Method for manufacturing transfer sheets and melamine decorative laminates

Abstract

To provide a transfer sheet that enables selective transfer of a transfer layer to a transfer object and can maintain excellent designability of the transfer object, and a method for manufacturing a melamine decorative board.SOLUTION: A transfer sheet 1 comprises: a base material layer 2; a transfer layer 3 provided on a side of one surface 2a of the base material layer 2; and an adhesion layer 4 provided on a side of a surface 3a of the transfer layer 3 opposite to the base material layer 2. As a resin constituting the transfer layer 3, an uncured ionizing radiation curable resin and a chlorinated polyolefin resin are used. As a resin constituting the adhesion layer 4, a thermosetting resin that does not contain any component that exhibits liquid repellency is used.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a transfer sheet and a melamine decorative board.

Background Art

[0002] Conventionally, for example, a transfer sheet has been proposed in which a transfer layer and an adhesion layer are laminated in this order on one surface side of a base material layer, and the transfer layer contains a cured product of a radiation-curable resin (see, for example, Patent Document 1). In the transfer sheet described in Patent Document 1, a transfer sheet is laminated on a laminate in which a core layer and an uncured melamine resin layer are laminated, and heating and pressing are performed (thermal pressure transfer) to cure the uncured melamine resin layer to produce a melamine decorative board. In addition, as a laminate to be laminated with the transfer sheet, there is one provided with a base paper, a pattern layer, and a liquid repellent layer that imparts a gloss difference synchronized with the pattern of the pattern layer (see, for example, Patent Document 2).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] In order to maintain the excellent design property of the laminate by laminating (transferring) the transfer layer, the transfer sheet is required to suppress transfer defects such as being transferred to locations other than the locations to be transferred. For this reason, it is important for the transfer sheet to enable selective transfer of the transfer layer to the transfer object and maintain the excellent design property of the transfer object. However, the conventional transfer sheet has a problem that selective transfer of the transfer layer to the transfer object cannot be sufficiently achieved. The present invention focuses on the points mentioned above and aims to provide a method for manufacturing a transfer sheet and a melamine decorative laminate that enables selective transfer of the transfer layer to the object to be transferred and maintains the excellent design properties of the object to be transferred. [Means for solving the problem]

[0005] To solve the above problems, one aspect of the present invention provides a transfer sheet comprising (a) a base layer, (b) a transfer layer provided on one side of the base layer, (c) an adhesion layer provided on the side of the transfer layer opposite to the base layer, (d) a resin constituting the transfer layer being an uncured ionizing radiation-curable resin and a chlorinated polyolefin resin, and (e) a resin constituting the adhesion layer being a thermosetting resin that does not contain components that exhibit liquid repellency.

[0006] Another aspect of the present invention is a method for manufacturing a melamine decorative laminate using the above-mentioned transfer sheet, comprising the steps of: (a) immersing a first laminate having a core layer and a liquid-repellent layer partially provided on one side of the core layer in an aqueous melamine resin solution; applying pressure and heat to a second laminate formed by laminating a transfer sheet on the liquid-repellent layer side of the immersed first laminate to cure the uncured aqueous melamine resin solution contained in the core layer; (c) peeling the base material layer of the transfer sheet from the first laminate and transferring a portion of the transfer layer of the transfer sheet, which contains the uncured ionizing radiation-curable resin and the chlorinated polyolefin resin, to the first laminate; and (d) irradiating the first laminate with ionizing radiation to cure the ionizing radiation-curable resin of the transfer layer. [Effects of the Invention]

[0007] According to one aspect of the present invention, it is possible to provide a method for manufacturing a transfer sheet and a melamine decorative laminate that enables selective transfer of a transfer layer to an object to be transferred and maintains the excellent design properties of the object to be transferred. [Brief explanation of the drawing]

[0008] [Figure 1]This is a cross-sectional view showing a transfer sheet according to an embodiment of the present invention. [Figure 2] This diagram illustrates how to use the transfer sheet, where (a) is a cross-sectional view representing the first laminate, (b) is a cross-sectional view representing the second laminate, and (c) is a cross-sectional view representing the melamine decorative laminate. [Modes for carrying out the invention]

[0009] Next, embodiments of the present invention will be described with reference to the drawings. Here, the drawings are schematic, and the relationship between thickness and planar dimensions, the ratio of the thickness of each layer, etc., may differ from reality. Furthermore, the embodiments shown below illustrate configurations for realizing the technical concept of the present invention, and the technical concept of the present invention is not limited to the materials, shapes, and structures of the components described below. The technical concept of the present invention can be modified in various ways within the technical scope defined by the claims described in the patent claims.

[0010] (Transfer sheet) As shown in Figure 1, the transfer sheet 1 of this embodiment is formed by laminating a transfer layer 3 and an adhesion layer 4 in that order on one side 2a of the base layer 2.

[0011] (base material layer) The base layer 2 is the base layer of the transfer sheet 1. For the base layer 2, a material with high flexibility is preferred in terms of ease of peeling after transfer. For example, polyester resins such as polyethylene terephthalate resin, polybutylene terephthalate resin, polyethylene naphthalate-isophthalate copolymer resin, and polyester thermoplastic elastomers; polyolefin resins such as polyethylene resin, polypropylene resin, polymethylpentene resin, and olefin thermoplastic elastomers; and thin paper laminated with polyolefin resin on its surface can be used. Polyester resin is particularly preferred in terms of heat resistance and dimensional stability. At least one of the following is applied to a part or the entire surface 2a of the base layer 2: a mirror finish and a matte finish. The gloss value of the matte-finished area is not particularly limited.

[0012] (Transfer layer) The transfer layer 3 is a layer that is transferred to the first laminate 8 (described later) used in the manufacture of the melamine decorative laminate 12. The resins that make up the transfer layer 3 are an uncured ionizing radiation-curable resin and a chlorinated polyolefin resin. As ionizing radiation-curable resins, for example, resins that undergo a crosslinking polymerization reaction upon irradiation with ionizing radiation and transform into a three-dimensional polymer structure can be used. As ionizing radiation, for example, electromagnetic waves or charged particle beams that have energy quanta capable of polymerizing or crosslinking molecules can be used. Examples include ultraviolet (UV), electron beams (EB), electromagnetic waves, and charged particle beams. As ionizing radiation-curable resins, at least one of ultraviolet-curable resins and electron beam-curable resins is preferred because they have tack-free properties where the resin does not adhere after heat drying alone, and after-curing properties where they can be cured by irradiation with ultraviolet or electron beams even after heat-press transfer.

[0013] The UV-curable resin is not particularly limited, and a transparent resin mainly composed of a prepolymer (including oligomers) and / or monomer containing a radically polymerizable double bond in its molecule that can undergo polymerization and crosslinking reactions upon irradiation with ultraviolet light can be used. As the prepolymer or monomer, compounds having radically polymerizable unsaturated groups such as (meth)acryloyl groups and (meth)acryloyloxy groups, or cationic polymerizable functional groups such as epoxy groups in their molecules can be used. Polyene / thiol-based prepolymers formed by a combination of polyene and polythiol are also preferred. Here, (meth)acryloyl group means acryloyl group or methacryloyl group.

[0014] Examples of prepolymers having radically polymerizable unsaturated groups include polyester (meth)acrylate, urethane (meth)acrylate, epoxy (meth)acrylate, and melamine. Examples include (meth)acrylates of amines, (meth)acrylates of triazines, and (meth)acrylates of silicones. The molecular weights of these are preferably about 250 to 100,000. Examples of the monomer having a radically polymerizable unsaturated group include, for example, methyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and phenoxyethyl (meth)acrylate. Further, examples include diethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, trimethylolpropane ethylene oxide tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and the like.

[0015] Examples of the prepolymer having a cationically polymerizable functional group include prepolymers of epoxy resins such as bisphenol type epoxy resins and novolac type epoxy compounds, and vinyl ether resins such as fatty acid vinyl ethers and aromatic vinyl ethers. Examples of the thiol include polythiols such as trimethylolpropane trithioglycolate and pentaerythritol tetrathioglycolate. Further, examples of the polyene include those obtained by adding allyl alcohol to both ends of a polyurethane formed from a diol and a diisocyanate.

[0016] The electron beam curable resin is not particularly limited, and examples include unsaturated polyesters, vinyl group-containing compounds, acrylic acid (methacrylic acid) ester compounds, and the like. Examples of the acrylic acid ester compound include one or more kinds of oligomers or prepolymers such as urethane acrylate, polyester acrylate, polyol acrylate, epoxy acrylate, and polyester acrylate having one or more acrylic groups.

[0017] The chlorinated polyolefin resin is not particularly limited, and for example, chlorinated polyethylene resin, chlorinated polypropylene resin, chlorinated ethylene-propylene copolymer, chlorinated ethylene-vinyl acetate copolymer, etc. can be adopted. When the transfer layer 3 contains a chlorinated polyolefin resin, the adhesion between the transfer layer 3 and the substrate layer 2, which is the coating surface of the transfer layer 3, is improved as compared with the case where the chlorinated polyolefin resin is not contained. When the adhesion between the transfer layer 3 and the substrate layer 2 is improved by adding the chlorinated polyolefin resin, it becomes possible to appropriately increase the weight of the peeling of the substrate layer 2 from the transfer layer 3 (the tensile force required for peeling). Thereby, when transferring the transfer layer 3 to the first laminate 8, transfer defects such as the transfer of the ionizing radiation curable resin of the transfer layer 3 to non-transfer locations (for example, locations where the liquid repellent layer 7 is present in the first laminate 8) are suppressed, and it becomes possible to transfer only to the locations where the transfer layer 3 should be transferred (for example, locations where there is no liquid repellent layer 7 (described later) in the first laminate 8) (selective transfer).

[0018] Thus, in the transfer sheet 1, when the transfer layer 3 contains a chlorinated polyolefin resin, the adhesion between the transfer layer 3 and the substrate layer 2 is improved, and selective transfer of the transfer layer 3 to the first laminate 8, which is the transfer object, becomes possible. For this reason, it is possible to maintain excellent design properties (tactile feel and high matte design) due to the design (the pattern layer 6 of the first laminate 8 described later) applied to the first laminate 8. Furthermore, the transfer layer 3 of the transfer sheet 1 can surely exhibit physical properties such as easy cleaning property, scratch resistance, and fingerprint resistance on the first laminate 8, which is the transfer object. In addition, by suppressing transfer defects of the transfer layer 3 on the first laminate 8, the adhesion between the transfer layer 3 and the adhesion layer 4, and thus the adhesion between the transfer layer 3 and the first laminate 8, can be improved during hot press transfer in the manufacture of the melamine decorative board 12. [[ID=eleven]] [[ID=twelve]]

[0019] [[ID=thirteen]] Thus, the transfer layer 3 in the transfer sheet 1 contains a chlorinated polyolefin resin as an additive to improve adhesion with the substrate layer 2 and enable selective transfer to the object to be transferred (first laminate 8). By enabling selective transfer, the excellent design properties of the object to be transferred (in this example, the first laminate 8) can be maintained. Furthermore, it is preferable to use chlorinated polypropylene resin as the chlorinated polyolefin resin. This ensures that the adhesion between the base layer 2 (for example, thin paper laminated with polyolefin resin) and the transfer layer 3 is reliably improved.

[0020] As will be explained in more detail later, the adhesion layer 4, through heat-pressure transfer during the manufacturing of the melamine decorative laminate 12, bonds with the pattern layer 6 of the first laminate 8, but does not bond with the liquid-repellent layer 7 (described later). Therefore, in the first laminate 8, the peeling weight X of the transfer sheet 1 in the portion of the transfer layer 3 that is the target of transfer (the portion where the adhesion layer 4 bonds with the pattern layer 6) is heavier than the peeling weight Y of the transfer sheet 1 in the portion of the transfer layer 3 that is not the target of transfer (the portion where the liquid-repellent layer 7 is located). Therefore, by making the peeling weight A of the base layer 2 from the transfer layer 3 in the transfer sheet 1 satisfy the following relation (1), selective transfer of the transfer layer 3 to the first laminate 8, which is the transfer target, becomes more reliable. X>A>Y···(1)

[0021] In order to suitably control the peeling weight A of the substrate layer 2 from the transfer layer 3 so as to satisfy the above relation, in this embodiment, the content of chlorinated polyolefin resin in the transfer layer 3 is preferably in the range of 0.1% by mass or more and 10% by mass or less relative to the main component, the ionizing radiation-curable resin. If the content of the chlorinated polyolefin resin in the transfer layer 3 is within the above range, the weight A of the peeling of the base material layer 2 from the transfer layer 3 can be preferably controlled so as to satisfy the above relational expression. That is, at the time of transferring the transfer layer 3 to the first laminate 8, transfer failure such as the ionizing radiation curable resin of the transfer layer 3 being transferred to a non-transfer portion (for example, a portion where the liquid repellent layer 7 is present in the first laminate 8) can be surely suppressed, and it becomes possible to surely transfer the transfer layer 3 only to the portion to be transferred (for example, a portion where the liquid repellent layer 7 is not present in the first laminate 8) (selective transfer). Therefore, if the content of the chlorinated polyolefin resin in the transfer layer 3 is within the above range, selective transfer of the transfer layer 3 to the first laminate 8, which is the transfer object, can be surely achieved, and excellent design properties (touch feeling and high matte design) due to the design (pattern layer 6 of the first laminate 8) applied to the first laminate 8 can be surely maintained.

[0022] On the other hand, when the content of the chlorinated polyolefin resin with respect to the ionizing radiation curable resin is not within the above range, it may be difficult to control the above-described peeling weight A. For example, when the content of the chlorinated polyolefin resin is less than 0.1% by mass with respect to the ionizing radiation curable resin, the adhesion between the base material layer 2 and the transfer layer 3 is not sufficiently improved, the peeling weight is insufficient, and the weight A of the peeling of the base material layer 2 from the transfer layer 3 may be lighter than the peeling weight Y of the transfer sheet 1 (A < Y). For this reason, transfer failure such as the transfer layer 3 being transferred to a non-transfer portion (a portion where the liquid repellent layer 7 is present) of the transfer layer 3 in the first laminate 8, that is, the portion of the transfer layer 3 that should remain on the base material layer 2 being transferred to the first laminate 8 may occur. Therefore, selective transfer of the transfer layer 3 may not be achieved. In addition, when the content of the chlorinated polyolefin resin exceeds 10% by mass with respect to the radiation-curable resin, the peeling weight of the base material layer 2 from the transfer layer 3 during thermocompression transfer in the production of the melamine decorative board 12 increases significantly, and the peeling weight A of the base material layer 2 from the transfer layer 3 may become heavier than the peeling weight X of the transfer sheet 1 (X < A). Therefore, in the first laminate 8, the transfer layer 3 may not be transferred to the portion of the transfer target of the transfer layer 3 (the portion without the liquid-repellent layer 7), that is, a general transfer defect may occur where the transfer layer 3 to be transferred remains on the side of the base material layer 2. Therefore, selective transfer may not be achieved in some cases.

[0023] (Adhesive layer) The adhesive layer 4 is a layer for improving the adhesion between the transfer layer 3 and the first laminate 8. As the resin constituting the adhesive layer 4, for example, thermosetting resins such as urethane resins and acrylic resins can be adopted. As the thermosetting resin, it is preferable to adopt a resin that does not contain a component that exhibits liquid-repellent properties, such as silicone oil. Thereby, the adhesive layer 4 can improve the adhesion with the resin (melamine resin, urea-based resin, phenolic resin, etc.) constituting the liquid-repellent layer 7. Further, by adopting a resin that does not contain a component that exhibits liquid-repellent properties, the remaining melamine resin on the liquid-repellent layer 7 of the first laminate 8 during thermocompression transfer can be adhered to the adhesive layer 4, and whitening of the liquid-repellent layer 7 due to the remaining melamine resin can be prevented. Note that as the resin that does not contain a component that exhibits liquid-repellent properties, a resin in which the surface 4a of the adhesive layer 4 on the side opposite to the transfer layer 3 has a contact angle with respect to pure water of 90 degrees or less is preferable, a resin in which the contact angle is 60 degrees or less is more preferable, and a resin in which the contact angle is 30 degrees or less is most preferable. In the transfer sheet 1 according to the present embodiment, since the transfer layer 3 contains a chlorinated polyolefin resin as described above, transfer defects of the transfer layer 3 are suppressed, and the adhesion between the transfer layer 3, the adhesive layer 4, and the first laminate 8 is improved. Further, by removing the remaining melamine resin by the adhesive layer 4, the adhesion between the transfer layer 3 and the first laminate 8 can be further improved. Note that the adhesive layer 4 has a property of being joined to the pattern layer 6 (described later) of the first laminate 8 by thermocompression transfer during the production of the melamine decorative board 12, but not being joined to the liquid-repellent layer 7 (described later).

[0024] (How to use the transfer sheet) Next, a method for using the transfer sheet 1 according to this embodiment will be described. Figure 2 is a diagram illustrating a method for manufacturing a melamine decorative laminate 12 using the transfer sheet 1. First, as shown in Figure 2(a), a first laminate 8 is formed on one surface 5a of the core layer 5, in which the pattern layer 6 and the liquid-repellent layer 7 are laminated in that order. The liquid-repellent layer 7 is partially provided on one surface 5a of the core layer 5, creating a difference in gloss between the areas with and without the liquid-repellent layer 7.

[0025] Here, as the core layer 5, for example, phenol resin-impregnated paper or a laminate thereof can be used. Phenolic resin-impregnated paper can be obtained, for example, by impregnating kraft paper with a resin mainly composed of phenol resin and drying it. Alternatively, as the core layer 5, glass cloth or glass nonwoven fabric may be used, or a prepreg based on glass cloth or glass nonwoven fabric may be used. A prepreg can be obtained, for example, by impregnating glass cloth or glass nonwoven fabric with a resin composition containing a thermoplastic resin, a thermosetting resin, etc. The pattern layer 6 is a layer for imparting a patterned design to the melamine decorative laminate 12. For example, a wood grain pattern can be used as the pattern. The pattern layer 6 can be created using a known printing method. As the printing ink, a water-based ink is preferred from the viewpoint of resin impregnation suitability.

[0026] The liquid-repellent layer 7 is a layer for imparting a design to the melamine decorative laminate 12 through gloss differences. As for the gloss difference, for example, a gloss difference of a vascular pattern that matches the wood grain pattern of the pattern layer 6 can be used. As the resin constituting the liquid-repellent layer 7, for example, a thermosetting resin having a urethane bond, such as a two-component curing urethane resin, or a curable resin such as an ionizing radiation curable resin can be used. As for curable resins, for example, thermosetting resins such as melamine resins, epoxy resins, urea resins, phenolic resins, unsaturated polyester resins, diallyl phthalate resins, benzoguanamine resins, urethane resins, amino alkyd resins, and silicone resins; and ionizing radiation curable resins such as (meth)acrylate resins and unsaturated polyester resins can be used.

[0027] Next, the formed first laminate 8 is immersed in an aqueous melamine resin solution, and then the transfer sheet 1 is laminated onto the surface 8a of the first laminate 8 on the side with the liquid-repellent layer 7 to form the second laminate 9. At this time, any remaining repelled aqueous melamine resin solution on the liquid-repellent layer 7 is removed by the adhesion layer 4 of the transfer sheet 1. Subsequently, as shown in Figure 2(b), the formed second laminate 9 is sandwiched between two mirror plates 10 and 11, and the second laminate 9 is subjected to pressure and heat to cure the uncured aqueous melamine resin solution contained in the core layer 5 (thermal transfer). By thermal transfer, the transfer layer 3 of the transfer sheet 1, which contains the uncured ionizing radiation-curable resin and chlorinated polyolefin resin, is bonded to the pattern layer 6 (hereinafter also referred to as the "cured melamine resin layer 6") via the adhesion layer 4. Note that the portion of the pattern layer 6 on which the liquid-repellent layer 7 is provided is not bonded to the adhesion layer 4. In other words, the portion where the liquid-repellent layer 7 is provided (the portion not bonded to the adhesion layer 4) has easier peelability of the transfer sheet 1 from the first laminate 8 compared to the portion where the liquid-repellent layer 7 is not provided (the portion bonded to the adhesion layer 4).

[0028] Next, as shown in Figure 2(c), the base layer 2 is peeled off from the first laminate 8. When peeling the base layer 2 off from the first laminate 8, the portion of the transfer layer 3 and the adhesion layer 4 that is bonded to the cured melamine resin layer 6 remains on the first laminate 8 side. As a result, the surface 3b of the transfer layer 3 on the base layer 2 side is exposed, and the surface of the melamine decorative laminate 12 is formed on the exposed surface 3b. On the other hand, the portion of the transfer layer 3 and the adhesion layer 4 that is not bonded to the cured melamine resin layer 6, that is, the portion that is in contact with the liquid-repellent layer 7, remains on the base layer 2 side. Specifically, because the transfer layer 3 of the transfer sheet 1 contains chlorinated polyolefin resin, the adhesion between the transfer layer 3 and the base layer 2, which is the coated surface of the transfer layer 3, is improved compared to the case where chlorinated polyolefin resin is not contained. Therefore, as described above, the portions where the transfer layer 3 and adhesion layer 4 are not bonded to the cured melamine resin layer 6 (portions where the transfer sheet 1 is easily peeled from the first laminate 8), i.e., the portions in contact with the liquid-repellent layer 7, remain on the base layer 2 side. On the other hand, in the portions where the transfer layer 3 and adhesion layer 4 are bonded to the cured melamine resin layer 6 (portions where the transfer sheet 1 is heavily peeled from the first laminate 8), i.e., the portions not in contact with the liquid-repellent layer 7, the transfer layer 3 and adhesion layer 4 are transferred to the first laminate 8 and do not remain on the base layer 2. In other words, the base layer 2 peels off. Thus, the transfer sheet 1 enables selective transfer of the transfer layer to the object to be transferred. As a result, the liquid-repellent layer 7 is exposed, and the surface of the melamine decorative laminate 12 is formed by the exposed liquid-repellent layer 7, creating a design with a difference in gloss between the areas with and without the liquid-repellent layer 7. Next, the first laminate 8 after peeling is irradiated with ionizing radiation to cure the ionizing radiation-curable resin of the transfer layer 3, completing the melamine decorative laminate 12.

[0029] As described above, the transfer sheet 1 according to this embodiment allows for selective transfer of the transfer layer to the object to be transferred by including a chlorinated polyolefin resin in the transfer layer, thereby providing a transfer sheet 1 that can maintain the excellent design properties of the object to be transferred. Furthermore, in the transfer sheet 1, since the resin constituting the transfer layer 3 is an uncured ionizing radiation-curable resin, the flexibility of the transfer layer 3 can be improved during hot-press transfer, and film cracking of the transfer layer 3 due to hot-press transfer can be prevented. Furthermore, because the intralayer strength of the transfer layer 3 is weakened, when the substrate layer 2 is peeled off from the first laminate 8, the transfer layer 3 tears along the outer edge of the liquid-repellent layer 7 of the first laminate 8, preventing the transfer of the transfer layer 3 onto the liquid-repellent layer 7. This allows for selective transfer of the transfer layer 3, enabling gloss adjustment by the liquid-repellent layer 7.

[0030] Incidentally, if the transfer layer 3 contains an ionizing radiation-curable resin after curing, the intralayer strength of the transfer layer 3 is strong. As a result, when the substrate layer 2 is peeled from the first laminate 8, the transfer layer 3 does not break, and the transfer layer 3 is also transferred onto the liquid-repellent layer 7. This prevents selective transfer of the transfer layer 3, making gloss adjustment difficult. Furthermore, in the transfer sheet 1 according to this embodiment, the resin constituting the adhesion layer 4 is a thermosetting resin that does not contain components that exhibit liquid repellency. Therefore, for example, when manufacturing the melamine decorative laminate 12, by bringing the adhesion layer 4 into contact with the liquid-repellent layer 7, the adhesion layer 4 can absorb any remaining water-based melamine resin liquid on the liquid-repellent layer 7, thereby preventing whitening of the melamine decorative laminate 12. In addition, the transfer layer 3 can be appropriately transferred to areas on the surface of the first laminate 8 where the liquid-repellent layer 7 is absent.

[0031] Incidentally, if the adhesion layer 4 contains a thermosetting resin that exhibits liquid-repellent properties, then during the manufacturing of the melamine decorative laminate 12, any remaining water-based melamine resin liquid on the liquid-repellent layer 7 is not absorbed by the adhesion layer 4, the remaining liquid is not removed, and whitening occurs in the melamine decorative laminate 12. Furthermore, the transfer layer 3 is not properly transferred to areas on the surface of the first laminate 8 where the liquid-repellent layer 7 is absent. Furthermore, in the transfer sheet 1 according to this embodiment, the ionizing radiation-curable resin is at least one of an ultraviolet-curable resin and an electron beam-curable resin. Therefore, for example, when manufacturing the melamine decorative laminate 12, by irradiating the transfer layer 3 with ultraviolet light or an electron beam after heat transfer, it is possible to prevent cracking of the transfer layer 3 due to heat transfer while improving the strength of the melamine decorative laminate 12.

[0032] Furthermore, the manufacturing method for the melamine decorative laminate 12 according to this embodiment includes the steps of: immersing a first laminate 8 having a core layer 5 and a liquid-repellent layer 7 partially provided on one side 5a of the core layer 5 in an aqueous melamine resin solution; applying pressure and heat to a second laminate 9 formed by laminating a transfer sheet 1 on the liquid-repellent layer 7 side of the immersed first laminate 8 to cure the uncured aqueous melamine resin solution contained in the core layer 5; peeling the base layer 2 of the transfer sheet 1 from the first laminate 8 and transferring a part of the transfer layer 3 of the transfer sheet 1, which contains uncured ionizing radiation-curable resin and chlorinated polyolefin resin, to the first laminate 8; and irradiating the first laminate 8 with ionizing radiation to cure the ionizing radiation-curable resin of the transfer layer 3. Therefore, a melamine decorative laminate 12 with selectively adjusted gloss can be easily obtained. In addition, a melamine decorative laminate 12 with excellent ease of cleaning, scratch resistance and fingerprint resistance, and a pleasant tactile feel can be obtained.

[0033] (Effects of this embodiment) The transfer sheet 1 of this embodiment can achieve the following effects. (1) The device comprises a base layer 2, a transfer layer 3 provided on one side of the base layer 2, and an adhesive layer 4 provided on the side of the transfer layer 3 opposite to the base layer 2, wherein the resin constituting the transfer layer 3 is an uncured ionizing radiation-curable resin and a chlorinated polyolefin resin, and the resin constituting the adhesive layer 4 is a thermosetting resin that does not contain components that exhibit liquid repellency. This allows the transfer sheet 1 to selectively transfer the transfer layer 3 to the object to be transferred (e.g., the first laminate 8), thereby maintaining the excellent design properties of the object to be transferred.

[0034] (2) The content of chlorinated polyolefin resin in the transfer layer 3 is within the range of 0.1% by mass or more and 10% by mass or less relative to the ionizing radiation-curable resin. This makes it possible to suitably control the weight A of the peeling of the substrate layer 2 from the transfer layer 3. Therefore, selective transfer of the transfer layer 3 to the object to be transferred (e.g., the first laminate 8) can be reliably achieved, and the excellent design properties of the object to be transferred can be reliably maintained. (3) The chlorinated polyolefin resin in the transfer layer 3 is a chlorinated polypropylene resin. This reliably improves the adhesion between the transfer layer 3 and the substrate layer 2. Therefore, it becomes possible to more reliably achieve selective transfer of the transfer layer 3 to the object to be transferred (e.g., the first laminate 8), and to more reliably maintain the excellent design properties of the object to be transferred.

[0035] (4) At least one of the following finishes is applied to one of the surfaces of the base material layer 2 (the surface on which the transfer layer 3 is provided): mirror finish or matte finish. This makes it possible to impart various design features to the surface of the transfer layer 3. (5) The ionizing radiation-curable resin in the transfer layer 3 is at least one of an ultraviolet-curable resin and an electron beam-curable resin. This makes it possible to provide tack-free properties in the transfer layer 3, where the resin does not adhere after heat drying alone, and after-curing properties, which allow curing by irradiation with ultraviolet light or electron beams even after heat pressure transfer.

[0036] (Examples) Examples and comparative examples of the transfer sheet 1 according to the present invention are described below. However, the present invention is not limited to the following examples.

[0037] (Example 1) First, as the base layer 2, a roll of tissue paper was prepared, with polypropylene resin laminated to one side. The basis weight of the tissue paper was 40 g / m². 2 The polypropylene thickness was set to 16 μm. The surface gloss value of the raw material was set to 1.0 (measured using a HORIBA 60° gloss meter). Subsequently, a one-component UV-curable resin, which has tack-free properties achieved solely by heat drying, was applied to the polypropylene resin side of the base material layer 2 as the main component of the transfer layer coating liquid to form the transfer layer 3. The amount of UV-curable resin applied after drying was 6 g / m². 2The above coating solution was composed of 0.1% by mass of chlorinated polypropylene resin (chlorinated PP) added to the main component, an ultraviolet-curable resin. Subsequently, a urethane resin without silicone oil, which is a coating solution for the adhesion layer, was applied to one side of the transfer layer 3 (the side opposite to the substrate layer 2) to form the adhesion layer 4. The amount of urethane resin applied after drying was 2 g / m². 2 This was done to produce transfer sheet 1 of Example 1.

[0038] The coating liquid for the transfer layer (UV-curable resin with added chlorinated PP) and the coating liquid for the adhesion layer (urethane resin) were applied using a seven-color gravure printing press for decorative sheet manufacturing. The printing speed was 100 m / min. The drying conditions were as follows: each layer was dried at 100°C, and after all layers were coated, the resin was dried in two separate after-drying zones, each 5 m long, at 120°C and 180°C in succession to ensure thorough drying. This resulted in obtaining transfer sheet 1 according to Example 1. After drying, transfer sheet 1 was rolled up and stored.

[0039] Next, the first laminate 8 was immersed in an aqueous melamine resin solution, and the side of the first laminate 8 with the liquid-repellent layer 7, which was immersed in the aqueous melamine resin solution, was superimposed with the side of the prepared transfer sheet 1 with the adhesive layer 4 to form the second laminate 9. The first laminate 8 was constructed by providing a liquid-repellent layer 7 made of melamine resin and a pattern layer 6 (melamine resin overlay) made of aqueous ink on top of a phenol resin-impregnated paper which was the core layer 5. Next, the formed second laminate 9 was sandwiched between two mirror plates 10 and 11, and the second laminate 9 was subjected to pressure and heat (thermal transfer). The thermal transfer was performed using a hot press at a pressure of 100 kg / cm². 2 The process was carried out under conditions of a molding temperature of 160°C and a heating and pressurizing time of 10 minutes. Subsequently, the base layer 2 was peeled off from the first laminate 8, and then the peeled first laminate 8 was irradiated with ionizing radiation (ultraviolet light) to cure the radiation-curable resin of the transfer layer 3. This produced the melamine decorative laminate 12 of Example 1. In this configuration, the patterned layer 6 of the first laminate 8 is a wood grain pattern, and the liquid-repellent layer 7 is a vascular pattern.

[0040] (Example 2) In the coating solution for the transfer layer, 0.5% by mass of chlorinated polypropylene resin was added to the main component, an ultraviolet-curable resin. Otherwise, the procedure was the same as in Example 1 to obtain the transfer sheet 1 and melamine decorative laminate 12 of Example 2. (Example 3) In the coating solution for the transfer layer, 1% by mass of chlorinated polypropylene resin was added to the main component, an ultraviolet-curable resin. Otherwise, the procedure was the same as in Example 1 to obtain the transfer sheet 1 and melamine decorative laminate 12 of Example 3. (Example 4) In the coating solution for the transfer layer, 5% by mass of chlorinated polypropylene resin was added to the main component, an ultraviolet-curable resin. Otherwise, the procedure was the same as in Example 1 to obtain the transfer sheet 1 and melamine decorative laminate 12 of Example 4. (Example 5) In the coating solution for the transfer layer, 10% by mass of chlorinated polypropylene resin was added to the main component, an ultraviolet-curable resin. Otherwise, the procedure was the same as in Example 1 to obtain the transfer sheet 1 and melamine decorative laminate 12 of Example 5.

[0041] (Comparative Example 1) In the coating solution for the transfer layer, chlorinated polypropylene resin was not added to the main component, the UV-curable resin. Otherwise, the procedure was the same as in Example 1 to obtain the transfer sheet and melamine decorative laminate of Comparative Example 1.

[0042] <Performance Evaluation> The following performance evaluations were performed on the melamine decorative laminates 12 of Examples 1-5 and Comparative Example 1. (Design (Selective Reproduction) Evaluation) In the design aesthetics (selective transfer) evaluation, the design aesthetics of the melamine decorative laminate 12 was visually assessed. In particular, attention was paid to whether the transfer layer of the transfer sheet was transferred to areas in the first laminate 8 where it should not be transferred (the vascular pattern portion of the liquid-repellent layer 7). Ten judges participated, and the design aesthetics was evaluated based on the number of judges who visually determined that the transfer layer was transferred to the vascular pattern portion of the liquid-repellent layer 7 (i.e., the design aesthetics of the melamine decorative laminate 12 was low). Specifically, the number of judges who deemed the melamine decorative laminate 12 to have low design appeal based on the following criteria was divided into three levels: "○", "△", and "×", to evaluate the perceived design appeal. [Evaluation Criteria] 〇: 0 people determined that there was a transfer of the conduit pattern. △: 1 to 5 people determined that there was a transfer of the conduit pattern. ×: Six or more people determined that there was a transfer of the conduit pattern. Based on the evaluation criteria above, "〇" and "△" indicate a pass, and "×" indicates a fail.

[0043] (Design evaluation (prevention of whitening)) In the design aesthetic evaluation, the aesthetic appeal of the melamine decorative laminate 12 was visually assessed. Particular attention was paid to the whitening of the vascular pattern (the vascular pattern portion of the liquid-repellent layer 7). Ten judges were assigned to the evaluation, and the aesthetic appeal was assessed based on the number of judges who determined that no whitening of the vascular pattern occurred (high aesthetic appeal). Specifically, the number of judges who determined that no whitening of the vascular pattern of the melamine decorative laminate 12 occurred was divided into four levels: "◎", "〇", "△", and "×", according to the following criteria, and the aesthetic appeal was evaluated. [Evaluation Criteria] ◎: 10 people determined there was no whitening of the vascular pattern. ○: 7-9 people determined that there was no whitening of the vascular pattern. △: 1 to 6 people determined that there was no whitening of the vascular pattern. ×: 0 people determined there was no whitening of the vascular pattern. Based on the evaluation criteria above, "◎" and "〇" indicate a pass, while "△" and "×" indicate a fail.

[0044] (Evaluation of peelability) In the peelability evaluation, the weight (peelability) of the transfer sheet when peeling it off the first laminate 8 after heat pressure transfer using a hot press was evaluated sensorily in three stages: "○", "△", and "×", according to the following criteria. [Evaluation Criteria] ○: Light peelability △: Heavy peelability ×: Cannot be peeled off Based on the evaluation criteria above, "〇" and "△" indicate a pass, and "×" indicates a fail. Furthermore, "light peelability" indicates that the transfer sheet can be peeled off without applying force in the area where the liquid-repellent layer 7 is provided in the first laminate 8. Conversely, "heavy peelability" indicates that the transfer sheet can be peeled off by applying force in the area where the liquid-repellent layer 7 is provided.

[0045] The results of the above performance evaluation are shown in Table 1. In the evaluation results based on the above criteria, "〇" and "△" indicate a pass, and "×" indicates a fail.

[0046] [Table 1]

[0047] As shown in Table 1 above, the melamine decorative laminates 12 of Examples 1 to 5 all passed the "Design (Selective Transfer) Evaluation" ("○", "△"). In other words, it was confirmed that the transfer sheets of Examples 1 to 5 are capable of selective transfer of the transfer layer to the transfer target (first laminate 8) and can maintain the excellent design of the transfer target. Specifically, in Examples 1 to 4, the transfer layer was not transferred to the conduit pattern portion of the liquid-repellent layer 7, and selective transfer of the transfer layer to the transfer target was achieved, resulting in a passing (○) "Design (Selective Transfer) Evaluation". However, the transfer sheet of Example 5 had a chlorinated polypropylene content of (10% by mass), which is higher than that of the transfer sheets of Examples 1 to 4, resulting in a lower evaluation (△) compared to Examples 1 to 4. Furthermore, as shown in Table 1 above, the melamine decorative laminates 12 of Examples 1 to 5 all passed the "Releaseability Evaluation" ("○" or "△"). However, the transfer sheets of Examples 4 and 5 had a higher chlorinated polypropylene content in the transfer layer compared to the transfer sheets of Examples 1 to 3 (5% by mass or more), resulting in a lower "Releaseability Evaluation" rating (△) compared to Examples 1 to 3. Furthermore, the melamine decorative laminates in Examples 1-5 showed no whitening, exhibited selective gloss differences, and conveyed a sense of three-dimensionality and luster in the wood grain, resulting in a "◎" rating for "design (prevention of whitening) evaluation."

[0048] On the other hand, in Comparative Example 1, the melamine decorative laminate 12 did not contain chlorinated polypropylene resin in the transfer layer. As a result, the peeling weight when the substrate layer was peeled from the transfer layer was insufficient, and the transfer layer 3 was transferred to areas of the first laminate 8 that were not intended for transfer (the conduit pattern areas of the liquid-repellent layer 7). In other words, selective transfer of the transfer layer to the transfer target was not achieved, and the "design aesthetic evaluation" was rejected ("×").

[0049] Therefore, it was confirmed that, unlike the transfer sheet 1 of Comparative Example 1, the transfer sheet 1 of Examples 1 to 5 contains a chlorinated polyolefin resin in the transfer layer, enabling selective transfer of the transfer layer to the object to be transferred and maintaining the excellent design properties of the object to be transferred. Furthermore, it was confirmed that the transfer sheet 1 of Examples 1 to 5 prevents cracking of the transfer layer 3 due to heat pressure transfer because the ionizing radiation curable resin in the transfer layer is in an uncured and flexible state, and the thermosetting resin in the adhesion layer does not contain components that cause liquid repellency.

[0050] Furthermore, for example, the present invention can take the following configuration. (1) A base layer and A transfer layer provided on one side of the substrate layer, The transfer layer comprises an adhesion layer provided on the side of the transfer layer opposite to the substrate layer, The resin constituting the transfer layer is an uncured ionizing radiation-curable resin and a chlorinated polyolefin resin. The transfer sheet is characterized in that the resin constituting the adhesive layer is a thermosetting resin that does not contain any components that cause liquid repellency. (2) The content of the chlorinated polyolefin resin in the transfer layer is within the range of 0.1% by mass or more and 10% by mass or less relative to the ionizing radiation-curable resin. The transfer sheet described in (1) above, characterized in that it is a transfer sheet. (3) The chlorinated polyolefin resin is a chlorinated polypropylene resin. The transfer sheet according to (1) or (2) above, characterized in that (4) A portion or the entirety of one of the surfaces of the substrate layer is either mirror-finished or matte-finished. A transfer sheet according to any one of the above items (1) to (3), characterized in that (5) The ionizing radiation-curable resin is at least one of an ultraviolet-curable resin and an electron beam-curable resin. A transfer sheet according to any one of the above items (1) to (4), characterized in that it is the transfer sheet described above. (6) A method for manufacturing a melamine decorative laminate using a transfer sheet as described in any one of the above items (1) to (5), A first laminate having a core layer and a liquid-repellent layer partially provided on one side of the core layer is immersed in an aqueous melamine resin solution, and a second laminate formed by laminating the transfer sheet onto the liquid-repellent layer side of the immersed first laminate is subjected to pressure and heat to cure the uncured aqueous melamine resin solution contained in the core layer. A step of peeling the substrate layer of the transfer sheet from the first laminate and transferring a portion of the transfer layer of the transfer sheet, which contains the uncured ionizing radiation-curable resin and the chlorinated polyolefin resin, to the first laminate. A method for manufacturing a melamine decorative laminate, characterized by including a step of irradiating the first laminate with ionizing radiation to cure the ionizing radiation-curable resin of the transfer layer. [Explanation of Symbols]

[0051] 1...Transfer sheet, 2...Base layer, 3...Transfer layer, 4...Adhesion layer, 5...Base paper, 6...Pattern layer, 7...Liquid-repellent layer, 8...First laminate, 9...Second laminate, 10...Mirror plate, 11...Mirror plate, 12...Me Ramin decorative laminate

Claims

1. A base layer and A transfer layer provided on one side of the substrate layer, The transfer layer comprises an adhesion layer provided on the side of the transfer layer opposite to the substrate layer, The resin constituting the transfer layer is an uncured ionizing radiation-curable resin and a chlorinated polyolefin resin. The content of the chlorinated polyolefin resin in the transfer layer is within the range of 0.1% by mass or more and 10% by mass or less relative to the ionizing radiation-curable resin. The resin constituting the aforementioned adhesion layer is a thermosetting resin that does not contain any components that exhibit liquid-repellent properties. A transfer sheet characterized by the following features.

2. The content of the chlorinated polyolefin resin in the transfer layer is within the range of 0.1% by mass or more and 1% by mass or less relative to the ionizing radiation-curable resin. The transfer sheet according to feature 1.

3. The chlorinated polyolefin resin is a chlorinated polypropylene resin. The transfer sheet according to feature 2.

4. A portion or the entirety of one of the surfaces of the substrate layer is either mirror-finished or matte-finished. The transfer sheet according to feature 3.

5. The ionizing radiation-curable resin is at least one of an ultraviolet-curable resin and an electron beam-curable resin. The transfer sheet according to feature 4.

6. A method for manufacturing a melamine decorative laminate using a transfer sheet according to any one of claims 1 to 5, A first laminate having a core layer and a liquid-repellent layer partially provided on one side of the core layer is immersed in an aqueous melamine resin solution, and a second laminate formed by laminating the transfer sheet onto the liquid-repellent layer side of the immersed first laminate is subjected to pressure and heat to cure the uncured aqueous melamine resin solution contained in the core layer. A step of peeling the base layer of the transfer sheet from the first laminate and transferring a portion of the transfer layer of the transfer sheet, which contains the uncured ionizing radiation-curable resin and the chlorinated polyolefin resin, to the first laminate. A method for manufacturing a melamine decorative laminate, characterized by including a step of irradiating the first laminate with ionizing radiation to cure the ionizing radiation-curable resin of the transfer layer.

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