JP2011230364A - Metal plate covered with designed lamination sheet, method of producing the same, and unit bath member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metal plate covered with designed lamination sheet which has an internal embossing constitution which can view an internal embossing design through a transparent surface layer having satisfactory smoothness and having an emboss design with a depth feeling and a stereoscopic effect, and has a folding working property as the metal plate covered with designed lamination sheet, to provide a method of producing the metal plate covered with designed lamination sheet and to provide a unit bath member provided with the metal plate covered with designed lamination sheet.SOLUTION: The metal plate covered with designed lamination sheet is configured by laminating: a sheet 110 (A layer) having a rugged design by means of embossing on the surface thereof; a layer 121 (B-1 layer) made of a composition including an ultraviolet curable adhesive; a transparent biaxially stretched polyester sheet layer 131 (C-1 layer); a layer 122 (B-2 layer) made of a composition including the ultraviolet curable adhesive; and a transparent biaxially stretched polyester sheet layer 132 (C-2 layer), in this order on a metal plate, and has mirror-surface glossiness (Gd value) of C-2 layer, of 0.8 or more.

Description

  The present invention relates to a designable laminated sheet-coated metal plate used for architectural interior materials and the like, a method for producing the designable laminated sheet-coated metal plate, and a unit bus member using the designable laminated sheet-coated metal plate.

  Conventionally, as a design resin-coated metal plate used for a building interior material, a so-called mirror surface design type and an emboss design type have been used. As a type called a mirror surface design, a printed pattern is imparted on a sheet of soft polyvinyl chloride (hereinafter, may be abbreviated as “PVC”) colored by the addition of a pigment, and further on the sheet. The thing of the structure which coat | covered the resin film with transparency and favorable smoothness was used. In addition, as a type called an embossed design, a colored soft PVC sheet and a transparent soft PVC sheet are heated on the surface of a single layer of a colored soft PVC sheet or in the middle through a printed pattern. In general, a laminated sheet having an embossed surface on the transparent layer side is generally used.

  However, in recent years, the design resin-coated metal plate used for building interior materials is required to have better design properties, and as a configuration capable of obtaining a sense of depth, a three-dimensional effect, etc., transparent, or There is an increasing demand for a design-coated resin-coated metal plate in which a concavo-convex pattern (embossed pattern) existing inside can be visually recognized through a surface layer having a translucent and smooth surface. Called "composition" etc.).

As for the laminated sheet having an internal embossed structure, as disclosed in Patent Document 1, there is a method in which a transparent thermoplastic resin is extrusion coated on the uneven surface of a colored soft PVC sheet having an embossed surface, or a transparent PVC paste is coated. Proposed.
Further, Patent Document 2 discloses a laminated sheet having an internal embossing structure by, for example, filling an ultraviolet curable adhesive between the uneven surface of a colored soft PVC sheet embossed and printed on the surface and a transparent surface layer. It has been proposed to get

  However, as disclosed in Patent Document 1, in the former method, a transparent molten thermoplastic resin is extruded and coated, or a PVC paste is coated. There is a possibility that the uneven design of the emboss applied to the surface may cause the emboss return by heating from the molten resin. In the latter case, the embossed shape may become unclear because the base material layer also swells and softens due to the action of the coated PVC paste. In addition, regarding the smoothness of the outermost surface of the laminated sheet, in the case of batch processing in which heating and pressurizing treatment is performed for a certain time with a press using a mirror surface press plate, an extremely smooth surface can be obtained. There is a problem that productivity becomes worse. It was difficult to obtain a sufficiently smooth surface by momentary pressing with a continuous mirror roll with good productivity.

A laminated sheet having an internal embossed structure using an ultraviolet curable adhesive for adhesion lamination for adhering a transparent sheet of a surface layer and a sheet having an uneven design by embossing (hereinafter sometimes referred to as “embossed design”), or Regarding the production method, not only Patent Document 2 but also many known literatures can be seen, and it can be said that it is one standard as the construction and production method of a laminated sheet having an internal embossed structure. In these, it is common to use a biaxially stretched polyethylene terephthalate (PET) sheet as the transparent sheet of the surface layer. Compared with solvent-coated thermosetting adhesives, UV curable adhesives have less thinness of the coating film due to solvent volatilization. Therefore, UV curable adhesives are used on colored sheets with embossed designs via UV curable adhesives. When a surface transparent sheet is provided, it is easy to obtain a smoother surface. In addition, UV curable adhesives are easier to adjust physical properties before and after curing the adhesive, and a series of coating and curing processes are simpler than solventless thermosetting adhesives. It also has the merit of For this reason, it is considered that the use of an ultraviolet curable adhesive has been generalized for laminating a transparent sheet having a surface layer and a sheet having an embossed design.
Thus, although it is an ultraviolet curable adhesive considered to be suitable for obtaining a laminated sheet having an internal emboss structure, it is inevitable that volume shrinkage occurs during curing. As a result, the portion corresponding to the valley of the embossed design of the sheet having the embossed design has a relatively large amount of shrinkage in the thickness direction because the UV curable adhesive is applied relatively thickly, and the embossed design has In the corresponding portion, the ultraviolet curable adhesive is applied relatively thin, so that the amount of shrinkage in the thickness direction is relatively small. Therefore, when a UV curable adhesive is applied to a sheet having a relatively deep embossed design, the embossed design is reflected on the surface of the surface layer as a difference in shrinkage in the thickness direction of the UV curable adhesive, As a result, the surface of the surface layer sheet was roughened in a similar shape to the embossed design of the base, and it was difficult to obtain a laminated sheet having an internal embossed structure having a surface with good smoothness. In addition, these known documents do not show how to solve the problem of difference in shrinkage in the thickness direction when the ultraviolet curable adhesive is cured.

If an extremely thick transparent stretched PET resin sheet having a thickness exceeding 300 μm is used as a surface layer sheet as in Patent Document 3, the effect of the difference in shrinkage depending on the location of the UV curable adhesive may not be reflected on the surface. There is. Alternatively, if a much thicker UV curable adhesive is applied compared to the difference in height between the valleys and peaks of the embossed design, the shrinkage in the thickness direction at these positions is substantially the same. As a result, there is a possibility that the surface of the surface layer sheet can be made relatively smooth.
However, these methods form a plate-like body rather than a laminated sheet, which hinders winding of a long product, and is not suitable as a design laminated sheet for covering a metal plate. Moreover, it is difficult to obtain secondary workability such as bending workability even for a design-use laminated sheet-coated metal plate obtained by laminating such a laminate sheet.

  Furthermore, in the state of the designable laminated sheet, even if a relatively smooth surface is obtained, after the designable laminated sheet is heat laminated to the metal plate in order to obtain a designable laminated sheet-coated metal plate, There is a problem that unevenness on the surface of the metal plate is reflected to the outermost surface of the sheet. In addition, when unevenness corresponding to the embossed design is formed on the back surface of the laminated sheet (referred to as a back texture or the like, which becomes prominent when a relatively deep embossed design is applied to the thickness of the sheet). This is due to the heat that is transferred from the metal plate during laminating, and the air that remains between the metal plate and the design laminate sheet after lamination without being excluded from the back wrinkle portion is collapsed during heating lamination. Another problem is that the smoothness of the outermost surface of the sheet deteriorates due to expansion and blistering.

  Therefore, a designable laminated sheet having a high surface smoothness in a state where a laminated sheet having an internal embossed structure is coated in a realistic thickness range as a designable laminated sheet for coating a metal plate to form a designable laminated sheet-coated metal sheet A coated metal plate is proposed in Patent Document 4. In addition, the manufacturing method of Patent Document 5 has been proposed for the same purpose.

Japanese Patent Laid-Open No. 01-14050 Japanese Patent No. 3384508 JP 2006-057248 A Japanese Patent Application Laid-Open No. 07-205368 Japanese Patent Laid-Open No. 07-132575

Patent Document 4 discloses a general internal structure in which a transparent or translucent smooth surface layer sheet and a resin sheet having an uneven design by embossing on the side laminated with the surface layer sheet are laminated and bonded via an ultraviolet curable adhesive. When laminating an embossed laminated sheet to a metal plate, a third resin sheet is interposed between the laminated sheet and the metal plate to eliminate the above-mentioned problems when laminating to the metal plate. It is what.
However, in producing this configuration, the third resin sheet is preliminarily laminated on the surface of the metal plate, and the metal plate is heated again when the laminated sheet of the internal embossed design is heat-sealed and laminated. In addition, two heating steps for the metal plate are required, and the productivity is not necessarily good. In addition, the effect of unevenness on the surface of the metal plate is reduced compared to the case where the laminated sheet of the internal embossed design is directly laminated on the metal plate, but the unevenness caused by the back wrinkles of the laminated sheet is not reflected on the surface. The effect is considered to be limited. In addition, the difference in height between the valleys and peaks of the uneven design due to embossing is small relative to the thickness of the laminated sheet, that is, it must be a shallow embossed design, and the depth feeling obtained from the internal embossed design It can be said that there is a limit to the three-dimensional effect.

The method of Patent Document 5 has an internal embossed design by laminating a soft PVC sheet having an uneven design by embossing on a metal plate in advance and then laminating a surface layer sheet via an ultraviolet curable adhesive. This is an attempt to eliminate the problems in laminating a laminated sheet to a metal plate.
However, it is impossible to eliminate the surface roughness due to the curing shrinkage of the ultraviolet curable adhesive itself. In addition, when it is desired to obtain good surface smoothness within a common thickness range as a design laminate sheet for metal plate coating, embossing with a small difference in height between the peak and valley of the embossed design It is limited to the design, and there is a problem in obtaining a design-laminated laminated sheet-coated metal plate having an internal emboss structure with a sufficient depth.

  As described above, in the design laminated sheet-coated metal plate coated with the laminated sheet having the internal embossed design, the surface has an extremely high surface in addition to being able to clearly see the relatively embossed design having a relatively three-dimensional interior. Having good smoothness is an important factor for developing high design properties. However, apart from the batch-type production method with low productivity, only the surface smoothness in the state of the design laminated sheet-coated metal plate can be obtained with any conventional configuration and production method. In spite of many patent applications, there is no actual product that is distributed as a commercial product.

  Therefore, the present invention can visually recognize the embossed design inside through a transparent surface layer having good smoothness, has an embossed design having an embossed design with a sense of depth and three-dimensionality, and a design laminate. It is an object of the present invention to provide a design-laminated laminated sheet-coated metal plate having folding workability as a sheet-coated metal plate. Another object of the present invention is to provide a method for producing the designable laminated sheet-coated metal plate and a unit bath member provided with the designable laminated sheet-coated metal plate.

The present invention will be described below.
1st this invention is a designable lamination sheet coating | cover metal plate provided with the metal plate and the lamination sheet which coat | covers this metal plate, Comprising: This lamination sheet is provided in the metal plate side most, and contains a thermoplastic resin. A composition comprising a sheet (A layer) having an uneven design by embossing on the surface and a composition containing an ultraviolet curable adhesive, and formed on the A layer with a thickness to fill the uneven design of the A layer Layer (B-1 layer), transparent biaxially stretched polyester sheet layer (C-1 layer), layer (B-2 layer) comprising a composition containing an ultraviolet curable adhesive, and transparent biaxially stretched Polyester sheet layer (C-2 layer) is provided in the order listed, and the specular gloss (Gd value) measured on the surface of the C-2 layer is 0.8 or more, and is a design-laminated sheet-coated metal plate is there.

  In the present invention, the term “sheet” is a concept that includes what is generally called “film” in addition to what is generally called “sheet” in view of its thickness. Further, “transparent” means that when another layer is laminated on the layer, visible light can be transmitted to the extent that the other layer is visible from the side opposite to the side on which the other layer is provided, and When a layer made of a composition containing an ultraviolet curable adhesive is laminated on the layer, it means that ultraviolet rays can be transmitted to the extent that the ultraviolet curable adhesive can be cured. Furthermore, the “thickness that fills the concavo-convex design of the A layer” means that the maximum height (Ry value) is the difference in height between the valley portion and the ridge portion of the concavo-convex design by embossing given to the surface of the A layer. ) Means that the thickness exceeds at least X (μm). Furthermore, “the surface of the C-2 layer” means the surface of the C-2 layer opposite to the side on which the metal plate or the like is provided in the designable laminated sheet-coated metal plate.

In the design laminated sheet-covered metal plate having the internal embossing design, first, a sheet (A layer) having an uneven design by embossing on the surface made of a composition containing a thermoplastic resin is laminated on the metal plate. Thereby, it can prevent that the unevenness | corrugation which exists in the above-mentioned metal plate surface is reflected in the surface of the C-2 layer which is the outermost surface of the designable lamination sheet coating metal plate which is a final product. At the same time, the effect of crushing when the back wrinkles present on the back surface (surface on the metal plate side) of the thermoplastic resin sheet (A layer) having an embossed design is laminated on the metal plate is finally the design property. It is also possible to prevent reflection on the surface of the C-2 layer, which forms the outermost surface of the laminated sheet-coated metal plate.
When the biaxially stretched polyester sheet (C-1 layer) is coated with a layer (B-1 layer) made of a composition containing an ultraviolet curable adhesive after laminating the A layer on the metal plate, as described above. Due to the curing shrinkage of the ultraviolet curable adhesive, irregularities corresponding to the embossed design of the surface of the A layer appear on the surface of the C-1 layer, and the smoothness of the surface of the C-1 layer becomes insufficient. However, the degree of unevenness on the surface of the C-1 layer is much gentler than the unevenness on the surface of the A layer. Therefore, by further covering the surface of the C-1 layer with a biaxially stretched polyester sheet (C-2 layer) via a layer (B-2 layer) made of a composition containing an ultraviolet curable adhesive, The surface of the C-2 layer can be a surface having extremely good smoothness. Therefore, it is possible to easily obtain a design laminated sheet-coated metal plate having a specular glossiness (Gd value) of 0.8 or more, which is one standard of surface smoothness of what is called a mirror surface product.

  In the first aspect of the present invention, the thickness of the C-1 layer is 25 μm or more and 75 μm or less, the thickness of the C-2 layer is 50 μm or more and 100 μm or less, and is applied to the surface of the A layer. When the height difference between the valleys and the peaks of the uneven design by embossing is determined as the maximum height (Ry value) according to JIS B 0601 (1994), it is preferably 45 μm or more and 150 μm or less.

  Thus, the internal embossed design can be visually recognized through a transparent surface layer having good smoothness, has an embossed design with a sense of depth and a three-dimensional effect, and is a laminated metal sheet with a designable laminated sheet. It can be set as the designable lamination sheet coating | cover metal plate provided with the bending workability as a board and the scratch resistance of the surface. Moreover, the designable laminated sheet-coated metal plate can be suitably used for designable building materials.

  The second aspect of the present invention comprises a step of laminating a sheet (A layer) having a concavo-convex design by embossing on one surface of a metal plate, comprising a composition containing a thermoplastic resin, and on the A layer. A step of applying a composition containing an ultraviolet curable adhesive to form an adhesive layer (B-1 layer) having a thickness that fills the uneven design of the A layer, and two transparent layers on the B-1 layer. A step of laminating an axially stretched polyester sheet layer (C-1 layer), a step of curing the B-1 layer by irradiating ultraviolet rays from the C-1 layer side, and an ultraviolet curable adhesive on the C-1 layer A step of applying a composition containing an agent to form an adhesive layer (B-2 layer), and a step of laminating a transparent biaxially stretched polyester sheet layer (C-2 layer) on the B-2 layer And curing the B-2 layer by irradiating ultraviolet rays from the C-2 layer side. Specular gloss measured Te (Gd value) is a manufacturing method of the design of the laminated sheet-covered metal plate is 0.8 or more.

  By adopting this manufacturing method, it is difficult to obtain with a conventional method of manufacturing a laminated sheet with a designable laminated sheet having an internal embossing design, and it has a deep feeling and a three-dimensional feeling, and at the same time has a good outermost surface smoothness. It is possible to easily obtain the designable laminated sheet-covered metal plate. In addition, this manufacturing method does not involve an excessive increase in process and energy cost.

  3rd this invention is a unit bath member provided with the designable lamination sheet coating metal plate of said 1st this invention. Unit bath members include unit bath wall materials and unit bath ceiling materials.

According to the first aspect of the present invention, the embossed design can be visually recognized through the transparent surface layer having good smoothness, and has an embossed design having an embossed design with a sense of depth and three-dimensionality, and It is possible to provide a designable laminated sheet-covered metal plate having folding workability as a designable laminated sheet-coated metal plate.
According to the second aspect of the present invention, it is difficult to obtain by a conventional method for producing a laminated metal sheet with a designable laminated sheet having an internal embossing design without excessive increase in process and energy cost. It is possible to easily obtain a designable laminated sheet-coated metal sheet having a good feeling and a three-dimensional feeling and at the same time having a good smoothness on the outermost surface.
According to 3rd this invention, the unit bath member provided with the designable lamination sheet coating metal plate of 1st this invention can be provided.

It is a schematic diagram which shows the layer structure in one Embodiment of the designable lamination sheet coating metal plate of this invention. It is a schematic diagram which shows the bonding apparatus of a roll laminating system. It is a schematic diagram which shows the measurement principle of a sharpness gloss meter. It is a schematic diagram which shows a screw bending test apparatus. It is a schematic diagram for demonstrating 180 degree | times bending (2T bending) using a screw bending test apparatus.

  The above-described operation and gain of the present invention will be clarified from embodiments for carrying out the invention described below. Hereinafter, the present invention will be described based on embodiments shown in the drawings. However, the present invention is not limited to these embodiments.

  Drawing 1 is a mimetic diagram showing layer composition in one embodiment of a designable lamination sheet covering metal plate of the present invention. As shown in FIG. 1 (a), a designable laminated sheet-coated metal plate 100, which is an embodiment of the designable laminated sheet-coated metal plate of the present invention, includes a metal plate 150 and an adhesive layer 140. A laminated sheet covering the plate 150, the laminated sheet comprising a thermoplastic resin sheet (A layer) 110 having an uneven design by embossing on the surface, and a layer (B -1 layer) 121, a transparent biaxially stretched polyester sheet layer (C-1 layer) 131, a layer (B-2 layer) 122 made of a composition containing an ultraviolet curable adhesive, and a transparent biaxially stretched polyester sheet A layer (C-2 layer) 132 is provided. In addition, in the designable laminated sheet-coated metal plate of the present invention, each of the above layers does not need to be a single layer, and may be composed of two or more layers. For example, as will be described later, the A layer may be composed of two layers 111 and 112 (see FIG. 1B). Hereinafter, these layers will be described in detail.

(Thermoplastic resin sheet (A layer) having an uneven design on the surface)
A layer 110 shown in FIG. 1 is laminated with a transparent biaxially stretched polyester film layer (C-1 layer) 131 via a layer (B-1 layer) 121 made of a composition containing an ultraviolet curable adhesive. It is a layer which has the uneven | corrugated design by embossing on the surface of the side to be done. In the present invention, prior to laminating the B-1 layer and the C-1 layer, only the A layer 110 is laminated on the metal plate 150 with embossing.
A laminated sheet having an internal embossed design, or a designable laminated sheet-coated metal plate itself coated with the laminated sheet is known in the art, and the resin composition of the thermoplastic resin sheet to be the A layer 110 is also conventionally known. You can use what has been used.
In general, the performance required for a thermoplastic resin sheet with an embossed design on the surface provided for a laminated sheet with an internal embossed design for use in a designable laminated sheet coated metal sheet is easy to form a sheet. In addition, it satisfies the manufacturing requirements such as easy embossing of the surface by embossing on the surface, and no remarkable embossing return due to heat received from the metal plate during heat lamination to the metal plate. . In addition, when a laminated sheet with a designable laminated sheet coated with a laminated sheet having an internal embossed design, which is the final configuration, is provided with physical properties that satisfy product requirements such as bending workability specified for each application. Is also necessary.

As a material satisfying these performances, a so-called soft vinyl chloride resin, which has been improved in flexibility from about 0 ° C. to about room temperature by adding a plasticizer, has been used for many years. The soft vinyl chloride resin can also be suitably used as the plastic resin sheet.
The soft vinyl chloride resin can be easily formed into a sheet by a calendering method that excels in color changeability in a small lot. Moreover, since it has the suitability for the embossing apparatus provided off-line, it has a small lot correspondence also about an embossing design. On the other hand, embossing heat resistance against heating when laminating to metal plate (resistance to embossing becoming unclear when heated (embossing return occurs). Embossing return occurs even when heat is applied if the embossing heat resistance is high. It is difficult, and when the heat resistance of the emboss is low, the emboss return easily occurs when heat is applied.) Although there is some dissatisfaction, in the present invention, the A layer 110 is first laminated on the metal plate 150. Therefore, the C-2 layer 132, which is the outermost layer, and other transparent resin layers are coated, so that the lack of emboss heat resistance during lamination does not deteriorate the smoothness of the outermost layer. Moreover, the point which can obtain the designable lamination sheet coating metal plate 100 which has favorable workability is also the characteristics.

  On the other hand, some users tend to dislike the VOC component contained in soft vinyl chloride resin, and it is considered as the main application of the design laminated sheet coated metal sheet with internal embossing structure. In particular, the tendency is strong. In order to meet the demand, a thermoplastic resin sheet replacing various kinds of soft PVC, and a design laminated sheet-covered metal plate covering the thermoplastic resin sheet have been proposed. Examples thereof include polyolefin resin-based sheets, polyester resin-based sheets, acrylic resin-based sheets, and the like, and these can also be preferably used for the A layer 110 of the present invention.

  For polyolefin resin-based sheets, polypropylene resin or polyethylene-based resin is the main resin component, and various soft components that can be dispersed relatively finely are blended therein, so that the metal coated with the polyolefin resin-based sheet It is known that the plate can ensure the bending workability as a resin-coated metal plate. In addition, by blending various additives for improving the calendering property, a calendering device that has been used for forming a conventional soft vinyl chloride resin sheet can be used as it is. Regarding embossing, there is an advantage that a conventional embossing apparatus can be used as it is. In many cases, the scratch resistance of the sheet surface is inferior to that of the soft vinyl chloride resin sheet. However, in the present invention, since the A layer 110 does not become the outermost surface of the designable laminated sheet-coated metal plate 100, it can be used without any trouble. Further, the embossing heat resistance is at a level not much different from that of a soft PVC resin, but this is not a problem in the present invention.

Polyester resins contained in the polyester resin sheet include polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene isophthalate (PEI), polyethylene naphthalate (PEN), and polyethylene terephthalate mainly composed of ethylene terephthalate units. Ethylene isophthalate copolymer (PETI), polybutylene terephthalate isophthalate copolymer (PBTI), polytrimethylene terephthalate (PTT), cyclohexanedimethanol copolymerized polyethylene terephthalate (PETG and PCTG), spiroglycol copolymerized polyethylene terephthalate , Neopentyl glycol copolymer polyethylene terephthalate, polybutylene naphthalate (PBN), dicarboxylic acid An aromatic polyester system in which the main component is terephthalic acid or a derivative thereof, and the diol component is 1,4-cyclohexanedimethanol and 2,2,4,4, -tetramethyl-1,3-cyclobutanediol Examples thereof include resins and blends obtained by mixing two or more of these resins.
Among these, an amorphous polyester resin is easy to obtain a sheet with a calendering apparatus by blending a required additive, and is excellent in small lot suitability. Moreover, the transfer property of embossing is also good, and good transfer can be imparted by a conventional embossing apparatus. On the other hand, when the glass transition temperature is less than 100 ° C., the embossing heat resistance is low. In addition, when subjected to a boiling water immersion test included as an evaluation item of a designable laminated sheet-coated metal plate for unit bath use, significant fluid deformation occurs in the A layer 110, and the designable laminated sheet-coated metal plate of the present invention. This is not preferable when 100 is used for a unit bus. However, even with non-crystalline polyester resins, the above problems can be avoided if the glass transition temperature exceeds 100 ° C., which also hinders the design laminated sheet coated metal plate used for unit bath applications. Can be used without any problems.

On the other hand, in the case of a crystalline polyester-based resin, it is possible to ensure good embossing heat resistance by crystallization after embossing. However, in the case of a highly crystalline PET-based resin, when it is crystallized without orientation, it will be in a state where cracks will occur even when the resin sheet is bent alone, so that the laminated sheet coated with a designable laminated sheet It is difficult to apply to the intended use. In addition, since the crystallization speed is relatively slow, the crystallization treatment for securing the emboss heat resistance brings about a reduction in productivity.
In contrast, PBT-based resins and PTT-based resins have a high crystallization speed and can be rapidly subjected to crystallization treatment to ensure embossing heat resistance. Since it is higher than the heating temperature of the processing apparatus, embossing is limited to a so-called extrusion cast embossing method in which emboss engraving is performed on a take-up roll of a thermoplastic extruder.
However, by appropriately blending and laminating crystalline resin and amorphous resin, the crystallization speed can be adjusted, and non-adhesiveness to heated metal rolls can be secured. It is also possible to give the aptitude of In addition, regarding the required performance for each application of the designable laminated sheet-coated metal plate, it is possible to obtain a resin composition / configuration satisfying the requirements by blending or lamination. The A layer 110 made of these polyester resins is preferably used in an unstretched state in order to obtain good emboss transferability.
In addition, the expression of non-stretching here is that the orientation treatment such as stretching operation was not performed intentionally to give some performance to the sheet, and the film was drawn (drawed) by a casting roll during extrusion film formation. It does not mean that there is no orientation or the like that occurs in

As an acrylic resin-based sheet, a so-called core-shell type rubber component having a graft chain for improving compatibility with the matrix resin is added from the vicinity of 0 ° C. with the cross-linked elastic component as a core. An acrylic resin having good flexibility near room temperature can be used.
The acrylic resin can be formed into a sheet by a calender method which is excellent in small lot compatibility. Moreover, the emboss transfer by the conventional embossing apparatus is also possible. The scratch resistance on the surface is inferior to that of the soft vinyl chloride resin sheet, but it is not a problem in the configuration of the present invention. However, it is known that when a large amount of a cross-linked elastic component is added for the purpose of improving workability, the transferability of embossing is deteriorated due to the rubber elasticity, and the design of internal embossing is sufficient. Therefore, if the transferability of the emboss is maintained, the processability as a resin-coated metal plate may be restricted.

The resin composition of the A layer 110 is not necessarily limited to these. It is a thermoplastic resin, can be made into a sheet and embossed, and can be laminated on the metal plate 150, and satisfies the evaluation items specified for each use of the design-use laminated sheet-coated metal plate 100. If it is a thing, and a raw material price and manufacturing cost are what can be used for a designable laminated sheet covering metal plate, it can be used as the A layer 110.
Examples of other resin sheets include aromatic polycarbonate resin-based sheets, non-aromatic polycarbonate resin-based sheets, aliphatic / alicyclic polyester resin-based sheets, MBS resin-based sheets, ABS resin-based sheets, and thermoplastic urethanes. Examples include resin-based sheets. Ensuring raw material price, avoiding VOC problems, and embossing heat resistance during actual use in unit bath applications (if the embossing returns due to hot water being applied during use, surface smoothness will also deteriorate). In view of the above, the A layer 110 made of a polyester resin containing a crystalline resin component or a polyester resin mainly composed of a polyester resin having a high glass transition temperature is considered to be particularly preferable.

The A layer 110 is required to visually conceal the metal plate 150 to be coated, and the layer that imparts a design of color to the design laminated sheet-coated metal plate 100 is the A layer 110. A pigment component is added. The pigment may be one generally used for the above-mentioned purpose, and can be selected according to the use of the finally-designed laminated sheet-coated metal sheet 100. In the case of coloring white, a titanium oxide pigment having a fine particle diameter that has a high concealing effect and little influence on the processability of the laminated sheet is preferable. In the case of white chromatic coloring, a small amount of chromatic organic and inorganic pigments can be added in order to adjust the color tone with the titanium oxide pigment as a main component.
If the blending amount of the pigment in the resin constituting the A layer 110 is too large, the sheet strength becomes insufficient. Therefore, the total amount of the resin components of the A layer 110 should be 50% by mass or less based on the standard (100% by mass). Is preferred. More preferred is 40% by mass or less, and particularly preferred is 30% by mass or less.

  On the other hand, in the laminated sheet having the internal embossed structure, in order to improve the visibility of the internal embossing, a glitter pigment is added to the layer to which the uneven design by embossing is added, or an embossed design is applied. It is known that it is necessary to form a printing layer containing a glitter pigment on the surface. This is because, in a laminated sheet with an embossed design on the normal outer surface, unevenness due to embossing is present at the interface with air, so the refraction of air and resin, regardless of the presence or absence of a bright pigment. The embossed design is clearly visually recognized due to the difference in the ratio, whereas in the laminated sheet having the internal embossed structure, the unevenness due to the embossing is different from the refractive index of the resin composition of the embossed sheet (A layer 110 of the present invention). This is because it is located between the adhesive layer (B-1 layer 121 of the present invention) having a refractive index that is not significantly different. Thus, when the A layer 110 is a transparent resin layer to which no pigment is added, the unevenness due to the internal embossing is not visually recognized at all. In addition, when only the titanium oxide pigment having a strong scattering reflection property is added to the A layer 110, the visibility of the internal embossing is significantly lowered due to the strong scattering reflection of the light incident on the A layer 110. Furthermore, even when only a black pigment such as carbon black, which has a strong light absorption, is added, the visibility at the embossed interface is greatly reduced and the visibility of the internal embossing is reduced. It becomes impossible to obtain good visibility of embossing. Therefore, in order to improve the visibility of the internal embossing, it has a refractive index different from that of the adhesive composition applied on the concavo-convex design by embossing, and has a reflection characteristic having a certain degree of regularity. It is necessary to add or coat a material having the above, and it can be said that a material suitable for imparting such characteristics is a glitter pigment.

The bright pigments added for the above reasons include pearl mica pigments with titanium oxide coating on the surface of natural mica and synthetic mica, and silver, nickel, other various metals and metal oxides such as titanium oxide on the surface. Shredded thin film glass that has been coated, metal flakes such as aluminum flakes, finely cut metal foils such as aluminum foil, and finely cut metal foils such as aluminum foil surface-treated with epoxy resin And pigments obtained by finely cutting resin sheets obtained by electroless plating of various metals. Hereinafter, a typical pearl mica pigment will be described as a bright pigment used for obtaining good visibility of internal embossing. The pearl mica pigment is a pigment having a structure in which a titanium oxide layer having a high refractive index (nD) is coated on a surface layer of a mica pigment having a low refractive index, and has a so-called scale-like shape having a sufficiently large diameter with respect to the thickness. Alternatively, it is a particle having a shape that is described as a flat plate or the like.
Due to the characteristics of the particle shape, when a glitter pigment is added to the resin sheet with the embossed uneven design on the surface, or when a printing layer containing the glitter pigment is applied to the surface of the embossed uneven design. The multilayer structure having the refractive index difference parallel to the surface of the sheet enables multiple regular reflections of light from the surface of the A layer 110 made of the sheet. It is presumed that the uneven design by embossing is visually enhanced by the reflectivity and the visibility of the uneven design is improved.
Various commercially available pigments can be used as the luster pigment, and pearl mica pigments having various particle sizes are available from BASF, Merck and the like. Commercially available pearl mica pigments colored in chromatic colors and pearl mica pigments exhibiting interference colors are also available. In addition, Ultima (manufactured by Nippon Koken Co., Ltd.), Crystal Star (manufactured by Toyo Aluminum Co., Ltd.), Meta Shine (manufactured by Nippon Sheet Glass Co., Ltd.), etc. can be used. In the present invention, a pearl mica pigment that expresses a special design feeling using the specific optical properties of the glitter pigment (for example, an interference color for giving a design feeling that changes in color depending on the viewing angle) It is particularly preferable to use the most general-purpose pearl mica pigments, except when trying to obtain the above.

The bright pigment may be added to the A layer 110 as a single-layer sheet, mixed with a pigment component added for imparting a design of color or concealing the base, but more visually embossed. For the purpose of improving the properties, the layer 112 having the A layer 110 as a two-layer structure as shown in FIG. 1 (b), the metal plate 150 side added with a pigment component for imparting tint or concealing the base, It is particularly preferable that the side to which the embossed design is applied is the semi-translucent layer 111 to which a bright pigment is added.
In addition, embossing may be applied after the embossed design is applied on the surface to which the embossed design is applied, followed by embossing. In this case, the embossed design is applied as the resin composition (vehicle component) of the printed layer. When the sheet of the A layer 110 is sometimes heated and pressed by the embossing roll, it is necessary to appropriately select one that does not peel off or drop off or cause significant adhesion to the embossing roll.

  In order to improve the visibility of the internal embossed design, it is only necessary to obtain regular reflection in the vicinity of the interface where the embossed design exists as described above. It is also conceivable to form a metal reflective layer on the surface of the embossed design by metal deposition, lamination of aluminum foil, or the like. Alternatively, the difference in refractive index (nD) measured according to JIS K 0062, which is generally known as a method for producing a resin composition having a pearly luster, is incompatible with 0.01 to 0.1. A blend composition comprising a plurality of resins that are capable of forming a fine dispersion structure to some extent (an example of a combination of resins is an acrylic resin (nD = 1.49) and an aromatic polycarbonate resin (nD = 1.586) etc.)), and a method of using as a resin layer at least the surface of the A layer 110 to which the embossed design is applied is considered. Alternatively, it is known as a method for obtaining a resin sheet having no metallic reflection and having a metallic reflection, and super multi-layers of resins having a refractive index (nD) difference between 0.01 and 0.1 are laminated. By appropriately adjusting the number of layers and the thickness of each layer, a sheet having appropriate translucency and metallic reflection is obtained, and this is used as a resin layer that forms at least the surface of the A layer 110 to which the embossed design is applied. A method is also conceivable.

  In the thermoplastic resin composition constituting the A layer 110, various additive components can be blended in appropriate amounts in addition to the pigment component as long as the object of the present invention is not impaired. Examples of resin additives include antioxidants such as phosphorus compounds and phenol compounds, process stabilizers such as phenol acrylate compounds, heat stabilizers, ultraviolet absorbers, hindered amine radical scavengers, various processing aids, metal additives. Examples include activators, lubricants, antibacterial / antifungal agents, antistatic agents, flame retardants, pigment dispersibility improvers, and fillers / extenders. Furthermore, when the base resin of the A layer 110 is a polyester resin, a terminal carboxylic acid sealing agent such as a carbodiimide, epoxy, or oxazoline, or a hydrolysis inhibitor may be blended.

  Although there is no restriction | limiting in particular regarding the thickness of A layer 110, It is preferable that they are 100 micrometers or more and 300 micrometers or less. If the A layer 110 is excessively thick, the thickness of the resulting laminated sheet will also be like a plate-like body, which will also hinder the winding of long products, and a laminated sheet coated with a designable laminated sheet obtained by laminating this However, it is difficult to obtain secondary workability such as bending workability. When the thickness is less than 100 μm, it is only possible to obtain a shallow emboss with a small difference in height between the valley and the peak of the embossed design that can be applied to the A layer 110, and the internal embossing rich in three-dimensionality and depth The design cannot be obtained. In addition, when using the A layer 110 having only such a shallow embossed design, it is needless to use the method of the present invention. The thickness of the A layer 110 is more preferably 120 μm or more and 260 μm or less, and particularly preferably 150 μm or more and 250 μm or less.

The preferred range of the height difference between the valley and the peak of the embossed design applied to the surface of the A layer 110 in the present invention is 45 μm or more and 150 μm or less at the maximum height (Ry value). The thickness of the sheet of the layer 110 is preferably 1.2 times or more and about 6 times or less of the plate depth (maximum depth / Ry value) of the embossing roll from the viewpoint of good transfer of the embossed design. It is more preferably 1.4 times or more and 3 times or less. If the thickness is smaller than this, the surface opposite to the surface of the sheet pressed with the embossing roll is called “back texture” although it depends on the type of plate (in this case, the side laminated with the metal plate 150 of the A layer 110) There is a possibility that unevenness due to the reflection of the embossed pattern on the surface) may occur remarkably. In the present invention, the outermost surface on the design surface side of the designable laminated sheet-coated metal sheet 100 finally obtained even when the resin sheet of the A layer 110 in which the “back wrinkles” are remarkable is used. The sheet having a remarkable “back wrinkle” does not affect the smoothness of the surface of the C-2 layer 132, but the back wrinkle is crushed when laminating to the heated metal plate 150. The design feeling of the embossed design itself applied to the surface of the layer 110 is lowered, or it is laminated with air bubbles in the back embossed part, resulting in a blister-like blistering. There is a risk of worsening.
Even when the ratio of the sheet thickness to the plate depth of the embossing roll exceeds three times, no further improvement in transfer can be obtained.

  As for the embossing design imparting method to the A layer 110, various design methods conventionally used for embossing a designable sheet made of a thermoplastic resin or embossing on a designable sheet-coated metal plate are used without limitation. However, as described above, an optimal embossing design imparting method is selected depending on the resin composition and configuration constituting the A layer 110. Examples of embossing design application methods include: (1) A method of applying the embossing design at the same time that the resin composition of the A layer 110 immediately after being melted down from the T-die is drawn by a casting roll engraved with an embossed pattern; 2) A film forming facility includes an embossing apparatus provided off-line, and a method of applying an embossed design by passing the formed sheet through reheating and the like.

  In the present invention, when the difference in height between the valley portion and the mountain portion of the embossed design applied to the surface of the A layer 110 is determined as the maximum height (Ry value) in accordance with JIS B 0601 (1994), 45 μm As mentioned above, it is preferable that it is 150 micrometers or less. The maximum height (Ry value) is, of course, the maximum value of the height of unevenness as an embossed design, and foreign matter and bubbles are interposed between the resin sheet of the A layer 110 and the metal plate 150. Defects in which the height of the ridges of the embossed design specifically increases due to, etc., or the depths of the ridges or valleys where only a part of the ridges are increased due to defects or damage in the embossed plate It should be measured by eliminating defective parts such as the part where the increase is.

In general, if the height difference between the valley and the peak of the embossed design is 45 μm or more at the maximum height (Ry value), sufficient solidity and depth can be achieved in the laminated sheet with the internal embossing structure. I can feel it. In addition, when the height of the unevenness of the embossed design is less than 45 μm, it is relatively easy to obtain a good surface smoothness only by laminating one layer of the biaxially stretched polyester sheet without using the method of the present invention. It is. Moreover, if the maximum height of the unevenness | corrugation by an embossing design is 150 micrometers or less, in order to make the outermost surface (surface of the C-2 layer 132) of the designable lamination sheet coating | coated metal plate 100 favorable favorable by the method of this invention. In addition, it is not necessary to select a relatively thick biaxially stretched polyester sheet used as the C-1 layer 131 and the C-2 layer 132, or the coating thickness of the adhesive composition (B-1 layer). 121, the thickness of the B-2 layer 122) does not need to be relatively thick, and there is no problem in secondary workability such as a bending process as a designable laminated sheet-coated metal plate.
Of course, the larger the maximum embossing height (Ry value), the more embossed design can be obtained with a sense of depth and depth. To obtain a large Ry value, first, the A layer 110 In addition, in order to ensure surface smoothness, the thickness of the B-1 layer 121 and / or the thickness of the C-1 layer 131 needs to be relatively thick. The B-2 layer 122 and / or the C-2 layer 132 may have to be relatively thick. Therefore, the embossed design having a large Ry value increases the thickness of the entire laminated sheet, and in addition to the workability of the designable laminated sheet-coated metal sheet, the Ry value is 120 μm or less from the viewpoint of cost. It is preferable that the thickness is 100 μm or less.

(Lamination of layer A to metal plate)
The method for laminating the sheet of the A layer 110 obtained as described above to the metal plate 150 is not particularly limited, but laminating with a thermosetting adhesive is common. As the adhesive, thermosetting adhesives that have been used for the purpose of laminating soft PVC sheets to metal plates, such as acrylic adhesives, epoxy adhesives, urethane adhesives, polyester adhesives, etc. Can be used.
As an example of a specific method for laminating to a metal plate, first, using a commonly used coating equipment such as a reverse coater, a kiss coater, etc., on the surface of the metal plate 150 on the side where the A layer 110 is bonded, The thermosetting adhesive is applied so that the adhesive film thickness after drying is about 1 μm to 10 μm. Next, the coated surface is dried and heated by an infrared heater and / or a hot air heating furnace, and the surface temperature of the metal plate 150 is maintained at a temperature of about 210 ° C. to 250 ° C., and immediately using the roll laminator, the A layer 110 Then, the embossed design applied to the surface of the A layer 110 is cooled by an appropriate cooling method such as water cooling before the embossed return occurs, whereby the metal plate 150 coated with the A layer 110 can be obtained.

  As the metal plate 150 to be the subject of the present invention, those conventionally used for design-oriented laminated sheet-coated metal plates can be used without particular limitation, for example, cold-rolled steel sheet, hot-dip galvanized steel sheet, Various types of steel such as electrogalvanized steel sheet, zinc / aluminum alloy plated steel sheet, zinc / aluminum / magnesium alloy plated steel sheet, tin plated steel sheet, tin-free steel, stainless steel sheet, aluminum alloy plate, nickel alloy plate, titanium alloy plate, A magnesium alloy plate or the like can be used.

  The thickness of the metal plate 150 varies depending on the use of the design laminated sheet-coated metal plate 100, but can be selected in the range of about 0.1 mm to 3 mm. As an example, the thickness of the unit bath is 0.3 mm to 0 mm. A thickness of about 8 mm is often used.

(Consisting of an adhesive composition containing an ultraviolet curable adhesive (B-1 layer and B-2 layer))
The B-1 layer 121 and the B-2 layer 122 are made of an adhesive composition containing an ultraviolet curable adhesive. The adhesive composition is mainly composed of an ultraviolet curable adhesive, and the ultraviolet curable adhesive is preferably composed mainly of an acrylate resin. The acrylate resin in the present invention refers to an acrylate resin containing an acrylate oligomer and / or a component derived from an acrylate monomer. In addition, "main body" means here what contains in the range of 50 mass% or more on the basis of the mass of the whole composition (100 mass%). If the ultraviolet curable adhesive contained in the adhesive composition is 50% by mass or more, the initial curability of the adhesive composition is sufficiently exhibited. Phenomenon that the adhesive composition protrudes, peeling at the interface with the transparent biaxially stretched polyester sheet layer (C-1 layer 131 and C-2 layer 132) does not occur, and cutting or bending until the curing is completed There is no problem that the secondary processing cannot be performed. In addition, the content ratio of the component derived from an acrylate oligomer and / or an acrylate monomer is not particularly limited, and from the viewpoint of adhesive properties and workability of the composition, the acrylate oligomer is 30 parts by mass to 70 parts by mass. On the other hand, the range of 70 mass parts-30 mass parts of components derived from an acrylate monomer is preferable.

The acrylate oligomer is a compound having one to several acryloyl groups (CH ₂ ═CHCO—) or methacryloyl groups (CH ₂ ═CCH ₃ CO—) in the molecule and having a molecular weight of hundreds to thousands. Say. Representative examples include mono (meth) acrylates such as epoxy, epoxidized oil, urethane, polyester, and polyether, di (meth) acrylate, tri (meth) acrylate, and polyfunctional (meth) acrylate. Such acrylate-based oligomers are commercially available, and commercially available products include Aronix (manufactured by Toagosei Co., Ltd.), Art Resin (manufactured by Negami Kogyo Co., Ltd.), NK Oligo (manufactured by Shin-Nakamura Chemical Co., Ltd.), New Frontier (Daiichi Kogyo). (Manufactured by Pharmaceutical Co., Ltd.).

  Examples of the acrylate monomer include monofunctional and bifunctional or higher polyfunctional monomers. Monofunctional (meth) acrylate monomers include acryloylmorpholine, dimethylacrylamide, diethylacrylamide, diisopropylacrylamide, isobornyl acrylate, 2-hydroxy (meth) acrylate, 2-hexyl (meth) acrylate, and phenoxyethyl (meth) acrylate. Etc. Examples of the bifunctional (meth) acrylate include ethylene glycol di (meth) acrylate and 1,6-hexanediol di (meth) acrylate. Furthermore, examples of the trifunctional or higher functional (meth) acrylate include trimethylolpropane tri (meth) acrylate, pentaerythritol tri (tetra) (meth) acrylate, and dipentaerythritol hexa (meth) acrylate.

  When the monomer is selected, if flexibility is required for the B-1 layer 121 and the B-2 layer 122, the amount of the monomer is reduced within a range that does not hinder the coating operation, and the monofunctional or bifunctional (meta) ) Use an acrylate monomer and make the structure less crosslinked. When the B-1 layer 121 and the B-2 layer 122 are required to have heat resistance, water resistance, etc., the amount of the monomer is increased within a range that does not hinder the coating operation, and the trifunctional or higher (meta- ) By using an acrylate monomer, a structure having a high degree of crosslinking can be obtained. In addition, a monofunctional monomer, a bifunctional monomer, and a trifunctional or higher monomer can be mixed to adjust the coating operation and the physical properties of the cured product.

  The above UV curable adhesive contains UV sensitive photopolymerization initiator and photosensitizer (or contains), and is irradiated with UV light to cause photopolymerization and cure easily. Can be made.

  Examples of the ultraviolet-sensitive photopolymerization initiator include 1-hydroxycyclohexyl phenyl ketone, 2,2-dimethoxy-2-phenylacetophenone, xanthone, fluorenone, benzaldehyde, fluorene, anthraquinone, triphenylamine, carbazole, 3-methylacetophenone. 4-chlorobenzophenone, 4,4′-dimethoxybenzophenone, 4,4′-diaminobenzophenone, Michler's ketone, benzoin propyl ether, benzoin ethyl ether, benzyldimethyl ketal, 1- (4-isopropylphenyl) -2-hydroxy-2 -Methylpropan-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, thioxanthone, diethylthioxanthone, 2-isopropylthioxanthate , 2-chlorothioxanthone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-1-one, such as 2,4,6-trimethylbenzoyl diphenylphosphine oxide.

  Various types of UV-sensitive photopolymerization initiators are commercially available. Irgacure 184, 651, 500, 907, CG1369, CG24-61 (above, manufactured by Ciba Specialty Chemicals), Lucillin LR8728 (BASF) DAROCURE 1116, 1173 (manufactured by Merck), Ubekrill P36 (UCB), and the like are available.

  Examples of photosensitizers include triethylamine, diethylamine, N-methyldiethanolamine, ethanolamine, 4-dimethylaminobenzoic acid, methyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate, and the like. Is mentioned. Various types of photosensitizers are commercially available, and Ubekryl P102, 103, 104, 105 (above, manufactured by UCB) and the like are available.

  The amount of the photopolymerization initiator used is 0.1% by mass to 10% by mass based on the mass (100% by mass) of the entire ultraviolet curable adhesive forming the B-1 layer 121 and the B-2 layer 122. % Can be blended. The amount in the case of using a photosensitizer is 0.05% by mass based on the mass (100% by mass) of the entire ultraviolet curable adhesive forming the B-1 layer 121 and the B-2 layer 122. It is the range of -5.0 mass%.

  In addition, the adhesive composition for forming the B-1 layer 121 and the B-2 layer 122 has durability of the B-1 layer 121 and the B-2 layer 122 in addition to the ultraviolet curable acrylate resin. For the purpose of adjustment, resin components other than the ultraviolet curable resin can be added. Examples of the resin component include thermoplastic resins such as urethane resins, polyester resins, acrylic resins, butyral resins, polyvinyl chloride, and polyvinyl acetate. Among these, from the viewpoint of heat and humidity resistance, a urethane-based resin prepolymer is preferable, and an isocyanate-terminated urethane prepolymer is particularly preferable. Moreover, the addition amount of resin components other than ultraviolet curable resin is 4 mass% on the basis of the mass of the whole adhesive composition which comprises the B-1 layer 121 and the B-2 layer 122 (100 mass%). It is preferable that it is more than 50 mass%, and it is more preferable that it is 6 mass% or more and less than 20 mass%. If the addition amount is 4% by mass or more, the durability of the B-1 layer 121 and the B-2 layer 122 can be sufficiently improved. On the other hand, if the addition amount is less than 50% by mass, the hygroscopic foaming property of the adhesive composition can be suppressed, and the pot life is not limited. In addition, the initial curability at the time of ultraviolet irradiation is sufficiently exhibited, the phenomenon that the adhesive composition protrudes from the end surface of the design resin sheet-coated metal plate 100, and the transparent biaxially stretched polyester sheet layer (C-1 layer 131, In addition, there is no occurrence of separation at the interface with the C-2 layer 132), and there is no problem that secondary processing such as cutting and bending cannot be performed until curing is completed and the reaction of the isocyanate group is completed. .

The adhesive composition for forming the B-1 layer 121 and the B-2 layer 122 includes a component derived from an acrylate oligomer and / or an acrylate monomer, an ultraviolet-sensitive photopolymerization initiator, and a photosensitizer. In some cases, a predetermined amount of a resin component other than the ultraviolet curable resin is weighed and uniformly mixed by a mixing and stirring device.
The adhesive composition preferably has a viscosity in the range of 1 (Pa · s) to 2000 (Pa · s). If the viscosity is 1 (Pa · s) or higher, the thickness of the embossed design with the unevenness of the embossed design is balanced, and the filling of the embossed design with the unevenness of the embossed design and the flow prevention of the filled adhesive are balanced. It becomes possible to apply. As a result, excellent smoothness of the surface of the C-2 layer 132 can be obtained in the configuration of the present invention. On the other hand, if the viscosity is 2000 (Pa · s) or less, the adhesive composition is easy to handle at room temperature, and it is excellent in workability such as not requiring heating. A particularly preferable range of the viscosity is from 1.5 (Pa · s) to 1000 (Pa · s). In the present invention, the viscosity of the adhesive composition refers to a value measured with a B-type viscometer at a temperature of 25 ° C.

The adhesive composition mainly composed of an ultraviolet curable adhesive used for the B-1 layer 121 and the B-2 layer 122 has a tensile breaking strength after curing by ultraviolet irradiation of 20 MPa to 50 MPa, and an elongation at break of 200. It is preferable that it is the range of% -600%. The designable laminated sheet-coated metal plate 100 according to the present invention is generally subjected to secondary processing such as shearing and bending, and when the thickness of the designable laminated sheet-coated metal plate 100 increases, Since the elongation at the outermost surface of the sheet when it is bent with the side coated with the sheet as the outer surface is increased, the adhesive at the time of secondary processing if the tensile breaking strength of the laminated sheet after curing is 20 MPa or more The layer (B-1 layer 121 and B-2 layer 122) and the C-2 layer 132 which is the outermost surface sheet are not cracked, cracked or peeled off. The same applies when the elongation at break is 200% or more.
In the design laminated sheet-coated metal sheet 100, the C-2 layer 132 as the outermost surface needs to be formed of a biaxially stretched polyester sheet that does not have a large tensile elongation at break, and as an intermediate layer. Since the biaxially stretched polyester resin sheet C-1 layer 131 is applied, the B-1 layer 121 and the B-2 layer 122, which are adhesive layers, are relatively flexible, 200% or more. It is preferable from the point of securing the secondary workability that it is composed of a composition having an elongation at break and is a layer that absorbs the stress when deformed as a designable laminated sheet-coated metal plate by deformation. .

  Here, the tensile strength at break and the elongation at break of the adhesive composition after curing are the B-1 layer 121 and the B-2 layer on the surface of a biaxially stretched polyester sheet or the like having a release property on the surface. After the 122 adhesive composition was applied at an appropriate thickness of about 100 μm to 200 μm, it was cured by light irradiation under the same conditions as in the production of an actual product, and this cured film was separated from the biaxially stretched polyester sheet. It peels from a mold processing surface, prepares the test piece for a measurement of tensile breaking strength and breaking elongation, and measures these test pieces based on JISK7127.

(Transparent biaxially stretched polyester sheet layer (C-1 layer and C-2 layer))
The purpose of providing the C-1 layer 131 is to form a relatively smooth surface with the C-1 layer 131 rather than the unevenness due to the embossed design on the surface of the A layer 110, as described above. The surface smoothness of the C-2 layer 132 is made extremely high by forming the B-2 layer 122 thereon and covering the C-2 layer 132. Therefore, it is preferable that the resin sheet constituting the C-1 layer 131 has physical properties that make it difficult to reflect the curing shrinkage of the B-1 layer 121 on the surface. Specifically, a resin sheet having a relatively high flexural modulus is preferable, and a sheet having high transparency is required because it is necessary to ensure the visibility of the internal embossed design. Furthermore, the adhesiveness with the ultraviolet curable adhesive is good, the handling property at the time of laminating is good, and it is necessary to be of a price that can be used for a design-use laminated sheet-coated metal plate for building materials. .
On the other hand, the resin sheet constituting the C-2 layer 132 also has good transparency, good adhesion with an ultraviolet curable adhesive, and good handling properties during lamination. The same performance as that of the C-1 layer 131 is required, such as a price that can be used for the designable laminated sheet-coated metal plate. Moreover, since C-2 layer 132 is a layer which comprises the outermost surface of the designable lamination sheet covering metal plate 100, the resin sheet itself which comprises C-2 layer 132 has favorable smoothness. In addition, it is a requirement that is generally required as a metal sheet coated with a design-oriented laminated sheet, such as having scratch resistance on the surface, resistance to alkali cleaning agents, and good resistance to various chemicals used in general households. It is necessary to satisfy.

As a resin sheet that satisfies these requirements, it is preferable to use a biaxially stretched transparent polyester sheet for both the C-1 layer 131 and the C-2 layer 132.
Polyester sheet materials include polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polytrimethylene terephthalate (PTT), polyethylene naphthalate (PEN), polybutylene naphthalate (PBN), polytrimethylene naphthalate (PTN). ) And the like, and copolymers having a structure in which a part of these dicarboxylic acid components and / or diol components are substituted with other dicarboxylic acid components and diol components, and a mixture of two or more of these resins. It is done. In addition, the resin compositions of the sheets of the C-1 layer 131 and the C-2 layer 132 may be the same or different. Among these, a biaxially stretched transparent polyethylene terephthalate resin sheet can be particularly preferably used as a sheet constituting the C-1 layer 131 and the C-2 layer 132. Biaxially stretched transparent polyethylene terephthalate resin sheets with various thicknesses are commercially available, and there are also grades that are easy to obtain and that have been subjected to easy adhesion treatment to improve adhesion with UV curable adhesives. It is prepared by each manufacturer.
The transparent biaxially stretched polyethylene terephthalate sheet can be preferably used as the C-1 layer 131 having a thickness of 25 μm or more and 75 μm or less, which has been subjected to an easy adhesion treatment on both sides. One having a thickness of 50 μm or more and 100 μm or less, which has been subjected to an easy adhesion treatment on at least one surface, can be preferably used.
If the biaxially stretched polyethylene terephthalate sheet used as the C-1 layer 131 is 25 μm or more, the degree of unevenness on the surface of the C-1 layer 131 is far greater than the unevenness due to the embossed design on the surface of the A layer 110 as described above. The purpose of providing the C-1 layer 131, which is to be gentle, can be sufficiently achieved. As a result, the smoothness of the surface of the C-2 layer 132, which is the outermost surface on the side having the designability of the designable laminated sheet-coated metal plate 100, is also sufficient. If the thickness of the C-1 layer 131 is 75 μm or less, there will be no problem in the bending workability of the designable laminated sheet-coated metal plate 100 as described above. From the viewpoint of workability, the thickness of the C-1 layer 131 is more preferably 50 μm or less.

The C-2 layer 132 is also a resin layer that forms the outermost surface on the side having the designability of the designable laminated sheet-coated metal sheet 100, although it causes a problem in bending workability when it is excessively thick. Therefore, it is easier to ensure the smoothness of the outermost surface by using a biaxially stretched polyethylene terephthalate sheet that is 50 μm or more and 100 μm or less and thicker than the C-1 layer 131. Moreover, it is preferable to select a biaxially stretched polyethylene terephthalate sheet in the above thickness range from the viewpoint of improving the scratch resistance of the surface, and from the viewpoint of smoothness and scratch resistance, it should be 75 μm or more. Is more preferable.
In addition, as the biaxially stretched polyester resin-based sheet, both the C-1 layer 131 and the C-2 layer 132 may be printed with a pattern as long as the visibility of the internal embossed design is not hindered. As for the first layer 131, the B-1 layer 121 side surface and / or the B-2 layer 122 side surface provided with a printing layer can be used, and the C-2 layer 132 is referred to as a back print. It is also possible to use one that has been subjected to back surface printing (printing is applied to the side laminated with the B-2 layer 122).

(Lamination of the C-1 layer by application of the adhesive composition forming the B-1 layer)
C which is a biaxially stretched polyester sheet by applying an adhesive composition for forming the B-1 layer 121 on the embossed design surface of the metal plate 150 laminated with a resin sheet of the A layer 110 having an embossed design on the surface. Although there is no restriction | limiting in the method of laminating | stacking -1 layer 131, It is limited to the method which can apply the adhesive composition which forms B-1 layer 121 by the thickness which the embossed design of A layer 110 surface is completely embedded. Here, the expression that the embossed design is completely buried is that the maximum height (Ry value) is the difference in height between the valley and the peak of the embossed design applied to the surface of the A layer 110 is X (μm). In such a case, the B-1 layer 121 is formed with a thickness exceeding at least X (μm). Furthermore, the thickness of the B-1 layer is 1.2 times or more, preferably 1.3 times or more the Ry value. If the coating thickness is 1.2 times or more of the Ry value, the C-1 layer 131 has the thinnest part (corresponding to the embossed design peak) and the thickest part (corresponding to the embossed design valley). The ratio of the thickness of the B-1 layer 121 does not significantly increase, and the difference in the amount of cure shrinkage in the thickness direction of the B-1 layer 121 at each portion does not differ greatly. Therefore, it is possible to sufficiently achieve the purpose of providing the C-1 layer 131 in which the degree of unevenness on the surface of the C-1 layer 131 is much gentler than the embossed design on the surface of the A layer 110. As a result, the smoothness of the surface of the C-2 layer 132, which is the outermost surface on the side having the designability of the designable laminated sheet-coated metal plate 100, can also be made sufficient. However, when the C-1 layer 131 is too thick, as in the case where the thickness of the A layer 110 is excessively thick, secondary workability such as folding workability of the resulting design-oriented laminated sheet-covered metal plate 100 can be obtained. Therefore, it is preferable to set the upper limit of the coating thickness of the B-1 layer 121 to about 1.5 times the Ry value.

As an example of a method of forming the B-1 layer 121 on the metal plate 150 laminated with the A layer 110 and laminating the C-1 layer 121 that is a transparent biaxially stretched polyester sheet, the roll laminating method shown in FIG. It can be preferably used.
In FIG. 2, 300 is a roll laminating laminating apparatus, 310 is a metal plate, 320 is an A layer sheet having an uneven design on the surface laminated on the metal plate, and 330 is an adhesive that forms the B-1 layer 121. Composition supply means (coat die), 340 is a puddle (bank) of the adhesive composition forming the B-1 layer 121, 350 is a biaxially stretched polyester sheet continuously supplied from the unwinding shaft, 360 is Lower laminating roll, 370 is an upper laminating roll, 380 is an ultraviolet irradiation device, 390a is an unwinding facility for continuously supplying a coil obtained by winding a metal plate on which an A layer is laminated, and 390b is a metal on which an A layer is laminated This is a winding facility for winding a sheet in which a B-1 layer is further formed on a plate. The adhesive composition liquid pool 340 is formed in front of the upper laminate roll 370 (the side to which the laminated metal plate 310 or the like is fed), and the amount of the adhesive composition liquid pool 340 to be retained is If the amount is small, it is difficult to degas bubbles entrained in the adhesive composition, and it is difficult to perform uniform coating. On the other hand, if the amount is too large, the adhesive composition protrudes from the end in the width direction and the yield of the adhesive composition deteriorates. Therefore, an appropriate amount can be supplied, and the capacity of the liquid pool 340 does not always vary greatly. It is preferable to provide such an adhesive composition supply mechanism.
The coating thickness of the B-1 layer 121 is the same as in the case of the normal roll laminating method, adjustment of the viscosity of the adhesive composition to be applied, adjustment of the line speed, setting of the roll gap, roll hardness, roll nip pressure. By adjusting or the like, the above-described preferable coating thickness is obtained.

  A laminate in which a C-1 layer 131 is laminated via an uncured B-1 layer 121 on a surface having an embossed design of the A layer 110 of a metal plate laminated with an A layer 110 by a laminating roll The ultraviolet light irradiation device 380 continuously irradiates ultraviolet rays from the upper side of the C-1 layer 131, thereby photopolymerizing and curing the adhesive composition of the B-1 layer 121. The light source of the ultraviolet irradiation device 380 may be any light source that can emit light having a wavelength range of 400 to 500 nm. For example, a high pressure mercury lamp, a metal halide lamp, a xenon lamp, an ultraviolet LED, a blue LED, a white LED, etc. The thing currently used for hardening of an ultraviolet curable adhesive is mentioned.

(Lamination of C-2 layer by application of adhesive composition forming B-2 layer)
The resin-coated metal plate having the C-1 layer 131 on the surface obtained as described above is caused by curing shrinkage of the B-1 layer 121 when irradiated with ultraviolet rays to cure the B-1 layer 121. Unevenness corresponding to the shape of the embossed design on the surface of the A layer 110 appears on the surface of the C-1 layer 131. Therefore, the smoothness of the surface of the C-1 layer 131 is insufficient. However, the degree of unevenness on the surface of the C-1 layer 131 is much gentler than the embossed design on the surface of the A layer 100. By covering the surface of the C-1 layer 131 with the C-2 layer 132 which is a biaxially stretched polyester sheet via the B-2 layer made of an adhesive composition, good surface smoothness is obtained. However, the coating method itself may be the same as the case where the C-1 layer 131 is coated via the B-1 layer 121.
However, the coating thickness of the B-2 layer 122 may be smaller than in the case of the B-1 layer 121, and the coating thickness is appropriately selected based on the thickness of the selected C-2 layer 132 and the degree of unevenness on the surface of the C-1 layer 131. Set conditions.

  The design-laminated laminated sheet-coated metal sheet having an internal embossed design according to the present invention has a relatively large difference in height between a valley portion and a mountain portion of the embossed design, while having an internal embossed design rich in stereoscopic effect, With respect to coexistence of the contradiction element of having a good surface smoothness with a specular glossiness (Gd value) of 0.8 or more, a resin layer having a thickness that is difficult to perform secondary processing such as bending processing conventionally. It is possible to achieve what was difficult to achieve with a thickness that can provide realistic workability, and for applications that require high design such as unit bath wall materials and unit bath ceiling materials. It can be used suitably.

  In order to describe the present invention more specifically and in detail, the following examples are given, but the present invention is not limited to these examples. In addition, the measurement standard and the test method of the physical property of the designable lamination sheet coating metal plate shown in the Example, the reference example, and the comparative example are as follows.

(Embossed depth of layer A / Ry)
Using a surface roughness meter (manufactured by Kosaka Laboratories, “Surfcoder” SE-40D), measured according to JIS B 0601 (1994), measured against the embossed design on the surface of layer A after being laminated to a metal plate And the maximum height Ry (μm) was determined. The results are shown in Table 1.

(Total thickness of resin layer)
The thickness of the designable laminated sheet-coated metal plate obtained in Examples, Reference Examples and Comparative Examples was measured with a dial gauge, and the value obtained by subtracting 0.45 mm, which is the nominal thickness of the metal plate, from the measured value was used as the resin layer. It was set as the total thickness. The measurement was carried out by removing 5 cm at both ends in the width direction and measuring at an interval of 1 cm in the width direction at arbitrary three locations in the longitudinal direction, and calculating an arithmetic average value. The results are shown in Table 1. Since the thickness of the metal plate itself varies from the nominal thickness, it is the total thickness of the resin layer as a guide only.

(UV curing adhesive thickness)
The total thickness of the resin layer determined above is obtained by subtracting the thicknesses of the A layer, the C-1 layer, and the C-2 layer, and the thickness of the UV curable adhesive (the coating thickness of the B-1 layer and the B-2 layer). ). The results are shown in Table 1. However, in addition to the fluctuation from the nominal value of the thickness of the metal plate, the thickness fluctuation of the C-1 layer, the C-2 layer, and the A layer is included, and the thickness of the A layer is flat without an uneven design by embossing. Therefore, it is the UV curable adhesive thickness as a guide only. Moreover, the measurement of each coating thickness of B-1 layer and B-2 layer is not implemented.

(Specular gloss Gd value)
The smoothness of the surface was measured using a portable sharpness gloss meter (manufactured by Japan Color Research Institute). The results are shown in Table 2. The measurement principle of the sharpness gloss meter is shown in FIG. FIG. 3A is a diagram schematically showing the configuration of the sharpness gloss meter. FIG. 3B is an enlarged view of the test pattern. In FIG. 3, reference numeral 210 denotes a sample (designable laminated sheet-coated metal plate), 220 denotes a test pattern, 230 denotes a light source, 240 denotes a reflecting mirror, 250 denotes an eyepiece, and a broken line arrow denotes an optical path.
As shown in FIG. 3A, the test pattern 220 illuminated by the light source 230 is reflected on the surface of the sample 210 via the reflecting mirrors 240 and 240. Further, the test pattern 220 reflected on the sample 210 from the eyepiece tube 250 can be seen through the reflecting mirrors 240 and 240. At this time, the higher the smoothness of the surface of the sample 210, such as a mirror surface, the more distinct the number of the test pattern 220 (see FIG. 3B) can be identified.
In Examples, Reference Examples, and Comparative Examples, the outermost surface on the resin layer side of the decorative laminated sheet-covered metal plate (in the Examples and Reference Examples, the outer surface of the C-2 layer. In the Comparative Examples, the C-1 layer The sharpness of the image reflected by the outer surface of the resin layer is measured, and the degree of smoothness of the outermost surface on the resin layer side is determined. Generally, when the Gd value (sharpness gloss value) obtained by the measurement is 0.8 or more, it is determined that the surface has good surface smoothness.

(Design of internal embossing)
Since no method for quantitatively evaluating the design feeling of the internal embossing was found, the sensory evaluation was made by visual observation. The results are shown in Table 2. Cut the sheet metal sheet with a designable laminated sheet with an internal embossing design into a size of 24cm x 24cm, attach it to the wall of a normal office with double-sided tape, and turn on the indoor fluorescent lamp at night when no external light enters. Observed by humans and averaged the evaluation results.
A case where it was judged that a sufficient sense of depth and three-dimensionality was felt and had a high-class design feeling was designated as “◯”, and among them, those having excellent depth and three-dimensionality were designated as “◎”. The case where the sense of depth and three-dimensionality was poor and a high-class feeling could not be felt was designated as “x”.

(Processability evaluation Bending processability)
The processability evaluation of the designable laminated sheet-coated metal plate was performed using a screw bending test apparatus. The results are shown in Table 2. FIG. 4 shows a schematic diagram of a screw bending test apparatus. FIG. 5 is a schematic diagram for explaining 180-degree bending (2T bending) using a screw bending test apparatus.
First, samples of 50 mm × 150 mm are cut out from the length direction and the width direction of the design-oriented laminated sheet-covered metal plate having an internal embossed design, and the laminated sheet is sandwiched with a round bar 460 having a diameter of 4 mm using a manual folding machine. A sample (preliminary bending test piece 450 as shown in FIG. 5 (a)) was produced that was folded back at 180 degrees with an inner radius of 2 mm so that the surface covered with the outer surface was on the outside.
The preliminary bending test piece 450 was subjected to 180 degree bending (2T bending) using a screw bending test apparatus 400. The screw bending test apparatus 400 (FIG. 4) includes an upper mold lifting / lowering handle 410, an upper mold lifting / lowering screw 420, an upper mold installation portion 430, and a lower mold installation portion 440. The upper mold lifting screw 420 is rotated by manually turning the upper mold lifting screw 410 provided on the upper mold lifting screw 420, and accordingly, the upper mold installation portion provided at the lower end of the upper mold lifting screw 420. 430 moves downward.
Further, as shown in the enlarged view of the 180-degree bent portion in FIG. 5B, the upper mold installation portion 430 is provided with a 180-degree bending upper mold 470, and the lower mold installation portion 440 is 180 degrees. A bending lower mold 480 is provided. Then, by operating the upper mold lifting handle 410, the 180-degree bending upper mold 470 provided in the upper mold installation portion 430 is moved downward, and the test piece 450 is moved between the 180-degree bending lower mold 480. The test piece 450 is bent by sandwiching with (FIG. 5C).
The test piece 450 is installed so that the surface covered with the laminated sheet becomes the outer surface after being bent, the test apparatus 400 is placed in a temperature-controlled room maintained at 23 ° C., and the measurement test piece is also 1 at 23 ° C. It is used for the test after being kept for more than an hour. 2T bending is a bending test in which the inner diameter of the bending is twice the thickness of the metal plate. In order to perform 2T bending, the pre-bending test piece 450 created above is overlapped with two holding plates 490 cut out from a metal plate having a thickness of 0.45 mm and sandwiched inside the pre-bending test piece 450 The upper mold 470 was lowered and the required bending was performed.
The surface state of the laminated sheet in the bent part is visually judged. If the resin layer is cracked or delaminated, it is judged that the resin layer has no practical workability. Although it was not, a case where an extremely fine crack occurred or a case where slight delamination occurred was evaluated as “Δ”, and a case where these abnormalities were not recognized was evaluated as “◯”.

(Pencil hardness test)
According to “JIS K 5600-5-4: 1999, paint general test method—Part 5: Mechanical properties of coating film—Section 4: Scratch hardness (pencil method)” The surface hardness was evaluated. The results are shown in Table 2. A jig capable of drawing in a temperature-controlled room at 23 ° C. with a load of 9.8 N while maintaining a 45 ° angle with respect to the surface of the laminated sheet side of the laminated sheet coated with a designable laminate cut to 80 mm × 60 mm Was drawn, and the surface state of the laminated sheet of the portion was visually determined. The case where the B pencil was not damaged at all was evaluated as “◯”, and the case where the B was scratched at all but the 2B pencil was not damaged at all was evaluated as “Δ”.

(Creation of A layer sheet having an embossed design on the surface)
Table 1 shows the sheet thicknesses of the A layer used in Examples, Reference Examples and Comparative Examples. Two co-axial biaxial kneading extruders ("TEX-65" manufactured by JSW) with venting devices at two locations with a cylinder diameter of φ65mm and bi-directional biaxial kneading with vent devices at two locations with a cylinder diameter of φ37mm Using a total of three extruders (“TEM-37” manufactured by Toshiba Machine Co., Ltd.), the resin that has flowed out of the T-die is taken up by a casting roll (take-off roll) by a coextrusion film forming method using a feed block method. A sheet of layer A consisting of three layers was prepared by a general method. The cylinder set temperature of the extruder is 200 ° C. on the feed side and 250 ° C. on the base side, and the same applies to each extruder. The T die set temperature was 250 ° C. as a reference, and the temperature setting in the width direction was finely adjusted as appropriate according to the state of film formation such as thickness distribution. The set temperature of various connecting conduits and feed block parts is also 250 ° C.
The breakdown of the three layers is the surface on the side laminated with the C-1 layer through the B-1 layer, and the resin layer on the side to which the embossed design is applied (referred to as the A1 layer) is homogenous. A layer containing 1.5 parts by mass of pearl mica pigment in 90 parts by mass of polybutylene terephthalate resin and 10 parts by mass of PETG resin. As an intermediate layer (A2 layer), 60 parts by mass of homopolybutylene terephthalate and a layer containing 2.0 parts by mass of carbon black pigment in 40 parts by mass of PETG resin. As the resin layer (referred to as the A3 layer) on the side laminated on the metal plate, the layer is composed of 25 parts by mass of homopolybutylene terephthalate and 75 parts by mass of PETG resin and does not contain a pigment component.
Regarding the A layer having a thickness of 120 μm, the extrusion amount is set so that the A1 layer is 30 μm, the A2 layer is 70 μm, and the A3 layer is 20 μm. In the A layer having a layer of 30 μm, an A2 layer of 140 μm, an A3 layer of 30 μm and a thickness of 260 μm, the coextrusion is performed so that the A1 layer is 30 μm, the A2 layer is 180 μm, and the A3 layer is 50 μm.

The temperature of the casting roll is adjusted by circulating water at 20 ° C., and the embossed wood grain is basically the same design with the maximum height (Ry) of 55 μm, 95 μm, and 138 μm on the surface. It is a surface-treated metal roll having a diameter of 400 mm. The molten resin having a laminated structure flowing down from the T die is extruded so that the side on which the A1 layer is formed becomes the casting roll side, and an embossed design is given to the surface. A silicone rubber touch roll adjusted to a surface temperature of about 40 ° C. by circulating water was brought into contact with the side on which the A3 layer was formed. The sheet flow speed (film forming speed) at the time of leaving the casting roll was 15 m / min.
As described above, when an embossed design having relatively concavity and convexity is imparted simultaneously with extrusion film formation, it becomes difficult to measure the actual thickness of the sheet. Therefore, the film was formed in advance using a casting roll having a smooth mirror surface. In this case, the thickness of the A layer is measured, and the sheet thickness of the A layer shown in Table 1 is that when the embossed design is not applied. In this case, the other conditions such as the discharge amount of the extruder, temperature setting, etc. were formed using a casting roll engraved with an emboss to form the A layer consisting of three layers used in the examples, reference examples and comparative examples of the present invention. Same as if you want to.

  In addition, for the A layer emboss depth of 36 μm and 165 μm in Table 1, a casting roll engraved with the same design of wood grain embossing could not be prepared, so the vertical x horizontal size was 26 cm. The surface of a flat plate press plate of 26 cm is embossed and engraved, and the A-layer sheet formed using a casting roll having a smooth mirror surface is heated using a hydraulic press. -Embossed design is given by pressurization.

The raw materials used for forming the A layer are as follows.
PETG resin: “Easter PET-G · 6763”, manufactured by Eastman Chemical Company, the dicarboxylic acid component is terephthalic acid, about 30 mol% of the diol component is 1.4-cyclohexanedimethanol and about 70 mol% is It is a substantially amorphous copolymerized polyethylene terephthalate resin which is ethylene glycol. The glass transition temperature is 78 ° C., and no melting point is observed.
Homopolybutylene terephthalate resin: “Novaduran 5020H”, a polybutylene terephthalate (homo PBT) resin manufactured by Mitsubishi Engineering Plastics. I. V. It is a standard grade for extrusion film formation with a value of 1.2, and its melting point is 225 ° C.
Pearl mica pigment: “DM-635R” is a pearlescent pigment having a mica surface coated with titanium dioxide in which 90% by mass of the total particles manufactured by Dia Kogyo Co., Ltd. are in the range of 5 to 15 μm.

(Lamination of layer A to metal plate)
A galvanized steel sheet (thickness: 0.45 mm) with a roll coater is applied to a polyester adhesive generally used for a polyvinyl chloride coated metal sheet so that the adhesive film thickness after drying is about 2 μm to 4 μm. ), Then drying and heating the coated surface with a hot air heating furnace and an infrared heater, setting the surface temperature of the steel sheet to 240 ° C., and immediately using the roll laminator, the sheet of layer A produced above Was coated so that the side to which the embossed design was applied was the surface side, and was cooled with water, whereby a metal plate having a surface coated with the sheet of layer A having the embossed design was produced. The type and application conditions of the adhesive used for laminating the A layer and the steel plate (metal plate) are the same in all Examples, Reference Examples and Comparative Examples. In addition, the emboss depth (Ry value) of the A layer described in Table 1 is measured after laminating the sheet of the A layer on the steel plate.

(C-1 layer coating via B-1 layer, C-2 layer coating via B-2 layer)
An ultraviolet curable adhesive is applied to the surface provided with the embossed design of the resin-coated metal plate having an embossed design on the surface created above to form a B-1 layer, and through the B-1 layer When the biaxially stretched polyester sheet (C-1 layer) is coated and the B-1 layer is cured by irradiating ultraviolet rays from the C-1 layer side, the roll laminate method shown in the schematic diagram of FIG. 2 is applied. Using the aligning apparatus 300, the following method was used. An unwinding facility 390a for continuously supplying a coil wound up of a metal plate laminated with an A layer, and an embossed design of the metal plate laminated with the A layer supplied from the unwinding device 390a is provided on the surface. , Supply means (coat die) 330 of the adhesive composition for forming the B-1 layer, a series of equipment such as a heating tank for supplying the adhesive composition, a constant supply pump, and the A layer on the metal plate A pair of laminating rolls 360 and 370 for laminating a biaxially stretched polyester sheet (C-1 layer) via the adhesive composition coated on the surface, an ultraviolet irradiation device 380 disposed immediately thereafter, a resin coating Necessary facilities such as a metal plate winding device 390b were arranged to continuously form the B-1 layer and laminate the C-1 layer. The role of the coat die 330 is to supply an adhesive composition so that an appropriate amount of the bank 340 is always formed on the entry side of the laminate rolls 360 and 370, and the coating accuracy as an original coater is not required. From this point, even if the adhesive composition was supplied from the coat die 330 to the surface of the A layer where the embossed design exists, no particular problem occurred.

The coating thickness of the B-1 layer is the same as in the case of a normal roll laminating method, adjusting the viscosity of the adhesive composition to be applied, adjusting the line speed, setting the roll gap, adjusting the roll hardness and roll nip pressure. In this example, reference example and comparative example, the viscosity of the adhesive composition, the gap of the laminate roll, the roll hardness, and the roll nip pressure are all the same, and the line speed is 3 m / min. By adjusting between ˜8 m / min, the coating thickness of the B-1 layer is approximately 1.3 to 1.5 times the maximum height (Ry value) of the unevenness due to the embossing of the A layer. The coating was carried out. In Reference Example 3 only, the B-1 layer is coated with a thickness that does not allow the unevenness of the embossed design of the A layer to be completely produced.
After the C-1 layer is coated via the B-1 layer, the resin-coated metal plate is continuously put into the ultraviolet irradiation device 380, and a high-pressure mercury lamp (made by Ushio Electric Co., Ltd. : UVC-5035 / IMNLC6-HGO) was used to irradiate with ultraviolet rays until the total irradiation amount became 340 mJ / cm ² , the adhesive composition of the B-1 layer was cured, and the lamination of the C-1 layer was integrated And was wound into a coil shape by the winding equipment 390b. In addition, for Reference Example 3 in which an embossed design was given by a pressing machine with a cutting plate, a biaxially stretched polyester sheet having a thickness of 50 μm was used as the carrier sheet, and the embossed design was given to the surface of 24 cm × 24 cm on the carrier sheet. The metal plate provided with the A layer is put into a bonding apparatus in a state of being temporarily fixed with a fine adhesive tape.

The resin-coated metal plate coated with the C-1 layer was coated with the C-2 layer via the B-2 layer by the same procedure. However, in Comparative Examples 1 to 5, the coating of the biaxially stretched polyester sheet has a conventional configuration of only one layer.
When coating the C-2 layer, the line speed was unified at 1 m / min in all Examples and Reference Examples. Accordingly, in any case, the B-2 layer is thinner than the B-1 layer. The composition forming the B-2 layer is the same as that used for the B-1 layer, and the biaxially stretched polyester sheet for the C-2 layer is the same as that used for the C-1 layer. Used. Therefore, for the C-2 layer that forms the outermost surface of the designable laminated sheet-coated metal plate, the easy-adhesion treatment is performed on both sides, but from the viewpoint of surface contamination resistance, etc. Originally, it is preferable to prepare a biaxially stretched polyester sheet that has been subjected to easy adhesion treatment only on one side.
Table 1 shows the thickness of the biaxially stretched polyester sheet used as the C-1 layer and the C-2 layer.

The contents of the adhesive composition constituting the B-1 layer and the B-2 layer are as follows.
UV curable adhesive (100 parts by mass): “New Frontier” R-1213 (Daiichi Kogyo Seiyaku Co., Ltd.) terminal acrylate-modified urethane prepolymer of about 50% by mass and acrylate monomer acryloylmorpholine of about 50 A non-yellowing ultraviolet curable adhesive having a glass transition temperature (Tg) of about −39 ° C., comprising a mixed composition of mass%.
Photopolymerization initiator (2 parts by mass): Irgacure 184 (manufactured by Ciba Specialty Chemicals).

The biaxially stretched polyester sheets used for the C-1 layer and the C-2 layer are as follows.
-"Tetron" SG-P2: Biaxially stretched polyethylene terephthalate resin film manufactured by Teijin, standard grade, each having a thickness of 25 µm and a thickness of 25 µm, and both surfaces easy adhesion treatment products.
"Tetron" HS-98: a biaxially stretched polyethylene terephthalate resin film manufactured by Teijin Co., Ltd., a highly transparent grade, a thickness of 75 [mu] m, 100 [mu] m and 125 [mu] m.

(Evaluation results)
From Table 2, the following evaluation results were obtained.
At the stage where the embossed design surface of the sheet A layer of the resin-coated metal plate being prepared by the above method is coated with the C-1 layer via the B-1 layer, before being put into the ultraviolet irradiation device (lamination roll) When the surface state immediately after exiting was observed, all of the cases except Reference Example 4 in which the coating thickness of the UV curable adhesive (B-1 layer) was thin with respect to the maximum height (Ry value) of the embossing were very It had a smooth surface. When the same sample was observed when exiting the ultraviolet irradiation device, the smoothness of the surface of the C-1 layer was lost, except for Comparative Example 5, to some extent. It was determined that the reason why the smoothness of the surface could not be ensured by one-layer coating of the C-1 layer (when the C-2 layer was not coated) was curing shrinkage in the thickness direction of the ultraviolet curable adhesive.

Comparative Example 1 was prepared by a method of coating only one layer of a conventional biaxially stretched polyester sheet. The coating thickness of the UV curable adhesive (B-1 layer) was the same as in Example 5. However, satisfactory surface smoothness (Gd value of 0.8 or more) has not been obtained. Moreover, when surface smoothness was low, it turned out that the feeling of depth of an internal embossing design and a three-dimensional effect also become scarce.
Comparative Example 2 has the same configuration as Comparative Example 1, and is a case where the coating thickness of the UV curable adhesive (B-1 layer) is further increased, and the surface smoothness is somewhat improved, but is sufficient. It can't be said that it is a good thing. As a result, the design of the internal embossed design remains low.
In Comparative Example 3, the coating of the biaxially stretched polyester sheet is also only one layer, and the coating thickness of the UV curable adhesive (B-1 layer) is increased by increasing the maximum height of the emboss. Nevertheless, satisfactory surface smoothness was not obtained.
In Comparative Example 4, the maximum height of the embossment is further increased, so that the coating thickness of the ultraviolet curable adhesive (B-1 layer) is increased and at the same time the biaxially stretched polyester sheet (C-1) to be coated Although a thick layer is used as the layer), the smoothness of the surface is still poor, and even though the layer A having deeper embossing (maximum embossing height is large) is used, a sense of depth and solidness I couldn't get a good evaluation about the feeling. In addition, since the thickness of the resin layer of the resin-coated metal plate has become considerably thick, the bending workability is hindered.
Comparative Example 5 is a case where the embossed design is shallow, and good smoothness is obtained even by a conventional configuration and manufacturing method. However, since the embossing was too shallow, the design feeling of the internal embossing was clearly insufficient.

Reference Example 1 is based on the configuration of the present invention in which two layers (C-1 layer and C-2 layer) are coated with a biaxially stretched polyester sheet. When the biaxially stretched polyester sheet having a relatively thin thickness is used as the C-2 layer, which finally becomes the outermost layer of the designable laminated sheet-coated metal plate, the coating thickness of the UV curable adhesive is embossed. Regardless of the thickness sufficient to fill the design, the surface smoothness was low and the surface hardness was low. As the biaxially stretched polyester sheet used for the C-2 layer, it is judged that it is easier to obtain good smoothness by using a slightly thicker one.
Reference Example 2 uses the A layer having the same embossed height as Reference Example 1, but the case where the thickness of the C-1 layer, which is the biaxially stretched polyester sheet to be coated first, is thin. It is estimated that the surface smoothing effect by the first coating was insufficient, and the surface smoothness after the C-2 layer coating was also poor. As for the C-1 layer, it is judged that the use of a biaxially stretched polyester sheet having a slightly thicker thickness makes it easier to improve the smoothness of the surface of the final outermost layer C-2. The Since the C-2 layer itself was thick, there was no problem with the surface hardness.

Reference Example 3 is a case where an A layer having deeper embossing is used, and both the C-1 layer and the C-2 layer use a relatively thick biaxially stretched polyester sheet. I couldn't get it. Moreover, since the smoothness of the surface is lowered, a good evaluation result is not obtained with respect to a sense of depth and a three-dimensional effect while giving a deep internal embossed design. Furthermore, the processability is somewhat poor, and if the thicknesses of the B-1 layer, the B-2 layer, the C-1 layer, and the C-2 layer are made thicker, the surface smoothness becomes deep, Although the three-dimensional effect may be improved, it is not preferable from the viewpoint of ensuring the minimum workability as a designable laminated sheet-coated metal plate even when using the configuration and production method of the present invention.
In Reference Example 4, as the calculated value of the coating thickness of the UV-curable adhesive, it appears that the coating thickness is thicker than the embossed design on the surface of the A layer, but B formed for coating the C-1 layer. Considering only the thickness of the -1 layer, it is considered that the coating is thinner than the embossed design. As described above, the surface of the C-1 layer immediately after leaving the laminate roll after coating the C-1 layer Asperities corresponding to the embossed design were observed. In this case, it is considered that the surface smoothing effect due to the application of the C-1 layer was insufficient, and the surface of the final outermost layer C-2 could not be smoothed.

  On the other hand, all of the embodiments of the present invention can have both good surface smoothness and an internal embossed design rich in depth and stereoscopic effect. However, in Example 1 using a biaxially stretched polyester sheet having a slightly thin thickness as the C-2 layer which is the outermost surface coating, the surface hardness is insufficient, and Example 11 having relatively deep embossing. , 12, the surface smoothness is good, but the bending workability is poor. About Examples 8-10 which use embossing shallower than these, in the evaluation of the design feeling of internal embossing, it has become the result which is not particularly different from Examples 11 and 12, and the maximum height of the embossed design is appropriate. In addition, it is considered preferable to balance the workability as a designable laminated sheet-coated metal plate.

In Example 8, the biaxially stretched polyester sheet of the C-2 layer, which is the outermost layer, is a slightly thick sheet, and the bending workability is also deteriorated. In Examples 9 and 10 using the thinner C-2 layer, there is no problem in workability, and the surface hardness is also a sufficient level, so that the workability is good. Therefore, it can be said that it is preferable to use a C-2 layer sheet having a thickness of 100 μm or less.
About the comparative example 5 created with the conventional manufacturing method, favorable surface smoothness is obtained, and it can be said that it is not necessary to dare to use the structure and manufacturing method of this invention in the case of this degree of embossed design. That's right. However, the design feeling of the internal embossing has not been evaluated well because the embossing is too shallow.

  While the present invention has been described in connection with embodiments that are presently the most practical and preferred, the present invention is not limited to the embodiments disclosed herein. Rather, it can be changed as appropriate without departing from the scope or spirit of the invention that can be read from the claims and the entire specification, and can be appropriately changed, and the design-laminated sheet-covered metal plate having an internal embossed design accompanying such change, the design-oriented laminate It should be understood that the manufacturing method of the sheet-coated metal plate and the unit bus member using the design-laminated laminated sheet-coated metal plate are also included in the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 100 Designable lamination sheet coating metal plate which has internal embossing design 110 Sheet | seat which has the uneven | corrugated design by embossing on the surface (A layer)
111 Layer including glitter pigment in layer A consisting of two layers 112 Layer including pigment for imparting coloring design and concealing property within layer A consisting of two layers 121 Composition including ultraviolet curable adhesive Layer made of material (B-1 layer)
122 Layer (B-2 layer) made of a composition containing an ultraviolet curable adhesive
131 Transparent biaxially stretched polyester film layer (C-1 layer)
132 Transparent biaxially stretched polyester film layer (C-2 layer)
DESCRIPTION OF SYMBOLS 140 Adhesive layer 150 Metal plate 210 Sample 220 Test pattern 230 Light source 240 Reflector 250 Eyepiece tube 300 Roll laminating laminating apparatus 310 Metal plate 320 Sheet of layer A having an uneven design on the surface laminated to the metal plate 330 Adhesion Agent supply means (coat die)
340 Puddle of adhesive composition (bank)
350 Biaxially stretched polyester sheet continuously fed from the unwinding shaft 360 Lower laminating roll 370 Upper laminating roll 380 Ultraviolet irradiation device 390a Unwinding equipment 390b Winding equipment 400 Screw bending tester main body 410 Upper mold lifting handle 420 Upper Mold lifting screw 430 Upper mold installation part 440 Lower mold installation part 450 Pre-bent test piece 460 Round bar 4 mm in diameter 470 180 degree bending upper mold 480 180 degree bending lower mold 490 Holding plate

Claims (4)

A design laminate sheet-covered metal plate comprising a metal plate and a laminate sheet covering the metal plate,
The laminated sheet is
The sheet (A layer) which is provided on the most metal plate side and is made of a composition containing a thermoplastic resin, and which has an uneven design by embossing on the surface,
A layer (B-1 layer) formed on the A layer with a thickness that fills the uneven design of the A layer, comprising a composition containing an ultraviolet curable adhesive,
A transparent biaxially stretched polyester sheet layer (C-1 layer);
A layer (B-2 layer) comprising a composition containing an ultraviolet curable adhesive;
A transparent biaxially stretched polyester sheet layer (C-2 layer);
In the order listed.
The design laminated sheet covering metal plate whose mirror surface glossiness (Gd value) measured about the surface of the said C-2 layer is 0.8 or more.   The thickness of the C-1 layer is 25 μm or more and 75 μm or less, the thickness of the C-2 layer is 50 μm or more and 100 μm or less, and the maximum height of the concavo-convex design by embossing applied to the surface of the A layer (Ry 2. The designable laminated sheet-coated metal sheet according to claim 1, wherein the value is 45 μm or more and 150 μm or less. A step of laminating a sheet having a concavo-convex design by embossing on the surface (A layer), which is composed of a composition containing a thermoplastic resin, on one surface of a metal plate;
Applying a composition containing an ultraviolet curable adhesive on the A layer to form an adhesive layer (B-1 layer) having a thickness to fill the uneven design of the A layer;
Laminating a transparent biaxially stretched polyester sheet layer (C-1 layer) on the B-1 layer;
Irradiating ultraviolet rays from the C-1 layer side to cure the B-1 layer;
Applying a composition containing an ultraviolet curable adhesive on the C-1 layer to form an adhesive layer (B-2 layer);
Laminating a transparent biaxially stretched polyester sheet layer (C-2 layer) on the B-2 layer;
Irradiating ultraviolet rays from the C-2 layer side to cure the B-2 layer;
Including
The manufacturing method of the designable lamination sheet coating metal plate whose mirror surface glossiness (Gd value) measured about the surface of the said C-2 layer is 0.8 or more.   A unit bath member comprising the designable laminated sheet-coated metal plate according to claim 1.

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