JP2022082835A - Decorative sheet manufacturing method and decorative sheet - Google Patents

Abstract

To provide a method for manufacturing a decorative sheet and the decorative sheet, the method for manufacturing a decorative sheet comprising irradiating a decorative sheet with a laser beam to form an embossed portion having irregularities thereby making it possible to eliminate embossing by using so-called an embossing roll.SOLUTION: The method comprises a first step of sequentially forming a printed picture layer 30 on which a picture is printed and a transparent polypropylene layer 40 on a surface of a colored film layer 20, a second step of irradiating a surface of the transparent polypropylene layer 40 with a laser beam 71 to form an embossed portion 41 having irregularities synchronized with the picture of the printed picture layer 30, a third step of applying a corona treatment to the surface on which the embossed portion 41 is formed, a fourth step of applying a transparent resin to the surface on which the corona treatment is applied to form a topcoat layer, and a fifth step of forming a primer layer 60 on a back surface of the colored film layer 20. A CO2 laser may be used as the laser beam 71.SELECTED DRAWING: Figure 1

Description

The present invention relates to a method for manufacturing a decorative sheet and a decorative sheet, for example, which are used indoors, are attached to the surface of fittings / building materials, and are used by matching the patterns of fittings / building materials for each house or room. By irradiating the surface of the transparent polypropylene layer with a laser beam to form an embossed portion having irregularities, it is possible to provide a method for manufacturing a decorative sheet capable of eliminating embossing using so-called embossing rolls.

Conventionally, decorative sheets used indoors are attached to the surface of fittings, construction materials, and the like. These items are used by matching the patterns of fittings and construction materials for each house or room.
In recent years, olefin-based materials have been mainly used for the decorative sheets used there due to the problem of gas during combustion. In order to protect the pattern from wear on the surface, a decorative sheet having multiple layers, printed on a colored olefin sheet, and a transparent olefin sheet bonded to the sheet is widely used.

These decorative sheets are often used with wood grain patterns or abstract patterns, but simply printing the pattern on a colored olefin sheet gives a flat sheet with a texture like real wood or stone. I can't.
For this reason, the surface of the transparent olefin sheet to be bonded on top is given an uneven shape that imitates a wood grain conduit, and the surface protection layer (top coat) on the outermost layer imitates a wood grain conduit with high and low glossy parts. By attaching it, the design that is closer to the real thing is reproduced.
In most cases, an embossed roll produced by utilizing metal corrosion or the like is used for imparting an uneven shape to the surface (see paragraphs [0023] to [0026] of Patent Document 2 and FIG. 4).

Japanese Unexamined Patent Publication No. 2011-11137

When the above-mentioned conventional embossed roll is prepared as a decorative sheet used for building materials, the width exceeds 1 m, such as 3 shaku and 4 shaku, which are mainly used for building materials, and it is sufficient so that the repeated design of the conduit does not become monotonous. It is necessary to prepare a roll with a long diameter.
In order to reproduce those embossed rolls in various tree species, there was the first problem that it was necessary to produce a considerable amount of embossed rolls.

Also, if the embossed rolls are damaged, the rolls of the consenting craftsman must be reprinted, and those embossed rolls must be replaced for each embossed sheet when making the sheet, which requires considerable time and effort. In addition, there is a second problem that it is necessary to pay sufficient attention to safety in handling heavy objects.
In view of the above-mentioned first and second problems, the present invention irradiates the surface of the transparent polypropylene layer with a laser beam to form an embossed portion having irregularities, thereby forming an embossed portion using a so-called embossed roll. Can be abolished.

As a result, the cost, time and replacement of embossed rolls can be eliminated.
It is also possible to change the embossing pattern even during sheet production, and to synchronize the embossing by reading a pattern (pitch), random shape, or pattern with a length that is not affected by the roll diameter.

The method for producing a decorative sheet according to one aspect of the present invention includes a first step of sequentially forming a printed pattern layer on which a pattern is printed and a transparent polypropylene layer on the surface of the colored film layer, and the surface of the transparent polypropylene layer. A second step of forming an embossed portion having irregularities synchronized with the pattern of the printed pattern layer by irradiating the printed pattern layer, and a third step of applying a corona treatment to the surface on which the embossed portion is formed. A fourth step of applying a transparent resin to the corona-treated surface to form a top coat layer, and a fifth step of forming a primer layer on the back surface of the colored film layer are included. It is characterized by.

Further, the method for producing a decorative sheet according to one aspect of the present invention is characterized in that the laser light uses a CO ² laser.
The decorative sheet according to one aspect of the present invention is a decorative sheet in which a printed pattern layer on which a pattern is printed and a transparent polypropylene layer are sequentially formed on the surface of the colored film layer, and a primer layer is formed on the back surface of the colored film layer. The surface of the transparent polypropylene layer is uneven formed by irradiating the surface with a laser beam, and has an embossed portion synchronized with the pattern of the printed pattern layer and a corona on the surface having the embossed portion. The treated corona processing part and
It is characterized by having a top coat layer coated with a transparent resin on the surface having the corona-treated portion.

According to one aspect of the present invention, by irradiating the surface of the transparent polypropylene layer with a laser beam to form an embossed portion having irregularities, the embossing using so-called embossing roll can be abolished.

It is sectional drawing of the decorative sheet which concerns on Embodiment 1. FIG. It is sectional drawing for demonstrating the manufacturing process of a decorative sheet corresponding to FIG. It is explanatory drawing for demonstrating the manufacturing method of the decorative sheet which concerns on Embodiment 1. FIG.

(Embodiment 1)
Embodiment 1 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 plane dimensions, the ratio of the thickness of each layer, and the like are different from the actual ones. Further, the embodiments shown below exemplify a configuration for embodying the technical idea of the present invention, and the technical idea of the present invention describes the materials, shapes, structures, etc. of the constituent parts as follows. It is not specific to things. The technical idea of the present invention may be modified in various ways within the technical scope specified by the claims described in the claims.

(Cosmetic sheet 10 according to the first embodiment)
In FIG. 1, 10 is a decorative sheet, which is not shown, but is used indoors, for example, for fittings (interior door, entrance storage), building materials (parting, peripheral edge, baseboard, window frame, door frame), etc. It is affixed to the surface and is used by matching the patterns of fittings and construction materials for each house or room.
As shown in FIG. 1, the decorative sheet 10 includes the following layers, and each layer is formed in order from (1).

The following (1) to (5) will be described later.
(1) Colored film layer 20
(2) Printed pattern layer 30
(3) Transparent polypropylene layer 40
(4) Top coat layer 50
(5) Primer layer 60
The layer structure of the decorative sheet 10 is not limited to (1) to (5) described above, and although not shown, the surface of the transparent polypropylene layer 40 on which the embossed portion 41, which will be described later, is formed is subjected to corona treatment. Forming a part.

Each layer of the decorative sheet 10 is not limited to (1) to (5) described above, and although not shown, a substrate may be adhered to the back surface side of the primer layer 60 to form a decorative board, or a primer. An adhesive layer and a release paper may be added to the back surface side of the layer 60 to form a decorative tack sheet.
Further, as shown in FIG. 2, on the surface of the transparent polypropylene layer 40, an embossed portion 41, which is an uneven surface synchronized with the pattern of the printed pattern layer 30, is formed by a laser beam 71 irradiated from the laser processing machine 70. ing.

(Main features of decorative sheet 10)
The main features of the decorative sheet 10 according to the first embodiment are as follows.
(1) As shown in FIG. 3, the method for manufacturing the decorative sheet 10 according to the first embodiment includes the following steps.
(1-1) First Step The first step is a step of sequentially forming a printed pattern layer 30 and a transparent polypropylene layer 40 on which a pattern is printed on the surface of the colored film layer 20.
(1-2) Second Step In the second step, the surface of the transparent polypropylene layer 40 is irradiated with a laser beam 71 to form an embossed portion 41 which is an uneven surface synchronized with the pattern of the printed pattern layer 30. It is a process to do.

(1-3) Third step The third step is a step of applying a corona treatment to the surface on which the embossed portion 41 is formed.
(1-4) Fourth Step The fourth step is a step of applying a transparent resin to the corona-treated surface to form a top coat layer.
(1-5) Fifth Step The fifth step is a step of forming a primer layer 60 on the back surface of the colored film layer 20.

According to the first embodiment, the embossing using the so-called embossing roll can be abolished.
As a result, the cost, time and replacement of embossed rolls can be eliminated.
It is also possible to change the pattern of the embossed portion 41 even during the production of the decorative sheet 10, and to synchronize the embossing by reading a pattern (pitch), a random shape, or a pattern having a length that is not affected by the roll diameter. ..

Further, according to the first embodiment, since the surface of the transparent polypropylene layer 40 on which the embossed portion 41 is formed is subjected to corona treatment, the wettability is generally improved, and at the same time, the printing characteristics, coating characteristics, bonding characteristics and the like are improved. Can be improved.
In addition to the corona treatment, a surface treatment such as a pretreatment for coating may be performed.

(2) Since the method for manufacturing the decorative sheet 10 according to the first embodiment uses a CO ² laser, the transparent polypropylene layer 40 is also suitable for laser processing, such as a solid-state laser processing machine, a semiconductor laser processing machine, or the like. It is cheaper than the other two types of processing machines and can reduce the manufacturing cost of the decorative sheet 10.

(3) According to the decorative sheet 10 according to the first embodiment, the embossing using the so-called embossing roll can be abolished.

(Colored film layer 20)
As shown in FIG. 1, the colored film layer 20 is located on the surface of the primer layer 60, is formed by a printing method, and is provided mainly for the purpose of imparting concealment.
The colored film layer 20 is printed with a two-component urethane resin, for example, by a gravure printing method.

(Printed pattern layer 30)
As shown in FIG. 1, the printed pattern layer 30 is located on the surface of the colored film layer 20, is formed by a printing method, and is provided for the purpose of imparting design to the decorative sheet 10.
The printed pattern layer 30 is a pattern printed with a urethane resin, for example, by a gravure printing method.
Examples of the printing method include, but are not limited to, a gravure printing method, but the printing method is not limited to this, and various printing methods such as an offset printing method, a letterpress printing method, a flexographic printing method, a screen printing method, an inkjet printing method, and an electrostatic printing method are used. The method is applicable.

The type of pattern of the printed pattern layer 30 is arbitrary depending on the purpose of use, the preference of the user, and the like, and for example, a wood grain pattern, a stone grain pattern, an abstract pattern, and the like are common. The type of the pattern is not limited to the types exemplified above, and may be, for example, solid printing on the entire surface.
As the printing ink used in the printing method, for example, vinyl acetate-based ink (cyan, magenta, yellow) is used.
The printing ink is exemplified by a urethane resin, but the printing ink is not limited to this, and for example, an organic or inorganic dye or a colorant such as a pigment may be used, and a filler, a tackifier, a plasticizer, etc. may be used. It is dispersed in a binder made of synthetic resin, etc., together with appropriate additives such as stabilizers, dispersants, defoaming agents, leveling agents, surfactants, desiccants, etc., and solvents or diluents. be.

(Transparent polypropylene layer 40)
The transparent polypropylene layer 40 serves as a support for the decorative sheet 10 and is made of a transparent olefin sheet.
As shown in FIG. 2, the transparent polypropylene layer 40 is manufactured by two types and three layers in the order of a transparent skin layer 42, a transparent polypropylene transparent core layer 43, and a transparent skin layer 42.
The transparent skin layer 42 is preferably formed by adding a dispersant as a nano-sized additive to a transparent polypropylene-based thermoplastic resin. Further, it is desirable to add an inorganic filler to the transparent skin layer 42 in addition to the dispersant as a nano-sized additive.

As the transparent polypropylene layer 40, 2 types and 3 layers are exemplified, but the present invention is not limited to this, and a single layer may be used. Even when the transparent polypropylene layer 40 is made into a single layer, it is preferably formed by adding a dispersant as a nano-sized additive or adding an inorganic filler in addition to the dispersant as a nano-sized additive. It is desirable to do.

(Embossed part 41)
As shown in FIG. 2, on the surface of the transparent polypropylene layer 40, an embossed portion 41, which is an uneven surface synchronized with the pattern of the printed pattern layer 30, is formed by a laser beam 71 irradiated from the laser processing machine 70. ..
The portion irradiated with the laser beam 71 is a concave portion, and the other portion is a convex portion on the flat surface of the transparent polypropylene layer 40.

The recess of the embossed portion 41 is formed in the shape of a fine groove, and the cross-sectional shape of the groove is formed, for example, in a rectangular shape as shown in FIG.
A rectangle is exemplified as the cross-sectional shape of the groove, but the shape is not limited to this, and although not shown, the groove may be formed in a V shape or a U shape, for example.

The laser processing machine 70 uses, for example, a CO ² laser (carbon dioxide gas laser).
For example, a case where the pattern of the print pattern layer 30 is a “wood grain pattern” will be described. The laser processing machine 70 reads data of, for example, "wood grain conduit" synchronized with the "wood grain pattern" of the printed pattern layer 30, and irradiates the surface of the transparent polypropylene layer 40 with laser light 71 based on the data. .. As a result, an embossed portion 41 having a "wood grain conduit shape" synchronized with the "wood grain pattern" of the printed pattern layer 30 is formed on the surface of the transparent polypropylene layer 40.

(Top coat layer 50)
The top coat layer 50, also referred to as a top coat, is located on the surface side of the transparent polypropylene layer 40 as shown in FIG. 1, and is formed by a printing method to impart surface physical properties such as abrasion resistance and water resistance. It is provided for the purpose of printing.
The top coat layer 50 is formed by applying an acrylic two-component curable resin (acrylic urethane resin manufactured by DIC Graphic) to the surface of the transparent polypropylene layer 40 on which the embossed portion 41 is formed so as to have a thickness of 6 μm. do.

Further, the top coat layer 50 is subjected to antiviral treatment.
As an antiviral treatment, an antiviral agent is added to the top coat layer 50. As the antiviral agent, for example, a silver-based inorganic additive (Bioside TB-B100) manufactured by Taisho Technos Co., Ltd., which carries silver ions, is used.

(Corona processing)
Further, prior to the formation of the top coat layer 50, the surface of the transparent polypropylene layer 40 on which the embossed portion 41 is formed is subjected to corona treatment, which is not shown. Form a corona treatment section. As a result, the top coat layer 50 is located on the corona processing section.
The corona treatment generally improves wettability, and at the same time, can improve printing characteristics, coating characteristics, bonding characteristics, and the like.
In addition to the corona treatment, a surface treatment such as a pretreatment for coating may be performed.

(Primer layer 60)
As shown in FIG. 1, the primer layer 60 is located on the back surface side of the transparent polypropylene layer 40, and is mainly intended for improving adhesiveness.
The functions of the primer layer 60 include, in addition to improving the adhesiveness, surface stabilization after surface treatment, anticorrosion of the metal surface, imparting adhesiveness, prevention of deterioration of the adhesive, and the like.
The primer layer 60 is formed by coating a urethane resin so that the solid content is 1 g / m ² , for example, by a gravure printing method.

(Transparent core layer 43)
The transparent polypropylene layer 40 is represented in the drawing so that the transparent core layer 43 and the transparent skin layer 42 form separate layers, but in reality, the transparent core layer 43 and the transparent skin layer 42 are continuous, and the interface is continuous. It is a single-layer sheet that does not exist.
For the transparent core layer 43, for example, a transparent polypropylene resin blended with a weather resistant agent is used.

(Transparent skin layer 42)
In addition to the dispersant as a nano-sized additive, an inorganic filler is added to the transparent skin layer 42, and a transparent polypropylene resin is used.
The transparent skin layer 42: the transparent core layer 43: the transparent skin layer 42 are simultaneously extruded so as to have a thickness ratio of 0.5: 9: 0.5 to prepare a transparent polypropylene layer 40 having a total thickness of 50 μm.

The total thickness of each of the two types and three layers of the transparent skin layer 42, the transparent core layer 43, and the transparent skin layer 42 matches the thickness of the single transparent polypropylene layer 40, for example, 70 μm. Of course, 2 types and 3 layers are exemplified, but the present invention is not limited to this, and the transparent polypropylene layer 40 may be used as a single layer.

(Resin material of transparent core layer 43)
Examples of the resin material constituting the transparent core layer 43 include a thermoplastic resin. The thermoplastic resin is not particularly limited, and the same material as the thermoplastic resin used as the base material layer or the like in the conventional decorative sheet 10 can be used.
Examples of the thermoplastic resin include polyethylene, polypropylene, polymethylpentene, polybutene, ethylene-propylene copolymers, ethylene-α-olefin copolymers, polyolefin resins such as propylene-α-olefin copolymers, polyethylene terephthalates, and the like. Polybutylene terephthalate, polytetramethylene terephthalate, polyethylene naphthalate, polyethylene terephthalate-isophthalate copolymer, 1,4-cyclohexanedimethanol copolymerized polyethylene terephthalate, polyallylate, polyester resin such as polycarbonate, ethylene-vinyl acetate copolymer Combined, ethylene-vinyl alcohol copolymer, ethylene- (meth) acrylic acid (ester) copolymer, ethylene-unsaturated carboxylic acid copolymer metal neutralized product (ionomer) and other olefin-based copolymer resins Acrylic resins such as polyolefin resins, poly (meth) acrylonitrile, polymethyl (meth) acrylates, polyethyl (meth) acrylates, polybutyl (meth) acrylates, and polyacrylamides, 6-nylon, 6,6-nylon, 6,10- Polypolymer resin such as nylon, styrene resin such as polystyrene, AS resin, ABS resin, vinyl resin such as polyvinyl chloride, polyvinyl acetate, polyvinyl alcohol, polyvinyl acetal, polyvinyl butyral, polyvinyl fluoride, vinylidene fluoride, Fluororesin such as polytetrafluoroethylene, ethylene-tetrafluoroethylene copolymer, ethylene-perfluoroalkyl vinyl ether copolymer, or a mixture of two or more of them, a copolymer, a composite, a laminate, etc. Can be used.

In particular, in view of the growing social concern about environmental problems in recent years, it is not preferable to use a chlorine (halogen) -containing thermoplastic resin such as a polyvinyl chloride resin as a thermoplastic resin, and it is a non-halogen type. It is preferable to use a thermoplastic resin.
In particular, polyester-based resin (amorphous or biaxially stretched) or polyolefin-based resin, especially polyolefin-based resin, is used as the non-halogen-based thermoplastic resin from the viewpoints of various physical properties, processability, versatility, economy, etc. It is most preferable to do. For example, as the polyolefin resin, it is preferable to use a polypropylene resin containing 30% by mass or more and 100% by mass or less of a highly crystalline homopolypropylene resin having an isotactic pentad fraction (mmmm fraction) of 95% or more.

The transparent core layer 43 may be filled with, for example, a filler, an ultraviolet absorber, a light stabilizer, a heat stabilizer, an antioxidant, an antioxidant, a lubricant, a flame retardant, an antibacterial agent, an antifungal agent, and a reduction agent, if necessary. One or more selected from various additives such as a lubricant, a light scattering agent, and a gloss adjusting agent may be added.

(Resin material of transparent skin layer 42)
Examples of the resin material constituting the transparent skin layer 42 include a thermoplastic resin. The thermoplastic resin is not particularly limited, and the same resin material as the transparent core layer 43 can be used.

(Nano-sized additives, etc. (nucleating agents))
The transparent skin layer 42 contains an inorganic filler in addition to a dispersant as a nano-sized additive, and is hereinafter also referred to as a “nano-sized nucleating agent”.
The nano-sized nucleating agent is preferably used by being added to the polypropylene resin in the form of a nucleating agent vesicle contained in a vesicle having an outer film of a single-layer film.
Further, in the first embodiment, the nucleating agent in the resin constituting the transparent skin layer 42 may be included in the vesicle with a part of the nucleating agent exposed. Since the transparent skin layer 42 contains a nucleating agent, the crystallinity can be improved, and the scratch resistance (scratch resistance) of the decorative sheet 10 can be improved.

(Diameter of nano-sized nucleating agent)
The nano-sized nucleating agent preferably has an average particle size of 1/2 or less of the wavelength region of visible light, and specifically, since the wavelength region of visible light is 400 nm or more and 750 nm or less, the average particle size Is preferably 375 nm or less.

Since the particle size of nano-sized nucleating agents is extremely small, the number of nucleating agents present per unit volume and the surface area increase in inverse proportion to the cube of the particle diameter. As a result, the distance between the nucleating agent particles becomes shorter, so that when crystal growth occurs from the surface of one nucleating agent particle added to the resin, the end where the crystal is growing is immediately one. It comes into contact with the ends of the crystals growing from the surface of the other nucleating agent particles adjacent to the nucleating agent particles, and the ends of each crystal inhibit the growth and the growth of each crystal is stopped. Therefore, the average particle size of the spherulite in the crystal portion of the crystalline resin can be made small, for example, the spherulite size can be made small to 1 μm or less.

As a result, a resin film having a high degree of crystallinity and a high hardness can be obtained, and the stress concentration between the spherulites generated during the bending process is efficiently dispersed, so that the resin suppresses cracking and whitening during the bending process. A film can be realized.

When the nucleating agent is simply added, the nucleating agent in the resin secondarily aggregates to increase the particle size.
On the other hand, when the nucleating agent vesicle is added, the dispersibility in the resin is improved, so that the number of crystal nuclei relative to the amount of the added nucleating agent is significantly increased as compared with the case where the nucleating agent is simply added. do.
Therefore, the average particle size of the spherulites in the crystal portion of the resin becomes small, and it is possible to suppress the occurrence of cracking and whitening during bending. Therefore, the crystallinity can be further increased by adding the nucleating agent vesicle, and the elastic modulus can be improved and the processability can be further achieved.

The transparent skin layer 42 is, for example, preferably 0.05 parts by mass or more and 0.5 parts by mass or less, and more preferably 0.1 parts by mass or more and 0.3 parts by mass or less with respect to 100 parts by mass of the polypropylene resin as a main component. It is formed of a resin material to which a nucleating agent is added within the range of.
When the nucleating agent vesicle is used, the amount of the nucleating agent added to the resin material is the amount converted into the nucleating agent in the nucleating agent vesicle.

If the amount of the nucleating agent added is less than 0.05 parts by mass, the crystallinity of polypropylene may not be sufficiently improved, and the scratch resistance of the transparent skin layer 42 may not be sufficiently improved.
Further, when the amount of the nucleating agent added exceeds 0.5 parts by mass, the spherulite growth of polypropylene is conversely inhibited due to the excess of crystal nuclei, and as a result, the crystallinity of polypropylene is not sufficiently improved. The scratch resistance of the transparent skin layer 42 may not be sufficiently improved.
Here, the "main component" refers to a resin material that occupies 50% by mass or more of the resin material constituting the transparent skin layer 42.

(Method of nanonizing nucleating agent)
In addition, as a method for nanonizing the nucleating agent, for example, a solid phase method in which the nucleating agent is mainly mechanically pulverized to obtain nano-sized particles, or the nucleating agent or the nucleating agent is dissolved. Methods such as the liquid phase method for synthesizing and crystallizing nano-sized particles in a solution, and the gas phase method for synthesizing and crystallizing nano-sized particles from gas and steam composed of nucleating agents and nucleating agents. It can be used as appropriate.
Examples of the solid phase method include ball mills, bead mills, rod mills, colloid mills, conical mills, disc mills, hammer mills, jet mills and the like.

Further, examples of the liquid phase method include a crystallization method, a coprecipitation method, a sol-gel method, a liquid phase reduction method, a hydrothermal synthesis method and the like. Further, examples of the gas phase method include an electric furnace method, a chemical flame method, a laser method, a thermal plasma method, and the like.

(Supercritical reverse phase evaporation method)
The supercritical reverse phase evaporation method is preferable as a method for nanonizing the nucleating agent. The supercritical reverse phase evaporation method is a method for producing a capsule (nano-sized vesicle) containing a target substance using carbon dioxide under supercritical state or temperature condition or pressure condition above the critical point.
The carbon dioxide in a supercritical state means carbon dioxide in a supercritical state having a critical temperature (30.98 ° C.) and a critical pressure (7.3773 ± 0.0030 MPa) or higher, and is under temperature conditions above the critical point or. Carbon dioxide under pressure conditions means carbon dioxide under conditions where only temperature or pressure exceeds the critical condition.

In addition, as a specific nano-ization treatment by the supercritical reverse phase evaporation method, first, the aqueous phase is injected into a mixed fluid of supercritical carbon dioxide, phospholipid as an outer film forming substance, and a nucleating agent as an encapsulating substance. Then, by stirring, an emulsion of supercritical carbon dioxide and an aqueous phase is produced.
Next, when the pressure is reduced, carbon dioxide expands and evaporates to cause phase inversion, and phospholipids generate nanocapsules (nanovesicles) in which the surface of the nucleating agent particles is covered with a monolayer film.

By using this supercritical reverse phase evaporation method, unlike the conventional encapsulation method in which the outer film is a multilayer film on the surface of the nucleating agent particles, a single-layer film capsule can be easily generated. Small diameter capsules can be prepared.
The nucleating agent vesicle is prepared by, for example, a Bangham method, an extrusion method, a hydration method, a surfactant dialysis method, a reverse phase evaporation method, a freeze-thaw method, a supercritical reverse phase evaporation method, or the like. The nucleating agent vesicle is particularly preferably prepared by using the supercritical reverse phase evaporation method.

(Adventitia constituting the nucleating agent vesicle)
The outer membrane constituting the nucleating agent vesicle is composed of, for example, a monolayer membrane. The outer membrane is composed of a substance containing a biological lipid such as a phospholipid.
In the present specification, a nucleating agent vesicle whose outer membrane is composed of a substance containing a biological lipid such as a phospholipid is referred to as a nucleating agent liposome.
Examples of the phospholipids constituting the outer membrane include phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidic acid, phosphatidylglycerol, phosphatidylinositol, cardiopine, yellow egg lecithin, hydrogenated yellow egg lecithin, soybean lecithin, hydrogenated soybean lecithin and the like. Examples thereof include glycerophospholipids, sphingomyelin, ceramide phosphorylethanolamine, ceramide phosphorylglycerol and other sphingolin lipids.

(Other substances that form the outer membrane)
Other substances that form the outer membrane of the vesicle include, for example, nonionic surfactants and dispersants such as cholesterols or a mixture of triacylglycerols thereof.
Among these, examples of the nonionic surfactant include polyglycerin ether, dialkyl glycerin, polyoxyethylene hydrogenated castor oil, polyoxyethylene alkyl ether, polyoxyethylene sorbitan fatty acid ester, sorbitan fatty acid ester, and polyoxyethylene polyoxypropylene. Copolymers, polybutadiene-polyoxyethylene copolymers, polybutadiene-poly (2-vinylpyridine), polystyrene-polyacrylic acid copolymers, polyethylene oxide-polyethylethylene copolymers, polyoxyethylene-polycaprolactum copolymers, etc. One or more of the above can be used. As cholesterols, for example, cholesterol, α-cholestanol, β-cholestanol, cholestane, desmosterol (5,24-cholestadien-3β-ol), sodium cholic acid, choleciferol and the like can be used.

Further, the outer membrane of the liposome may be formed from a mixture of a phospholipid and a dispersant.
In the decorative sheet 10 of the present embodiment, the nucleating agent vesicle is preferably a radical scavenger liposome having an outer membrane made of phospholipids, and by forming the outer membrane made of phospholipids, the decorative sheet 10 The compatibility between the resin material as the main component and the vesicle can be improved.

The nucleating agent is not particularly limited as long as it is a substance that becomes a starting point of crystallization when the resin crystallizes. Examples of the nucleating agent include phosphate ester metal salt, benzoic acid metal salt, pimelli acid metal salt, rosin metal salt, benziliden sorbitol, quinacridone, cyanine blue and talc. In particular, in order to maximize the effect of the nanonization treatment, it is preferable to use a phosphate ester metal salt, a benzoic acid metal salt, a pimelic acid metal salt, and a rosin metal salt, which are non-melted and can be expected to have good transparency. If the material itself can be made transparent by nano-treatment, colored quinacridone, cyanine blue, talc and the like can also be used. Further, the melt-type benzylidene sorbitol may be appropriately mixed and used with the non-melt-type nucleating agent.

(Characteristics of transparent skin layer 42)
As described above, the decorative sheet 10 of the first embodiment is characterized in that the transparent skin layer 42 contains a resin material and a nucleating agent.
Further, the decorative sheet 10 of the first embodiment is characterized in that when the transparent skin layer 42 is formed, a nucleating agent contained in a vesicle is added to the resin material to crystallize the resin material. is doing. By adding the nucleating agent to the resin composition in a state of being encapsulated in the vesicle, the effect of dramatically improving the dispersibility of the nucleating agent in the resin material, that is, in the transparent skin layer 42 is obtained. On the other hand, it can be said that it is impractical because it is assumed that it may be difficult to directly identify the nucleating agent contained in the vesicle by the structure and characteristics of the finished product in the state of the decorative sheet 10. .. The reason is as follows.

The nucleating agent added in the vesicle state has a high dispersibility and is in a dispersed state, and even in the state of the laminated body which is the precursor of the produced decorative sheet 10, the transparent skin layer 42 has. Highly dispersed.
However, in the process of producing the decorative sheet 10, the laminate is usually subjected to various treatments such as compression treatment and curing treatment, and such treatment causes the outer film of the vesicle containing the nucleating agent to be crushed or chemically treated. May react.

Therefore, depending on the treatment step of the decorative sheet 10, the outer film of the nucleating agent in the completed decorative sheet 10 is crushed or the state of chemical reaction varies, and the nucleating agent is included (foreskin) in the outer film. There is a high possibility that it has not been done.
If the adventitia is not included in the adventitia, it is difficult to specify the physical characteristics of the adventitia itself in the numerical range, and is the constituent material of the crushed adventitia the outer membrane of the vesicle? It may be difficult to determine whether the material was added separately from the nucleating agent.

As described above, the present disclosure is added in the state of a vesicle containing the nucleating agent, although there is a difference in that the nucleating agent is blended in a high dispersion with respect to the decorative sheet 10 as compared with the conventional case. In the state of the decorative sheet 10, it is assumed that it is impractical to specify the structure and characteristics of the decorative sheet 10 within the numerical range analyzed based on the measurement.

(Top coat layer 50)
The top coat layer 50 is coated with an acrylic two-component curable resin (acrylic urethane resin manufactured by DIC Graphic Corporation) so as to have a thickness of 6 μm.
On the surface of the top coat layer 50, an embossed portion 41 synchronized with the pattern of the printed pattern layer 30 is formed.

(Manufacturing method of decorative sheet 10)
The decorative sheet 10 has the above-mentioned configuration, and the manufacturing method thereof is as follows, as shown in FIG.
(1) First Step The first step is a step of sequentially forming a printed pattern layer 30 and a transparent polypropylene layer 40 on which a pattern is printed on the surface of the colored film layer 20.
Specifically, as the colored film layer 20, a colored polyethylene sheet containing a pigment (manufactured by RIKEN TECHNOS) having a predetermined thickness, for example, a thickness of 55 μm, is used.

A printed pattern layer 30 is formed on the surface of the colored film layer 20 by gravure printing, for example, using urethane ink (Lamister manufactured by Toyo Ink Mfg. Co., Ltd.).
A transparent polypropylene layer 40 (hereinafter, also referred to as “transparent PP layer 40”) is formed on the printed pattern layer 30 with, for example, a homopolypropylene resin (manufactured by Prime Polymer Co., Ltd.) to provide a predetermined thickness, for example, 70 μm. , Extrude and laminate to make a sheet with a flat surface.

(2) Second Step The second step is a step of irradiating the surface of the transparent polypropylene layer 40 with a laser beam 71 to form an embossed portion 41 having irregularities synchronized with the pattern of the printed pattern layer 30. Is.
The surface of the transparent PP layer 40 is irradiated with a laser beam 71, for example, a CO ² laser, to form, for example, a wood grain conduit-like unevenness as an embossed portion 41. At this time, it is necessary that the unevenness formed by the laser beam 71 does not exceed the thickness of the transparent polypropylene layer 40.

(3) Third Step The third step is a step of applying a corona treatment to the surface on which the embossed portion 41 is formed.
The surface of the transparent PP layer 40 having the unevenness formed on the embossed portion 41 is subjected to corona treatment.
(4) Fourth Step The fourth step is a step of applying a transparent resin to the corona-treated surface to form the top coat layer 50.
As the top coat layer 50, for example, an acrylic two-component curable resin (acrylic urethane resin manufactured by DIC Graphic Corporation) is applied so as to have a predetermined thickness, for example, a thickness of 6 μm.

(5) Fifth Step The fifth step is a step of forming a primer layer 60 on the back surface of the colored film layer 20.
The back surface of the colored film layer 20 is coated with, for example, a urethane resin and a primer layer 60 so that the solid content is, for example, 1 g / m ² by a gravure printing method, for example, to produce a decorative sheet 10. ..

(Example)
Hereinafter, Examples 1 and 1st Comparative Example 1 of the decorative sheet according to the present invention will be described with respect to the examples relating to the embossed portion 41.
The present invention is not limited to the following Example 1.

(Example 1)
In Example 1, the decorative sheet 10 was prepared by the following materials and procedures.
As the colored film layer 20, a pigment-blended colored polyethylene sheet (manufactured by RIKEN TECHNOS) having a thickness of 55 μm was used.
The surface of the colored film layer 20 was formed as a printed pattern layer 30 by gravure printing using urethane ink (Lamister manufactured by Toyo Ink Mfg. Co., Ltd.).
A homopolypropylene resin (manufactured by Prime Polymer Co., Ltd.) and 70 μm were extruded and laminated on the printed pattern layer 30 as a transparent PP layer 40 to prepare a sheet having a flat surface.
The surface of the transparent PP layer 40 was irradiated with a CO ² laser (laser light 71) to form an embossed portion 41 having a wood grain conduit-like unevenness.

The surface of the transparent PP layer 40 on which the embossed portion 41 was formed was subjected to corona treatment.
Further, as the top coat layer 50, an acrylic two-component curable resin (acrylic urethane resin manufactured by DIC Graphic Corporation) is applied so as to have a thickness of 6 μm.
Finally, the back surface of the colored film layer 20 is coated with a urethane resin so that the solid content is 1 g / m ² by a gravure printing method, and a primer layer 60 is applied to prepare an evaluation sheet of Example 1. did.

(Comparative Example 1)
Comparative Example 1 differs from Example 1 in that an embossed portion having irregularities is formed by using an embossed roll.
As the colored film layer, a pigment-blended colored polyethylene sheet (manufactured by RIKEN TECHNOS) having a thickness of 55 μm was used as in Example 1.
The surface of the colored film layer was formed as a printed pattern layer by gravure printing using urethane ink (Lamister manufactured by Toyo Ink Mfg. Co., Ltd.).
A homopolypropylene resin (manufactured by Prime Polymer Co., Ltd.), 70 μm, was extruded and laminated on the printed pattern layer as a transparent PP layer.

At that time, in order to reproduce the surface shape of the transparent PP layer, the embossed roll that reproduces the unevenness of the wood grain conduit is used at the time of extrusion laminating, and the surface is transparent with the embossed part that is the unevenness of the wood grain conduit. A PP layer was formed.
The surface of the transparent PP layer on which the embossed portion having irregularities was formed was subjected to corona treatment.
Further, as the top coat layer, an acrylic two-component curable resin (acrylic urethane resin manufactured by DIC Graphic Corporation) was applied so as to have a thickness of 6 μm.

Finally, the back surface of the colored film layer was coated with a urethane resin so that the solid content was 1 g / m ² by a gravure printing method, and a primer layer was applied to prepare an evaluation sheet of Comparative Example 1.

(Evaluation method and evaluation criteria)
The evaluation method of the evaluation sheet prepared above is as follows.
(1) Delicacy (2) Texture

(Delicacy)
In the delicacy test, the state of the embossed portion, which is the unevenness of the transparent PP layer, was visually observed and evaluated for each of the evaluation sheets.
The evaluation was made on a three-point scale of "◎", "○", and "×".
Delicate ones were marked as "◎" and passed.
Other than the above, that is, "○" and "×" were rejected.

(Texture)
In the texture test, the state of the embossed portion, which is the unevenness of the transparent PP layer, was visually observed and evaluated for each of the evaluation sheets.
The evaluation was made on a three-point scale of "◎", "○", and "×".
Those that reproduce the texture of real wood are marked with "◎" and passed.
Other than the above, that is, "○" and "×" were rejected.
(Evaluation results)
The evaluation results of the evaluation sheet are shown in Table 1 below.

(Example 1 and Comparative Example 1)
Of the two evaluation sheets of Example 1 and Comparative Example 1, only the evaluation sheet of Example 1 has a "◎" and "pass" in both delicacy and texture.
The remaining evaluation sheet of Comparative Example 1 was "○" in both delicacy and texture, and was "Failed".

It can be inferred that Comparative Example 1 was caused by the use of embossed rolls.
On the other hand, in Example 1, a more delicate uneven shape can be produced as compared with Comparative Example 1 in which an uneven shape is produced by embossing roll, and a decorative sheet that reproduces a more authentic texture is produced. I was able to.

10 Decorative sheet 20 Colored film layer 30 Printed pattern layer 40 Transparent polypropylene layer 41 Embossed part 42 Transparent skin layer 43 Transparent core layer 50 Top coat layer 60 Primer layer 70 Laser processing machine 71 Laser beam

Claims (3)

The first step of forming a printed pattern layer on which a pattern is printed and a transparent polypropylene layer on the surface of the colored film layer in order, and
A second step of irradiating the surface of the transparent polypropylene layer with a laser beam to form an embossed portion having irregularities synchronized with the pattern of the printed pattern layer.
A third step of applying a corona treatment to the surface on which the embossed portion is formed, and
A fourth step of applying a transparent resin to the corona-treated surface to form a top coat layer, and
A method for producing a decorative sheet, which comprises a fifth step of forming a primer layer on the back surface of the colored film layer. The method for manufacturing a decorative sheet according to claim 1, wherein the laser beam uses a CO ² laser. A printed pattern layer on which a pattern is printed and a transparent polypropylene layer are formed in order on the surface of the colored film layer.
A decorative sheet in which a primer layer is formed on the back surface of the colored film layer.
On the surface of the transparent polypropylene layer,
An embossed portion formed by irradiating a laser beam with an embossed portion synchronized with the pattern of the printed pattern layer.
A corona-treated portion in which the surface having the embossed portion is subjected to corona treatment, and a corona-treated portion.
A decorative sheet comprising a top coat layer coated with a transparent resin on the surface having the corona-treated portion.

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