JP2020185774A - Colored sheet, decorative sheet and manufacturing method thereof - Google Patents

Abstract

To provide a colored sheet with improved scratch resistance while suppressing a stretch at print processing, and capable of reducing an occurrence of flexure whitening or crack, and also to provide a decorative sheet having the colored sheet, and a manufacturing method of the decorative sheet.SOLUTION: A decorative sheet 1 includes: a colored layer 3 containing an inorganic pigment and a polypropylene resin; and a skin layer 4 containing a polypropylene resin. The skin layer 4 is formed through adding a nano-sized nucleating agent.SELECTED DRAWING: Figure 1

Description

The present invention relates to a colored sheet, a decorative sheet, and a method for producing the same. In particular, it is a technique suitable for decorative sheets used for building materials for exteriors and interiors of buildings, surfaces of fittings, surface materials of home appliances, and the like.

In recent years, as shown in Patent Document 1, many decorative sheets using olefin resins (for example, polypropylene sheets) have been proposed as decorative sheets to replace polyvinyl chloride decorative sheets, which are concerned about environmental protection problems. ing. By not using vinyl chloride resin in these decorative sheets, the generation of toxic gas and the like during incineration is suppressed. However, in general, polypropylene sheets have problems such as poor scratch resistance due to their low elastic modulus and easy elongation when tension is applied to the sheets during sheet production such as printing.

By the way, a decorative sheet is attached to the surface of a substrate such as a wood substrate, a metal substrate, or a non-combustible substrate to form a decorative board, and the decorative sheet imparts a design property to the decorative board according to the purpose. Therefore, the decorative sheet needs to cover the base material so that the surface of the substrate is completely invisible, if necessary. In this case, it is necessary to use a decorative sheet that is at least colored with a pigment and has a concealing property. The simplest configuration of the decorative sheet is a composition of only a base material layer composed of a single colored sheet (single layer). In the case of a decorative sheet consisting of only such a base material layer, the design that can be applied is usually limited to a single color without a pattern, but for example, by adding a bright material such as aluminum flakes or pearl pigment as a pigment, it shines. Since it is possible to give a feeling, it is possible to express the necessary and sufficient design. Further, when it is desired to give a higher design, it is also effective to decorate the surface of the base material layer by printing or the like.

On the other hand, as described above, since the colored polypropylene film has a low elastic modulus, when it is used as a single-layer decorative sheet, it is necessary to have scratch resistance and prevent it from stretching even when tension is applied during processing such as printing. The elongation at the time of applying tension can be improved by increasing the layer thickness to about 50 μm or more in the conventional colored polypropylene film. Regarding the scratch resistance, in the conventional colored polypropylene film, a transparent resin layer made of polypropylene resin or a urethane-based thermosetting resin made of polyol and isocyanate was used as in Patent Documents 2 and 3. Improvement is possible by providing a top coat layer.

Further, as in Patent Document 2 and Patent Document 3, by optimally selecting the polypropylene resin used for the colored polypropylene film, it is possible to improve the scratch resistance and the elongation during printing processing. However, while the elastic modulus is improved by increasing the crystallinity, the breaking stress does not increase correspondingly to the elastic modulus, so that the film itself is easily torn, and defects such as breaking are likely to occur during printing. There is. Further, in post-processing as a decorative sheet, particularly during bending processing such as V-cutting, defects such as cracking and whitening of the bent portion tend to occur easily.

Japanese Patent No. 3271022 Japanese Patent No. 3861472 Japanese Patent No. 3772634

Conventionally, a decorative sheet using a colored polypropylene film alone or a decorative sheet using a colored polypropylene film as a base material has both print processing suitability (difficulty in stretching, etc.), scratch resistance, and bending workability. Is required.
The present invention has been made by paying attention to the above points, and is a colored sheet capable of improving scratch resistance, suppressing elongation during printing, and reducing bending whitening and cracking. An object of the present invention is to provide a decorative sheet provided with a colored sheet and a method for producing the decorative sheet.

The present inventors enclose a nucleating agent for improving the crystallinity of polypropylene in a vesicle having an outer film of a monolayer film, vesicle it, and add it to the skin layer as a nucleating agent vesicle, and further. By repeating various studies and experiments on the manufacturing process and setting the crystallinity within the optimum range, it was found that a colored sheet, a decorative sheet and a method for manufacturing the same can be provided in which the above problems are improved.

In order to achieve the object, the coloring sheet according to one aspect of the present invention has a coloring layer containing an inorganic pigment and a polypropylene resin, and a skin layer containing a polypropylene resin, and the skin layer is a nano-sized nucleating agent. The gist is that it was formed by adding.
In one aspect of the present invention, the skin layer means a transparent layer containing no pigment, and may contain additives such as a nucleating agent and a weather resistant agent. Further, in the colored sheet according to one aspect of the present invention, the nucleating agent may be contained in the state of a vesicle of the nucleating agent contained in the outer film.
Here, the nucleating agent vesicle has a structure in which the nucleating agent is encapsulated in a capsule-shaped vesicle having an outer membrane of a monolayer film, and can be prepared by, for example, a supercritical reverse phase evaporation method. .. The nucleating agent is a substance that is a starting point of crystallization in a crystalline polypropylene resin.

According to one aspect of the present invention, by adding a nucleating agent that improves the crystallinity of polypropylene to the skin layer as a vesicle of the nucleating agent, for example, print processing suitability (difficulty in elongation, etc.). It is possible to provide a colored sheet capable of having scratch resistance and bendability, a decorative sheet containing the colored sheet, and a method for producing the decorative sheet.

It is sectional drawing which shows the structure of the decorative sheet of embodiment which concerns on this invention. It is sectional drawing which shows the structure of the other decorative sheet which concerns on embodiment based on this invention. It is sectional drawing which shows the structure of the decorative sheet which concerns on Example based on this invention.

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

"Constitution"
The decorative sheet 1 of the embodiment shown in FIG. 1 is an example in the case of a single-layer structure of only the colored sheet 2. The colored sheet 2 of the present embodiment is composed of a colored layer 3 formed by mixing an inorganic pigment with a polypropylene resin, that is, a colored layer 3 containing the inorganic pigment and the polypropylene resin, and a skin layer 4 containing the polypropylene resin. A nano-sized nucleating agent is added to the skin layer 4 in order to improve the crystallinity. By improving the crystallinity, the scratch resistance is improved. In the present embodiment, the nucleating agent may be contained, for example, in the form of a vesicle of the nucleating agent contained in the outer membrane.

The thickness of the skin layer 4 is within the range of 3 μm or more and 20 μm or less, or the ratio of the thickness of the skin layer 4 to the colored layer 3 (thickness of the skin layer 4 / thickness of the colored layer 3) is 1. : It is desirable that it is in the range of 6 to 1:50. If the skin layer 4 is thinner than the above value and the ratio to the colored layer 3 is small, it is difficult to obtain the effect of improving the crystallinity, which is not preferable. Further, if the ratio of the skin layer 4 to the colored layer 3 becomes small, the pigment added to the colored layer 3 may bleed out, which is not preferable. On the other hand, if the skin layer 4 is thicker than the above numerical value and the ratio to the colored layer 3 is large, the ratio of the colored layer 3 is lowered and the hiding property is lowered, which is not preferable.

Further, it is more desirable that the ratio of the thickness of the skin layer 4 to the colored layer 3 (thickness of the skin layer 4 / thickness of the colored layer 3) is in the range of 1:10 to 1:30. When the ratio of the thickness of the skin layer 4 to the colored layer 3 is within the above numerical range, it is possible to improve the crystallinity and prevent the hiding property from being lowered.
Further, with respect to the colored layer 3 and the skin layer 4, the peak intensities x _c and x _s calculated from the absorption spectra obtained by the Fourier infrared spectroscopic measurement may be expressed by the relational expression x _c <x _s. .. In such a case, the skin layer 4 located on the surface side (outside) of the colored sheet 2 has a higher crystallinity than the colored layer 3 located inside the colored sheet 2, and the scratch resistance is improved. Tend to do. On the other hand, since the colored layer 3 has a lower crystallinity and is more flexible than the skin layer 4, there is a tendency that problems such as cracking and whitening of the bent portion are less likely to occur during bending such as V-cutting.

The amount of the nano-sized nucleating agent added is preferably in the range of 0.01 parts by mass or more and 0.5 parts by mass or less with respect to 100 parts by mass of the polypropylene resin.
When the nucleating agent vesicle is used, the amount of the nucleating agent vesicle added is 0.01 part by mass or more in terms of the nucleating agent in the nucleating agent vesicle with respect to 100 parts by mass of the polypropylene resin. It is preferably in the range of 5 parts by mass or less.
Further, the nucleating agent vesicle is preferably a nucleating agent liposome having an outer membrane made of a phospholipid.

Further, if necessary, as shown in FIG. 2, the pattern layer 5 may be formed (laminated) on one surface of the colored sheet 2 to improve the design. Further, in the decorative sheet 1, at least one layer of the transparent resin layer 6 and the top coat layer 7 may be laminated on one surface side of the colored film 2. The decorative sheet 1 illustrated in FIG. 2 is an example in which the pattern layer 5, the transparent resin layer 6, and the top coat layer 7 are laminated in this order on one surface of the colored sheet 2. In addition, one of the transparent resin layer 6 and the top coat layer 7 may be omitted. Further, the pattern layer 5 may be omitted.

Here, at least one of the transparent resin layer 6 and the top coat layer 7 may be provided with an embossed uneven pattern (embossed pattern 6a) depending on the requirements for design. It is also possible to embed ink in the embossed pattern 6a to further improve the design. Further, if there is a problem in the adhesion between the pattern layer 5 and the transparent resin layer 6, an adhesive resin layer 6b for improving the adhesion between the pattern layer 5 and the transparent resin layer 6 may be appropriately provided. When the adhesive resin layer 6b is provided, it may be formed by a coextrusion method of the transparent resin layer 6 and the adhesive resin layer 6b. The adhesive resin layer 6b may be, for example, an acid-modified resin such as polypropylene, polyethylene, or acrylic, that is, an acid-modified resin. The thickness of the adhesive resin layer 6b is preferably 2 μm or more for the purpose of improving the adhesive strength. Further, from the requirements of scratch resistance and the like, it is possible to laminate at least one of the transparent resin layer 6 and the top coat layer 7 in a plurality of layers. The decorative sheet 1 of the present embodiment may be configured to arrange other known layers.

In FIGS. 1, 2 and 3 described later, reference numeral B represents a substrate. The substrate B is a substrate to which the decorative sheet 1 is attached. The substrate B is not particularly limited, and examples thereof include wood boards, inorganic boards, metal plates, and composite boards made of a plurality of materials. A primer layer 8 or a concealing layer (not shown) may be appropriately provided between the decorative sheet 1 and the substrate B.
The tensile elastic modulus of the decorative sheet 1 of the present embodiment, particularly the tensile elastic modulus of the colored film 2 alone, is preferably in the range of 1000 MPa or more and 2200 MPa or less. When the tensile elastic modulus is less than 1000 MPa, the scratch resistance tends to deteriorate. Further, when the tensile elastic modulus exceeds 2200 MPa, the crystallinity is too high, and even when a nucleating agent (for example, a nucleating agent vesicle) is used, problems such as whitening and cracking may occur in the bending process. ..

Next, each layer constituting the decorative sheet 1 will be described.
<Colored sheet (colored film) 2>
The colored sheet 2 has, for example, a colored layer 3 formed by mixing an inorganic pigment with a polypropylene resin and a skin layer 4 made of a polypropylene resin, and the skin layer 4 has a nano-sized structure in order to increase crystallinity. A nuclear agent has been added. In this embodiment, a nano-sized nucleating agent is added in the form of a nucleating agent vesicle. The thickness of the skin layer 4 is preferably in the range of 3 μm or more and 20 μm or less, and the ratio of the thickness of the skin layer 4 to the colored layer 3 (thickness of the skin layer 4 / thickness of the colored layer 3) is 1: 6 to 1. : It is desirable that it is in the range of 50.

Further, if the purpose is to improve the scratch resistance of the surface, the skin layer 4 may be formed only on the upper surface of the colored layer 3, but when the skin layer 4 is formed by the coextrusion method, if the colored layer 3 is on the outermost layer, the colored layer 3 may be formed. The pigment component contained in the extruder may bleed and contaminate the T-die of the extruder and the roll during transportation. Therefore, it is desirable that the outermost layer is a skin layer 4 containing no pigment. Further, it is more desirable to provide the skin layers 4 on both sides of the colored layer 3. That is, it is more preferable that the skin layer 4, the colored layer 3, and the skin layer 4 are provided in this order, and the thickness ratio of each layer is within the range of 1: 6: 1 to 1:50: 1. If the skin layer 4 is thinner than the above value and the ratio to the colored layer 3 is small, it is difficult to obtain the effect of improving the crystallinity, which is not preferable. Further, if the ratio of the skin layer 4 to the colored layer 3 becomes small, the pigment added to the colored layer 3 may bleed out, which is not preferable. On the other hand, if the skin layer 4 is thicker than the above numerical value and the ratio to the colored layer 3 is large, the ratio of the colored layer 3 is lowered and the hiding property is lowered, which is not preferable.

Further, the ratio of the thickness of the skin layer 4, the colored layer 3, and the skin layer 4 (thickness of the skin layer 4 / thickness of the colored layer 3 / thickness of the skin layer 4) is from 1:10: 1 to 1: 1. More preferably, it is in the range of 30: 1. When the ratio of the thickness of the skin layer 4, the colored layer 3, and the skin layer 4 is within the above numerical range, it is possible to improve the crystallinity and prevent the hiding property from being lowered.
The thickness of the outermost skin layer 4 and the skin layer 4 on the substrate B side may be different from each other. That is, the thickness of the outermost skin layer 4 may be thicker or thinner than the thickness of the skin layer 4 on the substrate B side. When the thickness of the outermost skin layer 4 is thicker than the thickness of the skin layer 4 on the substrate B side, the scratch resistance of the surface is improved. Further, when the thickness of the outermost skin layer 4 is thinner than the thickness of the skin layer 4 on the substrate B side, the cushioning property (buffering performance) of the surface is improved.

In the present embodiment, the peak intensity ratios x _c and x _s calculated from the absorption spectra obtained by the Fourier infrared spectroscopic measurement of the colored layer 3 and the skin layer 4 are within the range of 0.7 or more and 0.9 or less. You may adjust. When the peak intensity ratios x _c and x _s are less than 0.7, it is likely that defects during printing processing cannot be suppressed and it becomes difficult to secure practically necessary scratch resistance. On the other hand, when the peak intensity ratio x exceeds 0.9, the crystallinity is too high, and even when the nucleating agent vesicle is used, problems such as whitening and cracking may occur in the bending process. Further, even if the colored film 2 is produced under the same manufacturing conditions as the colored layer 3 by the coextrusion method by adding the nanonucleating agent to the skin layer 4, the peak intensity ratios x _c and x _s are x _c <. It can be expressed by the formula of x _s . When the above relational expression is satisfied, the skin layers 4 at both ends are harder and the colored layer 3 of the core is softer, so that the colored film 2 is less likely to cause problems such as whitening and cracking in the bending process.

Here, the Fourier type infrared spectroscopic measurement will be described. First, infrared spectroscopic measurement is the principle that the amount of infrared light, which is light having a wavelength of 2.5 to 25 μm, is absorbed by the substance based on the vibration and rotational motion of the molecule of the substance. This is a measurement method for obtaining information on the chemical structure and state of a substance by measuring the infrared light absorbed by the substance. The specific measurement method is to irradiate a substance with infrared light from a light source, generate an interference wave by synthesizing the divided transmitted light and reflected light, and calculate the number of each wave from the signal intensity of the interference wave. The infrared spectrum is measured by calculating the light intensity of the component. In particular, in the present embodiment, the interference wave is calculated by using the Fourier transform method, and the measurement is performed by Fourier-type infrared spectroscopic measurement, which is a method for measuring the infrared spectrum. A graph in which the wave number obtained by the above method is plotted on the horizontal axis and the measured absorbance (or transmittance) is plotted on the vertical axis is called an infrared absorption spectrum (or infrared transmission spectrum), and a unique pattern is recognized for each substance. Be done. At this time, the absorbance on the vertical axis changes in proportion to the concentration and thickness of the substance, and in the case of a crystalline substance, the amount of the crystalline or amorphous part, so that the value of the peak intensity at a predetermined wave frequency changes. It is also possible to perform quantitative analysis from the height and area of the peak.

In the present embodiment, by utilizing the above-mentioned characteristics of the infrared absorption spectrum, the peak intensity of a wave number of 997 cm ^-1 corresponding to the absorbance of the crystalline part of the colored polypropylene film in the absorption spectrum obtained by the above measurement is used. And the ratio to the peak intensity of the wave number 973 cm ^-1 corresponding to the absorbance of the amorphous part of the film, that is, the peak intensity ratio x representing the crystallinity of polypropylene was calculated using the following formula, and the colored layer 3 and The relationship between the peak intensity ratios x _c and x _{s of the} skin layer 4 and the rigidity of the colored polypropylene film was clarified, and a colored polypropylene film having a peak intensity ratio x within a predetermined range was used as the base material layer for cosmetics having excellent rigidity. Sheet 1 is provided. The peak intensity of wave number 997 cm ^{-1 and} the peak intensity of wave number 973 cm ^-1 are background-corrected using the peak intensity of wave number 938 cm ^-1 .

Further, it is important that the thickness of the colored film 2 is within the range of 50 μm or more and 150 μm or less. When the colored film 2 is less than 50 μm, the performance (non-landing property) of covering the unevenness of the base is poor, which is not preferable. Even if the elastic modulus is further improved, the film strength is insufficient, so that it is difficult to suppress defects during printing processing and deterioration of scratch resistance. On the other hand, if the thickness of the colored film 2 exceeds 150 μm, problems such as whitening and cracking may occur in the bending process.

(Polypropylene resin)
The polypropylene resin used for the colored layer 3 is preferably mixed with a random polypropylene resin having ethylene content or a known amorphous polypropylene resin within a predetermined range in order to facilitate dispersion of an inorganic pigment described later. Highly crystalline homopolypropylene can be used in applications where the elastic modulus is improved and scratch resistance is important, but the elastic modulus can also be adjusted by using a plurality of polypropylene resins in combination. In addition, the elastic modulus can be controlled by a manufacturing method.

As the polypropylene resin used for the skin layer 4, it is preferable to use a homopolypropylene resin having high crystallinity. The polypropylene resin may be used alone or in combination.
The crystallization temperature of the polypropylene resin is generally in the range of 100 to 130 ° C., and when a nucleating agent is added, it is in the range of 110 to 140 ° C. In the manufacturing process of the colored film 2 in the decorative sheet 1 of the present embodiment, the cooling time from the crystallization temperature to the curing completion temperature within this range is controlled by a known cooling process to obtain the colored layer 3 and the colored layer 3. The values of the peak intensities x _c and x _s of the skin layer 4 are adjusted within the range of 0.7 or more and 0.9 or less. Further, by adding a nucleating agent or selecting a suitable polypropylene resin for the skin layer 4, the peak intensities x _c and x _s of the colored layer 3 and the skin layer 4 are set to x _c <x _s. I'm adjusting.

(Inorganic pigment)
As the inorganic pigment, a known inorganic pigment typified by titanium oxide for imparting hiding property can be used. The colored film 2 plays a role of concealing the pattern of the base material B. In order to obtain the hiding property required from the viewpoint of the design of the decorative sheet 1, the light transmittance is preferably 40% or less. If the hiding property is low, the patterns of the pattern layer 5 and the base material B are mixed, which is not preferable. By containing an inorganic pigment, it is possible to obtain a decorative sheet 1 having a good hiding property. The mixing amount of the inorganic pigment is preferably in the range of 5 parts by mass or more and 50 parts by mass or less with the resin material as 100 parts by mass. If the mixing amount is small (less than 5 parts by mass), the hiding property is poor, and if the mixing amount is 50 parts by mass or more, embrittlement of the colored film 2 occurs, which is not preferable. The inorganic pigment contained is not particularly limited, and examples thereof include natural inorganic pigments and synthetic inorganic pigments. Examples of natural inorganic pigments include earth-based pigments, calcined soil, and mineral pigments. Examples of synthetic inorganic pigments include oxide pigments, hydroxide pigments, sulfide pigments, silicate pigments, phosphate pigments, carbonate pigments, metal powder pigments, carbon pigments and the like. Further, a mixed pigment obtained by mixing one or more of natural inorganic pigments and synthetic inorganic pigments may be used. An organic pigment such as carbon black may be used in combination.
Further, an additive such as a fatty acid metal salt may be added in order to improve the dispersibility and the extrusion suitability.

(Nucleating agent vesicle)
Further, the skin layer 4 of the colored film 2 contains a nano-sized nucleating agent. The nano-sized nucleating agent may be 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 monolayer film. Since the skin layer 4 of the colored film 2 contains a nucleating agent, the crystallinity can be improved, and the scratch resistance (scratch resistance) of the colored film 2 can be improved. In the present embodiment, the nucleating agent in the resin constituting the skin layer 4 of the colored film 2 may be included in the vesicle with a part of the nucleating agent exposed.

The average particle size of the nano-sized nucleating agent is preferably 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 polypropylene resin, the end where the crystal is growing is immediately located. It comes into contact with the ends of crystals growing from the surface of another nucleating agent particle adjacent to one nucleating agent particle, and the ends of each crystal inhibit the growth and the growth of each crystal is stopped. Therefore, the average particle size of spherulite in the crystal portion of the crystalline polypropylene resin can be reduced, for example, the spherulite size can be reduced to 1 μm or less. As a result, the colored film 2 having a high degree of crystallinity and high hardness can be obtained, and the stress concentration between the spherulites generated during the bending process is efficiently dispersed, so that cracking and whitening during the bending process are suppressed. The colored film 2 can be realized.

Here, when the nucleating agent is simply added, the number of crystal nuclei increases with respect to the amount of the nucleating agent added as the particle size increases due to the secondary agglutination of the nucleating agent in the polypropylene resin. It will be significantly less than when added as an agent vesicle. For this reason, the average particle size of the spherulites in the crystal portion of the polypropylene resin becomes large, and cracking and whitening during bending may not be suppressed. Therefore, it may not be possible to achieve both improvement in elastic modulus and workability by increasing the crystallinity.

The skin layer 4 of the colored film 2 constituting the decorative sheet 1 of the present embodiment is 0.01 part by mass or more and 0.5 parts by mass or more in terms of the amount of nucleating agent added to 100 parts by mass of polypropylene resin as a main component. The nucleating agent vesicle is added in the range of parts by mass or less, preferably 0.05 parts by mass or more and 0.3 parts by mass or less. If the amount of the nucleating agent vesicle added is less than 0.01 parts by mass, the crystallinity may not be sufficiently improved and the required elastic modulus (hardness) may not be reached. Further, when the amount of the nucleating agent vesicle added exceeds 0.5 parts by mass, the spherulite growth is conversely inhibited due to the excess of crystal nuclei, and as a result, the crystallinity is not sufficiently improved and the required elasticity is required. The rate (hardness) may not be reached.

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 vapor phase method for synthesizing and crystallizing nano-sized particles from gas / vapor 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.

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 capsules (nano-sized vesicles) containing a target substance using carbon dioxide in a supercritical state or under temperature conditions or pressure conditions above the critical point. The carbon dioxide in the 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 above the critical point. Carbon dioxide under pressure conditions means carbon dioxide under conditions where only temperature or pressure exceeds critical conditions.

In addition, as a specific nano-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 inclusion substance. Then, by stirring, an emulsion of supercritical carbon dioxide and an aqueous phase is formed. 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 produced. Small diameter capsules can be prepared.

The nucleating agent vesicle can be prepared by, for example, the Bangham method, the extrusion method, the hydration method, the surfactant dialysis method, the reverse phase evaporation method, the freeze-thaw method, the supercritical reverse phase evaporation method, or the like. Among them, the supercritical reverse phase evaporation method is particularly preferable.
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 biolipid such as a phospholipid is referred to as a nucleating agent liposome.

Examples of the phospholipids constituting the outer membrane include phosphatidylcholine, phosphatidylethanolamine, phosphatidylceramide, phosphatidic acid, phosphatidylglycerol, phosphatidylinositol, cardiopine, yellow egg lecithin, hydrogenated yellow egg lecithin, soybean lecithin, hydrogenated soybean lecithin and the like. Examples of sphingolin phospholipids such as glycerophospholipids, sphingomyelin, ceramide phosphorylethanolamine, and ceramide phosphorylglycerol.

Other substances that form the outer membrane of the vesicle include, for example, nonionic surfactants and dispersants such as a mixture thereof with cholesterol or triacylglycerol. 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 copolymer. , Polybutadiene-polyoxyethylene copolymer, polybutadiene-poly2-vinylpyridine, polystyrene-polyacrylic acid copolymer, polyethylene oxide-polyethylethylene copolymer, polyoxyethylene-polycaprolactam copolymer, etc. Alternatively, two or more types 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 1 of the present embodiment, the nucleating agent vesicle is preferably a radical scavenger liposome having an outer membrane made of phospholipid, and by forming the outer membrane made of phospholipid, the skin layer 4 is formed. 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 phosphoric acid ester metal salt, benzoic acid metal salt, piperinate metal salt, rosin metal salt, benziliden sorbitol, quinacridone, cyanine blue and talc. In particular, in order to maximize the effect of the nano-treatment, it is preferable to use a phosphoric acid ester metal salt, a benzoic acid metal salt, a pimelli 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.

As described above, one of the features (invention-specific matters) of the decorative sheet 1 of the present embodiment is that "the skin layer 4 of the colored film 2 contains a nucleating agent contained in the vesicle". Then, by adding the nucleating agent to the resin composition in a state of being encapsulated in the vesicle, the dispersibility of the nucleating agent in the resin material, that is, in the skin layer 4 of the colored film 2 is dramatically improved. Although it is effective, it is impractical to directly identify its characteristics by the structure and characteristics of the finished decorative sheet 1 in some situations. 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 produced decorative sheet 1, the nucleating agent is applied to the skin layer 4 of the colored film 2. Highly dispersed. However, in the process of producing the decorative sheet 1 after the skin layer 4 of the colored film 2 is produced by adding a nucleating agent in the form of a vesicle to the resin composition constituting the skin layer 4 of the colored film 2, it is usually used. , Various treatments such as compression treatment and hardening treatment are performed on the laminate, and by such treatment, the outer film of the vesicle containing the nucleating agent is crushed or chemically reacted, and the nucleating agent is removed. It may not be included (foreskin) by the film. This is because the state in which the outer film is crushed or chemically reacted varies depending on the treatment process of the decorative sheet 1. In situations where this nucleating agent is not included in the outer membrane, it is difficult to specify the physical properties themselves in the numerical range, and is the constituent material of the crushed outer membrane the outer membrane of the vesicle? It may be difficult to determine whether the material is added separately from the nucleating agent. As described above, the present invention is different from the conventional one in that the nucleating agent is blended with the skin layer 4 of the colored film 2 in a high dispersion, but the vesicle containing the nucleating agent is contained. In the state of the decorative sheet 1, it is assumed that it is impractical to specify the structure and characteristics of the decorative sheet 1 within the numerical range analyzed based on the measurement, whether or not it was added in the state.
Here, the nucleating agent vesicle having the above structure may also be contained in the transparent resin layer 6 and the top coat layer 7.

(Pattern layer 5)
A pattern layer 5 for adding a pattern to the decorative sheet 1 can be provided on the surface of the colored film 2. As the pattern, for example, a wood grain pattern, a stone grain pattern, a sand grain pattern, a tiled pattern, a brickwork pattern, a cloth grain pattern, a leather squeezing pattern, a geometric figure, or the like can be used.
When a base material having an inert surface such as an olefin-based raw fabric layer is used as the colored film 2, for example, corona treatment, plasma treatment, ozone treatment, electron beam treatment, ultraviolet treatment, etc. are used on the front and back surfaces of the colored film 2. It is desirable to perform treatment with heavy chromium acid.

Further, a solid base ink layer (not shown) may be provided between the colored film 2 and the pattern layer 5 according to the degree of the target design. The base solid ink layer is provided so as to cover the entire surface of the colored film 2. Further, the base solid ink layer may have two or more layers, if necessary, such as hiding property. Further, the pattern layer 5 may be formed by laminating as many plates as necessary to express the required design. As described above, the pattern layer 5 and the base solid ink layer have various combinations depending on the required design, that is, the design to be expressed, but are not particularly limited.

The constituent materials of the base solid ink layer and the pattern layer 5 are not particularly limited. For example, a printing ink or coating agent obtained by dissolving and dispersing a matrix and a colorant such as a dye or a pigment in a solvent can be used. Examples of the matrix include oil-based vitrified cotton resin, two-component urethane resin, acrylic resin, styrene resin, polyester resin, urethane resin, polyvinyl resin, alkyd resin, epoxy resin, melamine resin, and fluorine resin. Various synthetic resins such as resins, silicone resins, and rubber resins, or mixtures thereof, copolymers, and the like can be used. Examples of colorants include inorganic pigments such as carbon black, titanium white, zinc oxide, petals, chrome yellow, navy blue, and cadmium red, azo pigments, lake pigments, anthraquinone pigments, phthalocyanine pigments, and isoindolinone pigments. , Organic pigments such as dioxazine pigments, or mixtures thereof. As the solvent, for example, toluene, xylene, ethyl acetate, butyl acetate, methyl alcohol, ethyl alcohol, isopropyl alcohol, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, water and the like, or a mixture thereof can be used. ..

Further, in order to impart various functions to the base solid ink layer and the pattern layer 5, for example, an extender pigment, a plasticizer, a dispersant, a surfactant, a tackifier, an adhesive aid, a desiccant, a curing agent, and curing Functional additives such as accelerators and curing retarders may be added.
Here, the base solid ink layer and the pattern layer 5 can be formed by various printing methods such as a gravure printing method, an offset printing method, a screen printing method, an electrostatic printing method, and an inkjet printing method. Further, since the base solid ink layer covers the entire surface of the colored film 2, it can be formed by various coating methods such as a roll coating method, a knife coating method, a microgravure coating method, and a die coating method. These printing methods and coating methods may be selected separately depending on the layer to be formed, but it is efficient to select the same method and perform batch processing.
The thickness of the pattern layer 5 is preferably in the range of 3 μm or more and 20 μm or less. When the thickness of the pattern layer 5 is within this numerical range, printing can be clarified, printing workability when manufacturing the decorative sheet 1 can be improved, and manufacturing cost can be suppressed.

(Transparent resin layer 6)
The resin material used as the main component of the transparent resin layer 6 is preferably made of an olefin resin. For example, in addition to polypropylene, polyethylene, polybutene and the like, α-olefin (for example, propylene, 1-butene and 1-pentene) , 1-hexene, 1-heptene, 1-octene, 1-nonen, 1-decene, 1-ethylene, 1-dodecene, tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene , 1-Nonadecene, 1-Eicosen, 3-Methyl-1-butene, 3-Methyl-1-pentene, 3-Ethylene-1-Pentene, 4-Methyl-1-Pentene, 4-Methyl-1-hexene, 4 , 4-Dimethyl-1-pentene, 4-ethyl-1-hexene, 3-ethyl-1-hexene, 9-methyl-1-decene, 11-methyl-1-dodecene, 12-ethyl-1-tetradecene, etc.) Is homopolymerized or copolymerized with two or more types, ethylene / vinyl acetate copolymer, ethylene / vinyl alcohol copolymer, ethylene / methyl methacrylate copolymer, ethylene / ethyl methacrylate copolymer, ethylene / butyl. Copolymerization of ethylene or α-olefin with other monomers, such as methacrylate copolymer, ethylene / methyl acrylate copolymer, ethylene / ethyl acrylate copolymer, ethylene / butyl acrylate copolymer, etc. Can be mentioned. Further, in order to improve the surface strength of the decorative sheet 1, it is preferable to use highly crystalline polypropylene.

Here, the main component in the present specification refers to 90% by mass or more of the target material, unless otherwise specified.
When the transparent resin layer 6 is provided, the layer thickness of the transparent resin layer 6 is preferably in the range of 50 μm or more and 100 μm or less. When the layer thickness of the transparent resin layer 6 is less than 50 μm, the effect of improving the scratch resistance on the surface of the transparent resin layer 6 is low, and the significance of providing the transparent resin layer 6 is reduced. Further, when the layer thickness of the transparent resin layer 6 exceeds 100 μm, the rigidity of the decorative sheet 1 is too high, and there is a possibility that problems such as whitening and cracking may occur in the bending process.

However, when the top coat layer 7 is provided on the transparent resin layer 6, the layer thickness of the transparent resin layer 6 may be less than 50 μm.
The resin composition constituting the transparent resin layer 6 has various functionalities such as a heat stabilizer, a light stabilizer, an antiblocking agent, a catalyst scavenger, a colorant, a light scattering agent, and a gloss adjusting agent, if necessary. Additives may be included. These various functional additives can be appropriately selected and used from well-known ones.

Further, the adhesive used to bring the pattern layer 5 and the transparent resin layer 6 into close contact with each other can be selected from any material, for example, acrylic, polyester, polyurethane or the like. Usually, a two-component curing type urethane-based material utilizing the reaction between isocyanate and polyol is desirable because of its cohesive force. The method of laminating the pattern layer 5 and the transparent resin layer 6 is not particularly limited, but a method applying heat pressure (heat laminating), an extrusion laminating method, a dry laminating method, or the like is common. Further, when embossing the pattern 6a, there are a method of later embossing the sheet once laminated by various methods by heat pressure, and a method of providing an uneven pattern on the cooling roll and embossing at the same time as extrusion laminating.

Further, a method of laminating the embossed pattern layer 5 and the transparent resin layer 6 at the same time as extrusion by heat laminating or dry laminating can be used.
Further, when further laminating strength is required by the extrusion laminating method, an adhesive resin layer 6b may be provided between the transparent resin layer 6 and the adhesive. When the adhesive resin layer 6b is provided, the transparent resin layer 6 and the adhesive resin layer 6b are laminated by a coextrusion method. The adhesive resin layer 6b may be, for example, an acid-modified resin such as polypropylene, polyethylene, or acrylic, that is, an acid-modified resin. The thickness of the adhesive resin layer 6b is preferably 2 μm or more for the purpose of improving the adhesive strength.

(Top coat layer 7)
When it is necessary to further improve the scratch resistance and adjust the gloss, the top coat layer 7 can be provided on the surface of the transparent resin layer 6.
The resin material as the main component of the top coat layer 7 is appropriately selected from, for example, polyurethane-based, acrylic silicon-based, fluorine-based, epoxy-based, vinyl-based, polyester-based, melamine-based, aminoalkyd-based, and urea-based resin materials. Can be used. The form of the resin material is not particularly limited, such as water-based, emulsion, and solvent-based. As for the curing method, a one-component type, a two-component type, an ultraviolet curing method, or the like can be appropriately selected.

As the resin material used as the main component of the topcoat layer 7, a urethane-based resin material using isocyanate is suitable from the viewpoints of workability, price, and cohesive force of the resin itself. Examples of isocyanates include tolylene diisocyanate (TDI), xylylene diisocyanate (XDI), hexamethylene diisocyanate (HMDI), diphenylmethane diisocyanate (MDI), lysine diisocyanate (LDI), isophorone diisocyanate (IPDI), and bis (isocyanate methyl). It can be appropriately selected from curing agents such as adduct, buretto, and isocyanurate, which are derivatives such as cyclohexane (HXDI) and trimethylhexamethylene diisocyanate (TMDI), but it is linear in consideration of weather resistance. Hexamethylene diisocyanate (HMDI) or isophorone diisocyanate (IPDI) -based curing agent having the above molecular structure is suitable. In addition to this, when improving the surface hardness, it is preferable to use a resin that is cured by active energy rays such as ultraviolet rays and electron beams. These resins can be used in combination with each other. For example, by using a hybrid type of a thermosetting type and a photocuring type, the surface hardness can be improved, the curing shrinkage can be suppressed, and the adhesion can be improved. Can be planned.

A gloss adjuster can be added to the top coat layer 7 for gloss adjustment. As the gloss adjusting agent, a known commercially available product may be used. For example, fine particles made of an inorganic material such as silica, glass, alumina, calcium carbonate, and barium sulfate may be used. Alternatively, fine particles made of an organic material such as acrylic can be used. However, when high transparency is required, it is desirable to use fine particles such as silica, glass, and acrylic having high transparency. In particular, among the fine particles such as silica and glass, a gloss adjuster having a low bulk density in which fine primary particles are secondarily agglutinated instead of solid subatomic particles has a high matting effect on the amount of addition. Therefore, by using such a gloss adjusting agent, the amount of the gloss adjusting agent added can be reduced.

Further, in order to impart various functions to the top coat layer 7, functional additives such as an antibacterial agent and an antifungal agent may be added. Further, an ultraviolet absorber and a light stabilizer may be added as needed. As the ultraviolet absorber, for example, benzotriazole-based, benzoate-based, benzophenone-based, triazine-based, and cyanoacrylate-based can be used. Further, as the light stabilizer, a hindered amine type can be used.
The layer thickness of the top coat layer 7 is preferably in the range of 3 μm or more and 15 μm or less. When the layer thickness of the top coat layer 7 is less than 3 μm, the effect of improving the scratch resistance is low, and the significance of providing the top coat layer 7 may be reduced. Further, when the layer thickness of the top coat layer 7 exceeds 15 μm, cracks and cracks may occur during bending, which may cause problems in design and deterioration of weather resistance.

(Primer layer)
As the material of the primer layer 8, basically the same material as that of the pattern layer 5 can be used. Considering that the primer layer 8 is applied to the back surface of the decorative sheet 1 and is wound in a web shape, in order to avoid blocking and enhance the adhesion with the adhesive, for example, silica is used as the primer layer 8. Inorganic fillers such as alumina, magnesia, titanium oxide and barium sulfate may be added. The coating thickness of the primer layer 8 is preferably in the range of 0.1 μm or more and 3.0 μm or less because the purpose is to ensure adhesion with the base material B. The primer layer 8 is necessary when the colored film 2 has an inert surface such as an olefin-based material, but is not particularly necessary when the surface is active.

<Manufacturing method>
An example of manufacturing the decorative sheet 1 will be described.
A vesicle is encapsulated with a nucleating agent to produce a vesicle of the nucleating agent, and the produced vesicle of the nucleating agent is added to a polypropylene resin to add a resin for the skin layer 4 of the coloring film 2. Make the material.
The nucleating agent vesicle is produced, for example, by encapsulating the nucleating agent in a vesicle having a monolayer film by a supercritical reverse phase evaporation method to form a vesicle.

The polypropylene resin used for the colored layer 3 is preferably mixed with a random polypropylene resin having ethylene content or a known amorphous polypropylene resin within a predetermined range in order to facilitate dispersion of an inorganic pigment described later. As the polypropylene resin used for the skin layer 4, it is preferable to use a homopolypropylene resin having high crystallinity. The polypropylene resin may be used alone or in combination.
The resin material for the colored film 2 is heated and melted, and is molded into a sheet so that the thickness is within the range of 50 μm or more and 150 μm or less by extrusion molding or the like to obtain the colored film 2. At this time, by controlling the cooling time from the crystallization temperature to the curing completion temperature by a known cooling process, the strengths x _c and x _s of the colored layer 3 and the skin layer 4 are set to 0.7 or more and 0. .Control within the range of 9 or less.
Further, if necessary, a pattern layer 5 is formed on the upper surface of the colored film 2 by printing, and at least one layer of the transparent resin layer 6 and the top coat layer 7 is formed on the pattern layer 5 by printing.

<Action and others>
(1) The colored sheet 2 of the present embodiment has a colored layer formed by mixing an inorganic pigment with a polypropylene resin and a skin layer made of a polypropylene resin, and the skin layer 4 contains a nano-sized nucleating agent. The nucleating agent is contained in the state of a vesicle of the nucleating agent contained in the outer membrane, and the thickness of the skin layer 4 is in the range of 3 μm or more and 20 μm or less.
According to this configuration, a nucleating agent that improves the crystallinity of polypropylene is vesicled and added to the skin layer 4 as a nucleating agent vesicle, and the film thickness of the skin layer 4 is optimized to provide excellent scratch resistance. The colored sheet 2 can be provided.

(2) The colored sheet 2 of the present embodiment includes a skin layer 4, a colored 3 layer, and a skin layer 4 in that order, and the thickness ratio of each layer is 1: 6: 1 to 1: 50: 1, and is a Fourier type. When the peak intensity ratios of the colored layer 3 and the skin layer 4 calculated from the absorption spectrum obtained by infrared spectroscopic measurement are x _c and x _s , respectively, x _c <x _s may be set. Further, the tensile elastic modulus of the colored film 2 may be in the range of 1000 MPa or more and 2200 MPa or less.
According to this configuration, it is possible to provide the colored sheet 2 which is excellent in concealing property and has both scratch resistance and bending workability.

(3) In the colored sheet 2 of the present embodiment, the amount of the nucleating agent vesicle added to the skin layer 4 of the colored sheet 2 is converted into the nucleating agent in the nucleating agent vesicle with respect to 100 parts by mass of the polypropylene resin. It is preferably in the range of 0.01 part by mass or more and 0.5 part by mass or less.
According to this configuration, the crystallinity of the polypropylene constituting the skin layer 4 is sufficiently improved, and the required tensile elastic modulus, that is, the tensile elastic modulus in the range of 1000 MPa or more and 2200 MPa or less can be surely secured.

(4) In the colored sheet 2 of the present embodiment, the nucleating agent vesicle is preferably a nucleating agent liposome having an outer membrane made of a phospholipid.
According to this configuration, the compatibility between the resin material, which is the main component of the skin layer 4, and the vesicle can be improved.
(5) In the decorative sheet 1 of the present embodiment, it is preferable that the pattern layer 5 is laminated on one surface of the colored sheet 2.
According to this configuration, the concealing property and the design property of the decorative sheet 1 can be improved.
(6) In the decorative sheet 1 of the present embodiment, it is preferable that at least one layer of the transparent resin layer 6 and the top coat layer 7 is laminated on one surface side of the colored sheet 2.
According to this configuration, the scratch resistance of the decorative sheet 1 can be improved.

[Example]
A specific example of the decorative sheet 1 of the present embodiment will be described below.
(Manufacturing method of nucleating agent vesicle)
First, a method for producing the nucleating agent liposome used in this example will be described.
The nucleating agent liposome uses 100 parts by mass of methanol and 70 parts by mass of a phosphate ester metal salt-based nucleating agent (Adecastab NA-21; manufactured by ADEKA) as a nucleating agent by using the above-mentioned supercritical reverse phase evaporation method. , 5 parts by mass of phosphatidylcholine as a phospholipid constituting the outer membrane of the vesicle is placed in a high-pressure stainless steel container kept at 60 ° C. and sealed, and carbon dioxide is injected into the container so that the pressure becomes 20 MPa. It was in a critical state. Then, the inside of the container was vigorously stirred, and 100 parts by mass of ion-exchanged water was injected. After stirring and mixing for another 15 minutes while keeping the temperature and pressure in a supercritical state, carbon dioxide is discharged from the container and returned to atmospheric pressure to apply a nucleating agent to the vesicle having a monolayer outer membrane made of phospholipids. The encapsulating nucleating agent vesicle was obtained.

(Example 1)
As a raw material for the colored layer 3, 60 parts by mass of a polypropylene resin was added and mixed so as to be 40 parts by mass of a titanium oxide pigment as an inorganic pigment. As a raw material for the skin layer 4, 0.5 parts by mass of a hindered amine-based light stabilizer (BASF's "Kimasorb 944") and a benzotriazole-based ultraviolet absorber (BASF's "Chinubin 328") are used as raw materials for the polypropylene resin. 0.5 parts by mass and the above-mentioned nucleating agent vesicle were added and mixed so as to be 0.01 parts by mass. The mixture of the colored layer 3 and the mixture of the skin layer 4 are co-extruded in the order of the skin layer 4, the colored layer 3, and the skin layer 4 using a melt extruder so as to have a thickness of 3 μm: 150 μm: 3 μm. The colored film 2 was formed. The tensile elastic modulus of the film was measured and found to be 2100 MPa.

(Example 2)
Similar to Example 1, coextrusion was performed using a melt extruder to color the skin layer 4, except that the nucleating agent vesicle added to the skin layer 4 was added so as to be 0.5 parts by mass as a nucleating agent. Film 2 was formed. The tensile elastic modulus of the film was measured and found to be 2195 MPa.
(Example 3)
Using the same mixture of colored layer 3 and skin layer 4 as in Example 1, a melt extruder so that the thickness of skin layer 4, colored layer 3, and skin layer 4 is 20 μm: 120 μm: 20 μm in this order. The colored film 2 was formed by co-extrusion using the above. The tensile elastic modulus of the film was measured and found to be 2050 MPa.

(Example 4)
Similar to Example 3, coextrusion was performed using a melt extruder to color the skin layer 4, except that the nucleating agent vesicle added to the skin layer 4 was added so as to be 0.5 parts by mass as a nucleating agent. Film 2 was formed. The tensile elastic modulus of the film was measured and found to be 2145 MPa.
(Example 5)
Using the same mixture of colored layer 3 and skin layer 4 as in Example 1, a melt extruder so that the thickness of skin layer 4, colored layer 3, and skin layer 4 is 30 μm: 100 μm: 30 μm in that order. The colored film 2 was formed by co-extrusion using the above. The tensile elastic modulus of the film was measured and found to be 2000 MPa.

(Example 6)
Similar to Example 5, coextrusion was performed using a melt extruder to color the skin layer 4, except that the vesicle of the nucleating agent added to the skin layer 4 was added as a nucleating agent so as to be 0.5 parts by mass. Film 2 was formed. The tensile elastic modulus of the film was measured and found to be 2095 MPa.
(Example 7)
Using the same mixture of colored layer 3 and skin layer 4 as in Example 1, a melt extruder so that the thickness of skin layer 4, colored layer 3, and skin layer 4 is 30 μm: 120 μm: 30 μm in this order. The colored film 2 was formed by co-extrusion using the above. The tensile elastic modulus of the film was measured and found to be 2075 MPa.

(Example 8)
Similar to Example 7, coextrusion was performed using a melt extruder to color the skin layer 4, except that the nucleating agent vesicle added to the skin layer 4 was added as a nucleating agent so as to be 0.5 parts by mass. Film 2 was formed. The tensile elastic modulus of the film was measured and found to be 2170 MPa.
(Example 9)
Using the same mixture of colored layer 3 and skin layer 4 as in Example 1, the tensile elastic modulus of the film has a thickness of 3 μm: 150 μm: 3 μm in the order of skin layer 4, colored layer 3, and skin layer 4. The colored film 2 was formed by co-extruding using a melt extruder so that the pressure was 1050 MPa.

(Example 10)
Similar to Example 9, coextrusion is performed using a melt extruder to color the skin layer 4, except that the vesicle of the nucleating agent added to the skin layer 4 is added as a nucleating agent so as to be 0.5 parts by mass. Film 2 was formed. The tensile elastic modulus of the film was measured and found to be 1150 MPa.
(Example 11)
Using the same mixture of the colored layer 3 and the mixture of the skin layer 4 as in Example 1, the thickness of the skin layer 4, the colored layer 3, and the skin layer 4 is 1.5 μm: 150 μm: 1.5 μm in this order. The colored film 2 was formed by coextruding with a melt extruder. The tensile elastic modulus of the film was measured and found to be 2100 MPa.

(Example 12)
Except for adding 40 parts by mass of titanium oxide pigment as an inorganic pigment and 0.01 part by mass of the nucleating agent vesicle as an inorganic pigment to 60 parts by mass of polypropylene resin as a raw material of the colored layer 3, the same as in Example 1. Similarly, the colored film 2 was formed by co-extruding using a melt extruder. The tensile elastic modulus of the film was measured and found to be 2300 MPa.
(Example 13)
The nucleating agent vesicle to be added to the skin layer 4 described above was added as a nucleating agent in an amount of 0.5 parts by mass. Further, using the same mixture of the colored layer 3 and the mixture of the skin layer 4 as in Example 1, the skin layer 4, the colored layer 3, and the skin layer 4 are melted in this order so as to have a thickness of 7 μm: 140 μm: 7 μm. The colored film 2 was formed by co-extrusion using an extruder. The tensile elastic modulus of the film was measured and found to be 2200 MPa.

(Example 14)
The nucleating agent vesicle to be added to the skin layer 4 described above was added as a nucleating agent in an amount of 0.5 parts by mass. Further, using the same mixture of the colored layer 3 and the mixture of the skin layer 4 as in Example 1, the skin layer 4, the colored layer 3, and the skin layer 4 are melted in this order so as to have a thickness of 5 μm: 150 μm: 5 μm. The colored film 2 was formed by co-extrusion using an extruder. The tensile elastic modulus of the film was measured and found to be 2205 MPa.

(Example 15)
The pattern layer 5 was formed by printing a pattern on the surface of the colored film 2 having a thickness of 156 μm, which was produced in the same manner as in Example 1. For the pattern layer 5, 0.5 parts by mass of a hindered amine-based light stabilizer (Kimasorb 944; manufactured by BASF) was added to the binder resin content of the two-component urethane ink (V180; manufactured by Toyo Ink Co., Ltd.). It was formed using the ink used. In addition, a primer layer 8 was formed on the back surface of the colored film 2. The primer layer 8 was formed by printing the same two-component urethane ink as the pattern layer 5. Further, a two-component curable urethane top coat (“W184” manufactured by DIC Graphics Corporation) was applied at a coating amount of 3 g / m ² to form a top coat layer 7. In this way, the decorative sheet 1 shown in FIG. 3 was obtained.

(Example 16)
A top coat layer 7 was formed on the colored film 2 having a thickness of 156 μm prepared in the same manner as in Example 2 in the same manner as in Example 15 to obtain a decorative sheet 1.
(Example 17)
A top coat layer 7 was formed on the colored film 2 having a thickness of 160 μm prepared in the same manner as in Example 3 in the same manner as in Example 15 to obtain a decorative sheet 1.
(Example 18)
A top coat layer 7 was formed on the colored film 2 having a thickness of 160 μm prepared in the same manner as in Example 4 in the same manner as in Example 15 to obtain a decorative sheet 1.

(Example 19)
A top coat layer 7 was formed on the colored film 2 having a thickness of 160 μm prepared in the same manner as in Example 5 in the same manner as in Example 15 to obtain a decorative sheet 1.
(Example 20)
A top coat layer 7 was formed on the colored film 2 having a thickness of 160 μm prepared in the same manner as in Example 6 in the same manner as in Example 15 to obtain a decorative sheet 1.
(Example 21)
A top coat layer 7 was formed on the 180 μm-thick colored film 2 produced in the same manner as in Example 7 in the same manner as in Example 15 to obtain a decorative sheet 1.

(Example 22)
A top coat layer 7 was formed on the 180 μm-thick colored film 2 produced in the same manner as in Example 8 in the same manner as in Example 15 to obtain a decorative sheet 1.
(Example 23)
A top coat layer 7 was formed on the colored film 2 having a thickness of 156 μm prepared in the same manner as in Example 9 in the same manner as in Example 15 to obtain a decorative sheet 1.
(Example 24)
A top coat layer 7 was formed on the colored film 2 having a thickness of 156 μm prepared in the same manner as in Example 10 in the same manner as in Example 15 to obtain a decorative sheet 1.

(Example 25)
A top coat layer 7 was formed on the colored film 2 having a thickness of 153 μm produced in the same manner as in Example 11 in the same manner as in Example 15 to obtain a decorative sheet 1.
(Example 26)
A top coat layer 7 was formed on the colored film 2 having a thickness of 156 μm prepared in the same manner as in Example 12 in the same manner as in Example 15 to obtain a decorative sheet 1.
(Example 27)
A top coat layer 7 was formed on the colored film 2 having a thickness of 154 μm prepared in the same manner as in Example 13 in the same manner as in Example 15 to obtain a decorative sheet 1.

(Example 28)
A top coat layer 7 was formed on the colored film 2 having a thickness of 160 μm prepared in the same manner as in Example 14 in the same manner as in Example 15 to obtain a decorative sheet 1.
(Example 29)
The colored film 2 was formed by co-extrusion using a melt extruder in the same manner as in Example 1 except that a nucleating agent having no outer film was used instead of the nucleating agent vesicle described above. The tensile elastic modulus of the film was measured and found to be 2050 MPa.

(Example 30)
The colored film 2 was formed by co-extrusion using a melt extruder in the same manner as in Example 2 except that a nucleating agent having no outer film was used instead of the nucleating agent vesicle described above. The tensile elastic modulus of the film was measured and found to be 2145 MPa.
(Example 31)
The colored film 2 was formed by co-extrusion using a melt extruder in the same manner as in Example 3 except that a nucleating agent having no outer film was used instead of the nucleating agent vesicle described above. The tensile elastic modulus of the film was measured and found to be 2000 MPa.

(Example 32)
The colored film 2 was formed by co-extrusion using a melt extruder in the same manner as in Example 4 except that a nucleating agent having no outer film was used instead of the nucleating agent vesicle described above. The tensile elastic modulus of the film was measured and found to be 2095 MPa.
(Comparative Example 1)
The colored film 2 was formed by co-extrusion using a melt extruder in the same manner as in Example 1 except that the above-mentioned vesicle of the nucleating agent was not added. The tensile elastic modulus of the film was measured and found to be 800 MPa.

(Comparative Example 2)
As a raw material for the colored layer 3, 40 parts by mass of a titanium oxide pigment as an inorganic pigment and 0.01 parts by mass of the above-mentioned nucleating agent vesicle were added to 60 parts by mass of a polypropylene resin and mixed. As a raw material for the skin layer 4, 0.5 parts by mass of a hindered amine-based light stabilizer (BASF's "Kimasorb 944") and a benzotriazole-based ultraviolet absorber (BASF's "Chinubin 328") are used as raw materials for the polypropylene resin. It was added and mixed so as to be 0.5 parts by mass. The mixture of the colored layer 3 and the mixture of the skin layer 4 are co-extruded in the order of the skin layer 4, the colored layer 3, and the skin layer 4 using a melt extruder so as to have a thickness of 3 μm: 150 μm: 3 μm. The colored film 2 was formed. The tensile elastic modulus of the film was measured and found to be 2100 MPa.

(Comparative Example 3)
The colored film 2 was formed by co-extrusion using a melt extruder in the same manner as in Example 1 except that an untreated nucleating agent was used instead of the above-mentioned nucleating agent vesicle. The tensile elastic modulus of the film was measured and found to be 1450 MPa.
(Comparative Example 4)
The colored film 2 was formed by coextrusion using a melt extruder in the same manner as in Example 2 except that an untreated nucleating agent was used instead of the above-mentioned nucleating agent vesicle. The tensile elastic modulus of the film was measured and found to be 1540 MPa.

(Comparative Example 5)
The colored film 2 was formed by co-extrusion using a melt extruder in the same manner as in Example 3 except that an untreated nucleating agent was used instead of the above-mentioned nucleating agent vesicle. The tensile elastic modulus of the film was measured and found to be 1400 MPa.
(Comparative Example 6)
The colored film 2 was formed by coextrusion using a melt extruder in the same manner as in Example 4 except that an untreated nucleating agent was used instead of the above-mentioned nucleating agent vesicle. The tensile elastic modulus of the film was measured and found to be 1490 MPa.

[Evaluation]
For Examples 1 to 2 and Comparative Examples 1 to 6 above, Fourier infrared spectroscopic measurement, tensile elastic modulus measurement, pigment-induced defects (extrusion suitability), scratch resistance, bending suitability, and wrapping smoothness (wrapping). Surface uniformity during processing) was evaluated.

<Fourier infrared spectroscopy>
Fourier infrared spectrometry, using Perkin Elmer Fourier infrared spectroscopic measurement device (Spectrum Spotlight 400), to obtain the absorbance spectrum of 700 cm ^-1 from 4000 cm ^-1. The peak intensity ratios of wave numbers 997 cm ^-1 , 973 cm ^-1 , and 938 cm ^-1 were extracted from the obtained absorption spectrum, and the peak intensity ratio x was calculated by the following formula.

In this embodiment, the colored film 2 has a two-kind three-layer structure composed of a colored layer 3 and a skin layer 4. Infrared spectroscopy measures the cross section of the colored film 2. At this time, the peak intensity ratio x of the colored layer is represented by x _c , and the peak intensity ratio x of the skin layer is represented by x _s .

<Tensile modulus>
The tensile elastic modulus was measured by using an autograph (AGS-500NX) manufactured by Shimadzu Corporation and conducting a tensile test at a tensile speed of 50 mm / min to calculate the tensile elastic modulus.
<Problems caused by pigments>
When the colored film 2 was co-extruded using a melt extruder, the defect that the pigment was deposited on the T stand and the film formation was poor was evaluated. If there is no problem with no pigment precipitation, "○", if the pigment adheres to the T stand, but there is no problem with film formation, "△", a large amount of pigment precipitates on the T stand, resulting in poor film formation. The case of causing is set as "x". If the evaluation is "Δ" or higher, there is no problem in the quality of the colored film.

<Concealment>
The concealment property was evaluated by using a spectrophotometer (530JP / LP) manufactured by x-rite, and the color difference measured between the white background and the black background of the concealment test paper (byko-chart high brightness 2A) manufactured by BYK-GARDNER. Judged by. The smaller the color difference, the better the hiding property, and if it is practically 0.5 or less, there is no problem in the quality of the colored film.

<Scratch resistance>
The scratch resistance was evaluated by conducting a pencil hardness test. First, on one surface of the medium density fiberboard (MDF) as the substrate B, each sheet of Examples 1 to 32 and Comparative Examples 1 to 6 obtained by the above method was applied with a urethane-based adhesive. I pasted it. In the pencil hardness test, a 3B pencil was used, the angle of the pencil was fixed at 45 ± 1 ° with respect to the surface of each sheet, and the surface condition was observed by sliding the pencil with a load of 750 kg applied. (Compliant with the old JIS standard JIS K5400). The test was carried out 5 times to evaluate the scratches and marks on the pencil.
"◎" if there are no scratches or marks, "○" if you can see a slight pencil mark, "△" if you can see a pencil mark, "△" if you can see a scratch or tear on the sheet. × ”.
If the evaluation is "○" or higher, there is no practical problem. Further, if the evaluation is "Δ" or higher, the problem does not occur although it is limited to applications such as furniture and a vertical surface at a high position where people do not touch. It is preferable that the evaluation is "○" or higher.

<Bending process suitability>
In the bending aptitude test, each sheet is attached to the substrate B as in the pencil hardness test, and a V-shaped groove is formed on the other surface of the substrate B so that the decorative sheet 1 on the opposite side is not scratched. Insert until the boundary where B and the decorative sheet 1 are bonded together. Next, the substrate B is bent up to 90 degrees along the V-shaped groove so that the surface of the decorative sheet 1 is mountain-folded, and whether the bent portion of the surface of the decorative sheet 1 is whitened or cracked. Was observed using an optical microscope, and the state of bending workability was evaluated.
"◎" if no whitening or cracks are seen, "○" if some whitening is visible, "△" if some whitening is visible, or if whitening is visible on the entire surface or partly The case where a crack is visible is marked with "x". If the evaluation is "Δ" or higher, there is no problem in practical use.

<Surface uniformity during lapping>
In the surface uniformity test during the lapping process, a square lumber in which 3 to 5 plate materials or particle boards were bonded between two medium density fiberboards (MDF) was used as the substrate B, and the results were obtained by the above method. Each of the decorative sheets 1 of Examples 1 to 2 and Comparative Examples 1 to 6 was attached by lapping using a hot melt adhesive to obtain a decorative board. Subsequently, the surface on which the decorative sheet 1 was attached was observed at the end of the plate material, and visually observed whether there was surface unevenness due to the unevenness of the plate material or the step difference of the bonded portion of the plate material. Further, the obtained decorative board was left to stand in an environment of a temperature of 80 ° C. and a humidity of 85% for 1000 hours, and surface irregularities at the same location and peeling of the decorative sheet 1 were confirmed.
"◎" when the surface is smooth without any unevenness or steps even after the initial stage and 1000 hours, "○" when the surface looks slightly rough, "△" when some unevenness or steps are visible, the entire surface The case where unevenness or a step was seen, or the case where the decorative sheet 1 was peeled off after 1000 hours was marked with "x". If the evaluation is “Δ” or higher, there is no problem in practical use, but it is preferable that the evaluation is “◯” or higher.

<Printing suitability>
The pattern layer 5 was formed by gravure printing using a gravure printing machine, and at that time, a defect in which the colored film 2 was stretched by tension and misplaced when laminating each color was evaluated as a printing defect. "◎" when registration adjustment is not required at all, "○" when easy adjustment is possible by automatic registration adjustment, "△" when registration adjustment requires attention, printing cannot be continued because registration adjustment is not possible. The case was set as "x". In addition, when the film being printed breaks frequently and there is a problem in mass productivity, it is also marked with "x". If the evaluation is "Δ" or higher, there is no problem in printing.

The results of these evaluations are shown in Table 1.

As can be seen from Table 1, the decorative sheets of Examples 1 to 14 and 29 to 32 have good concealing properties without causing problems caused by pigments, and are bent while ensuring a state in which they can withstand practical use in terms of strength. It can be seen that both are achieved. Further, it can be seen that in the decorative sheets of Examples 15 to 28, the pattern layer 5 and the top coat layer 7 are laminated on Examples 1 to 14, and the bending process can be achieved while achieving both high design and high scratch resistance. ..
In the decorative sheets of Examples 5 to 6, since the skin layer 4: the colored layer 3: the skin layer 4 was prepared in a ratio of 1: 3.3: 1, the hiding property showed a large value of 0.48 to 0.49. However, there was no problem in practical use.

Since the decorative sheets of Examples 7 to 8 were made of a thick film with a thickness of the colored film 2 of 180 μm, the film was rigid and the smoothness during the wrapping process was deteriorated, but it was at a level where there was no problem in practical use. It was.
Since the elastic modulus of the decorative sheets of Examples 9 to 10 was controlled to 1050 to 1150 MPa depending on the production conditions, the scratch resistance and the smoothness during the lapping process were deteriorated, but the level was not a problem in practical use.
In the decorative sheet of Example 11, the skin layer 4 was made of a thin film of 1.5 μm, but the pigment was attached to the T stand at the time of film formation. However, there was no problem in film formation, and the level was not a problem in terms of quality.
In the decorative sheet of Example 12, since the nucleating agent was added to both the colored layer 3 and the skin layer 4, the film was rigid and the smoothness of the bending process and the lapping process was deteriorated, but this was not a quality problem. Met.

On the other hand, in the decorative sheet of Comparative Example 1, since the skin layer 4 did not use a nano-sized nucleating agent, the strength was not sufficiently improved by improving the crystallinity, and the scratch resistance was remarkably deteriorated.
Further, in the decorative sheet of Comparative Example 2, a nano-sized nucleating agent is used for the colored layer 3, but not used for the skin layer 4. Although the crystallinity of the colored film 2 sufficiently satisfies the specified range, the surface layer is flexible and the scratch resistance is remarkably deteriorated because the crystallization of the skin layer 4 does not proceed.
Further, in the decorative sheets of Comparative Examples 3 to 6, since a micro-sized nucleating agent which was not vesicled was used, the strength was not sufficiently improved by improving the crystallinity, and the scratch resistance was remarkably deteriorated. If the amount of the nucleating agent added is increased, the scratch resistance is improved, but the bending process is deteriorated, so that a decorative sheet exhibiting the desired characteristics cannot be obtained.

From the above, it was clarified that the decorative sheets of Examples 1 to 32 are decorative sheets having all of the defects caused by the pigment, the hiding property, the scratch resistance, and the bending processability. Furthermore, it was revealed that the decorative sheets of Examples 1 to 32 also have smoothness by lapping.
The decorative sheet of the present invention is not limited to the above-described embodiments and examples, and various modifications can be made as long as the features of the invention are not impaired.

1 ... decorative sheet, 2 ... colored film (colored sheet), 3 ... colored layer, 4 ... skin layer, 5 ... pattern layer, 6 ... transparent resin layer, 6a ... embossed pattern, 6b ... adhesive resin layer, 7 ... top Coat layer, 8 ... Primer layer, B ... Base material

Claims (14)

It has a colored layer containing an inorganic pigment and a polypropylene resin, and a skin layer containing a polypropylene resin.
A colored sheet characterized in that the skin layer is formed by adding a nano-sized nucleating agent. The colored sheet according to claim 1, wherein the thickness of the skin layer is within the range of 3 μm or more and 20 μm or less. Claim 1 or claim, wherein the skin layer, the colored layer, and the skin layer are sequentially provided, and the thickness ratio of each layer is within the range of 1: 6: 1 to 1:50: 1. 2. The colored sheet according to 2. With respect to the colored layer and the skin layer, when the peak intensity ratios calculated from the absorption spectra obtained by Fourier infrared spectroscopy using the following formulas are x _c and x _s , respectively, x _c <x _s . The colored sheet according to any one of claims 1 to 3, wherein the colored sheet is characterized by being present.
Here, in the following equation, I ₉₉₇ indicates a peak intensity value of wave number ₉₉₇ cm ^-1 , I ₉₃₈ indicates a peak intensity value of wave number ₉₃₈ cm ^-1 , and I ₉₇₃ indicates a peak intensity value of wave number ₉₇₃ cm ^-1 .

The colored sheet according to any one of claims 1 to 4, wherein the tensile elastic modulus is in the range of 1000 MPa or more and 2200 MPa or less. Claims 1 to 5 are characterized in that the amount of the nano-sized nucleating agent added is in the range of 0.01 parts by mass or more and 0.5 parts by mass or less with respect to 100 parts by mass of the polypropylene resin. The colored sheet according to any one of the above. Any one of claims 1 to 6, wherein the nano-sized nucleating agent is a nucleating agent vesicle in which the nucleating agent is contained in a vesicle having an outer film of a monolayer film. The colored sheet described in the section. The nucleating agent vesicle is added to 100 parts by mass of the polypropylene resin within a range of 0.01 part by mass or more and 0.5 part by mass or less in terms of the nucleating agent in the nucleating agent vesicle. The colored sheet according to claim 7. The colored sheet according to claim 7 or 8, wherein the nucleating agent vesicle is a nucleating agent liposome having an outer membrane made of a phospholipid. The colored sheet according to any one of claims 7 to 9, wherein the nucleating agent is encapsulated in the vesicle by a supercritical reverse phase evaporation method. A decorative sheet comprising at least the colored sheet according to any one of claims 1 to 10 and a top coat layer. The method for manufacturing a decorative sheet according to claim 11.
A colored layer in which an inorganic pigment is mixed with a polypropylene resin and a skin layer containing a polypropylene resin are produced, and the thickness of the skin layer is within the range of 3 μm or more and 20 μm or less, and the skin layer, the colored layer, and the skin A method for producing a decorative sheet, which comprises producing a colored sheet having a layer thickness ratio of 1: 6: 1 to 1: 50: 1. The method for producing a decorative sheet according to claim 12, wherein when the colored sheet is produced, the tensile elastic modulus of the colored sheet is controlled within the range of 1000 MPa or more and 2200 MPa or less. The method for producing a decorative sheet according to claim 12 or 13, wherein the nucleating agent is encapsulated in a vesicle by a supercritical reverse phase evaporation method.

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