JP2012171158A - Laminate sheet, laminate sheet-coated metal plate, and screen board - Google Patents

Abstract

[PROBLEMS] To combine a characteristic as a reflection type screen and a characteristic as a white board, excel in emboss transferability, suppress emboss return and aged light yellowing, and crack by bending after metal plate lamination. Providing laminated sheets that can prevent cracks and cracks, laminated sheet-coated metal plates, and screen boards.
A layer 10 having an ethylene-tetrafluoroethylene copolymer resin as a main component and having a thickness of a predetermined value or more, and a B layer having a polycarbonate resin containing a structural unit derived from a sorbitol derivative as a main component and a thickness of a predetermined value or more. A layer 20 and a C layer 30 containing a predetermined amount or more of a predetermined PBT resin and a predetermined PTT resin in total, and the B layer is arranged between the A layer and the C layer. A laminated sheet-coated metal plate 300A obtained by laminating the laminated sheet as a laminated sheet 100A.
[Selection] Figure 1

Description

  The present invention is suitable for a screen board having both a function as a reflective screen for a video projection device such as a liquid crystal projector and a video projector and a function as a white board capable of repeatedly performing writing and erasing with a white board marker. The present invention relates to a laminated sheet, a laminated sheet-coated metal plate, a screen board, and the like.

Conventionally, at conferences, materials created by OHP etc. are projected onto the screen, so that information materials can be shared with attendees, and at the same time, the contents of the discussion can be written on a large sheet of paper affixed to the wall. It was common to carry out. In recent years, projectors that can be connected to a personal computer and directly project a personal computer screen have become widespread, and the price of large-capacity, small-sized memories has been reduced, and the use of the Internet on business trips due to the diversification of Internet connection methods. As a result, it has become possible to display an abundance of information that cannot be compared with a projector. In addition, sharing of information materials using projectors has become more substantial. In addition, the content of discussions at the conference can be input to the personal computer sequentially on the spot, so that information can be shared with everyone by displaying on the projector at the same time as recording in real time. As described above, the importance of the projector in the conference and the reflective screen for displaying the image projected therefrom is increasing.
On the other hand, depending on the content and style of the conference, it may be more efficient to write the content of the discussion by writing sequentially on paper suspended on the wall, or writing on the whiteboard in the same way. It is still essential.

  Therefore, in order to save space in the installation place of the reflective screen and the white board, it has been proposed that a single screen board has both functions. In general, a writing board such as a white board is required to have good writing performance with a whiteboard marker such as a water-based pen or an alcohol solvent pen and erasability with an eraser for whiteboard. On the other hand, the reflective screen is required to reflect light on the surface, and is required to have anti-glare properties in order to improve the visibility of the projected image. In particular, in recent reflective screens for projectors with high light illuminance, there is a problem of a phenomenon (so-called shining ball) in which an image becomes difficult to see due to the fact that the center where the light from the projector shines shines.

  For example, the sheet disclosed in Patent Document 1 is a sheet for a writing board and a sheet for a projection screen by providing a layer made of a polymer such as an aromatic polyester with a white pigment added on the surface of paper as a base material. The characteristics are obtained.

  In addition, the laminated films disclosed in Patent Document 2 and Patent Document 3 have a structure having a layer made of an extremely thin fluororesin on the surface layer, and consideration is given so as not to cause a problem in erasability as a whiteboard. ing. Also, an embossable layer is provided under the fluororesin sheet that is not easily embossed to prevent the occurrence of “shining balls” as a reflective screen, so that embossing can be applied from the surface side of the extremely thin fluororesin sheet. Even when the plate is pressed, it is possible to give surface irregularities to such an extent that no bright balls are generated.

JP-A-10-287091 International Publication No. 2006/121070 Pamphlet JP 2009-297973 A

  Since the sheet disclosed in Patent Document 1 limits the surface glossiness to a specific range, it is considered that the problem of so-called “shining balls” hardly occurs. However, since the surface layer is formed from an aromatic polyester-based resin containing an inorganic pigment, the erasability as a whiteboard may be insufficient. In addition, even when used indoors, the aromatic polyester-based resin gradually deteriorates yellow due to sunlight or the like incident from a window, but there is no description regarding measures for preventing such deterioration. Furthermore, on the premise that paper is used as the base material, emphasis is placed on the ease of construction and removal, such as mentioning a form in which an adhesive layer is provided on the back surface of the base material. That is, it is not considered to be used semi-permanently as a built-in wall material for offices and conference rooms, and is not suitable for such applications. Also, secondary processing such as bending is difficult.

  In the laminated films disclosed in Patent Document 2 and Patent Document 3, amorphous aromatic polyester resins such as PETG are exemplified as the embossable layer. Since these materials have a glass transition temperature of about 90 ° C. or less, emboss transfer itself is relatively easy. However, there is a risk of emboss return when laminated on a metal plate to form a laminated sheet-coated metal plate for a screen board. There is. In addition, since the fluororesin of the surface layer has a low ultraviolet absorptivity, it is exposed to sunlight or the like reaching the ground for a long time, so that amorphous such as PETG disposed on the substrate side of the fluororesin layer There is a possibility that the aromatic polyester-based resin may be yellowed over time, and there is room for improvement in this respect.

  Therefore, the present invention has (1) both a characteristic as a reflection type screen and a characteristic as a whiteboard, and (2) an excellent emboss transfer property in a general embossing apparatus, (3) It is possible to suppress the embossing return when laminating to a metal plate, (4) it is possible to suppress yellowing due to aged light deterioration, and (5) cracks in the bending process after laminating to the metal plate It is an object to provide a laminated sheet that can suppress the occurrence of cracks. Also provided is a laminated sheet-coated metal plate having the laminated sheet. Moreover, the screen board etc. which have this laminated sheet coating metal plate are provided.

  The present invention will be described below.

  1st aspect of this invention is a laminated sheet which has A layer, B layer, and C layer, Comprising: A layer contains ethylene-tetrafluoroethylene copolymer resin 50 mass% or more, and thickness is 15 micrometers or less. The layer B is a layer containing 50% by mass or more of a polycarbonate resin containing a structural unit derived from the dihydroxy compound represented by the formula (1) and having a thickness of 20 μm or more. A polybutylene terephthalate resin having a melting point of 215 ° C. or more and 235 ° C. or less, and a polytrimethylene terephthalate resin having a melting point of 215 ° C. or more and 235 ° C. or less, The total amount of the polytrimethylene terephthalate resin is 70% by mass or more and 100% by mass or less of the entire resin component constituting the C layer. , B layer is disposed between the A layer and the C layer.

  Here, the “sheet” in the present invention is a concept including both a range generally called “film” and a range called “sheet” with respect to the thickness. For convenience, in the present invention, both are referred to as a “sheet”. Accordingly, a sheet having a thickness generally called “film” such as “a fluororesin sheet having a thickness of 10 μm” is also called a “sheet”. In addition, “arranged between” means that a B layer exists between the A layer and the C layer, and between the B layer and the A layer and / or the C layer, other This means that the layer may be interposed. Here, examples of the “other layer” include an adhesive layer and a D layer described later.

  1st aspect of this invention WHEREIN: It is preferable that the glass transition temperature measured at a heating rate of 10 degree-C / min by the differential scanning calorimetry of the said polycarbonate resin which B layer contains is 100 degreeC or more and 155 degrees C or less. .

  1st aspect of this invention WHEREIN: It is preferable that the emboss is provided to the surface of A layer.

  In the first aspect of the present invention, it is preferable that at least one layer selected from the B layer and the C layer contains a white pigment.

  In the first embodiment of the present invention, the dihydroxy compound represented by the above formula (1) is 1,4: 3,6-dianhydro-D-sorbitol (hereinafter sometimes referred to as “isosorbide”). Something is preferable.

  In the first aspect of the present invention, a D layer is disposed between the B layer and the C layer, and the D layer comprises an amorphous or low crystalline aromatic polyester resin, and the D layer comprises It is good also as a structure which is a layer which contains 60 mass% or more with respect to the whole resin component to comprise, and contains a white pigment.

  In the present invention, the resin being “amorphous” means that, in differential scanning calorimetry (DSC) of the resin, no crystal melting peak is observed when the resin is heated at a heating rate of 10 ° C./min. . In addition, the resin having “low crystallinity” means that a crystal melting peak is observed when the resin is heated at a heating rate of 10 ° C./min in the differential scanning calorimetry (DSC) of the resin. It means that the heat of crystal melting (ΔHm) corresponding to the crystal melting peak is 10 J / g or less.

  In the first aspect of the present invention having the D layer, the aromatic polyester resin contained in the D layer is a polyester resin obtained by copolymerizing a terephthalic acid component and a diol component, The component preferably contains 20 mol% or more and 40 mol% or less 1,4-cyclohexanedimethanol and 60 mol% or more and 80 mol% or less ethylene glycol based on 100 mol% of the entire diol component.

  In the present invention, the “terephthalic acid component” means a component which gives the same structural unit as the structural unit derived from terephthalic acid when copolymerized with a diol component. In addition to terephthalic acid, dimethyl terephthalate, diethyl terephthalate It is a concept including terephthalic acid diesters such as terephthalic acid monoesters such as monomethyl terephthalate and monoethyl terephthalate; phthalic anhydride and the like.

  In the first aspect of the present invention having no D layer, the B layer and the C layer are preferably laminated and integrated by a coextrusion film forming method.

  In the first aspect of the present invention having the D layer, the B layer, the D layer, and the C layer are preferably laminated and integrated by a coextrusion film forming method.

  1st aspect of this invention WHEREIN: It is preferable that the 60 degree specular glossiness measured based on JISK7105 is 30% or less about the surface by the side of A layer.

  According to a second aspect of the present invention, there is provided a laminated sheet-coated metal plate, wherein the laminated sheet according to the first aspect of the present invention is laminated to a metal plate with the surface on the C layer side as an adhesive surface. is there.

  A third aspect of the present invention is a screen board, a white board, a reflective screen, or a building interior material having the laminated sheet-coated metal plate according to the second aspect of the present invention.

  In the present invention, “screen board” means an information medium that can be used as both a reflective screen and a white board. The “building interior material” means an interior material used for a part that is visible to a person inside the building. “Parts visible to a human being inside a building” include a wall surface, a ceiling surface, a floor surface, and the like of the building.

  According to the first aspect of the present invention, since the layers stacked in a predetermined order have a predetermined configuration, (1) both the characteristics as a reflective screen and the characteristics as a whiteboard are good. In addition, (2) excellent emboss transferability in a general embossing device, (3) can suppress the emboss return when laminating to a metal plate, and (4) yellowing due to light deterioration over time It is possible to provide a laminated sheet that can suppress the occurrence of cracks and cracks in the bending process after being laminated on a metal plate.

  According to the second aspect of the present invention, the laminated sheet according to the first aspect of the present invention is laminated on the metal plate in a predetermined direction, so that (1) the characteristics as a reflective screen and white Both the characteristics as a board are good, (2) it is possible to suppress yellowing due to aged light degradation, and (3) it is possible to suppress the occurrence of cracks and cracks in bending. It is possible to provide a laminated sheet-coated metal plate that can be easily subjected to secondary processing such as panel processing.

  According to the third aspect of the present invention, by having the laminated sheet-coated metal plate according to the second aspect of the present invention, (1) both the characteristics as a reflective screen and the characteristics as a whiteboard are good. In addition, (2) yellowing caused by age-related light deterioration can be suppressed, and (3) only when installed inside buildings where there are many windows, such as offices and conference rooms. Thus, a screen board, a white board, a reflective screen, and a building interior material that can be used for a long time even when they are built up can be provided.

(A) And (b) is sectional drawing which illustrates typically the layer structure before emboss provision of the lamination sheet of this invention. (C) And (d) is sectional drawing which illustrates typically the layer structure after emboss provision of the lamination sheet of this invention. Moreover, (e) and (f) are sectional views for schematically explaining the layer structure of the laminated sheet-coated metal plate of the present invention. It is a figure which illustrates typically the embossing apparatus generally used in order to provide an emboss design to the sheet | seat of a soft PVC.

  The present invention will be described below with reference to the drawings. In addition, the form shown below is an illustration of this invention and this invention is not limited to these forms. In the following, “A to B” means A or more and B or less unless otherwise specified.

In the following description, “Y whose main component is X” means that the mass ratio of X in Y is 50 mass% or more, and is a concept including 100 mass%.
Further, in the following description, “non-oriented” means that the laminated sheet was not intentionally subjected to an orientation treatment such as a stretching operation in order to impart some performance, and is cast during extrusion film formation. It does not mean that there is no orientation or the like generated by taking-up with a roll.

Fig.1 (a)-(d) is sectional drawing which illustrates typically the laminated constitution of the lamination sheet of this invention, and a lamination sheet covering metal plate. FIG. 1A shows a laminated sheet (100A) before embossing, which has three layers of an A layer (10), a B layer (20), and a C layer (30). FIG. 1B shows a laminated sheet (100B) before embossing, which has four layers of an A layer (10), a B layer (20), a D layer (40), and a C layer (30). Fig. 1 (c) shows a laminated sheet (200A) obtained by embossing the laminated sheet (100A) of Fig. 1 (a). FIG. 1D shows a laminated sheet (200B) obtained by embossing the laminated sheet (100B) shown in FIG. FIG. 1E shows a laminated sheet-covered metal plate (300A) obtained by laminating an embossed laminated sheet (200A). FIG. 1 (f) shows a laminated sheet-covered metal plate (300B) obtained by laminating an embossed laminated sheet (200B).
Hereinafter, each layer will be described.

<A layer (10)>
A layer (10) is a layer which has ethylene-tetrafluoroethylene copolymer resin as a main component. The content of the ethylene-tetrafluoroethylene copolymer resin in the layer A (10) is 50% by mass or more, preferably 70% by mass or more, more preferably 90% by mass or more, and may be 100% by mass. . Moreover, A layer is a layer located in the outermost surface of the lamination sheet of this invention, and the lamination sheet coating | coated metal plate of this invention. The surface of the A layer is a reflective screen surface on which an image projected from the projector is displayed, and at the same time, any content such as letters is written by a whiteboard marker, and the written content is erased by an eraser. .

The layer A (10) preferably has a small surface cohesive energy from the viewpoint of improving the erasability as a white board. Moreover, from the viewpoint of improving the bending workability of the resin-coated metal plate laminated with the laminated sheet, it is preferable that the resin component constituting the A layer (10) is made of a thermoplastic resin. In the present invention, by using ethylene-tetrafluoroethylene copolymer resin, which is a thermoplastic resin having a small surface cohesive energy, as a main component of the A layer, a good balance between printability and erasability as a whiteboard is achieved. Can be made.
As the ethylene-tetrafluoroethylene copolymer resin, known materials can be used without particular limitation. Examples of the ethylene-tetrafluoroethylene copolymer resin that can constitute the A layer include, for example, a product name “Aflon COP” manufactured by Asahi Glass Co., Ltd., a product name “Neofuron ETFE” manufactured by Daikin Industries, Ltd., and a product name “Tefzel manufactured by DuPont. Or the like.

  As described above, the A layer (10) has an ethylene-tetrafluoroethylene copolymer resin as a main component. However, the layer A contains other resins and additives as long as the surface cohesive energy is low and the bending workability is good, as well as the interlaminar adhesion with the layer B and the weather resistance described later. It may be.

The thickness of the A layer (10) in the present invention is important to be 15 μm or less, more preferably 10 μm or less, and particularly preferably 6 μm or less. Moreover, it is preferable that it is 2 micrometers or more, and it is especially preferable that it is 4 micrometers or more.
Since the ethylene-tetrafluoroethylene copolymer resin forming the A layer has a very high melting point of about 270 ° C., if the A layer is too thick, the upper limit of the heating temperature in a general embossing machine is about 200 ° C. On the other hand, emboss transfer becomes difficult.
Therefore, in the present invention, the A layer is made an extremely thin layer, and at the same time, as a lower layer of the A layer, a laminated sheet in which a B layer (20), which will be described later, is a layer excellent in emboss transferability. When the embossing plate is pressed from the surface on the A layer side, the A layer is also deformed following the deformation of the B layer, so that a good embossed transfer can be obtained on the surface of the A layer.
That is, when the thickness of the A layer is not more than the above upper limit value, the embossed transfer onto the surface of the A layer becomes good. Therefore, when used as a screen board, generation of “shining balls” can be suppressed, which is preferable.
In addition, since the ethylene-tetrafluoroethylene copolymer resin is softer than a polycarbonate resin having a specific structure which is a main component of the B layer described later, the scratch resistance of the laminated sheet is improved by the screen board. The thickness of the A layer is preferably not more than the above upper limit value from the viewpoint of making it satisfactory enough for practical use.
Moreover, it is preferable that the thickness of A layer is below the said upper limit from the point that an ethylene-tetrafluoroethylene copolymer resin is expensive.
On the other hand, the thickness of the A layer is preferably not less than the above lower limit value from the viewpoint of suppressing the occurrence of pinhole defects during extrusion film formation.

  As a method of providing the A layer (10) on the laminated sheet of the present invention, for example, a method of forming the A layer as a single layer sheet and laminating it with the B layer (20) described later in the later step, A method of forming a laminated sheet by coextrusion including the A layer can be used without particular limitation. However, from the viewpoint that the molding temperature is different between the A layer and other layers in the coextrusion, and that the equipment for molding the ethylene-tetrafluoroethylene copolymer resin needs to have corrosion resistance, A A method of forming the layer as a single-layer sheet and laminating it with the B layer described later in a later step is preferable.

  The method for forming the A layer as a single-layer sheet is not particularly limited. However, from the viewpoint of facilitating the handling of an extremely thin A layer having a thickness of 15 μm or less, for example, (1) Resin that forms an A layer from a T die on the carrier sheet using a stretched PET film or the like as a carrier sheet The composition is extruded, allowed to flow down, wound in a state where the A layer and the carrier sheet are temporarily adhered, and the carrier sheet temporarily adhered to the A layer is peeled off in the subsequent process, or (2) the A layer is constituted. Co-extrusion film formation with a resin composition that does not have adhesive properties (for example, polyolefin-based resin, etc.) is wound in a state of temporary adhesion, and the resin layer that is temporarily adhered to the A layer is peeled off in a later step. A method or the like can be preferably used.

As a method of laminating the A layer (10) with the B layer (20) described later in a later step, various known methods can be used without particular limitation. However, from the viewpoint of further strengthening the interlayer adhesion between the A layer and the B layer, an adhesive is used, and an adhesive layer (50) is provided between the A layer and the B layer for lamination. Is preferred.
In the case where an adhesive layer is provided between the A layer and the B layer, from the viewpoint of improving the emboss transfer property of the surface of the A layer by utilizing the good emboss transfer property of the B layer as described later, the A layer It is preferable that the adhesive layer used for laminating the B and B layers is as thin as possible.
As a preferred laminating method using an adhesive, a solvent-coated thermosetting adhesive is used, and the surface of the A layer on the side laminated with the B layer and / or the surface of the B layer on the side laminated with the A layer In addition, the adhesive is applied with a coater so that the dry film thickness becomes 1 μm to 3 μm, the solvent content is volatilized by heat drying, and then the A layer and the B layer are overlapped and bonded and laminated. The law can be exemplified. In the case of using the dry laminating method, from the viewpoint of maintaining the handleability of the A layer, the peelable carrier that is temporarily adhered to the A layer until the lamination of the A layer and the B layer by the dry laminating method is completed. It is preferable not to peel off the sheet.

  As the thermosetting adhesive used in the dry laminating method, an adhesive having an adhesive property with an ethylene-tetrafluoroethylene copolymer resin can be used without particular limitation. For example, it is possible to preferably use a type in which a polyester-based resin, a polyether-based resin, or the like is used as a main component and is cured with an isocyanate-based crosslinking agent. Among the dry laminating adhesives, it is more preferable to use an aliphatic adhesive from the viewpoint that there are few problems of yellowing due to ultraviolet rays. As an example of the aliphatic polyester-based adhesive main agent, the trade name “TM-K51” manufactured by Toyo Morton Co., Ltd. can be mentioned. By mixing the main agent and various isocyanate-based crosslinking agents in an organic solvent, A laminating adhesive can be obtained.

  However, the method of adhesion lamination of the A layer and the B layer is not limited to the above-described method, and a solvent-type or solvent-free ultraviolet curable adhesive, an electron beam / radiation curable adhesive, or the like is used. May be. In addition, the surface of the B layer on the side to be laminated with the A layer has an adhesive property with a fluorine-based resin and does not cause any special difficulties when performing co-extrusion film formation with the B layer. A method of applying a melt-adhesive resin layer by a coextrusion film forming method may be used. Also in these cases, from the viewpoint of improving emboss transferability, the thickness of the adhesive layer is preferably 1 μm to 3 μm in terms of dry film thickness.

As described above, the surface of the A layer is preferably provided with embossing from the viewpoint of preventing “shining balls” and ensuring good erasability.
As the embossing plate for matting for embossing the surface of the layer A, those used for finishing the surface of a decorative sheet or a metal sheet coated with a decorative sheet to a matte design can be used. This is the embossed version used for “Satin finish”. In the present invention, the A layer itself located on the outermost layer is a layer that does not soften to the extent that it can be embossed when heated by an embossing apparatus, and therefore, compared with a case where emboss transfer is performed on a general decorative sheet. The gloss value may be slightly increased, but by appropriately selecting the pitch and depth of the unevenness of the embossed plate itself, the shape of the surface finish, etc., a surface gloss value in a preferable range as described later can be obtained. Is possible.

The 60-degree specular gloss measured in accordance with JIS K7105 is preferably 30% or less for the layer A side surface of the laminated sheet of the present invention or the laminated sheet-coated metal sheet laminated with the laminated sheet. The 60 ° specular gloss is more preferably 25% or less, and particularly preferably 20% or less. The 60-degree specular gloss is preferably 7% or more, more preferably 10% or more, and particularly preferably 15% or more.
When the 60-degree specular gloss is less than or equal to the above upper limit value, the diffuse reflectivity on the surface of the layer A becomes high, and when the laminated sheet or the laminated sheet-coated metal plate is used for a screen board, a “shining ball” is generated. Can be suppressed. On the other hand, when the 60-degree specular gloss is equal to or higher than the above lower limit, the erasability when used as a whiteboard is good. Therefore, by making the surface of the layer A a surface having a 60-degree specular gloss in the above range, both the diffuse reflectance as a screen board and the erasability as a white board can be achieved at a good level. Can do.
For example, by adjusting the shape of the emboss transferred onto the surface by the method as described above, the 60-degree specular gloss can be in the above range.

<B layer (20)>
B layer (20) is a layer which has as a main component the polycarbonate resin containing the structural unit derived from the dihydroxy compound represented by following formula (1). In the B layer, the content of the polycarbonate resin containing a structural unit derived from the dihydroxy compound represented by the following formula (1) is 50% by mass or more, preferably 70% by mass or more, and more preferably 90% by mass. % Or more, and may be 100% by mass.
As described above, the B layer is a layer necessary for obtaining a good embossed transfer on the surface of the A layer, and is a layer for improving the heat resistance of the transferred emboss. In addition, by using a resin component having a low light yellowing property as the resin component constituting the B layer, the laminated sheet of the present invention and the laminated sheet-covered metal plate can suppress light yellowing over time. It is a layer to be applied.

  The dihydroxy compound represented by the above formula (1) is an ether diol that can be produced from a saccharide using a biogenic material as a raw material. In particular, isosorbide (1,4: 3,6-dianhydro-D-sorbitol) can be produced at low cost by hydrogenating and dehydrating D-glucose obtained from starch, and should be obtained in abundant resources. Is possible. For these reasons, isosorbide is most preferably used.

Examples of the dihydroxy copolymer component other than the dihydroxy compound represented by the formula (1) constituting the B layer polycarbonate resin include, for example, the aliphatic dihydroxy compounds described in International Publication No. 2004/111106 pamphlet, International Publication 2007 The alicyclic dihydroxy compound described in the / 148604 pamphlet can be mentioned. In other words, the general formula _{HO-C m H 2m -OH (} m is an integer from 2 to 12) can be exemplified and aliphatic dihydroxy compound represented by the alicyclic dihydroxy compound is not particularly limited.

  Among the aliphatic dihydroxy compounds, at least one dihydroxy compound selected from ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol is used. It is preferable to include.

  Among the alicyclic dihydroxy compounds, it is preferable to include a 5-membered ring structure or a 6-membered ring structure, and the 6-membered ring structure may be fixed to a chair type or a boat type by a covalent bond. By including a structural unit derived from such an alicyclic dihydroxy compound, the heat resistance of the obtained polycarbonate resin can be increased. The number of carbon atoms contained in the alicyclic dihydroxy compound is usually 70 or less, preferably 50 or less, and more preferably 30 or less.

The alicyclic dihydroxy compound containing the 5-membered ring structure or a 6-membered ring structure represented by the general formula HOCH ₂ -R ¹ -CH ₂ OH, or an alicyclic dihydroxy compound represented by ^HO-R 2 -OH (provided that , R ¹ and R ² can be exemplified by a cycloalkyl group having 4 to 20 carbon atoms or a cycloalkoxy group having 6 to 20 carbon atoms. Among these, cyclohexane dimethanol, tricyclodecane dimethanol, adamantanediol and pentacyclopentadecane dimethanol are preferable, and cyclohexane dimethanol or tricyclodecane dimethanol is most preferable in view of economy and heat resistance. These alicyclic dihydroxy compounds may be used alone or in combination of two or more.
Among cyclohexanedimethanol, 1,4-cyclohexanedimethanol, which is industrially easily available, is preferable.

  The content ratio of the structural unit derived from the dihydroxy compound represented by the above formula (1) in the polycarbonate resin constituting the B layer is preferably 30%, based on the total amount of the structural unit derived from the dihydroxy compound as 100 mol%. More than mol%, More preferably, it is 50 mol% or more, Preferably it is 90 mol% or less, More preferably, it is 80 mol% or less. By setting the content ratio of the structural unit derived from the dihydroxy compound represented by the above formula (1) to the lower limit value or more, coloring caused by the carbonate structure can be suppressed, and the visible light transmittance of the polycarbonate resin can be suppressed. It becomes easy to make better. Therefore, when the layer B (20) is a transparent layer and has a colored layer below it, the transparency of the layer B (20) can be improved. Further, when a colored pigment is added to the B layer (20) to form a colored layer, it is possible to easily obtain the desired color without being affected by the color derived from impurities. Moreover, by making the content rate of the structural unit derived from the dihydroxy compound represented by the said Formula (1) below into the said upper limit, only the structural unit derived from the dihydroxy compound represented by the said Formula (1) is polycarbonate. Compared to the case of forming a resin, it becomes easier to balance appropriate physical properties such as moldability, mechanical strength, and heat resistance.

In the polycarbonate resin constituting the B layer, the structural unit derived from the dihydroxy compound is derived from the structural unit derived from the dihydroxy compound represented by the above formula (1) and the aliphatic dihydroxy compound or the alicyclic dihydroxy compound. It is preferable to consist of a structural unit.
However, a structural unit derived from a dihydroxy compound other than the above may be contained in a small amount by copolymerization, polymer blending, or the like as long as the effect of the present invention is not significantly impaired. Thereby, it can be expected that heat resistance and moldability can be improved efficiently. The content is preferably 10 mol% or less, more preferably 8 mol% or less, and more preferably 6 mol% or less, based on the total amount of structural units derived from the dihydroxy compound as 100 mol%. Is more preferable.

  The glass transition temperature of the polycarbonate resin constituting the B layer is measured at a heating rate of 10 ° C./min by differential scanning calorimetry (DSC) according to JIS K7121, preferably 100 ° C. or more and 155 ° C. or less, more preferably 105 ° C. The temperature is 150 ° C. or lower, particularly preferably 110 ° C. or higher and 140 ° C. or lower. Further, the polycarbonate resin constituting the B layer usually has a single glass transition temperature. The glass transition temperature can be adjusted within the above range by appropriately adjusting the polymerization composition ratio of the polycarbonate resin.

  The elastic modulus of the polycarbonate resin changes significantly before and after the glass transition temperature. Therefore, by setting the glass transition temperature within the above range, embossing design by heat softening of the laminated sheet and fixing of the embossed pattern by subsequent cooling are facilitated, so that the emboss transferability is improved. Furthermore, by having a glass transition temperature within the above range, embossing heat resistance is also improved, and a general method for laminating a resin sheet to a metal plate for producing a laminated sheet-coated metal plate, that is, on the surface of the metal plate. Even after using a method of laminating a laminated sheet using a roll laminator or the like while maintaining the heated state after coating and baking the laminating adhesive, it is possible to suppress emboss return. That is, it can be set as the laminated sheet which can suppress the change of an embossing shape after lamination to a metal plate, and the laminated sheet covering metal plate which has this laminated sheet.

  The polycarbonate resin constituting the B layer can be produced by a generally performed polymerization method, and may be either a phosgene method or a transesterification method in which it reacts with a carbonic acid diester. Among these, a transesterification method in which the dihydroxy compound represented by the above formula (1) and other dihydroxy compounds are reacted with a carbonic acid diester in the presence of a polymerization catalyst is preferable. The transesterification method is a polymerization method in which a dihydroxy compound, a carbonic acid diester, a basic catalyst, and an acidic substance that neutralizes the catalyst are mixed to perform a transesterification reaction.

Examples of the carbonic acid diester include diphenyl carbonate, ditolyl carbonate, bis (chlorophenyl) carbonate, m-cresyl carbonate, dinaphthyl carbonate, bis (biphenyl) carbonate, diethyl carbonate, dimethyl carbonate, dibutyl carbonate, and dicyclohexyl carbonate. Of these, diphenyl carbonate can be suitably used.
The molecular weight of the polycarbonate resin containing the structural unit derived from the dihydroxy compound represented by the above formula (1) used in the present invention thus obtained can be represented by a reduced viscosity. The reduced viscosity is a value measured at a temperature of 20.0 ° C. ± 0.1 ° C. using methylene chloride as a solvent, adjusting the polycarbonate concentration to 0.60 g / dl precisely. The lower limit of the reduced viscosity is usually 0.30 dL / g or more, preferably 0.35 dL / g or more. The upper limit of the reduced viscosity is usually 1.20 dL / g or less, more preferably 1.00 dL / g or less, and still more preferably 0.80 dL / g or less. When the reduced viscosity of the polycarbonate resin is not less than the above lower limit value, it becomes easy to impart good mechanical strength to the molded product. Moreover, since it becomes easy to ensure the favorable fluidity | liquidity at the time of shaping | molding because the reduced viscosity of polycarbonate resin is below the said upper limit, it becomes easy to improve a moldability and productivity.

  The polycarbonate resin constituting the B layer is different from a general aromatic polycarbonate resin in which the structure derived from bisphenol A occupies a major proportion in the main chain, and absorbs light in the ultraviolet to near ultraviolet wavelength region, for example, a wavelength of 280 nm to 400 nm. Since it hardly occurs, it has excellent resistance to yellowing deterioration caused by receiving light in these wavelength ranges. Therefore, in order to prevent light yellowing of the B layer itself, it is not particularly necessary to add an ultraviolet absorber. However, when the B layer is used as a layer having visible light permeability without adding a color pigment, external light transmitted from the A layer side in the laminated sheet further passes through the B layer, and From the viewpoint of suppressing the deterioration of yellowing deterioration of the C layer and / or D layer, which is a layer disposed on the metal plate side from the B layer, an ultraviolet absorber is blended in the B layer (20). Is preferred.

As the ultraviolet absorber added to the B layer (20) as necessary, known ones such as various commercially available ones can be used without particular limitation. Especially, what is normally used for the addition to well-known aromatic polycarbonate resin can be used conveniently. For example, 2- (2′-hydroxy-5′-tert-octylphenyl) benzotriazole, 2- (3-tert-butyl-5-methyl-2-hydroxyphenyl) -5-chlorobenzotriazole, 2- (5 -Methyl-2-hydroxyphenyl) benzotriazole, 2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole, 2,2′-methylenebis (4-cumyl- Benzotriazole ultraviolet absorbers such as 6-benzotriazolephenyl); benzoxazine ultraviolet absorbers such as 2,2′-p-phenylenebis (1,3-benzoxazin-4-one); Hydroxyphenyls such as 6-diphenyl-1,3,5-triazin-2-yl) -5- (hexyl) oxy-phenol Azine ultraviolet absorber, and the like. The melting point of the ultraviolet absorber is particularly preferably in the range of 120 ° C to 250 ° C. When using a UV absorber with a melting point of 120 ° C or higher, the molded product surface becomes dirty due to a bleed-out phenomenon in which the UV absorber aggregates on the surface of the molded product over time, or when molding is performed using a die or a metal roll. Prevents bleed out of them and makes it easier to reduce and improve haze on the surface of the molded product.
More specifically, 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-3′-tert-butyl-5′-methylphenyl) -5-chlorobenzotriazole 2- [2'-hydroxy-3 '-(3 ", 4", 5 ", 6" -tetrahydrophthalimidomethyl) -5'-methylphenyl] benzotriazole, 2,2-methylenebis [4- (1, Benzotriazole-based UV absorbers such as 1,3,3-tetramethylbutyl) -6- (2H-benzotriazol-2-yl) phenol and 2- (2-hydroxy-3,5-dicumylphenyl) benzotriazole And hydroxyphenyltriazine-based ultraviolet absorbers such as 2- (4,6-diphenyl-1,3,5-triazin-2-yl) -5- (hexyl) oxy-phenol are preferably used. Among these, 2- (2-hydroxy-3,5-dicumylphenyl) benzotriazole, 2,2-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2H -Benzotriazol-2-yl) phenol, 2- (4,6-diphenyl-1,3,5-triazin-2-yl) -5- (hexyl) oxy-phenol are particularly preferred. These ultraviolet absorbers may be used alone or in combination of two or more.

In the laminated sheet of the present invention, it is preferable that at least one of the B layer (20) and the C layer (30) described later contains a white pigment. However, in the case where a D layer (40) described later is provided between the B layer and the C layer, the white layer is contained in the D layer so that neither the B layer nor the C layer contains a white pigment. It is good.
Various known pigments can be used as the white pigment. However, from the viewpoint of concealment, it is preferable that the main component is a titanium oxide pigment. The content of the titanium oxide pigment in the white pigment is 50% by mass or more, preferably 70% by mass or more, more preferably 90% by mass or more, and may be 100% by mass.
When a white pigment is included in the B layer (20), the color can be further adjusted by adding various inorganic and / or organic chromatic pigments.
When the white pigment is contained in the B layer (20), the white pigment content is preferably in the range of 20 to 60 parts by mass with respect to 100 parts by mass of the total resin constituting the B layer. More preferably, they are 25 mass parts-55 mass parts, More preferably, they are 30 mass parts-50 mass parts. By making the content of the white pigment within the above range, a white sheet suitable for use as a white board or a screen board, the laminated sheet-coated metal plate of the present invention, without impairing the formability of the laminated sheet of the present invention. It is easy to have a concealing property.

  In the B layer (20), various additives that may be generally added to the thermoplastic resin may be added in appropriate amounts as necessary, other than the ultraviolet absorber. The layer B (20) may be composed of a single layer as long as it is a layer mainly composed of the above-described polycarbonate resin. For example, the content of the dihydroxy compound represented by the formula (1) is A multilayer structure in which one or more layers made of a plurality of different polycarbonate resins are laminated may be used.

The thickness of the B layer (20) is important to be 20 μm or more, and more preferably 30 μm or more from the viewpoint of improving the emboss transferability of the laminated sheet. Furthermore, when only the B layer is used as the additive layer of the color pigment, it is particularly preferable that the thickness of the B layer is 40 μm or more from the viewpoint of providing a good color and concealing property by the laminated sheet.
The thickness of the B layer is preferably 120 μm or less, and particularly preferably 105 μm or less. By making the thickness of the B layer not more than the above upper limit value, it becomes possible to reduce the thickness while improving the secondary workability such as bending of the laminated sheet-coated metal plate.

<C layer (30)>
The C layer (30) is at least one of a polybutylene terephthalate (PBT) resin having a melting point of 215 ° C. or more and 235 ° C. or less and a polytrimethylene terephthalate (PTT) resin having a melting point of 215 ° C. or more and 235 ° C. or less. In which the total amount of the polybutylene terephthalate resin and the polytrimethylene terephthalate resin is 70% by mass or more and 100% by mass or less of the entire resin component constituting the layer.

  C layer has a role to prevent width shrinkage, wrinkles, melt fracture, etc. even when heated to the same temperature as conventional soft PVC when the laminated sheet is passed through an embossing apparatus. . Therefore, when the embossing pattern is transferred by the embossing apparatus, it is preferable that the elastic modulus does not significantly decrease at a heating temperature of about 160 ° C. to 190 ° C., which is a temperature at which the sheet is heated by the heater without a support. On the other hand, when laminating to a metal plate, it is desirable to obtain strong adhesion at the same heating temperature of the metal plate as in the case of the conventional soft PVC sheet, and from that point, it was heated to about 235 ° C. It is preferable that a high elastic modulus is not maintained in the state, and therefore it is preferable that the crystalline polyester resin not have a melting point exceeding 235 ° C.

  The lower limit of the melting point is set to 215 ° C because the temperature at which the sheet is heated by a heater without a support when the embossed design is transferred to a conventional soft PVC sheet by an embossing device is about 160 ° C to 190 ° C. On the other hand, when a PBT resin and / or PTT resin having a melting point of less than 215 ° C. is used as the resin component of the C layer (30), it becomes difficult to obtain sufficient tension at a heating temperature of 160 to 190 ° C., This is because it may be difficult to suppress width shrinkage, wrinkling, and melt fracture of the heated laminated sheet. In addition, the upper limit of the melting point is set to 235 ° C., when a PBT resin and / or a PTT resin having a higher melting point is used as a main component of the C layer (30), a sheet made of conventional soft PVC is used. This is because it is difficult to obtain a strong adhesion with the metal plate under the same temperature conditions as when laminating the metal plate.

  The reason why the main component of the C layer (30) is a PBT resin and / or a PTT resin is that these resins are not only in the above preferable melting point range, but also because the crystallization speed is relatively fast. This is because it is easy to obtain a C layer having high crystallinity in the film forming process without requiring a special curing process or the like between the film forming process and the embossing process. That is, this is because it becomes easy to obtain width-reducing, wrinkling and melt-breaking prevention properties and non-adhesiveness to the heated metal of the laminated sheet in the embossing step.

  Also in the polyethylene terephthalate (PET) resin, it is possible to obtain a resin having a melting point within the above range by substituting a part of terephthalic acid which is a dicarboxylic acid component with isophthalic acid. However, in this case, the crystallization speed is slow, and it is difficult to obtain a sufficiently crystallized C layer (30) with a normal extrusion film forming line, and a curing process is required. It is not preferable.

  Another reason for using the PBT resin and / or the PTT resin is that, for example, better processability can be obtained even in a crystallized state compared to the PET resin. In particular, regarding PBT-based resins, the development of applications such as extrusion film-forming grades has become active in recent years, and it is also easy to obtain PBT resin raw materials having various melt viscosities and melting points.

  The content ratio of the PBT resin and / or the PTT resin in the resin component of the C layer (30) is based on the mass of the entire resin component in the C layer (30) (100% by mass). And / or the ratio of the PTT resin (the ratio of the total when the PBT resin and the PTT resin are used together) is preferably 70% by mass or more, and more preferably 80% by mass or more. . When the content ratio is less than 70% by mass, it may be difficult to obtain a preferable melt tension even if the sheet is obtained in a state where the C layer is crystallized.

Moreover, it is important that the content ratio of the PBT resin and / or the PTT resin is 100% by mass or less based on the mass of the entire resin component in the C layer (30) (100% by mass). More preferably, it is 95 mass% or less, and it is especially preferable that it is 90 mass% or less.
Here, even if the content ratio exceeds 95% by mass, there is no practical problem. However, since the crystallinity of the C layer (30), which is the adhesive surface side when laminating the laminated sheet to the metal plate, becomes lower by setting it to 95% by mass or less, It is possible to further improve the adhesion strength. Even when the C layer is formed by a two-layer coextrusion film forming method with the B layer (20) or the three layer co-extrusion film forming method of the B layer, the D layer (40) and the C layer described later, It is possible to suppress the occurrence of warping of the laminated sheet after film formation, and it becomes easy to produce a laminated sheet excellent in secondary workability.

  The PBT resin having a melting point in the range of 215 ° C. or higher and 235 ° C. or lower was obtained by polycondensing each single component of terephthalic acid as the dicarboxylic acid component and 1,4-butanediol as the diol component ( A homopolybutylene terephthalate resin may be used in which an unintended copolymer component may be contained. Examples of the commercially available PBT resin having such a composition include trade name “Novaduran 5020H” manufactured by Mitsubishi Engineering Plastics Co., Ltd.

  In addition, homopolytrimethylene terephthalate resin can be used as the PTT resin having a melting point in the range of 215 ° C. or more and 235 ° C. or less. Examples of commercially available PTT resins having such a composition include Asahi Kasei Chemicals Corporation. The product name “Biomax PTT1002” can be given.

As the resin component other than the PBT resin and the PTT resin contained in the C layer (30), an amorphous polyester resin that is amorphous or low crystalline is preferably used. The same material as the main component of the layer (40) can be used. Since these resins are not highly crystalline aromatic polyester resins such as homo-PET resins, the crystal phase of the resin, which is inferior to the crystal phase of the PBT resin, has an adverse effect on the processability of the C layer (30). There is no risk. Therefore, the situation where the workability of the laminated sheet and the metal plate covered with the laminated sheet is lowered can be suppressed by using an amorphous polyester resin having an amorphous or low crystalline property.
However, it does not preclude containing other resins other than the amorphous polyester resin that is amorphous or low crystalline to the extent that the effects of the present invention are not significantly impaired.

  The thickness of the C layer (30) is preferably 20 μm or more, more preferably 25 μm or more, and further preferably 30 μm or more. When the thickness is equal to or greater than the above lower limit value, the C layer can satisfactorily exhibit the function of applying tension to the laminated sheet during embossing. In the case where only the C layer (30) is used as the additive layer of the color pigment, the thickness of the C layer is particularly preferably 40 μm or more from the viewpoint of satisfactorily exerting the shielding effect by the pigment. Further, the thickness of the C layer is preferably 200 μm or less, and more preferably 100 μm or less. When the thickness of the C layer is equal to or less than the above upper limit value, it is possible to maintain the secondary workability of the laminated sheet-covered metal plate without the total thickness of the laminated sheet of the present invention becoming too thick.

In the laminated sheet of the present invention, as described above, it is preferable that at least one of the B layer (20) and the C layer (30) contains a white pigment. In the case where a D layer (40) described later is provided between the B layer and the C layer, the B layer and the C layer can be configured so as not to contain a white pigment. In the case where the visual concealment effect of the base is insufficient by using only the layer, the C layer may further include a pigment.
As the white pigment, various known pigments can be used without particular limitation, but in particular, from the viewpoint of improving the concealability, it is preferable that the main component is a titanium oxide pigment. The content of the titanium oxide pigment in the white pigment is 50% by mass or more, preferably 70% by mass or more, more preferably 90% by mass or more, and may be 100% by mass.
When the white pigment is contained in the C layer (30), the color can be further adjusted by adding various inorganic and / or organic chromatic pigments.
As content when a white pigment is included in C layer (30), it is preferable to contain in the range of 20 mass parts-60 mass parts with respect to 100 mass parts of total resin which comprises C layer. More preferably, they are 25 mass parts-55 mass parts, More preferably, they are 30 mass parts-50 mass parts. By including a white pigment in such a content range, the laminated sheet-covered metal plate of the present invention is suitable for use as a white board or a screen board without impairing the formability of the laminated sheet of the present invention. It can be concealed.

  Moreover, in order to make the non-adhesiveness with a heating metal which is one of the purposes in which the C layer (30) is disposed more firmly, an appropriate amount of lubricant may be contained. As the lubricant, a known lubricant that may be added to the polyester resin can be used without particular limitation. As an example, a trade name “LICOWAX OP” (manufactured by Clariant Japan), which is a montanic acid-based lubricant, can be mentioned. The content of the lubricant can be 0.2% by mass to 3% by mass based on the total resin amount of the C layer (30) (100% by mass).

  In addition, in order to make the tension of the laminated sheet stronger during embossing, the layer C (30) has a linear ultrahigh molecular weight acrylic resin (for example, “Madebrene P- 531 "and the like, and processing aids such as polytetrafluoroethylene that has been subjected to an easy dispersion process that expands into a fibril form (for example, trade name" METABRENE A-3000 "manufactured by Mitsubishi Rayon Co., Ltd.) May be included). These contents can also be 0.2 mass%-3 mass% similarly to the above.

  Furthermore, in order to sufficiently impart the crystallinity necessary for obtaining non-adhesiveness and melt fracture resistance during embossing to the C layer (30) during film formation on an extrusion film forming line, it is known. These various crystal nucleating agents may be added to improve the crystallization rate. In addition, various additives that are generally known to be added to thermoplastic resins may be added in appropriate amounts as necessary.

<D layer (40)>
The laminated sheet of the present invention is a sheet having an A layer (10), a B layer (20), and a C layer (30), and is further amorphous or low crystalline between the B layer and the C layer. It is possible to have a D layer (40) containing 60% by mass or more of the entire resin component constituting the layer and containing a white pigment.
The thickness of the D layer is preferably 40 μm or more, and particularly preferably 50 μm or more, from the viewpoint of imparting a good color and concealing property to the laminated sheet of the present invention. The thickness of the D layer is preferably 120 μm or less, and particularly preferably 105 μm or less. By making the thickness of the D layer not more than the above upper limit value, it becomes possible to reduce the thickness while improving the secondary workability such as the bending process of the laminated sheet-coated metal sheet.

  The functions required for the D layer (40) are to make it possible to easily color the laminated sheet with the colored pigment and to impart good concealability to the laminated sheet with the colored pigment. In addition, in the configuration having the D layer, as described later, three layers of the B layer (20), the D layer (40), and the C layer (30) are laminated and integrated by a co-extrusion film forming method. It is desirable to produce sheets more efficiently.

(Amorphous or low crystalline aromatic polyester resin)
From the viewpoint of the functions required for the D layer, the D layer (40) is made of an amorphous or low-crystalline aromatic polyester resin, based on the mass of the entire resin component of the D layer (100% by mass). 60 mass% or more, preferably 70 mass% or more, more preferably 75 mass% or more.

  As described above, as for the amorphous or low crystalline aromatic polyester resin, in the differential scanning calorimetry (DSC), is a crystal melting peak observed when the temperature is increased at a temperature increase rate of 10 ° C./min? Alternatively, although a crystal melting peak is observed, an aromatic polyester resin having a heat of crystal melting (ΔHm) corresponding to the crystal melting peak of 10 J / g or less can be used.

The amorphous or low crystalline aromatic polyester-based resin is not particularly limited as long as it satisfies the above-mentioned crystal melting peak and crystal melting heat quantity, and can be appropriately selected. However, from the viewpoint of easy availability of raw materials, the dicarboxylic acid component is terephthalic acid, and the diol component is 1 to 20 mol% to 40 mol% based on the total amount of the diol component (100 mol%). , 4-cyclohexanedimethanol (1,4-CHDM) and a copolymerized polyester resin containing 60 mol% or more and 80 mol% or less of ethylene glycol are preferable.
When the diol component has the above composition, the progress of crystallization during heating in the embossing apparatus can be suppressed, and thus embossing can be particularly suitably performed on the laminated sheet of the present invention.

  At this time, the total amount of 1,4-CHDM and ethylene glycol is preferably 80 mol% or more, more preferably 90 mol% or more, based on the total amount of the diol component (100 mol%). It is particularly preferably 94 mol% or more.

  Among the copolyester resins in the above composition range, when the composition of 1,4-CHDM is around 30 mol% of the diol component, no crystallization behavior is observed even in DSC (Differential Scanning Calorimetry). It is known to show sex. An example of such a completely amorphous polyester resin is PETG resin. As a PETG resin, the brand name "Easter PETG 6763" by Eastman Chemical Co., etc. can be mentioned, for example. Since PETG resin is used for many applications, a stable supply system for raw materials has been established, and since cost reduction has been achieved, it is preferably used as the main component of the D layer (40). it can.

  However, the amorphous or low-crystalline aromatic polyester resin that can be used for the D layer (40) is not limited thereto. For example, the product name “PCTG 5445” of Eastman Chemical Co., which shows crystallinity under specific conditions but can be handled as an amorphous resin under normal extrusion film forming conditions and embossing conditions (dicarboxylic acid component is terephthalate). It is also possible to use a copolyester resin in which about 60 mol% of the diol component is 1,4-CHDM and about 40 mol% is ethylene glycol. In addition, neopentyl glycol copolymerized PET resin that does not exhibit crystallinity (for example, product name “COSMOSTER SI-173” manufactured by Toyobo Co., Ltd.), low crystallinity, and isophthalic acid are copolymerized. Copolymerized polyester resins having a structure in which crystallization is inhibited by introduction of various copolymerization components, such as PET resins and PBT resins having low crystallinity, can also be used as the main component of the D layer. However, from the viewpoint of facilitating coloring, which is the purpose of disposing the D layer, the pigment master batch using the PETG resin as a base resin is the most abundantly available. preferable.

As the white pigment contained in the D layer (40), various known pigments can be used. In particular, from the viewpoint of improving the concealability, it is preferable that the main component is a titanium oxide pigment. The content of the titanium oxide pigment in the white pigment contained in the D layer is 50% by mass or more, preferably 70% by mass or more, more preferably 90% by mass or more, and may be 100% by mass.
When the white layer is included in the D layer (40), the color can be further adjusted by adding various inorganic and / or organic chromatic pigments.
As a content in case a white pigment is included in D layer (40), it is preferable to contain in the range of 20 mass parts-60 mass parts with respect to 100 mass parts of total resin amount which comprises D layer. More preferably, they are 25 mass parts-55 mass parts, More preferably, they are 30 mass parts-50 mass parts. By including the white pigment in such a content range, without sacrificing the formability of the laminated sheet of the present invention, the laminated sheet-coated metal plate of the present invention is at a level suitable for use as a whiteboard or screen board, It becomes possible to have white concealment.

<Method for producing laminated sheet>
As a method for producing the laminated sheet of the present invention, various known methods such as a cast film forming method or an inflation method using an extruder equipped with a T die can be employed.

  In order to produce the laminated sheet of the present invention, two layers of “B layer (20) + C layer (30)” or “B layer (20) + D layer” having similar temperature setting ranges during extrusion film formation. The method of laminating and integrating the three layers (40) + C layer (30) ”by the co-extrusion film forming method using two or three extruders and a multi-manifold die is the most efficient and preferable. After that, the method of adhering and laminating the A layer obtained by the method described in the section of the A layer above and temporarily adhered to the carrier sheet on the B layer side surface by the dry laminating method has a restriction on equipment. It is difficult to receive and is preferable from the viewpoint of production efficiency.

  In the present invention, between the B layer (20) and the C layer (30), or between the B layer (20) and the D layer (40), and between the D layer (40) and the C layer (30), Since it is comprised by the composition which has heat-fusibility, after forming each layer independently, it is also possible to carry out lamination | stacking integration in the post process, and to make a lamination sheet. However, since the C layer (30) is formed in a state where crystallization has progressed, it can be heated between 160 ° C. and 190 ° C. in an embossing apparatus, or between the B layer (20) and the D layer. There is a possibility that it is not easy to obtain a good interlayer adhesion between (40) and (40). Also from this point, it is preferable that at least the layer between the B layer (20) and the C layer (30) or between the D layer (40) and the C layer (30) is laminated in the die by a coextrusion film forming method.

  The total thickness of the laminated sheets (100A, 100B) of the present invention is usually preferably in the range of 55 μm to 300 μm, and more preferably in the range of 80 μm to 200 μm. When the thickness of the laminated sheet is equal to or greater than the above lower limit value, the visual concealment of the base is ensured, and it is not necessary to add a large amount of pigment to the colored layer, thereby suppressing deterioration in workability due to the addition of the pigment. Is possible. On the other hand, when the thickness of the laminated sheet is less than or equal to the above upper limit value, problems such as occurrence of cracking in the resin layer in the bent portion are unlikely to occur, and the secondary workability is good. Therefore, it is possible to use a molding die that has been conventionally used for molding such as bending of a soft PVC resin-coated metal plate.

<Applying embossed irregularities>
The laminated sheet produced by the above method can be made into a laminated sheet suitable for a screen board by imparting a concavo-convex shape to the surface of the A layer (10) with an embossed plate. The laminated sheet of the present invention gives an emboss to the surface of the A layer side in the same manner as the conventional soft PVC resin sheet by various embossing apparatuses generally used to give an emboss pattern to the soft PVC resin sheet. be able to.

  In FIG. 2, an example of the embossing apparatus (400) generally used in order to provide an embossed pattern to a flexible PVC sheet is shown. The illustrated embossing device (400) includes a heating roll (410), a take-off roll (420), an infrared heater (430), an embossing roll (440), a nip roll (450), and a cooling roll (460). In this embossing apparatus (400), a roll-like embossing roll (450) is used as an embossing plate. However, the shape of the embossed plate is not particularly limited as long as it is a plate on which an embossed design is formed, and may be a plate shape, a roll shape, or a belt shape. Normally, a metal roll whose surface is embossed and engraved is used.

  The laminated sheet of the present invention has non-adhesiveness to the heated roll (410) heated to about 100 ° C. to 140 ° C. by having the C layer (30). Further, even at 160 ° C. to 190 ° C., which is the sheet heating temperature by the infrared heater (430), the width reduction, wrinkling, breakage, and the like of the laminated sheet are suppressed. Moreover, by having B layer (20), the laminated sheet for screen boards to which the favorable mat | matte embossing was provided can be obtained. In particular, it is preferable to appropriately adjust the temperature of the embossing roll (450) to a temperature slightly below the glass transition temperature of the resin composition of the B layer (20). By adjusting the temperature, when the laminated sheet comes into contact with the embossing roll (450), the embossing is fixed by cooling as well as embossing. Easy to get.

<Laminated sheet coated metal plate>
As shown schematically in FIG. 1 (e) and FIG. 1 (f), the laminated sheet-covered metal plate of the present invention has the C layer (30) side surface in the laminated sheet of the present invention as an adhesive surface. If necessary, it is laminated on the metal plate (70) through an adhesive (60).

  As the metal plate (70) used for the laminated sheet-coated metal plate of the present invention, hot rolled steel plate, cold rolled steel plate, hot dip galvanized steel plate, electrogalvanized steel plate, tin plated steel plate, aluminum / zinc alloy plated steel plate, aluminum / magnesium -Various steel plates such as zinc alloy plated steel plates, stainless steel plates, aluminum plates, aluminum alloy plates, titanium alloy plates, magnesium alloy plates, etc. can be used, and these can be used after the usual chemical conversion treatment. Good. The thickness of the metal plate (70) can be selected in the range of 0.1 mm to 10 mm. Among these, when a steel plate-based metal plate is used, the laminated sheet-covered metal plate of the present invention has a function as a reflective screen, a function as a white board, and a function as a magnet board. You can have it.

The method for laminating the laminated sheet of the present invention on the metal plate (70) is not particularly limited, but it is an existing method to laminate the conventional soft PVC resin sheet on the metal plate (70). It is preferable from the viewpoint that facilities can be used.
That is, a laminate using an adhesive (60) is preferably used, and examples of the adhesive that can be used as the adhesive (60) include acrylic adhesives, epoxy adhesives, urethane adhesives, polyester adhesives, and the like. The generally used thermosetting adhesive can be mentioned. Among these, it is preferable to use a polyester-based adhesive because the C layer (30) of the laminated sheet has an aromatic polyester-based resin as a main component.

  As a method for producing the laminated sheet-coated metal plate of the present invention, for example, a metal plate (70) is used on a metal surface on which a laminated sheet is bonded by using commonly used coating equipment such as a reverse coater and a kiss coater. Then, after applying a thermosetting adhesive so that the thickness of the adhesive film after drying is about 1 μm or more and about 10 μm or less, the coated surface is dried and heated by an infrared heater and / or a hot air heating furnace to form a metal plate (70 ) Is maintained and maintained at a temperature of about 230 ° C. or more and 250 ° C. or less, and a roll laminator is used to immediately coat and cool the laminated sheet so that the C layer (30) side of the laminated sheet becomes an adhesive surface. .

  According to the laminated sheet-coated metal plate of the present invention, (1) the characteristics as a reflective screen and the characteristics as a whiteboard are both good, and (2) yellowing due to aged light deterioration is achieved. In addition, it is possible to suppress the occurrence of cracks and cracks in the bending process, and (3) it is possible to obtain a laminated sheet-covered metal plate that can be easily subjected to secondary processing such as panel processing.

  In addition, according to the screen board, the white board, the reflective screen, and the building interior material having the laminated sheet-coated metal plate of the present invention, (1) both the characteristics as the reflective screen and the characteristics as the white board are provided. In addition to being good, (2) yellowing caused by age-related light deterioration can be suppressed. (3) Only when installed inside buildings where there are many windows, such as offices and conference rooms. Even when it is completely built, it can be used as a screen board, a white board, a reflective screen, and a building interior material that can be used for a long time.

  In order to describe the present invention more specifically and in detail, examples are shown below. In addition, this invention is not limited at all by the following Example.

(Examples 1-4, Comparative Examples 1-4)
<Manufacture of laminated sheets>
In obtaining the A layer, a single-screw extruder having a vent device at one location with a cylinder diameter of φ65 mm and subjected to corrosion prevention treatment for fluororesin extrusion was used. A-layer ethylene-tetrafluoroethylene copolymer resin (Asahi Glass Co., Ltd., “Fluon ETFE” C-88AXP) was allowed to flow down from a T die set at 315 ° C. and unwound from the unwinding shaft in the manner of extrusion lamination. The thin film fluororesin layer and the biaxially stretched polyester are brought into contact with the corona-treated surface side of the biaxially stretched polyester film (Teijin DuPont Films, “Tetron S”, thickness 25 μm) on the casting roll (take-off roll). It was set as the laminated sheet of the state which adhered to the film temporarily. The laminated sheet was wound and collected as it was. In addition, the contact pipes and the T die are also subjected to corrosion prevention treatment for extruding the fluororesin. The thickness of the A layer is adjusted by adjusting the take-up speed. Table 1 shows the thicknesses of the A layers of Examples 1 to 4 and Comparative Examples 1 to 4.

On the other hand, the B layer and the C layer are obtained by co-extrusion film formation using a multi-manifold die using two co-directional twin-screw kneading extruders each having a vent device at two locations with a cylinder diameter of φ65 mm. A coextruded laminated sheet consisting of two layers of a B layer and a C layer was obtained by a method in which the resin flown out of the die was drawn with a casting roll (take-off roll). The cylinder set temperature of the extruder is 210 ° C. on the feed side and 240 ° C. on the base side, and the same applies to each extruder. The set temperature of the T die was 240 ° 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 was 250 ° C.
As the resin component of the B layer, a polycarbonate resin (isosorbide: 1,4-cyclohexanedi) obtained by melt polymerization using isosorbide as a dihydroxy compound and 1,4-cyclohexanedimethanol which is an alicyclic dihydroxy compound. Methanol = 70 mol%: 30 mol%) pellets were used. The glass transition temperature of the resin component measured by differential scanning calorimetry was about 130 ° C. Differential scanning calorimetry was performed using “Pyris 1” manufactured by PerkinElmer. As the colorant, a pigment having a titanium oxide pigment as a main component and a color adjusted to beige by adding an organic pigment was used. Using the polycarbonate resin as a base resin, a pigment master batch pellet having a concentration of 50% by mass was obtained by a same-direction biaxial kneader / extruder having a vent device at one location with a cylinder diameter of 35 mm equipped with a strand die. The pigment master batch pellet is mixed with the polycarbonate resin so that the pigment component amount is 30 parts by mass with respect to 100 parts by mass of the total resin composition of the B layer, and the composition of the B layer (composition b-1) ) B layer was produced by extruding the composition from the T-die to form a film. The set temperature of the kneading extruder at the time of preparing the master batch is 210 ° C. on the feed side and 240 ° C. on the base side, and the set temperature of the strand die is also 240 ° C.
In Examples 1 to 4 and Comparative Examples 1, 2, and 4, all the B layers use the composition b-1 and all have a thickness of 60 μm. The comparative example 3 is a structure which does not have a B layer, and only the C layer is extruded and formed as a single layer, and then laminated and integrated with the A layer by a dry laminate bonding method.

The resin composition of the C layer was obtained as follows. (Homo) polybutylene terephthalate resin (Mitsubishi Engineering Plastics, “Novaduran 5020S”) having a melting point of 224 ° C. is 80% by mass, based on the total amount of the resin component of the C layer (100% by mass), and is amorphous. Each resin pellet is mixed so that the conductive polyester resin (Easterman Chemical Company, “Easter PETG 6763”) is 20% by mass, and the resin composition of the C layer (composition c-1) Got. C layer was produced by extruding the composition from the T-die to form a film. In addition, the coloring pigment is not added in the composition c-1.
“Easter PETG 6763” has a dicarboxylic acid component of terephthalic acid, a diol component of about 30 mol% of 1,4-cyclohexanedimethanol, about 70 mol% of ethylene glycol, and several mol% of diethylene glycol. Including. The melting point was not observed by differential scanning calorimetry, and the glass transition temperature measured by differential scanning calorimetry was about 78 ° C. In Examples 1 to 4 and Comparative Examples 1 to 3, all the C layers use the composition c-1, and the thicknesses are all 20 μm. Comparative Example 4 has a configuration having no C layer, and only the B layer is extruded and formed as a single layer, and then laminated and integrated with the A layer by a dry laminate bonding method.

The above-obtained temporary adhesion laminated sheet of the A layer and the biaxially stretched polyester film and the two-layer coextruded laminated sheet of the B layer and the C layer are adhesively laminated by a dry lamination adhesion method, and the A layer , B layer, and C layer.
Dry lamination was performed as follows. 5 parts by mass of an isocyanate curing agent (Mitsui Takeda Chemical Co., Ltd., “Takenate A3”) is mixed with 100 parts by mass of the solid content of the main component of the polyester adhesive (Toyo Morton, “TM-K51”). An organic solvent-based adhesive was obtained. The adhesive was applied to the surface of the B layer side of the laminated sheet composed of the B layer and the C layer by a gravure coater so that the dry film thickness was about 1 μm. The laminated sheet coated with the adhesive was continuously introduced into a hot air drying furnace set at about 80 ° C. to volatilize the solvent component in the adhesive. Subsequently, between the pair of pressure rolls, a sheet A composed of two layers of a B-layer side surface of the laminated sheet coated with the adhesive and a biaxially stretched polyester film temporarily adhered to the A layer and the A layer. By laminating and pressing the layer side surface, lamination was integrated. The obtained laminated sheet was left in a curing room at about 40 ° C. for 24 hours to complete dry lamination.
In addition, since it has the structure which does not have A layer regarding the comparative example 2, the adhesive lamination by the dry lamination method is not implemented.

<Embossing to laminated sheet>
The embossing was transferred by embossing using an embossing apparatus (400) generally used for embossing a soft vinyl chloride sheet as shown in FIG. As a process outline of the embossing apparatus, first, the sheet is preheated by contact-type heating using a heating roll (410). Subsequently, the sheet is heated to an arbitrary temperature by non-contact type heating using an infrared heater (430), and the embossed roll (450) transfers the unevenness due to the embossing to the surface of the A layer side to obtain an embossed sheet. is there.

  The process which provided the unevenness | corrugation by embossing to the sheet | seat of a present Example and a comparative example is demonstrated. The heating roll (410) was set to 110 ° C., and then heated with an infrared heater (430) so that the sheet surface temperature immediately before contacting the embossing roll (440) was 180 ° C. The embossing roll (440) is adjusted to 110 ° C. by a hot water circulator. The embossing roll used is sculpted to give a matte appearance called a satin finish with Rmax (maximum height) = 19 μm and RzJIS (10-point average roughness) = 16 μm as specified in JIS B0601. ing.

<Production of laminated sheet-coated metal plate>
Surface of metal plate (galvanized steel plate, thickness 0.45 mm) on which a laminated sheet is bonded with a commercially available polyester adhesive for polyvinyl chloride coated metal plate (product name “Byron 20SS” manufactured by Toyobo Co., Ltd.) The coated surface was dried by passing through an oven set at a temperature of 80 ° C. in 30 seconds, and the thickness of the adhesive film after drying was about 2 to 4 μm. Next, the coated surface is heated by passing through a hot air drying oven set at 350 ° C. in 30 seconds to raise and hold the surface temperature of the metal plate to 235 ° C. Using a controlled roll laminator, cover the laminated sheet in such a positional relationship that the C layer side surface of the laminated sheet faces the adhesive application surface of the metal plate with a clamping pressure of 50 N / cm between the rolls, and then cool to room temperature Thus, a laminated sheet-coated metal plate was obtained.

(Examples 5-9, Comparative Examples 5-7)
It is evaluation at the time of changing about the resin composition of B layer, and thickness.
The resin composition and production method for the A layer are the same as those in Examples 1 to 4 and Comparative Examples 1, 3, and 4, and the conditions for adhesive lamination by the dry lamination method with the B layer are also the same. The thickness is the same at 4 μm in Examples 5 to 9 and Comparative Examples 5 to 7. Moreover, the resin composition of C layer is also the same as Examples 1-4 and Comparative Examples 1-3, and it is the same also about the point which carries out lamination | stacking integration by B layer and coextrusion film forming. The thickness of the C layer is the same at 20 μm in Examples 5 to 9 and Comparative Examples 5 to 7.

Composition b-2 used in Example 9 uses isosorbide as a dihydroxy compound and 1,4-cyclohexanedimethanol, which is an alicyclic dihydroxy compound, at a copolymerization ratio of 50 mol%: 50 mol%. Using the polycarbonate resin pellets obtained by the melt polymerization method, the same amount of the color pigment as the resin composition b-1 was used in the same manner as described above, and the amount of the pigment component was 100 parts by mass with respect to the total amount of the resin component of the B layer. It is a composition mixed so that it may become 30 mass parts. The glass transition temperature of the resin component measured by differential scanning calorimetry was about 105 ° C.
Composition b-3 used in Comparative Example 6 uses pellets of aromatic polycarbonate resin (manufactured by Mitsubishi Engineering Plastics Co., Ltd., “Novalex 7025A”) as a resin component, and has the same color as composition b-1 The same amount of pigment is added. However, the optimum melt molding temperature of the resin component is relatively high, the set temperature of the kneading extruder when preparing the pigment master batch is 240 ° C. on the feed side, 280 ° C. on the base side, and the set temperature of the strand die is also 280. ℃. In addition, also in the production of a laminated sheet by co-extrusion with the C layer, the extruder on the side where the composition b-3 is charged raises the set temperature, and the temperature settings of the connecting conduit and the T die are also raised to 280 ° C. .
Composition b-4 used in Comparative Example 7 uses an amorphous polyester resin (manufactured by Eastman Chemical Co., “PETG 6763”). The pigment masterbatch which made the base resin the commercially available PETG which is a color similar to Examples 5-9 was purchased, and this is 30 mass parts of pigment component amounts with respect to 100 mass parts of resin composition whole quantity of B layer. It is the composition mixed so that. The temperature conditions for extrusion film formation are the same as in Examples 1 to 4. The configuration can also be considered as a configuration having a D layer without a B layer.
The embossing unevenness transfer conditions and the laminating conditions on the metal plate are the same. It showed in Table 2 regarding the composition of B layer of Examples 5-9 and Comparative Examples 5-7, and the thickness of B layer.

(Example 10, comparative example 8)
It is evaluation regarding the structure containing D layer. The composition d-1 used for the D layer is the same as the composition b-4 used for the B layer in Comparative Example 7 described above. In Example 10 and Comparative Example 8, the composition and thickness of the D layer are the same, and the thickness of the B layer is changed. In addition, with the use of the D layer as the colored layer, the composition “b-5” is used for the B layer. The resin component of the composition b-5 is the same as that of the composition b-1, but the composition b-5 does not contain a color pigment. Instead, a benzotriazole type ultraviolet absorber (“LA-31” manufactured by Adeka Corporation) is used. 3 parts by mass with respect to 100 parts by mass of the entire resin component b-5.
A three-layer coextrusion laminated sheet of B layer, D layer and C layer was produced as follows. For extruding the resin composition of the B layer and the C layer, using two same-direction biaxial kneading extruders having a vent device at two locations with a cylinder diameter of φ65 mm, respectively, for extruding the resin composition of the D layer The resin flowing out from the T-die was formed by the co-extrusion film-forming method using a multi-manifold tie with a total of three extruders using a co-directional twin-screw kneading extruder having a vent device at two locations with a cylinder diameter of φ37 mm. A three-layer co-extruded laminated sheet was obtained by a method of drawing with a casting roll (take-up roll). The cylinder set temperature of the extruder is 210 ° C. on the feed side and 240 ° C. on the base side, and the same applies to each extruder. The set temperature of the T die was 240 ° 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 was 250 ° C.

  The layer A of Example 10 and Comparative Example 8 uses the same composition and thickness as in Example 2. The method for forming the layer A and the dry lamination adhesion to the layer B side surface of the laminated sheet These conditions are also the same as in the second embodiment. Moreover, the embossing unevenness transfer conditions by the embossing apparatus, the lamination conditions to the metal plate, and the like are the same. The thickness of each layer of Example 10 and Comparative Example 8 is shown in Table 3.

<Evaluation of laminated sheet and laminated sheet-coated metal plate>
The following items were evaluated for the laminated sheets and laminated sheet-covered metal plates obtained in the above Examples and Comparative Examples. The results are summarized in Table 4, Table 5, and Table 6.

(1) Embossing suitability: Embossing transferability With the embossing device (400) shown in Fig. 2, the surface of the layer A side of the laminated sheet to which the embossing design has been applied is visually observed, and the embossed unevenness is clearly transferred. `` ◎ '', when the transfer is slightly shallower and unclear compared to this, but when there is no problem in practical use `` ○ '', the transfer is poor and the embossed design is shallow, or the surface is simply rough regardless of the embossed design Are indicated by "x". In addition, although troubles such as adhesion and breakage occurred in the embossing apparatus and the emboss transfer was difficult, it was indicated as “x”, but in this case, the subsequent evaluation was not performed.

(2) Embossing heat resistance The embossing unevenness given to the layer A side surface of the laminated sheet before laminating on a metal plate was measured with a surface roughness meter ("Surfcoder" SE-40D manufactured by Kosaka Laboratory), The roughness was measured again after laminating the laminated sheet on the metal plate, and the residual height of the emboss was determined with Ry1 (μm) as the maximum height before lamination and Ry2 (μm) after lamination (residual). Rate: Ry2 / Ry1 × 100 (%)).
The case where the residual rate is 80% or more is “、”, the residual rate is less than 80%, but the case where it is not visually recognized as a remarkable abnormality is “◯”, the residual rate is less than 80%, The case where the design feeling of embossing is clearly lowered visually is indicated by “x”. As described above, the embossing heat resistance of the embossing apparatus in which troubles such as adhesion and breakage occurred has not been evaluated.

(3) Measurement of surface gloss value (60-degree specular gloss) A layer of laminated sheet-coated metal sheet in accordance with JIS K7105 using a portable gloss meter ("Handy Gloss Meter / CG1382") manufactured by Suga Test Instruments Co., Ltd. The 60-degree specular gloss of the side surface was measured. The average value was measured in n = 5 and listed in Tables 4, 5, and 6.

(4) Presence / absence of “shining ball” With a liquid crystal projector (“ELP-3500”, manufactured by Epson Corporation), images and characters are projected on the surface of the layer A side of the laminated sheet-coated metal plate from a distance of about 2 m. The presence or absence of “balls” and the degree of deterioration in the visibility of images and video accompanying the occurrence of “balls” were evaluated visually. “◎” when no “light ball” is generated and the visibility of the projected image is very good, and “light ball” is slightly generated but the level of the projected image is ensured A case where “◯” and a strong “shining ball” were generated and it was extremely difficult to visually recognize the projected image of the portion was designated as “X”.

(5) Writability With “PM-B102ND” whiteboard marker black made by KOKUYO Co., Ltd., write characters on the surface of the layer A side of the laminated sheet-coated metal plate, visually observe the character repelling and bleeding, and repelling and bleeding. The case where there was no writing and the writing property was judged to be good was indicated as “◯”, and the case where the writing property was poor due to repelling and bleeding was designated as “x”.

(6) Eraseability Characters written in the above-described evaluation of writing property were erased with a whiteboard eraser manufactured by KOKUYO, and the erased state was observed visually. Characters can be erased by wiping within 2 times with a marker eraser, and no black portion remains. “◯” indicates that black portions remain after wiping within 2 times.

(7) Pencil Hardness The surface of layer A of the laminated sheet-coated metal plate was subjected to JIS K5600 5.4 (1999) “Scratch hardness (pencil method)”. Drawing in a temperature-controlled room at 23 ° C. using a jig that can draw a load of 9.8 N while maintaining a 45 ° angle with respect to the resin sheet surface of the resin-coated metal plate cut out to 80 mm × 60 mm The surface condition was visually judged, and the hardness of the pencils that were not damaged by 5 trials was recorded in the table.

(8) Bending workability An impact adhesion bending test is performed on the laminated sheet-covered metal plate, and the sheet surface state of the bent portion is visually determined. “△” and those with cracks were displayed as “x”. The impact adhesion bending test was performed as follows. Samples of 50 mm × 150 mm are prepared from the length direction and the width direction of the coated metal plate, respectively, and kept at 23 ° C. for 1 hour or longer. Then, using a bending tester, the side coated with the laminated sheet is placed outside. The sample was bent at 180 ° (inner bending radius: 2 mm), and a cylindrical weight having a diameter of 75 mm and a mass of 5 kg was dropped on the sample from a height of 50 cm.

(9) Weather resistance A laminated sheet-coated metal plate was cut out to 60 mm × 50 mm and subjected to a test using a sunshine weather meter / weather resistance promotion tester (“S80” manufactured by Suga Test Instruments Co., Ltd.). The conditions were a black panel temperature of 63 ° C., a cycle of 102 minutes of irradiation and 120 minutes of spraying of 18 minutes, and for a sample after 500 hours of exposure, a color difference meter “CR- 200 "was used to measure the color difference. A sample having a color difference of 1.5 or less was evaluated as “◎”, a sample having a color difference of more than 1.5 but 3 or less was evaluated as “◯”, and a sample having a color difference exceeding 3 was determined as “X”.

  <Evaluation results>

<Summary of evaluation results of laminated sheet and laminated sheet-coated metal plate>
(Examples 1-4, Comparative Examples 1-4)
The comparative example 1 is a case where the layer which consists of ethylene-tetrafluoroethylene copolymer resin used as the outermost surface layer of a lamination sheet coating | coated metal plate is excessively thick. In Comparative Example 1, it is difficult to achieve good emboss transfer with an embossing apparatus. As a result, the 60 degree specular glossiness is high, and when the projector is irradiated, the visibility of the projected image deteriorates due to the occurrence of “shining balls”. Yes. Moreover, the pencil hardness is also deteriorated because the A layer is thick. Comparative Example 2 is a case where there is no A layer, and the characteristics of the resin component of the B layer in the present invention are that the emboss transferability and the emboss heat resistance are good, and the pencil hardness is also high, Erasability is insufficient for use on boards.
Comparative Example 3 is a case where the B layer does not exist, and troubles such as adhesion and breakage in the embossing apparatus did not occur, but emboss transfer itself was not completed. As a result, the 60-degree specular gloss is high, and the visibility when used as a reflective screen is poor. The weather resistance of Comparative Example 3 is poor because light yellowing is suppressed and there is no B layer to which a coloring pigment is added in such an amount that a sufficient visible light hiding property is obtained. This is because the ultraviolet rays that are generated cause yellowing of the C layer and that the yellowing is visually recognized from the surface of the A layer side. In Comparative Example 4, there was no C layer, and it was difficult to transfer the emboss due to adhesion to the heated metal roll of the embossing apparatus.

  On the other hand, in Examples 1 to 4 of the present invention, the embossing transfer property and the embossing heat resistance are good, and since “shining balls” are not generated, it has suitability as a reflective screen. In addition, it has the appropriateness as a whiteboard because it has excellent writing and erasability. Furthermore, since the weather resistance is good, it can be seen that there is no risk of light yellowing over time even when it is constructed as a built-in wall that is not easy to replace. In particular, in Examples 1 and 2 in which the thickness of the A layer is thin, pencil hardness and emboss transferability are further superior to those in Examples 3 and 4. It can be seen that the composition of the A layer is preferably used as thin as possible within the range in which film formation and adhesion lamination are not difficult, including the high cost of raw materials.

(Examples 5-9, Comparative Examples 5-7)
Comparative Example 5 is a case where the thickness of the B layer is thin and the D layer is not present, resulting in poor emboss transferability. Therefore, the gloss value at 60 ° C. was high, and the occurrence of “shining balls” was unsuitable for use as a reflective screen.
Comparative Example 6 uses an aromatic polycarbonate resin to which a color pigment is added as the composition of the B layer, but the composition b-1 used in the examples of the present invention is already used at the time of film formation. The film was slightly yellower than the film formed. The cause is presumed that the temperature at the time of preparing the pigment master batch and at the time of forming the sheet is high. The pigment type itself used is the same as that used in the composition b-1, but it seems that there was no heat resistance up to the film forming temperature of the aromatic polycarbonate resin. Although emboss transferability and heat resistance are good and there is no problem in use as a reflective screen or whiteboard, it has resulted in poor weather resistance, and it is used for a long time in the application of screen boards used as built-in walls There is a risk that yellowing will gradually progress. Comparative Example 7 is a case where a PETG resin added with a color pigment was used as the composition of the B layer, and the embossing transfer itself was good, but the embossing heat resistance was insufficient and embossing at the time of lamination to a metal plate As a result, the gloss value increases, and the characteristic as a reflective screen cannot be provided. Moreover, the temperature at the time of film formation may be lower than the comparative example 6, and although composition b-4 used for B layer did not exhibit thermal yellowing at the time of film formation, the result of a weather resistance evaluation was bad. Even in the case of aromatic polyester-based resins, there is a possibility that problems may occur in long-term use. Moreover, the visibility when used as a reflective screen is deteriorated due to the occurrence of “shining balls”.

On the other hand, in Examples 5 to 9, both the suitability as a reflection type screen and the suitability as a whiteboard are excellent, and the weather resistance is also good. In particular, Examples 6 to 8, in which the thickness of the B layer is thicker than Example 5, are further superior to Example 5 in terms of emboss transferability and suppression of “shining balls”.
Example 9 is a case where the composition b-2 having a slightly lower glass transition temperature is used as the composition of the B layer. In this case as well, there were no problems in suitability as a reflective screen, suitability as a whiteboard, and weather resistance.

(Example 10, comparative example 8)
Although the comparative example 8 is a structure which has D layer, it is a case where the thickness of B layer is too thin. In Comparative Example 8, there was no problem with the emboss transferability, but the emboss heat resistance was insufficient. As a result, when the laminated sheet-coated metal plate is used, the gloss value increases due to the embossing return, and it is not suitable as a reflective screen.

  In Example 10, the emboss transferability is good, and while the thickness of the B layer is thin, good performance can be imparted with respect to suitability as a reflective screen and suitability as a whiteboard. At the same time, there is an advantage that the layer D can be easily colored using a commercially available coloring master batch. Moreover, since all the examples except the comparative example 4 which was not able to be set as a laminated sheet covering metal plate, and the comparative example, since the galvanized steel plate is used as a metal plate, it is a paper document with a magnet. It can be confirmed that can be easily fixed and removed from the surface of the A layer side.

  From the results of the examples and comparative examples described above, according to the present invention, (1) the characteristics as a reflective screen and the characteristics as a whiteboard are both good, and (2) a general embossing apparatus (3) It is possible to suppress embossing return when laminating to a metal plate, (4) It is possible to suppress yellowing due to aged light degradation, and (5) It has been shown that it is possible to provide a laminated sheet capable of suppressing the occurrence of cracks and cracks in a bending process after being laminated on a metal plate. In addition, (1) the characteristics as a reflective screen and the characteristics as a whiteboard are both good, (2) it is possible to suppress yellowing due to aged light deterioration, and (3) It was shown that it is possible to provide a laminated sheet-covered metal plate that can be easily subjected to secondary processing such as panel processing because cracks and cracks can be suppressed in bending.

  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. However, the invention can be changed as appropriate without departing from the spirit or concept of the invention that can be read from the claims and the entire specification, and the laminated sheet, the laminated sheet-coated metal plate, the screen board, and the architecture with such a change. Interior materials and the like should also be understood as being included within the technical scope of the present invention.

10 A layer 20 B layer 30 C layer 40 D layer 50 Dry laminate adhesive layer
60 Metal plate laminating adhesive layer 70 Metal plate 100A, 100B Laminated sheet 200A, 200B Embossed transfer laminated sheet 300A, 300B Laminated sheet coated metal plate 410 Heating roll 420 Take-off roll 430 Infrared heater 440 Embossed roll 450 Nip roll 460 Cooling roll

Claims (15)

A laminated sheet having an A layer, a B layer, and a C layer,
The layer A is a layer containing 50% by mass or more of an ethylene-tetrafluoroethylene copolymer resin and having a thickness of 15 μm or less.
The layer B is a layer containing 50% by mass or more of a polycarbonate resin containing a structural unit derived from the dihydroxy compound represented by the formula (1) and having a thickness of 20 μm or more.
The C layer contains at least one selected from a polybutylene terephthalate resin having a melting point of 215 ° C. or more and 235 ° C. or less, and a polytrimethylene terephthalate resin having a melting point of 215 ° C. or more and 235 ° C. or less, The total amount of the butylene terephthalate resin and the polytrimethylene terephthalate resin is a layer that is 70% by mass or more and 100% by mass or less of the entire resin component constituting the C layer,
The laminated sheet, wherein the B layer is disposed between the A layer and the C layer.

  2. The laminated sheet according to claim 1, wherein the polycarbonate resin contained in the B layer has a glass transition temperature measured at a heating rate of 10 ° C./min by differential scanning calorimetry at 100 ° C. or more and 155 ° C. or less.   The laminated sheet according to claim 1 or 2, wherein an emboss is provided on the surface of the A layer.   The laminated sheet according to any one of claims 1 to 3, wherein at least one layer selected from the B layer and the C layer contains a white pigment.   The laminated sheet according to any one of claims 1 to 4, wherein the dihydroxy compound represented by the formula (1) is 1,4: 3,6-dianhydro-D-sorbitol. A D layer is disposed between the B layer and the C layer,
The D layer is a layer containing a non-crystalline or low-crystalline aromatic polyester resin in an amount of 60% by mass or more based on the entire resin component constituting the D layer, and a white pigment. The laminated sheet according to any one of claims 1 to 5. The aromatic polyester resin contained in the D layer is a polyester resin obtained by copolymerizing a terephthalic acid component and a diol component,
The diol component contains 20 mol% or more and 40 mol% or less 1,4-cyclohexanedimethanol and 60 mol% or more and 80 mol% or less ethylene glycol based on 100 mol% of the diol component as a whole. 6. The laminated sheet according to 6.   The laminated sheet according to any one of claims 1 to 5, wherein the B layer and the C layer are laminated and integrated by a coextrusion film forming method.   The laminated sheet according to claim 6 or 7, wherein the B layer, the D layer, and the C layer are laminated and integrated by a coextrusion film forming method.   The laminated sheet according to any one of claims 1 to 9, wherein the 60-degree specular gloss measured on the surface of the A layer side in accordance with JIS K7105 is 30% or less.   A laminated sheet-coated metal sheet, wherein the laminated sheet according to any one of claims 1 to 10 is laminated on a metal sheet with the surface on the C layer side as an adhesive surface.   A screen board comprising the laminated sheet-coated metal plate according to claim 11.   A whiteboard comprising the laminated sheet-coated metal plate according to claim 11.   A reflective screen comprising the laminated sheet-coated metal plate according to claim 11.   A building interior material comprising the laminated sheet-coated metal plate according to claim 11.

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