TW201504049A - Melamine decorative board and method of manufacturing melamine decorative board - Google Patents

Abstract

A melamine decorative board 100 is comprised of a laminated body in which a surface layer 11 whose first surface 111 becomes a mirror surface, an intermediate layer 13 and a core member layer 12 are laminated together in this order. The surface layer 11 is comprised of a surface layer material containing a surface layer base material, a melamine resin carried on a side of the first surface 111 of the surface layer base material and a thermoplastic resin carried on a side of a second surface 112 of the surface layer base material. The core member layer 12 is comprised of a core member layer material containing a glass cloth or a prepreg including a glass cloth as a base material thereof. The intermediate layer 13 is configured such that an average thickness thereof is larger than an arithmetic average roughness Ra1 of a surface of the core member layer 12 located on a side of the intermediate layer 13.

Description

Melamine decorative board and method for manufacturing melamine decorative board

The present invention relates to a method for producing a melamine decorative board and a melamine decorative board.

A decorative sheet of melamine resin is used in the surface layer of the melamine decorative board, and is used when a design such as a wood grain pattern is applied to a wall surface of a building, an inner wall surface of a vehicle such as an elevator or a train, a surface of a table or a bookcase, or the like. .

Further, in recent years, incombustible melamine decorative sheets composed of a surface layer using a melamine resin and a glass fiber base material have become mainstream.

As such a non-combustible melamine decorative sheet, a decorative sheet which can be easily bent is known (for example, see Patent Document 1).

The melamine decorative sheet described in Patent Document 1 has a small thickness and can be easily bent.

Moreover, the design surface of the melamine decorative board may be mirror-finished in order to highlight the high-grade feeling. However, since the surface layer of the melamine decorative sheet described in Patent Document 1 has a small thickness, even if mirror surface processing is performed, the surface layer is affected by the surface shape of the glass fiber base material, and it is difficult to make the design surface a perfect mirror surface.

[Previous Technical Literature]

[Patent Literature]

[Patent Document 1] Japanese Patent No. 5099206

An object of the present invention is to provide a method for producing a melamine decorative sheet which is excellent in nonflammability and bending workability, and which has a design surface to be mirror-finished and which can be easily produced.

The object as described above is achieved by the present invention of the following (1) to (12).

(1) A melamine decorative board comprising: a layered body having a surface layer, an intermediate layer and a core layer sequentially laminated; wherein the surface layer is composed of a surface layer material comprising a surface layer substrate, the surface The layer substrate carries a resin containing a melamine resin on the first surface side of the design surface, and carries a thermoplastic resin on the second surface side in contact with the intermediate layer, wherein the first surface of the surface layer is a mirror surface; The layer is composed of a core material layer made of a glass cloth or a prepreg containing a glass cloth as a base material; the intermediate layer is made of a resin for forming an intermediate layer, and an average thickness of the intermediate layer is larger than the above-mentioned core layer The arithmetic mean roughness Ra1 of the face on the intermediate layer side.

(2) The melamine decorative sheet according to the above (1), wherein the first surface of the surface layer has an arithmetic mean roughness Ra2 of 300 nm or less.

(3) The melamine decorative board according to the above (1) or (2), wherein the intermediate layer has an average thickness of 5 μm or more.

(4) The melamine decorative board according to any one of the above (1) to (3), In the above, the arithmetic mean roughness Ra1 is 0.1 to 10 μm.

(5) The melamine decorative board according to any one of the above (1) to (4), wherein the melamine decorative board has an average thickness of 0.4 mm or less.

(6) A method for producing a melamine decorative sheet, which is characterized in that the method for producing a melamine decorative sheet according to any one of the above (1) to (5) is characterized in that it has a step of preparing a surface layer material. a first layer, a first substrate of the second layer made of the resin for forming the intermediate layer, and a second substrate made of the core material layer; and the surface of the first substrate on the second layer side a step of arranging the second substrate; and a shield having the mirror-processed abutting surface disposed such that the abutting surface faces the surface of the first substrate on the first layer side And a step of disposing a substrate film having an elastic modulus of 140° C. of 1 to 50 GPa so as to face the second substrate; and heating the first substrate to at least the substrate and the substrate film The step of obtaining the melamine decorative sheet by thermocompression bonding the first base body and the second base body, and removing the protective sheet and the base material film from the melamine decorative sheet.

(7) The method for producing a melamine decorative sheet according to the above aspect, wherein the first layer is provided by supplying a resin varnish containing the melamine resin to the first surface side of the surface layer substrate, and A resin varnish having an average particle diameter smaller than the arithmetic mean roughness Ra1 and having the above-mentioned thermoplastic resin is supplied to the second surface side of the surface layer substrate.

(8) The method for producing a melamine decorative sheet according to the above (7), wherein the second layer is used to have an average particle diameter larger than a particle composed of the thermoplastic resin and smaller than the arithmetic mean roughness. Average particle size of Ra1, and the above intermediate layer A resin varnish formed of particles composed of a resin is formed.

(9) The method for producing a melamine decorative sheet according to any one of the above-mentioned (6), wherein the second layer is formed of a resin having an average particle diameter of 150 nm or more and formed of the intermediate layer. The resin varnish of the particles is formed.

(10) The method for producing a melamine decorative sheet according to any one of the above (6), wherein the base film has an average thickness of 0.1 to 1.0 mm.

(11) The method for producing a melamine decorative sheet according to any one of the above (6), wherein the base film is made of a thermoplastic resin having a softening temperature of 120 to 160 °C.

(12) The method for producing a melamine decorative sheet according to any one of the above (6), wherein the heating temperature during the thermocompression bonding is 130 to 150 ° C and the pressure is 2 to 8 MPa.

According to the present invention, it is possible to provide a melamine decorative sheet which is excellent in nonflammability and bending workability and which has a design surface to be mirror-finished.

Further, it is possible to provide a method for producing a melamine decorative sheet which can easily produce such a melamine decorative sheet.

10‧‧‧1st matrix

11‧‧‧ surface layer

11'‧‧‧1st floor

12, 14‧‧‧ core layer

12'‧‧‧2nd matrix

13‧‧‧Intermediate

13'‧‧‧2nd floor

15‧‧‧Protective layer

16‧‧‧Support layer

20‧‧‧Base film

30‧‧‧ Guard plate (mirror finish guard)

100‧‧‧melamine decorative board

111‧‧‧1st

112‧‧‧2nd

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a cross-sectional view showing an embodiment of a melamine decorative sheet of the present invention.

Fig. 2 is a flow chart showing an example of a method for producing a melamine decorative sheet of the present invention.

Fig. 3 is a conceptual view showing another example of the constitution of the melamine decorative sheet of the present invention.

Fig. 4 is a conceptual view showing another example of the constitution of the melamine decorative sheet of the present invention.

Hereinafter, the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.

Melamine Decorative Board

First, a preferred embodiment of the melamine decorative sheet of the present invention will be described.

The melamine decorative board of the present invention is attached to the wall surface of a building, the inner wall surface of a vehicle such as an elevator or a train, the surface of a furniture such as a table or a bookcase, and the like, whereby an aesthetic or high-grade feeling can be imparted to the surface. Further, the melamine decorative board of the present invention is incombustible.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a cross-sectional view showing an embodiment of a melamine decorative sheet of the present invention.

In the following description, the upper side in FIG. 1 is referred to as "upper", and the lower side in FIG. 1 is referred to as "lower".

As shown in FIG. 1, the melamine decorative board 100 is composed of a laminate in which a surface layer 11, an intermediate layer 13, and a core layer 12 are laminated. That is, the melamine decorative sheet 100 has a configuration in which the surface layer 11 and the core layer 12 are joined by the intermediate layer 13.

Hereinafter, each layer will be described in detail.

<1. Surface layer>

The surface layer 11 includes a first surface 111 (upper surface) which is a design surface, and a second surface 112 (lower surface) which is on the opposite side of the first surface 111 and which is in contact with the intermediate layer 13. The surface layer 11 is composed of a surface layer material including a surface layer substrate, a resin containing a melamine resin supported on the first surface 111 side of the surface layer substrate, and a surface supported on the surface layer substrate. Thermoplastic resin on the side of 112 sides. Further, the design surface (first surface 111) of the surface layer 11 is a mirror surface.

Furthermore, in the present specification, the term "surface layer substrate carrying resin" means State: The resin is attached to the surface of the surface layer substrate (carrier) or to the voids inside the surface layer substrate. After the surface layer material is formed in this state, the resin carried on the surface layer substrate exhibits its properties. Further, the resin may be unevenly distributed on the surface of the surface layer substrate and the inside of the surface layer substrate.

The surface layer base material is a sheet-like base material, and a resin containing a melamine resin is placed on the first surface 111 side, whereby a design surface is formed on the first surface 111 of the surface layer 11. The material of the surface layer substrate is not particularly limited. For example, various fiber base materials such as pulp, linter, synthetic fiber, and glass fiber can be used as the surface layer base material. Further, if necessary, a titanium oxide-containing decorative paper containing a pigment such as titanium oxide or the like can be used as the surface layer substrate.

The basis weight of the surface layer substrate is not particularly limited, but is preferably 40 to 150 g/m ² . When the basis weight is less than the above lower limit, the resin is broken during the resin impregnation step, or the obtained surface layer material (surface layer 11) is likely to be wrinkled. Therefore, it may be difficult to perform the immersion treatment (for example, coating treatment). Further, there is a possibility that it is difficult to adjust the amount of the resin which is carried on the first surface 111 side and the second surface 112 side of the surface layer substrate, respectively. On the other hand, when the basis weight exceeds the above upper limit value, the amount of the resin carried on the surface layer substrate may be uneven, the flexibility of the melamine decorative sheet 100 may be lowered, and the productivity of the melamine decorative sheet 100 may be produced. Falling, leading to higher costs.

The surface layer material is obtained by supporting a resin containing a melamine resin on the upper surface side (the first surface 111 side) of the surface layer substrate. Thereby, an appropriate surface hardness can be given to the first surface 111 (design surface) of the surface layer 11 which is the upper surface of the surface layer 11.

The melamine resin is not particularly limited, and for example, a polymer obtained by reacting melamine with formaldehyde under neutral or weak base conditions can be used.

Mohr ratio of formaldehyde to melamine (hereinafter, also referred to as "reaction" Moerby" is the value of (molar amount of formaldehyde) / (molar amount of melamine). The reaction molar ratio is not particularly limited, but is preferably 1.0 to 4.0, more preferably 1.0 to 2.0, still more preferably 1.1 to 1.8. A melamine resin obtained by reacting melamine with formaldehyde at the reaction molar ratio can be preferably used. When the reaction molar ratio is less than the above lower limit, the unreacted melamine may increase, the storage property of the resin may decrease, and the cost may increase. Moreover, when the reaction molar ratio exceeds the above upper limit, the flexibility of the resin after curing may be remarkably lowered. Further, a resin containing only one type of melamine resin can be used as the resin supported on the upper surface side of the surface layer substrate, and a resin containing two or more kinds of melamine resins having a reaction molar ratio or a weight average molecular weight can also be used. As the resin carried on the upper surface side of the surface layer substrate.

Further, a commercially available product such as melamine resin manufactured by Sumitomo Chemical Co., Ltd. can be used as the melamine resin.

The weight average molecular weight of the melamine resin is not particularly limited, but is preferably 200 to 500, more preferably 250 to 350. When the weight average molecular weight of the melamine resin is less than the above lower limit, the unreacted melamine contained in the resin may increase, and the storage stability of the resin may decrease. Further, when the weight average molecular weight of the melamine resin is more than the above upper limit, the impregnation property of the resin with respect to the substrate may be lowered. Further, the above weight average molecular weight can be measured, for example, by GPC (gel permeation chromatography, standard material: polystyrene conversion).

The amount of the melamine resin contained in the resin on the upper surface (first surface 111) side of the surface layer substrate is not particularly limited, but is preferably 80 to 100% by mass, more preferably 95 to 100% by mass. . When the amount of the melamine resin contained in the resin on the upper surface side of the surface layer substrate is less than the above lower limit, the hardness of the surface (first surface 111) of the surface layer 11 may be lowered or the surface may be resistant. Pollution will decline.

The method of supporting the resin containing the melamine resin on the upper surface side (the first surface 111 side) of the surface layer substrate is not particularly limited. As such a method, for example, a method such as a spray device, a shower device, a knife coater, or a Comma coater can be used to dissolve the resin in a solvent. After the resin varnish is applied to the surface layer substrate, it is dried by heating at a temperature of about 80 to 130 °C. Thereby, a surface layer substrate (hereinafter sometimes referred to as a "resin carrier substrate") having a resin supported on the upper surface side is obtained.

Further, in the resin-supporting substrate (for example, resin-impregnated paper) after heat drying, it is preferable that when the weight of the entire resin-carrying substrate is 100% by mass, 2 to 6% by mass of volatilization remains. Ingredients (solvent). Thereby, the handling of the resin-carrying substrate becomes easy. In the case where the melamine decorative sheet 100 is produced by using such a resin-supporting substrate, when it is subjected to heating and pressure treatment (heat molding), it is carried on the upper surface side (the first surface 111 side) of the surface layer substrate. The resin of the melamine resin-containing resin has improved fluidity. Therefore, the design appearance and surface gloss of the surface layer 11 are good. On the other hand, when the volatile component is less than 2% by mass, the resin is easily broken, so that it is difficult to carry out the treatment. Further, since the fluidity of the resin is lowered, the appearance of the surface layer 11 is hindered. Further, when the melamine decorative sheet 100 is produced using a resin having a volatile component of more than 6%, the warpage (sheet curl) of the melamine decorative sheet 100 is likely to increase due to the dry environment after molding. Further, when the volatile component is 7.5% or more, the volatile component affects the gloss transfer property of the appearance of the melamine decorative sheet 100.

The solvent for dissolving the resin containing the melamine resin (for preparing the resin varnish) is not particularly limited, and examples thereof include water and methanol. As such a solvent, water is particularly preferred. Moreover, it is also possible to form a group within a range that does not adversely affect the coatability of the resin varnish or the like. Use a poor solvent. The amount of the solid component (all components other than the solvent) contained in the resin varnish is not particularly limited, but is preferably 30 to 70% by mass, and more preferably 45 to 60% by mass based on the total of the resin varnish. Thereby, the impregnation property of a resin varnish to a surface layer base material can be improved.

The surface layer material is formed by supporting the thermoplastic resin on the side of the second surface 112 opposite to the side of the first surface 111 (design surface) of the surface layer substrate.

The thermoplastic resin to be carried on the surface layer base material may be in the form of particles, a block, or a combination of the particles and the block, but it is preferable to contain the thermoplastic resin in the form of particles. Further, the particulate thermoplastic resin (thermoplastic resin particles) is a thermoplastic resin (resin varnish) obtained by dispersing a thermoplastic resin in a solvent and being in an emulsion state, and is used as a raw material, and can be easily dried. And indeed obtained.

The thermoplastic resin particles have excellent adhesion properties to metals or various materials. Therefore, the thermoplastic resin particles are carried on the surface layer substrate with high adhesion strength. In particular, even if a stress such as bending is applied to the surface layer substrate to deform it, the thermoplastic resin is also difficult to peel off from the surface layer substrate due to the high adhesion strength. Further, since the thermoplastic resin particles carried on the surface layer substrate are in point contact with each other, the deformation of the surface layer substrate is surely followed. Therefore, the melamine decorative board 100 is imparted with flexibility. As a result, the bending workability of the melamine decorative sheet 100 can be improved.

The thermoplastic resin is not particularly limited, and examples thereof include various thermoplastics such as an acrylic resin, an amine ester resin, a vinyl acetate copolymer, an amine ester acrylic resin, a styrene butadiene rubber (SBR), and a nitrile rubber (NBR). Resin. Among them, the thermoplastic resin is preferably a thermoplastic resin containing an amine ester acrylic composite particle.

The urethane resin is particularly excellent in toughness, elasticity, and flexibility, and is excellent in transparency, durability, weather resistance, chemical resistance, and film-forming property of the acrylic resin. Therefore, when an amine ester acrylic composite resin is used as the thermoplastic resin, the thermoplastic resin supported on the surface layer substrate can have characteristics of both the above-described amine ester resin and acrylic resin.

According to the above, the thermoplastic resin to be carried on the second surface 112 side of the surface layer base material preferably contains the amine ester acrylic composite particles which are particles composed of the amine ester acrylic composite resin.

In the present specification, the amine ester acrylic composite particles are particles having a heterophase structure of an acrylic resin and an amine ester resin in a single particle. In the present specification, the term "heterophase structure" means a structure in which a plurality of phases including different kinds of resins are present in one particle. Examples of the structure include a core-shell structure, a partial structure, and an island-like structure.

In the urethane-acrylic composite particles, it is preferred that each of the particles has a core-shell structure in which an acrylic resin is used as a core and an amine ester resin is used as a shell. When the amine ester acrylic composite particles having the above-described core-shell structure are supported on a surface layer substrate, the surface profile is an amine ester resin. Therefore, the characteristics of both the amine ester resin and the acrylic resin can be obtained on the second surface 112 side of the surface layer base material, and the characteristics of the amine ester resin can be imparted to the outer surface.

Further, the state in which the urethane-acrylic acid composite particles are supported on the second surface 112 side of the surface layer substrate is not particularly limited. Such particles can be linearly arranged, for example, to form a linear structure, or to obtain other various alignment states. The particle structure and the particle arrangement state can be confirmed, for example, by a scanning electron microscope (SEM).

Further, as the thermoplastic resin, one of the above thermoplastic resins may be contained alone, or two or more different thermoplastic resins may be contained in combination.

Further, the thermoplastic resin contains, in addition to the resin particles of the above thermoplastic resin, In addition, a small amount of a tackifier, a penetration enhancer, an antifoaming agent, etc. may be contained as needed.

The average particle diameter of the thermoplastic resin particles is not particularly limited, but is preferably smaller than the arithmetic mean roughness Ra1 of the surface (upper surface) on the intermediate layer 13 side of the core material layer 12 to be described later. Further, the average particle diameter of the thermoplastic resin particles is preferably from 30 to 100 nm, more preferably from 60 to 90 nm.

When the average particle diameter of the thermoplastic resin particles satisfies the above conditions, the impregnation property of the thermoplastic resin particles when immersed between the fibers of the surface layer substrate is improved, and the thermoplastic resin particles can be further immersed in the interior of the surface layer substrate. . Therefore, it is possible to impart good flexibility to the surface layer 11. In addition, when the average particle diameter of the thermoplastic resin particles is within the above range, it is sufficiently smaller than the arithmetic mean roughness Ra1 of the surface of the core layer 12 on the intermediate layer 13 side, and therefore, the design appearance of the design surface of the surface layer 11 The surface gloss is further improved.

Further, the thermoplastic resin is preferably water-insoluble. Thereby, it is possible to prevent the thermoplastic resin from moving toward the first surface 111 side of the surface layer substrate and mixing with the melamine resin supported on the first surface 111 side. Therefore, it is possible to prevent damage to the surface properties of the melamine resin on the side of the first surface 111.

The method of supporting the thermoplastic resin on the second surface 112 side of the surface layer substrate is not particularly limited, and the same method as the above method in which the resin containing the melamine resin is supported on the first surface 111 side of the surface layer substrate can be used. .

In particular, when a thermoplastic emulsion resin (resin varnish) is used as a raw material, the following method or the like can be used: the thermoplastic emulsion resin is applied to the surface layer substrate by a well-known method, and dried by heating.

Further, the thermoplastic emulsion resin obtained by dispersing the amine ester acrylic composite resin in a solvent to be in an emulsion state is preferably an aqueous transparent type.

Further, the aqueous transparent thermoplastic emulsion resin is water-soluble, and the solid component (coating film) after moisture removal is water-insoluble, and has transparency to the extent that the color design of the substrate can be clearly recognized. Therefore, in the present specification, the aqueous transparent thermoplastic emulsion resin refers to an aqueous resin solution having such characteristics. By using such a water-based transparent thermoplastic emulsion resin as a raw material of the thermoplastic resin supported on the second surface 112 side of the surface layer substrate, it is possible to suppress the influence of the color tone of the design surface of the surface layer.

In addition, it is preferable that the resin-supporting substrate (for example, resin-impregnated paper) after heat-drying has a weight of 100% by mass of the entire resin-supporting substrate, and 2 to 6% by mass remains. Volatile ingredients. Thereby, the handling of the resin-carrying substrate becomes easy. In the case where the melamine decorative sheet 100 is produced by using such a resin-supporting substrate, when it is subjected to heating and pressure treatment (heat molding), it is carried on the upper surface side (the first surface 111 side) of the surface layer substrate. The resin of the melamine resin-containing resin has improved fluidity. Therefore, the melamine decorative panel 100 has a good design appearance and surface gloss.

The solvent for dissolving the thermoplastic resin (for modulating the thermoplastic emulsion resin) is not particularly limited, and examples thereof include water. Further, it is also possible to use a poor solvent as a solvent in a range that does not adversely affect coating properties and the like. The amount of the solid component (all components other than the solvent) contained in the resin is not particularly limited, but is preferably 25 to 60% by mass, and more preferably 30 to 45% by mass based on the total amount of the resin. Thereby, the impregnation property of a resin with respect to a surface layer base material can be improved.

Further, as described above, the design surface (first surface 111) of the surface layer 11 is a mirror surface, and the arithmetic mean roughness Ra2 is preferably 300 nm or less, more preferably 150 nm or less. Thereby, the first surface 111 of the surface layer 11 becomes smoother, so that the melamine loading can be further improved. The high quality of the plaque 100.

<2. Core material layer>

The core material layer 12 is bonded to the lower surface (second surface 112) side of the surface layer 11 through the intermediate layer 13.

The core material layer 12 is composed of a core material layer material containing a glass cloth or a prepreg, and the prepreg cloth contains a glass cloth as a substrate. Thereby, heat resistance, non-combustibility, rigidity, and the like can be imparted to the melamine decorative sheet 100.

Further, irregularities are formed on the upper surface of the core material layer 12. The unevenness of the core material layer 12 is buried in the intermediate layer 13, whereby the core material layer 12 and the intermediate layer 13 are firmly joined by the anchoring effect (and then). That is, the interlayer bonding strength between the core material layer 12 and the intermediate layer 13 can be improved. Thereby, it is possible to reliably prevent the core material layer 12 from being peeled off from the intermediate layer 13 when the melamine decorative sheet 100 is subjected to bending processing.

The arithmetic mean roughness Ra1 of the upper surface (surface on the intermediate layer 13 side) of the core material layer 12 is not particularly limited, but is preferably 0.1 to 10 μm, more preferably 1 to 7 μm. Thereby, the interlayer bonding strength between the core material layer 12 and the intermediate layer 13 can be further improved.

Moreover, examples of the glass constituting the glass cloth include E glass, C glass, A glass, S glass, D glass, NE glass, T glass, and H glass. Among them, T glass is preferred. T glass is a material having a relatively small coefficient of thermal expansion. Therefore, by using the T glass as a constituent material of the glass cloth, the thermal expansion coefficient of the glass cloth can be reduced.

The weight of the glass cloth is not particularly limited, but it is required to satisfy the non-combustibility requirements of Article 2, No. 9 of the Building Standards Law, that is, when it is not allowed to crack or penetrate after burning, the basis weight is 100 g/m ² or more. Preferably. Further, the upper limit of the weight is not particularly limited, but in consideration of material cost and workability, the basis weight is preferably 250 g/m ² or less.

The prepreg is not particularly limited, and for example, a resin composition containing a thermoplastic resin or a thermosetting resin can be immersed in the glass cloth.

The amount of the resin composition contained in the prepreg is not particularly limited as long as the interlayer adhesion strength with the intermediate layer 13 is sufficient to form the melamine decorative sheet 100. When the thermoplastic resin is used as the resin composition, the amount of the thermoplastic resin (solid content) contained in the prepreg is preferably 1% by mass or more and 20% by mass or less, more preferably 1% by mass or more. 10% by mass or less. Thereby, the interlayer adhesion strength between the intermediate layer 13 and the core material layer 12 can be further improved.

In the case where a thermosetting resin is used as the resin composition, the amount of the thermosetting resin (solid content) contained in the prepreg is preferably 1% by mass or more and 20% by mass or less, more preferably 2%. The mass% or more and 10% by mass or less. Thereby, the interlayer adhesion strength between the intermediate layer 13 and the core material layer 12 can be further improved.

The thermoplastic resin is not particularly limited, and examples thereof include an acrylic resin, an amine ester resin, an ethylene vinyl acetate resin, and a styrene butadiene rubber (SBR). Among them, an acrylic resin and/or an amine ester resin is preferably used as the thermoplastic resin.

The thermosetting resin is not particularly limited, and examples thereof include a phenol resin, an epoxy resin, a propylene oxide resin, a (meth) acrylate resin, an unsaturated polyester resin, a diallyl citrate resin, a urea resin, and a horse. Come to imine resin and so on. Among them, a phenol resin is preferably used as the thermosetting resin from the viewpoint of incombustibility, heat resistance, and adhesion. These resins can be used singly or in combination.

The prepreg can be produced by a method known in the art. For example, the resin varnish obtained by dissolving a resin composition in a solvent is immersed in the glass cloth, and then dried, whereby the prepreg can be obtained.

Further, the core material layer 12 may also be in contact with the intermediate layer 13 on the upper surface side to carry the thermoplastic resin. As such a thermoplastic resin, the same thermoplastic resin as that of the thermoplastic resin on the second surface 112 side of the surface layer substrate can be used. Moreover, when the thermoplastic resin contains thermoplastic resin particles, the adhesion strength between the core material layer 12 and the intermediate layer 13 can be further improved, and the melamine decorative sheet 100 can have high bending workability at normal temperature. The average particle diameter of the thermoplastic resin particles is not particularly limited. Further, the thermoplastic resin particles may be water-soluble or water-insoluble.

In addition, the thermoplastic resin that is placed on the surface side of the core material layer 12 that is in contact with the intermediate layer 13 is not required to impart flexibility to the core material layer 12, and does not hinder heat generation and gas harmfulness during combustion. There is no special limit.

The thickness of the core material layer 12 is preferably 100 μm or more. Thereby, the melamine decorative sheet 100 can be provided with sufficient heat resistance and incombustibility. Further, the upper limit of the thickness is not particularly limited. However, the greater the thickness, the greater the thickness and weight of the melamine decorative panel 100 and the higher the cost. Therefore, it is preferable to set the thickness of the core material layer 12 within the range allowed by the design of the final product (melamine decorative sheet 100), and the thickness of the core material layer 12 is more preferably 350 μm or less.

<3. Middle layer>

The intermediate layer 13 is a resin layer disposed between the surface layer 11 and the core material layer 12, the upper surface of which is in contact with the surface layer 11, and the lower surface thereof is in contact with the core material layer 12, thereby joining the surface layer 11 and the core material layer 12 . The intermediate layer 13 is a layer having a function of relaxing the influence of the surface shape (concavity and convexity) of the upper surface of the core material layer 12 on the surface layer 11.

Thus, the invention is characterized in that an intermediate layer 13 is provided between the surface layer 11 and the core material layer 12.

With such a feature, it is possible to reduce the influence of the surface shape (concavity and convexity) of the upper surface of the core material layer 12 derived from the glass cloth on the design surface (first surface 111) of the surface layer 11. Thereby, the smoothness of the design surface of the surface layer 11 can be improved. As a result, it is possible to provide the melamine decorative sheet 100 which is excellent in nonflammability and bending workability and has a high-grade feeling produced by mirror finishing.

Further, in the melamine decorative sheet 100, the average thickness of the intermediate layer 13 is larger than the arithmetic mean roughness Ra1 of the upper surface of the core layer 12. Thereby, it is possible to suppress irregularities on the upper surface of the intermediate layer 13 due to the unevenness of the upper surface of the core layer 12, and the smoothness of the upper surface of the intermediate layer 13 is improved. As a result, the design appearance and surface glossiness of the design surface of the surface layer 11 can be improved. Further, the average thickness of the intermediate layer 13 satisfies the above conditions, whereby the intermediate layer 13 functions as a buffer layer and absorbs the stress applied to the melamine decorative sheet 100. Therefore, it is possible to reliably prevent the core material layer 12 from being peeled off from the intermediate layer 13 when the melamine decorative sheet 100 is subjected to bending processing.

The intermediate layer 13 is made of a resin for forming an intermediate layer.

The resin for forming the intermediate layer is not particularly limited, but preferably contains resin particles. In addition, an emulsion resin (resin varnish) obtained by dispersing a resin in a solvent to obtain an emulsion state is used as a raw material, and the emulsion resin (resin varnish) is dried, whereby the resin particles can be easily and surely obtained. When the resin for forming the intermediate layer contains resin particles, the resin particles are buried in the concave portion of the unevenness of the core material layer 12. Thereby, the smoothness of the upper surface of the intermediate layer 13 is further improved. Thereby, the influence of the surface shape of the core material layer 12 derived from the glass cloth on the design surface (the first surface 111) of the surface layer 11 can be further reduced.

The resin particles are not particularly limited, and examples thereof include an acrylic resin, an amine ester resin, a vinyl acetate copolymer, an amine ester acrylic composite resin, and a styrene butadiene rubber (SBR). Particles of a thermoplastic resin such as nitrile rubber (NBR). Among them, particles of an acrylic resin are preferably used as the resin particles. Thereby, the surface layer 11 and the core material layer 12 can be joined more firmly, and the influence of the surface shape of the core material layer 12 derived from the glass cloth on the design surface (the first surface 111) of the surface layer 11 can be further reduced.

The average particle diameter of the above resin particles is not particularly limited. When the thermoplastic resin to be carried on the lower surface side of the surface layer 11 contains thermoplastic resin particles, the resin particles larger than the average particle diameter of the thermoplastic resin particles and smaller than the arithmetic mean roughness Ra1 are preferable. The resin particles of such a size are embedded in the concave and convex portions of the core material layer 12, and the upper surface of the intermediate layer 13 can be made smooth. Further, even if the surface (the upper surface) on the surface layer 11 side of the intermediate layer 13 is formed with minute irregularities, the thermoplastic resin particles of the thermoplastic resin having an average particle diameter smaller than the resin particles are buried in the unevenness. Concave. As a result, the first surface 111 (design surface) of the surface layer 11 can be made smoother, and the design appearance and surface glossiness of the design surface of the surface layer 11 can be further improved.

Specifically, the average particle diameter of the resin particles is preferably 150 nm or more and 0.75 × Ra 1 or less, more preferably 200 nm or more and 0.50 × Ra 1 or less. When the average particle diameter of the resin particles contained in the resin for forming the intermediate layer is within the above range, the first surface 111 (design surface) of the surface layer 11 can be made smoother according to the above-described actions and effects, and the design of the surface layer 11 can be achieved. The design appearance and surface gloss of the surface are further improved.

Further, it is possible to more reliably prevent the resin particles from entering the surface layer 11 or the core material layer 12, and it is possible to more reliably exhibit the function as the intermediate layer 13 as described above. On the other hand, when the average particle diameter of the resin particles is less than the above lower limit, the melamine decorative sheet 100 may be manufactured depending on the type of the surface layer base material constituting the surface layer 11 or the type of the glass cloth constituting the core material layer 12 . At the time, the resin particles are absorbed by the surface layer 11 or the core material layer 12, resulting in difficulty in forming the intermediate layer 13.

Further, a film made of a resin for forming an intermediate layer can also be used as the intermediate layer 13.

Such a film can be composed of a thermoplastic resin such as an acrylic resin, an amine ester resin, a polyolefin resin, or a polyester resin. Even in the case where such a film is used as the intermediate layer 13, the influence of the surface shape of the core material layer 12 derived from the glass cloth on the design surface (the first surface 111) of the surface layer 11 can be further reduced. Moreover, when such a film is used as the intermediate layer 13, the material (solvent or the like) or time for forming the intermediate layer 13 can be saved, and therefore, the manufacturing cost of the melamine decorative sheet 100 can be reduced.

The average thickness of the intermediate layer 13 is not particularly limited as long as it is larger than the arithmetic mean roughness Ra1 of the upper surface of the core layer 12, but is preferably 6 μm or more, and more preferably 10 to 50 μm. Thereby, the influence of the surface shape of the core material layer 12 derived from the glass cloth on the design surface (the first surface 111) of the surface layer 11 can be more effectively reduced. On the other hand, when the average thickness of the intermediate layer 13 is less than the above lower limit value, the surface shape of the core material layer 12 derived from the glass cloth may be derived from the design surface of the surface layer 11 depending on the value of the arithmetic mean roughness Ra1. The influence of one side 111) will increase. Further, when the average thickness of the intermediate layer 13 exceeds the above upper limit value, the amount of heat generated when the intermediate layer 13 is burned may increase, and the melamine decorative sheet 100 having the intermediate layer 13 may lose incombustibility.

The melamine decorative sheet 100 as described above can be bent so that the minimum bending radius at normal temperature (usually about 20 to 30 ° C) is 10 mmR or less, but the degree of bending processing (the minimum bending radius value) ) is not limited to this. The minimum bending radius R is a radius R of the smallest mold which can obtain 100% of good products even if the normal temperature bending process in one direction is repeatedly performed along the mold having the curved portion having the radius R, and no problem such as cracks occur. .

Further, the overall thickness of the melamine decorative sheet 100 is preferably 0.4 mm or less. Thereby, the melamine decorative board 100 can be bent more easily.

In the present embodiment, as a preferred example, the thermoplastic resin placed on the second surface 112 side of the surface layer substrate has a particle shape, but may not be in the form of particles. In other words, for example, when a thermoplastic emulsion resin (resin varnish) is used to carry it on the second surface 112 side of the surface layer substrate, the thermoplastic resin may not remain in a particulate form after the resin varnish is dried.

Further, in the present embodiment, as a preferred example, the intermediate layer forming resin constituting the intermediate layer 13 is described as being in the form of particles, but may not be in the form of particles. In other words, for example, when the intermediate layer 13 is formed using an emulsion resin (resin varnish), the resin for forming the intermediate layer may not remain in a particulate form after the resin varnish is dried.

"Manufacturing method of melamine decorative board"

Next, a method of manufacturing the above melamine decorative sheet will be described.

Fig. 2 is a flow chart showing an example of a method for producing a melamine decorative sheet of the present invention.

In the following description, the upper side in FIG. 2 is referred to as "upper", and the lower side in FIG. 2 is referred to as "lower".

First, the first layer 11' composed of the above surface layer material is formed. Further, the first layer 11' is a layer of the surface layer 11 described above.

The resin containing the melamine resin is carried on one side (the first surface side of the design surface) (the upper surface side) of the surface layer substrate, and the thermoplastic resin is carried on the other surface (the second surface 112 side) (the lower surface side). Thereby, the first layer 11' is formed. More specifically, it will contain the following tree The resin varnish is supplied to the first surface 111 side of the surface layer substrate, and the resin contains a melamine resin, and the resin varnish containing particles (thermoplastic resin particles) composed of a thermoplastic resin is supplied to the surface layer substrate. On the two sides 112 side, the first layer 11' is formed thereby.

Further, in the resin varnish used when the thermoplastic resin is carried on the second surface 112 side of the surface layer substrate, the average particle diameter of the thermoplastic resin particles contained in the resin varnish is preferably 30 to 100 nm. More preferably 60 to 90 nm. When the average particle diameter of the thermoplastic resin particles satisfies the above conditions, the impregnation property of the thermoplastic resin particles when immersed between the fibers of the surface layer substrate is improved, and the thermoplastic resin particles can be further immersed in the interior of the surface layer substrate. . Therefore, it is possible to impart good flexibility to the surface layer 11. In addition, when the average particle diameter of the thermoplastic resin particles is within the above range, it is sufficiently smaller than the arithmetic mean roughness Ra1 of the surface of the core layer 12 on the intermediate layer 13 side, and therefore, the design appearance of the design surface of the surface layer 11 The surface gloss is further improved.

Next, the resin for forming an intermediate layer is applied to the lower surface (the other surface) of the first layer 11', and the second layer 13' made of the resin for forming the intermediate layer is formed. More specifically, a resin varnish containing particles (resin particles) composed of a resin for forming an intermediate layer is supplied to the lower surface of the first layer 11' to form a second layer 13'. The second layer 13' is a layer of the above intermediate layer 13.

In the resin varnish used for forming the second layer 13', the average particle diameter of the resin particles contained in the resin varnish is preferably 150 nm or more, and more preferably 200 nm or more. When the average particle diameter of the resin particles contained in the resin for forming the intermediate layer is within the above range, the first surface 111 (design surface) of the surface layer 11 can be made smoother according to the above-described actions and effects, and the design of the surface layer 11 can be achieved. The design appearance and surface gloss of the surface are further improved. Further, it is possible to more reliably prevent the resin particles from entering the surface layer 11 or the core material layer 12, and it is possible to more reliably exhibit the function as the intermediate layer 13 as described above.

According to the above, the first substrate 10 having the first layer 11' made of the surface layer material and the second layer 13' made of the resin for forming the intermediate layer is obtained (see FIG. 2(a)).

Further, the second layer 13' may be formed while the thermoplastic resin is carried on the lower surface (the other surface) side of the first layer 11'. The particle diameter of the resin particles of the intermediate layer forming resin is larger than the particle diameter of the resin particles constituting the thermoplastic resin of the surface layer 11, and the resin particles of the intermediate layer forming resin are less likely to enter the surface layer 11. In other words, the resin particles of the intermediate layer forming resin are less likely to be carried on the surface layer substrate. Therefore, the thermoplastic resin can be carried on the lower surface (second surface 112) side of the surface layer substrate while forming the intermediate layer. Thereby, the drying step can be carried out at one time, so that the production steps can be simplified and the cost can be reduced.

Next, a second base 12' made of a core material is prepared. The second base 12' is a layer of the core material layer 12.

Next, the second base body 12' is disposed so as to face the lower surface (the surface on the second layer 13' side) of the first base 10 (see FIG. 2(b)).

Next, a base film 20 having an elastic modulus at 140 ° C of 1 to 50 GPa was prepared.

Further, two shields (mirror-completed shields) 30 having mirror-processed abutting faces are prepared.

Next, as shown in FIG. 2(c), two sets of the first base body 10 and the second base body 12' which are disposed opposite to each other are prepared, and the base material 20 is sandwiched between the second base bodies 12' of the laminated body. The way between them is configured. In other words, the second substrate 12' of each of the laminates is disposed on the side of the base film 20.

Further, as shown in FIG. 2(c), the two mirror-finished panels 30 are disposed such that the respective abutting faces face the first base 10 (the first layer 11') of each of the laminated bodies.

Then, while the first base 10 (the first layer 11') is heated by the mirror-finished shield 30, the mirror-finished shields 30 are brought closer to each other. Thereby, the first base body 10 and the second base body 12' are thermocompression-bonded by pressing the respective laminated bodies by the mirror-finished shield 30 and the base film 20. Thereby, two melamine decorative panels 100 are obtained.

According to the manufacturing method as described above, the melamine decorative sheet 100 having excellent non-combustibility and bending workability and having a mirror-finished design surface can be easily produced.

Moreover, when the base film 20 is provided on the side of the second base 12', it is possible to alleviate the force when the second base 12' presses the first base 10 to the mirror-finished panel 30 when the thermocompression bonding is performed. Thereby, the influence of the surface shape of the glass cloth constituting the second base body 12' on the surface of the first base body 10 (the design surface of the surface layer 11) can be further reduced. As a result, the design surface of the melamine decorative panel 100 can be made into a smoother mirror surface.

Further, the substrate film 20 has an elastic modulus at 140 ° C of 1 to 50 GPa, preferably 15 to 40 GPa. Thereby, the influence of the surface shape of the glass cloth constituting the second base body 12' on the surface of the first base body 10 (the design surface of the surface layer 11) can be further reduced.

The material constituting the base film 20 is not particularly limited as long as it satisfies the above characteristics, but is preferably composed of a thermoplastic resin, and more preferably a thermoplastic resin having a softening temperature of 120 to 160 °C. Thereby, when the thermocompression bonding is performed, the influence of the surface shape of the glass cloth constituting the second base body 12' on the surface of the first base body 10 (the design surface of the surface layer 11) can be further reduced.

Further, the average thickness of the base film 20 is preferably from 0.1 to 1.0 mm, more preferably from 0.1 to 0.5 mm. Thereby, the influence of the surface shape of the glass cloth constituting the second base body 12' on the surface of the first base body 10 (the design surface of the surface layer 11) can be further reduced.

Further, a plurality of substrate films 20 may be used as needed.

Further, the conditions for the heat and pressure forming (thermocompression bonding) of the melamine decorative sheet 100 are not particularly limited, but it is preferably heated and pressed at a heating temperature of 130 to 150 ° C and a pressure of 2 to 8 MPa (hot pressing). Connect). Moreover, the thermocompression bonding time is preferably from 10 to 60 minutes. Thereby, the influence of the surface shape of the glass cloth constituting the second base body 12' on the surface of the first base body 10 (the design surface of the surface layer 11) can be further reduced.

Further, when the melamine decorative sheet 100 is thermocompression bonded, the method described below can be used in addition to the method of heating and pressurizing the first base 10 by the mirror finish guard 30. For example, it is possible to eject hot air or laser irradiation to each of the laminated bodies, and press the respective laminated bodies by the mirror finish guard 30, thereby obtaining the melamine decorative board 100.

Further, if necessary, the release film may be sandwiched between the base film 20 and the second substrate 12'. As the release film, a well-known release film can be used.

Although the preferred embodiment of the melamine decorative board of the present invention has been described above, the present invention is not limited thereto.

For example, the melamine decorative sheet of the present invention is not limited to the form of the melamine decorative sheet 100 shown in FIG. For example, when it is desired to increase the mechanical strength of the melamine decorative sheet or the like, as shown in FIG. 3, another core material composed of another core material layer material may be laminated on the lower side of the core material layer. In other words, two core material layers may be laminated to form a four-layer structure of the surface layer 11, the intermediate layer 13, the core material layer 12, and the core material layer 14. Further, it may have other layers than the surface layer, the intermediate layer, and the core material layer. For example, as shown in FIG. 4, the outermost layer on the design surface side (upper side in FIG. 4) may have a protective layer 15, or a core. The outermost layer of the material layer side (the lower side in FIG. 4) has a support layer 16.

The protective layer 15 is not particularly limited, and for example, the melamine resin is separately impregnated to a paper substrate having a basis weight of 10 to 50 g/m ² , or the following resin composition is impregnated to a paper substrate having a basis weight of 10 to 50 g/m ² . The protective layer 15 is obtained by drying, and the resin composition is a resin composition obtained by containing an inorganic filler selected from the group consisting of aluminum hydroxide, magnesium hydroxide or cerium oxide in the melamine resin.

The support layer 16 is not particularly limited, and for example, a prepreg or a metal foil can be used as the same substrate as the surface layer substrate, and the prepreg can be supported on the upper side (first surface side) of the surface layer or The resin on the lower side (the second surface side) is immersed in a glass cloth or the like.

Further, in the above embodiment, a method of simultaneously producing two melamine decorative sheets is described as a manufacturing method. However, the present invention is not limited thereto, and a method of producing a melamine decorative sheet one by one may be employed.

[Examples]

Hereinafter, the present invention will be described in detail based on examples and comparative examples, but the present invention is not limited thereto.

1. Manufacture of melamine decorative board

(Example 1)

A titanium oxide-containing decorative paper (manufactured by Dainippon Printing Co., Ltd.) having a basis weight of 80 g/m ^{2 was} prepared as a surface layer substrate.

Next, an amine ester acrylic resin composite emulsion (manufactured by Central Chemical Industry Co., Ltd., trade name "SU-100", average particle diameter: 84 nm, dispersion medium: water) having a solid content of 40 g/m ² was applied to the above-mentioned content. One surface side (second surface side) of the titanium oxide decorative paper.

Next, a melamine resin having a solid content of 50 g/m ² (reaction molar ratio of 1.4 and a resin solid content of 50% by mass) was applied to the other surface side of the titanium oxide-containing decorative paper (first surface side (design surface) side)).

Then, the above-mentioned amine ester acrylic composite resin emulsion and melamine resin were dried for 90 seconds by a hot air dryer at 120 °C. The urethane-acrylic composite particles were supported on the second surface side of the titanium oxide-containing decorative paper, and the melamine resin was carried on the first surface side (design surface side) of the titanium oxide decorative paper, and the resin ratio was 53%, and the volatile component ratio was 53%. It is the first layer of 3%.

Further, the melamine resin is synthesized by a method in which a raw material melamine and a formaldehyde liquid are prepared (charged) in a specific mixing ratio in a reaction container, and after adding a catalyst, the temperature is raised to a boiling point to carry out a reflux reaction. Then, after confirming that the melamine has been dissolved, when the reaction end point is reached, the resin solid content is adjusted by dehydration treatment and cooled.

Next, an acrylic resin emulsion (manufactured by ZEON Co., Ltd., trade name "Nipol LX-851E", average particle diameter: 200 nm, dispersion medium: water) having a solid content of 20 g/m ² was applied to the above first layer. The second side.

Then, it was dried by a hot air dryer at 120 ° C for 90 seconds to form a second layer (intermediate layer). Thereby, the first substrate having the first layer and the second layer and having a resin ratio of 58% and a volatile component ratio of 4% was obtained.

A glass cloth having a basis weight of 104 g/m ² (manufactured by Taiwan Nanya Corporation, trade name "Nanya-2116") was placed as a second substrate (core material layer) on the second surface side of the obtained first substrate. A laminate of the first substrate and the second substrate is formed. Further, the above steps were repeated to form another laminate in which the first substrate and the second substrate were superposed, and two sets of laminates were prepared.

Next, prepare two base film (manufactured by Sumitomo Bakelite), trade name "CEL E911B", thickness: 0.12mm, softening temperature: 140 °C) and two pieces. Release film (manufactured by Toray Co., Ltd., trade name "TORAYFAN SRP").

After the two release films are provided so as to sandwich the two base film, the release film and the base film are placed on the second substrate of the laminate in a manner of sandwiching the release film and the base film. between. Next, two mirror-finished shields having a mirror-finished abutting surface are disposed so that the respective abutting faces are opposed to the first base of each of the laminated bodies (measured by a gloss meter as a stainless steel plate) A mirror-finished stainless steel plate having a measured value of 300 or more is formed, and the laminated body and the substrate film are sandwiched.

In this state, the mirror-finished panels are brought close to each other (the mirror surface is completed close to the substrate film), and subjected to hot press forming (thermocompression bonding) at 140 ° C and 8 MPa for 40 minutes to obtain a thickness of 0.3mm melamine decorative board.

(Example 2)

In the formation of the second layer, an acrylic resin emulsion having a solid content of 10 g/m ² was applied to the second surface side of the first layer.

Further, a prepreg formed in the following manner was used as the second base material (core material layer). First, an amine ester acrylic resin composite emulsion (manufactured by Central Chemical Industry Co., Ltd., trade name "SU-100", average particle diameter: 84 nm, dispersion medium: water) having a solid content of 2 g/m ² was applied to the basis weight. It is a glass cloth of 104 g/m ² (manufactured by Taiwan Nanya Corporation, trade name "Nanya-2116"). Then, it was dried by a hot air dryer at 120 ° C for 150 seconds to prepare a prepreg (second substrate) having a resin ratio of 2% and a volatile component ratio of 3%.

A melamine decorative board having a thickness of 0.3 mm was obtained in the same manner as in the above Example 1 except the above.

(Example 3)

In the formation of the second layer, an acrylic resin emulsion having a solid content of 5 g/m ² was applied to the second surface side of the first layer.

A melamine decorative board having a thickness of 0.3 mm was obtained in the same manner as in the above Example 1 except the above.

(Example 4)

The first substrate having the first layer and the second layer is formed as follows.

A mixed liquid having a solid content of 50 g/m ² was applied to one surface side (second surface side) of a titanium oxide decorative paper (manufactured by Dainippon Printing Co., Ltd.) having a basis weight of 80 g/m ² , and the mixture was 100:30 solid content by weight, mixed with an amine ester acrylic resin emulsion (manufactured by Central Chemical Industry Co., Ltd., trade name "SU-100", average particle size: 84 nm, dispersing medium: water), and acrylic resin Emulsion (manufactured by Japan ZEON Co., Ltd., trade name "Nipol LX-851E", average particle diameter: 200 nm, dispersion medium: water).

Next, a melamine resin having a solid content of 50 g/m ² (reaction molar ratio of 1.4 and a resin solid content of 50% by mass) was applied to the other surface side of the titanium oxide-containing decorative paper (first surface side (design surface) side)).

Then, the mixture and the melamine resin were dried for 90 seconds by a hot air dryer at 120 °C. In this manner, an intermediate layer containing acrylic resin particles is formed on the second surface side of the first layer while forming the first layer, and the first substrate is obtained, and the first layer is carried on the second surface side of the titanium oxide-containing decorative paper. The urethane-acrylic composite particles are loaded with a melamine resin on the first surface side (design side) of the titanium oxide-containing decorative paper. Further, the first substrate had a resin ratio of 58% and a volatile component ratio of 4%.

A melamine decorative board having a thickness of 0.3 mm was obtained in the same manner as in the above Example 1 except the above.

(Example 5)

First, an acrylic film (manufactured by KANEKA, trade name "SANDUREN SD001NAT") was prepared.

Next, the first substrate was obtained in the same manner as in Example 1 except that the intermediate layer was not formed during the formation of the first substrate. Further, a second substrate was obtained in the same manner as in the above Example 1.

The acrylic film and the obtained second substrate are sequentially superposed on the second surface side of the obtained first substrate, and a laminate in which an acrylic film is interposed between the first substrate and the second substrate is formed. A melamine decorative board having a thickness of 0.35 mm was obtained in the same manner as in Example 1 except that the laminate was used.

(Comparative example)

A titanium oxide-containing decorative paper (manufactured by Dainippon Printing Co., Ltd.) having a basis weight of 80 g/m ^{2 was} prepared as a surface layer substrate.

Next, an amine ester acrylic acid composite particle emulsion having a solid content of 40 g/m ² (manufactured by Central Chemical Industry Co., Ltd., trade name "SU-100", average particle diameter: 84 nm, dispersion medium: water) was applied to the above-mentioned content. One surface side (second surface side) of the titanium oxide decorative paper.

Next, a melamine resin having a solid content of 50 g/m ² (reaction molar ratio of 1.4 and a resin solid content of 50% by mass) was applied to the other surface side of the titanium oxide-containing decorative paper (first surface side (design surface) side)).

Then, the amine ester acrylic acid composite particle emulsion and the melamine resin were dried by a hot air dryer at 120 ° C for 90 seconds to obtain a surface layer material (first layer) having a resin ratio of 53% and a volatile component ratio of 3%.

Furthermore, the above melamine resin is synthesized by the following method, which means In the reaction vessel, the raw material melamine and the formaldehyde liquid are prepared (charged) at a specific mixing ratio, and after adding a catalyst, the temperature is raised to the boiling point to carry out a reflux reaction. Then, after confirming that the melamine has been dissolved, when the reaction end point is reached, the resin solid content is adjusted by dehydration treatment and cooled.

A glass cloth having a basis weight of 104 g/m ² (manufactured by Taiwan Nanya Corporation, trade name "Nanya-2116") was placed as a core material layer and superposed on the second surface side of the obtained first layer to obtain a laminated body. The laminate was subjected to heat and pressure molding at 140 ° C and 8 MPa for 40 minutes to obtain a melamine decorative sheet having a thickness of 0.3 mm.

The constituent materials and the like of each layer of the melamine decorative sheets of the respective examples and comparative examples are shown in Table 1.

2. Test method

The following evaluations were performed on the melamine decorative sheets obtained in the above respective examples and comparative examples.

(1) Non-combustibility test

According to the business standard of the Japan Buildings Comprehensive Testing Institute, "Fracture resistance test, evaluation business method book" 4.10 Non-combustible performance test, evaluation method "(2) ii) 4.10.2 heat test, evaluation method and 4.10.3 Implementation of gas hazard test evaluation method".

In the above-mentioned items of the above-mentioned business standard "anti-fire resistance performance test and evaluation business method book", a performance evaluation method relating to the certification based on the provisions of Article 2, No. 9 (non-combustible materials) of the Building Standard Law is described.

(2) Boiling resistance test

The test was carried out in accordance with the method of boiling resistance test according to JIS K6902, and it was confirmed whether or not the test piece after immersion in boiling water for 2 hours was swelled or peeled off between layers.

(3) Pollution resistance test

The surface of the sample was confirmed to have any residual contamination material by following the method of the contamination resistance test of JIS K6902.

(4) Bending formability test

According to the bending formability test (A method) of JIS K6902, external bending and inner bending molding were performed at 10 mmR at room temperature, and it was confirmed whether or not the surface of the decorative sheet was cracked.

(5) Surface hardness (pencil hardness) test

Evaluation was performed by following the pencil hardness test of JIS K5600.

(6) Arithmetic mean roughness

Optical interference type surface shape roughness measuring device (manufactured by Veeco, trade name) "Wyko NT1100"), the arithmetic mean roughness Ra2 of the design surface of the melamine decorative sheet of each of the examples and the comparative examples was measured.

The above results are shown together in Table 1. In addition, in the core material layer of each of the examples and the comparative examples, the arithmetic mean roughness Ra1 of the surface on the intermediate layer side refers to the surface on the first surface side of the core material layer (second substrate). The arithmetic mean roughness Ra1 of the (surface on the intermediate layer side) is measured by the apparatus used in the above (6).

According to Table 1, the melamine decorative board of the present invention exhibits good bending workability and incombustibility, and has a good mirror surface. On the other hand, in the comparative example, a good mirror surface could not be formed.

[Industrial availability]

According to the present invention, it is possible to provide a melamine decorative sheet which is excellent in nonflammability and bending workability and which has a design surface to be mirror-finished. Further, it is possible to provide a method for producing a melamine decorative sheet which can easily produce such a melamine decorative sheet. Therefore, the present invention has industrial applicability.

11‧‧‧ surface layer

12‧‧‧ core layer

13‧‧‧Intermediate

100‧‧‧melamine decorative board

111‧‧‧1st

112‧‧‧2nd

Claims (12)

A melamine decorative board comprising a layered body having a surface layer, an intermediate layer and a core layer laminated thereon; wherein the surface layer has a first surface which is a first surface of the design surface, that is, a mirror surface, and the first surface a second surface opposite to the first surface, that is, a second surface in contact with the intermediate layer, wherein the surface layer is made of a surface layer material including a surface layer substrate and the first layer supported on the surface layer substrate a resin containing a melamine resin on the surface side and a thermoplastic resin supported on the second surface side of the surface layer substrate; wherein the core material layer is composed of a prepreg comprising glass cloth or a substrate comprising glass cloth as a substrate The core layer material is composed of the intermediate layer forming resin, and the intermediate layer has an average thickness larger than the arithmetic mean roughness Ra1 of the surface of the core layer on the intermediate layer side. The melamine decorative sheet according to the first aspect of the invention, wherein the first surface of the surface layer has an arithmetic mean roughness Ra2 of 300 nm or less. The melamine decorative board according to item 1, wherein the intermediate layer has an average thickness of 5 μm or more. The melamine decorative board according to item 1, wherein the arithmetic mean roughness Ra1 is 0.1 to 10 μm. For example, the melamine decorative board of the first aspect of the patent application, wherein the melamine decorative board has an average thickness of 0.4 mm or less. The invention relates to a method for manufacturing a melamine decorative board, which is a method for manufacturing a melamine decorative board according to claim 1 of the patent application, which has the following steps: a step of preparing a first substrate having a first layer made of the surface layer material and a second substrate made of a resin for forming the intermediate layer, and a second substrate made of the core material layer; and the second substrate a step of arranging the surface of the first substrate opposite to the surface of the second layer, and providing the shield having the mirror-finished contact surface to form the contact surface and the first substrate a surface of the first layer is disposed so as to face the substrate, and a substrate film having an elastic modulus of 140 to 150 GPa is disposed so as to face the second substrate; and at least the first substrate is heated. a step of obtaining the melamine decorative sheet by thermocompression bonding the first substrate and the second substrate with the protective layer and the base film, and the protective plate and the glazed decorative sheet from the melamine decorative sheet The step of removing the substrate film. The method for producing a melamine decorative sheet according to the sixth aspect of the invention, wherein the first layer is provided by supplying a resin varnish containing the melamine resin to the first surface side of the surface layer substrate, and containing A resin varnish having an average particle diameter smaller than the arithmetic mean roughness Ra1 and having the above-mentioned thermoplastic resin is supplied to the second surface side of the surface layer substrate. The method for producing a melamine decorative sheet according to claim 7, wherein the second layer is used to have an average particle diameter larger than a particle composed of the thermoplastic resin and smaller than the arithmetic mean roughness Ra1. The average particle diameter is formed of a resin varnish of particles composed of the above-mentioned intermediate layer forming resin. The method for producing a melamine decorative sheet according to claim 6, wherein the second layer is made of an intermediate layer having an average particle diameter of 150 nm or more. A resin varnish formed of particles composed of a resin is formed. The method for producing a melamine decorative sheet according to claim 6, wherein the base film has an average thickness of 0.1 to 1.0 mm. The method for producing a melamine decorative sheet according to claim 6, wherein the base film is made of a thermoplastic resin having a softening temperature of 120 to 160 °C. The method for producing a melamine decorative board according to the sixth aspect of the invention, wherein the heating temperature during the thermocompression bonding is 130 to 150 ° C, and the pressure is 2 to 8 MPa.