. Therefore, portions that perform the same functions as in the first embodiment described above are denoted by the same reference numerals, and redundant description will be omitted as appropriate.
The decorative sheet 1B of the second embodiment is a form in which the decorative layer 11 and the adhesive layer 14 are omitted from the decorative sheet 1 of the first embodiment. In this case, for example, the polyester resin layer 121 may be colored.

(Third embodiment)
FIG. 14 is a sectional view showing a third embodiment of the decorative sheet.
The decorative sheet 1C of the third embodiment is a form in which the surface protective layer 122 is further omitted from the decorative sheet 1 of the second embodiment. In such a case, for example, if the surface of the polyester-based resin layer 121 is made smooth, it is possible to provide a mirror surface even without the surface protection layer 122.

Various modifications and changes are possible without being limited to the embodiment described above, and these are also within the scope of the present invention.
In addition, although each embodiment and a modified form can be used in appropriate combination, detailed description is omitted. Further, the present invention is not limited by the embodiments described above.

1, 1B, 1C Cosmetic sheet 1R Roll 1S Winding shaft 11 Decorative layer 12 Surface layer 13 Adhesive layer 13a Concave shape 14 Adhesive layer 15 Releasable base sheet 50 Adherend 111 Base layer 112 Printing layer 121 Polyester resin layer 122 Surface protective layer 130 Bubble-containing composition 130CL Liquid coating layer 130CS Solid coating layer 301 Stirrer 302 Pipe 303 Coating device 304 Drying device 305 Laminating device

Claims (10)

1. A surface layer formed on the outermost surface and including at least a layer formed of a polyester resin,
   Laminated on the back side of the surface layer, an adhesive layer having a plurality of concave shapes on both sides,
   With
   The concave shape is formed evenly on both surfaces of the adhesive layer,
   The average value of the diameter of each of the concave-shaped openings that are open on the surface on the surface layer side is ^Dave _1, and the average value of the diameter of each of the concave-shaped openings that open on the side opposite to the surface layer is the average value. When D ^ave ₂ is set,
   | D ^ave ₁ -D ^ave ₂ | / D ^ave ₂ ≦ 0.5
   Decorative sheet that satisfies the relationship.
2. The decorative sheet according to claim 1,
   The thickness t of the adhesive layer is in the range of 20 μm ≦ t ≦ 40 μm,
   A decorative sheet characterized by the following.
3. In the decorative sheet according to claim 1 or claim 2,
   The surface layer is composed of only a layer formed of a polyester resin,
   A decorative sheet characterized by the following.
4. In the decorative sheet according to claim 1 or claim 2,
   The surface layer,
   A layer formed of a polyester resin,
   A surface protective layer formed on the surface side than the layer formed by the polyester-based resin,
   Having,
   A decorative sheet characterized by the following.
5. In the decorative sheet according to any one of claims 1 to 4,
   Arranged between the surface layer and the adhesive layer, further comprising a decorative layer including at least a pattern,
   A decorative sheet characterized by the following.
6. In the decorative sheet according to any one of claims 1 to 5,
   The outermost surface of the surface layer is configured as a mirror surface,
   A decorative sheet characterized by the following.
7. In the decorative sheet according to any one of claims 1 to 6,
   The pressure-sensitive adhesive layer is obtained by curing a liquid resin composition containing bubbles,
   The concave shape based on the air bubbles is formed on a plurality of surfaces,
   A decorative sheet characterized by the following.
8. The decorative sheet according to any one of claims 1 to 7,
   The adhesive layer has a density of 0.1 g / cm ³ or more and 0.7 g / cm ³ or less,
   A decorative sheet characterized by the following.
9. In the decorative sheet according to any one of claims 1 to 8,
   On the back side of the adhesive layer, a peelable substrate sheet is laminated,
   A decorative sheet characterized by the following.
10. The decorative sheet according to any one of claims 1 to 9,
    Being configured in a rolled form,
    A decorative sheet characterized by the following.

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