JP2018158549A - Thermally-expandable sheet and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermally-expandable sheet that can prevent a thermally expansion layer from peeling off from a base material when the thermally expansion layer is expanded, and a method for producing the thermally-expandable sheet.SOLUTION: A thermally-expandable sheet 10 has an anchor layer 12 on one face of a base material 11, and a thermally expansion layer 13 on the anchor layer 12. The anchor layer 12 has excellent adhesiveness to the base material 11 and the thermally expansion layer 13, so that it is possible to prevent the thermally expansion layer 13 from peeling off from the base material 11 when the thermally expansion layer 13 is heated and expanded.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a thermally expandable sheet that expands by expansion according to the amount of heat absorbed, and a method for producing the thermally expandable sheet.

  2. Description of the Related Art Conventionally, a thermally expandable sheet is known in which a thermally expandable layer including a thermally expandable material that expands and expands according to the amount of heat absorbed is formed on one surface of a base sheet. By forming a light-to-heat conversion layer that converts light into heat on the thermally expandable sheet and irradiating the light-to-heat conversion layer with light, the heat-expandable layer can be partially or wholly expanded. Moreover, the method of forming a three-dimensional molded item (stereoscopic image) on a thermally expansible sheet | seat by changing the shape of a photothermal conversion layer is also known (for example, refer patent document 1, 2).

JP-A 64-28660 JP 2001-150812 A

  However, in the thermally expandable sheet in which the thermal expansion layer is directly formed on the base material, the thermal expansion layer may peel from the base material when the thermal expansion layer is expanded by foaming. Further, peeling often occurs particularly when a resin sheet (film) is used as a substrate.

  Accordingly, there is a need for a thermally expandable sheet and a method for producing the thermally expandable sheet that can prevent the thermally expandable layer from peeling from the base material when the thermally expandable layer is expanded.

  The present invention has been made in view of the above circumstances, and a thermally expandable sheet and a thermally expandable sheet capable of suppressing the thermal expandable layer from peeling off from the base material when the thermally expandable layer is expanded. It aims at providing the manufacturing method of a sheet | seat.

In order to achieve the above object, the thermally expandable sheet according to the present invention is:
An anchor layer formed on one side of the substrate;
A thermal expansion layer formed on the anchor layer,
The substrate is a film made of resin,
The anchor layer includes at least one resin selected from the group consisting of polyester, acrylic, polyurethane, or any copolymer thereof.
It is characterized by that.

In order to achieve the above object, a method for producing a thermally expandable sheet according to the present invention includes:
Forming an anchor layer on one side of the substrate;
Forming a thermal expansion layer on the anchor layer, and
The substrate is a film made of resin,
In the step of forming the anchor layer,
On one surface of the base material, the anchor layer is made of at least one resin selected from the group consisting of polyester, acrylic, polyurethane, or any copolymer thereof, or the base material An anchor layer is formed by applying a corona treatment on one side of
It is characterized by that.

  According to the present invention, it is possible to provide a thermally expandable sheet and a method for producing the thermally expandable sheet that can prevent the thermally expandable layer from peeling from the base material when the thermally expandable layer is expanded. Can be provided.

It is sectional drawing which shows the outline | summary of the thermally expansible sheet which concerns on Embodiment 1. FIG. It is sectional drawing which shows the outline | summary of the manufacturing method of the thermally expansible sheet which concerns on Embodiment 1. FIG. It is a figure which shows the outline | summary of the corona treatment apparatus which concerns on Embodiment 1. FIG. 2 is a diagram illustrating an overview of a stereoscopic image forming unit according to Embodiment 1. FIG. 3 is a flowchart illustrating a stereoscopic image forming process according to the first embodiment. FIG. 3 is a cross-sectional view illustrating an overview of a stereoscopic image forming process according to the first embodiment. (A) It is a graph which shows the relationship between the black density of the photothermal conversion layer at the time of heating at a 1st level, and the convex amount of a thermal expansion layer. (B) It is a graph which shows the relationship between the black density of the photothermal conversion layer at the time of heating at a 2nd level, and the convex amount of a thermal expansion layer. It is sectional drawing which shows the outline | summary of the thermally expansible sheet which concerns on Embodiment 2. FIG. It is sectional drawing which shows the outline | summary of the manufacturing method of the thermally expansible sheet which concerns on Embodiment 2. FIG. It is sectional drawing which shows the outline | summary of the thermally expansible sheet which concerns on Embodiment 3. FIG. It is sectional drawing which shows the outline | summary of the manufacturing method of the thermally expansible sheet which concerns on Embodiment 3. FIG. It is sectional drawing which shows the outline | summary of the thermally expansible sheet which concerns on a modification. It is sectional drawing which shows the outline | summary of the thermally expansible sheet which concerns on a modification.

  Hereinafter, a thermally expandable sheet and a method for producing a thermally expandable sheet according to an embodiment of the present invention will be described in detail with reference to the drawings.

(Embodiment 1)
As shown in FIG. 1, the thermally expandable sheet 10 according to Embodiment 1 includes a base material 11, an anchor layer 12, a thermally expandable layer 13, a first ink receiving layer 14, and a second ink receiving layer 15. In addition, as will be described in detail later, the thermally expandable sheet 10 is a three-dimensional image forming system 70 schematically shown in FIGS. Image) is formed.

  The base material 11 is a sheet-like member that supports the thermal expansion layer 13 and the like. As the base material 11, a generally used resin sheet-like member (film) can be appropriately selected and used. As the base material 11, a sheet-like material including a polyolefin resin such as polyethylene or polypropylene, a polyester resin, a polyamide resin such as nylon, a polyvinyl chloride resin, a polyimide resin, a silicone resin, or the like is used. be able to. Further, the base material 11 does not protrude on the opposite side of the base material 11 (the lower side shown in FIG. 1) when the thermal expansion layer 13 is expanded entirely or partially by foaming, and wrinkles are generated. It is strong enough not to wave greatly. In addition, it has heat resistance enough to withstand heating when the thermal expansion layer is foamed. Furthermore, the base material 11 may have elasticity in addition to the above strength and heat resistance.

  As will be described later, in the present embodiment, a sheet-like member in which the ink receiving layer and the sheet are integrally formed can be used as the substrate 11. Specifically, the thermally expandable sheet 10 is manufactured using a sheet-like member having an ink receiving layer on the uppermost surface (outermost surface) of a sheet (film) formed of the above-described material as the base material 11. You can also. When such a sheet is used as the base material 11, the ink receiving layer provided on the base material 11 is used as the second ink receiving layer 15.

  The anchor layer 12 is provided on one surface (the upper surface shown in FIG. 1) of the base material 11, and the thermal expansion layer 13 is provided on the anchor layer 12. The anchor layer 12 is a layer having good adhesion to both the base material 11 and the thermal expansion layer 13. The anchor layer 12 has a function of increasing the adhesive force between the base material 11 and the thermal expansion layer 13. By providing the anchor layer 12, it is possible to prevent the lower surface of the thermal expansion layer 13 from peeling from the base material 11 when the thermal expansion layer 13 is foamed and expanded.

  The anchor layer 12 is a layer containing a material having good adhesion to the base material 11 and the thermal expansion layer 13. Specifically, the anchor layer 12 includes at least one resin selected from the group consisting of polyester, acrylic, polyurethane, or any copolymer thereof. For example, the resin contained in the anchor layer 12 may include, for example, only a polyester resin, or may include a polyester resin and a polyurethane resin. Further, the resin contained in the anchor layer 12 may be modified with a modifying agent. In particular, in the present embodiment, the anchor layer 12 preferably includes a polyester / acryl / urethane composite resin. In addition, although not restricted to this, As an aqueous dispersion liquid containing a polyester-acrylic-urethane composite resin, "WAC-17XC" by Takamatsu Yushi Co., Ltd., etc. are mentioned.

  In the present embodiment, the anchor layer 12 is not limited to being formed from the above-described material, but includes a surface modification layer formed by performing corona treatment on the surface of the base material 11. Specifically, the surface modification layer is formed using a corona treatment device 60 shown in FIG. This surface modified layer is a layer having improved adhesion to the thermal expansion layer 13 as compared with the unmodified substrate 11. Since the surface modification layer adheres well to the thermal expansion layer 13, it is possible to suppress peeling of the thermal expansion layer 13 when the thermal expansion layer 13 is expanded.

  The thermal expansion layer 13 is formed on the anchor layer 12 provided on one surface (the upper surface in FIG. 1) of the substrate 11 in contact with the anchor layer 12. The thermal expansion layer 13 is a layer that expands to a size corresponding to the heating temperature and the heating time, and a plurality of thermally expandable materials (thermally expandable microcapsules and microcapsules) are dispersedly arranged in the binder. Further, as will be described in detail later, in the present embodiment, the photothermal conversion layer is formed on the first ink receiving layer 14 provided on the upper surface (front surface) of the base material 11 and / or on the lower surface (back surface) of the base material 11. The region where the photothermal conversion layer is provided is heated by irradiating with light. Since the thermal expansion layer 13 expands by absorbing heat generated by the photothermal conversion layer on the front surface and / or back surface, only a specific region of the thermally expandable sheet can be selectively expanded.

  As the binder, a thermoplastic resin such as a vinyl acetate polymer or an acrylic polymer is used. Further, the thermally expandable microcapsule contains propane, butane, or other low boiling point vaporizable substance in the shell of the thermoplastic resin. The shell is formed of a thermoplastic resin such as polystyrene, polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, polyacrylate, polyacrylonitrile, polybutadiene, or a copolymer thereof. The average particle size of the thermally expandable microcapsule is about 5 to 50 μm. When this microcapsule is heated to a temperature higher than the thermal expansion start temperature, the polymer shell made of resin is softened, the encapsulated low-boiling vaporizable substance is vaporized, and the capsule expands due to the pressure. Although depending on the characteristics of the microcapsule used, the microcapsule expands to about 5 times the particle size before expansion. Note that there is a variation in the particle size of the microcapsules, and not all the microcapsules have the same particle size.

  The first ink receiving layer 14 is formed on the thermal expansion layer 13. The first ink receiving layer 14 is a layer that receives and fixes ink used in the printing process, for example, ink of an ink jet printer. The ink receiving layer 14 is formed using a widely used material according to the ink used in the printing process. For example, in the case of using water-based ink and receiving ink using a void, the first ink receiving layer 14 is formed using, for example, porous silica. In the type that swells and receives ink, the first ink receiving layer 14 is formed using a resin selected from the group consisting of, for example, polyvinyl alcohol (PVA), polyester, polyurethane, and acrylic. The Note that the first ink receiving layer 14 is omitted if the ink can be directly fixed on the thermal expansion layer 13 according to the printing method, such as when an ultraviolet curable ink is used in the inkjet method. It is possible. Further, the first ink receiving layer 14 can be omitted even when there is no need to print on the surface of the thermally expandable sheet 10 depending on the method of forming a stereoscopic image and / or the use of the thermally expandable sheet. is there.

  The second ink receiving layer 15 is formed on the other surface (the lower surface shown in FIG. 1) of the substrate 11. The second ink receiving layer 15 is a layer that receives and fixes ink used in the printing process, for example, ink of an inkjet printer, in the same manner as the first ink receiving layer 14. The second ink receiving layer 15 is formed using the same material as that of the first ink receiving layer 14. In this embodiment, since a resin film is used as the base material 11, it is a layer necessary for fixing the ink constituting the photothermal conversion layer on the back surface (the lower surface shown in FIG. 1) of the base material 11. Note that the second ink receiving layer 15 can be omitted when the photothermal conversion layer is not formed on the back surface.

(Method for producing thermally expandable sheet)
Next, the manufacturing method of the thermally expansible sheet 10 is demonstrated using Fig.2 (a)-FIG.2 (d).
First, a resin sheet-like material such as a film made of polyethylene terephthalate (PET) is prepared as the substrate 11. The base material 11 may be a roll shape or may be cut in advance.

  First, in order to form the second ink receiving layer 15 on the back surface of the substrate 11 (the lower surface shown in FIG. 2A), the material constituting the second ink receiving layer 15 such as porous silica or PVA is used. The selected material is dispersed in a solvent to prepare a coating solution. Subsequently, this coating solution is applied onto the back surface of the substrate 11 using a known coating apparatus such as a bar coater, a roller coater, or a spray coater. Subsequently, the coating film is dried to form a second ink receiving layer 15 as shown in FIG. In addition, by using a PET film in which the ink receiving layer is formed on the outermost surface such as an OHP (Overhead projector) sheet, a sheet in which the second ink receiving layer 15 is previously formed on the back surface of the substrate 11. It is also possible to omit the step of forming the second ink receiving layer 15.

  Next, in order to form the anchor layer 12 on one surface of the base material 11 (the upper surface shown in FIG. 2A), from the group consisting of polyester, acrylic, polyurethane, or any copolymer thereof. A coating liquid (for example, an aqueous dispersion) containing at least one selected resin is prepared. Subsequently, the coating liquid is applied onto the substrate 11 using a known coating apparatus such as a bar coater, a roller coater, or a spray coater. Subsequently, the coating film is dried to form the anchor layer 12 as shown in FIG.

  In the step of forming the anchor layer 12, instead of the above, a corona treatment may be performed using a corona treatment device 60 schematically shown in FIG. As shown in FIG. 3, the corona treatment device 60 is a so-called roll-to-roll treatment device, and includes a treatment roll 61, an electrode 62, and a guide roll 63. The base material 11 before processing is guided to the processing roll 61 by the guide roll 63. When a high-frequency high voltage is applied between the processing roll 61 and the electrode 62 from a high-frequency power supply device (not shown), corona discharge is generated between the processing roll 61 and the electrode 62 in a region indicated by a broken line in FIG. Will occur. When the base material 11 passes under this corona discharge region, the surface of the base material 11 is subjected to corona treatment, and a surface modification layer (anchor layer 12) is formed on the base material 11. Further, the corona treatment device 60 is not limited to the roll-to-roll method, and may be a single wafer type.

  Next, a binder made of a thermoplastic resin or the like and a thermally expandable material (thermally expandable microcapsule) are mixed to prepare a coating solution for forming the thermally expandable layer 13. Subsequently, the coating solution is applied onto the anchor layer 12 using a known coating device such as a bar coater, a roller coater, or a spray coater. Subsequently, the coating film is dried to form a thermal expansion layer 13 as shown in FIG. In addition, in order to obtain the target thickness of the thermal expansion layer 13, the coating liquid may be applied and dried a plurality of times.

  Next, a coating liquid is prepared using a material constituting the first ink receiving layer 14, for example, a material selected from porous silica, PVA and the like. Subsequently, this coating solution is applied onto the thermal expansion layer 13 using a known coating apparatus such as a bar coater, a roller coater, or a spray coater. In order to obtain the target thickness of the first ink receiving layer 14, the coating liquid may be applied and dried a plurality of times. Subsequently, the coating film is dried to form the first ink receiving layer 14 as shown in FIG. When the roll-shaped base material 11 is used, it is cut into a size suitable for the stereoscopic image forming system 70.

The thermally expandable sheet 10 is manufactured by the above process.
The step of forming the second ink receiving layer 15 may be performed after the anchor layer 12, the thermal expansion layer 13, and the first ink receiving layer 14 are formed.

(3D image forming system)
Next, the three-dimensional image forming system 70 that forms a three-dimensional image on the thermally expandable sheet 10 of the present embodiment will be described. As shown in FIGS. 4A to 4C, the stereoscopic image forming system 70 includes a control unit 71, a printing unit 72, an expansion unit 73, a display unit 74, a top board 75, and a frame 80. And comprising. 4A is a front view of the stereoscopic image forming system 70, FIG. 4B is a plan view of the stereoscopic image forming system 70 in a state where the top plate 75 is closed, and FIG. FIG. 3 is a plan view of the stereoscopic image forming system 70 in a state where the top plate 75 is opened. 4A to 4C, the X direction is the same as the horizontal direction, the Y direction is the same as the conveyance direction D in which the sheet is conveyed, and the Z direction is the same as the vertical direction. is there. The X direction, the Y direction, and the Z direction are orthogonal to each other.

  The control unit 71, the printing unit 72, and the expansion unit 73 are each placed in the frame 80 as shown in FIG. Specifically, the frame 80 includes a pair of substantially rectangular side plates 81 and a connecting beam 82 provided between the side plates 81, and a top plate 75 is passed above the side plates 81. Further, a printing unit 72 and an expansion unit 73 are installed side by side in the X direction on the connecting beam 82 passed between the side plates 81, and the control unit 71 is fixed below the connecting beam 82. The display unit 74 is embedded in the top plate 75 so that the height coincides with the top surface of the top plate 75.

  The control unit 71 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like, and controls the printing unit 72, the expansion unit 73, and the display unit 74.

  The printing unit 72 is an ink jet printing apparatus. As shown in FIG. 4C, the printing unit 72 includes a carry-in part 72 a for carrying in the thermally expandable sheet 10 and a discharge part 72 b for discharging the thermally expandable sheet 10. The printing unit 72 prints the designated image on the front or back surface of the thermally expandable sheet 10 carried in from the carry-in section 72a, and discharges the thermally expandable sheet 10 on which the image has been printed, from the discharge section 72b. The printing unit 72 includes color inks (cyan (C), magenta (M), yellow (Y)) for forming a color ink layer 92, which will be described later, and a front side photothermal conversion layer 91 and a back side photothermal conversion layer. And black ink (including carbon black). In order to form a black or gray color in the color ink layer 92, a black color ink not containing carbon black may be further provided as the color ink.

  The printing unit 72 acquires color image data indicating a color image (color ink layer 92) to be printed on the surface of the thermally expandable sheet 10 from the control unit 71, and based on the color image data, the color ink (cyan, magenta, A color image (color ink layer 92) is printed using yellow. The black or gray color of the color ink layer 92 is formed by mixing three colors of CMY or further using black color ink not containing carbon black.

  Moreover, the printing unit 72 prints the front side photothermal conversion layer 91 using black ink based on the surface foaming data which is data indicating the portion to be foamed and expanded on the surface of the thermally expandable sheet 10. Similarly, the back side photothermal conversion layer 93 is printed using black ink based on back surface foaming data, which is data indicating a portion to be foamed and expanded on the back surface of the thermally expandable sheet 10. Black ink containing carbon black is an example of a material that converts light into heat. The expansion height of the thermal expansion layer 13 increases as the portion of the black ink having a higher density is formed. For this reason, the density of the black ink is determined so as to correspond to the target height.

  The expansion unit 73 is an expansion device that applies heat to the thermally expandable sheet 10 to expand it. As shown in FIG. 4C, the expansion unit 73 includes a carry-in part 73 a for carrying in the thermally expandable sheet 10 and a discharge part 73 b for discharging the thermally expandable sheet 10. The expansion unit 73 applies heat to the thermally expandable sheet 10 carried in from the carry-in part 73a to expand it, and discharges the expanded thermally expandable sheet 10 from the discharge part 73b. The expansion unit 73 includes an irradiation unit (not shown) inside. An irradiation part is a halogen lamp, for example, and is a near infrared region (wavelength 750-1400 nm), visible light region (wavelength 380-750 nm), or mid-infrared region (wavelength 1400-4000 nm) with respect to the thermally expandable sheet 10. ). When light is applied to the thermally expandable sheet 10 on which black ink containing carbon black is printed, light is converted into heat more efficiently in the area where the black ink is printed than in the area where the black ink is not printed. Is done. Therefore, the area of the thermal expansion layer 13 where the black ink is printed is mainly heated. As a result, the thermally expandable material in the region where the black ink is printed foams, and the thermally expandable layer 13 expands.

  The display unit 74 includes a touch panel or the like. For example, as shown in FIG. 4B, the display unit 74 displays an image (star shown in FIG. 4B) printed on the thermally expandable sheet 10 by the printing unit 72. The display unit 74 displays an operation guide or the like, and the user can operate the stereoscopic image forming system 70 by touching the display unit 74.

(Stereoscopic image formation processing)
Next, referring to the flowchart shown in FIG. 5 and the cross-sectional views of the thermally expandable sheet 10 shown in FIGS. 6A to 6E, the stereoscopic image forming system 70 applies a stereoscopic image to the thermally expandable sheet 10. A flow of processing to be formed will be described.

  First, the user prepares the thermally expandable sheet 10 before the stereoscopic image is formed, and designates color image data, front surface foam data, and back surface foam data via the display unit 74. Then, the thermally expandable sheet 10 is inserted into the printing unit 72 with its surface facing upward. The printing unit 72 prints the photothermal conversion layer (front side photothermal conversion layer 91) on the surface of the inserted thermally expandable sheet 10 (step S1). The front side photothermal conversion layer 91 is a layer formed of a material that converts light into heat, specifically, black ink containing carbon black. The printing unit 72 ejects black ink containing carbon black onto the surface of the thermally expandable sheet 10 in accordance with the designated surface foaming data. As a result, as shown in FIG. 6A, the front side photothermal conversion layer 91 is formed on the first ink receiving layer 14. For ease of understanding, the front-side photothermal conversion layer 91 is illustrated as being formed on the first ink receiving layer 14, but more precisely black ink is used for the first ink receiving layer 14. Therefore, the photothermal conversion layer is formed in the first ink receiving layer 14.

  Second, the user inserts the thermally expandable sheet 10 on which the light-to-heat conversion layer 91 is printed into the expansion unit 73 with the surface thereof facing upward. The expansion unit 73 heats the inserted thermally expandable sheet 10 by irradiating light from the surface (step S2). If demonstrating it concretely, the expansion | swelling unit 73 will irradiate light to the surface of the thermally expansible sheet 10 by an irradiation part. The front side photothermal conversion layer 91 printed on the surface of the thermally expandable sheet 10 generates heat by absorbing the irradiated light. As a result, as shown in FIG. 6B, the region where the front side photothermal conversion layer 91 of the thermally expandable sheet 10 is printed rises and expands. In FIG. 6B, when the density of the black ink of the front side photothermal conversion layer 91 shown on the right is made higher than that of the front side photothermal conversion layer 91 shown on the left, as shown in FIG. It becomes possible to inflate higher.

  Third, the user inserts the thermally expandable sheet 10 whose surface is heated and expanded into the printing unit 72 with the surface facing upward. The printing unit 72 prints a color image (color ink layer 92) on the surface of the inserted thermally expandable sheet 10 (step S3). Specifically, the printing unit 72 ejects cyan C, magenta M, and yellow Y ink onto the surface of the thermally expandable sheet 10 in accordance with designated color image data. As a result, as shown in FIG. 6C, a color ink layer 92 is formed on the first ink receiving layer 14 and the front side photothermal conversion layer 91.

  Fourth, the user inserts the thermally expandable sheet 10 on which the color ink layer 92 is printed into the expansion unit 73 with the back surface thereof facing upward. The expansion unit 73 heats the inserted thermally expandable sheet 10 from the back surface, and dries the color ink layer 92 formed on the surface of the thermally expandable sheet 10 (step S4). More specifically, the expansion unit 73 irradiates the back surface of the thermally expandable sheet 10 with light by the irradiation unit, heats the color ink layer 92, and volatilizes the solvent contained in the color ink layer 92.

  Fifth, the user inserts the thermally expandable sheet 10 on which the color ink layer 92 is printed into the printing unit 72 with the back surface thereof facing up. The printing unit 72 prints the photothermal conversion layer (back side photothermal conversion layer 93) on the back surface of the inserted thermally expandable sheet 10 (step S5). Similar to the photothermal conversion layer 91 printed on the front side of the thermally expandable sheet 10, the back side photothermal conversion layer 93 is a layer formed of a material that converts light into heat, specifically black ink containing carbon black. is there. The printing unit 72 ejects black ink containing carbon black on the back surface of the thermally expandable sheet 10 according to the specified back surface foaming data. As a result, a back side photothermal conversion layer 93 is formed on the back surface of the substrate 11 as shown in FIG. Also for the back side photothermal conversion layer 93, when the density of the black ink of the back side photothermal conversion layer 93 shown on the right is made higher than that of the back side photothermal conversion layer 93 shown on the left, the darkly printed region becomes higher as shown in the figure. It can be inflated.

  Sixth, the user inserts the thermally expandable sheet 10 on which the back side light-to-heat conversion layer 93 is printed into the expansion unit 73 with its back surface facing upward. The expansion unit 73 heats the inserted thermally expandable sheet 10 by irradiating light from the back surface (step S6). If demonstrating it concretely, the expansion | swelling unit 73 will irradiate light to the back surface of the thermally expansible sheet 10 by an irradiation part (not shown). The back side photothermal conversion layer 93 printed on the back surface of the thermally expandable sheet 10 generates heat by absorbing the irradiated light. As a result, as shown in FIG.6 (e), the area | region where the back side photothermal conversion layer 93 of the thermally expansible sheet 10 was printed rises and expand | swells.

  A three-dimensional image is formed on the thermally expandable sheet 10 by the procedure as described above.

  The photothermal conversion layer may be formed only on the front side or only on the back side. In the case where the photothermal conversion layer is printed only on the front side, steps S1 to S4 are performed among the above processes. On the other hand, when the photothermal conversion layer is formed only on the back side, steps S3 to S6 are performed in the above processing.

  According to the thermally expandable sheet 10 and the method for manufacturing the thermally expandable sheet 10 of the present embodiment, the anchor layer 12 is provided between the substrate 11 and the thermally expandable layer 13, so that the resin sheet is used as the substrate 11. Even when the thermal expansion layer 13 is used, it is possible to prevent the thermal expansion layer 13 from peeling from the base material 11 when the thermal expansion layer 13 is expanded.

  Further, in the method for manufacturing the thermally expandable sheet 10, the base 11 having an ink receiving layer formed in advance on any surface is used, and the ink receiving layer formed in advance is used as the second ink receiving layer 15. As a result, the manufacturing process can be simplified.

(Example)
Next, as an example, a thermally expandable sheet in which an anchor layer is formed on a base material and a thermal expansion layer is further formed on the anchor layer as in this embodiment, and as a comparative example, an anchor layer is not provided. An example in which a thermally expandable sheet having a thermally expanded layer formed on a substrate is heated and expanded will be described. In both the examples and comparative examples, polyethylene terephthalate (PET) having a thickness of 100 μm was used as the base material. Further, “WAC-17XC” manufactured by Takamatsu Yushi Co., Ltd. was used as the anchor layer, and the anchor layer was formed to a thickness of several μm. The thermal expansion layer was formed under the same conditions in both the example and the comparative example.

  Photothermal conversion layers having different black densities were formed on the surfaces of these thermally expandable sheets. The black density is the density of black (K) on the color data when the photothermal conversion layer is printed. K100 is so-called solid black (K100%). For K10, K20, K30, K40, K50, K60, K70, K80 and K90, the density of black (K) on the color data is 10%, 20%, 30%, 40%, 50% and 60%, respectively. , 70%, 80% and 90%. The photothermal conversion layer was formed only on the front side of the thermally expandable sheet, and the photothermal conversion layers were all formed in the same shape.

  Two levels were set as the heating amount (light irradiation amount). First, the amount of heating is large, and in both the example and the comparative example, the level where peeling occurs in the region where the black density is high (FIG. 7A), and the second is peeling only in one of the example and the comparative example. The resulting level (FIG. 7B). The thermally expandable sheets of Examples and Comparative Examples were irradiated with light at these two levels, the thermally expanded layer was foamed and expanded, and the expansion height (convex amount) of the thermally expanded layer was measured. In addition, since light is irradiated on the same conditions with respect to the photothermal conversion layer of the different density | concentration provided on the thermally expansible sheet, it will generate | occur | produce heat | fever more as the photothermal conversion layer with high black density. Therefore, the region where the photothermal conversion layer having a high black density in the thermal expansion layer is formed is heated more.

  FIG. 7A shows the convex amount (mm) of the thermally expandable sheets of the example and the comparative example at the first level (high heating amount). In the example, peeling of the thermal expansion layer occurred at K100. However, as shown in FIG. 7A, the thermal expansion layer was not peeled up to K90, and a convex amount corresponding to the heating amount was obtained. On the other hand, in the comparative example, peeling did not occur until K60, but peeling occurred after K70.

  Next, in FIG.7 (b), the convex amount (mm) of the thermally expansible sheet of an Example and a comparative example in a 2nd level (small heating amount) is shown. In the example, as shown in FIG. 7A, the thermal expansion layer was not peeled up to K100, and a convex amount corresponding to the heating amount was obtained. On the other hand, in the comparative example, peeling did not occur until K60, but peeling occurred after K70.

  Thus, from FIG. 7A and FIG. 7B, it became clear that, in the example, by providing the anchor layer, the adhesion between the base material and the thermal expansion layer is increased, and peeling can be suppressed. . Further, until the peeling occurred in both the example and the comparative example, the convex amount increased by drawing substantially the same curve, and it was also clear that the anchor layer did not particularly affect the expansion of the thermal expansion layer.

(Embodiment 2)
A thermally expandable sheet 20 according to Embodiment 2 is shown in FIG. The heat-expandable sheet 20 of the second embodiment is different from the heat-expandable sheet 10 of the first embodiment in that the ink receiving layer is used as the anchor layer 22. Constituent elements similar to those of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 8, the thermally expandable sheet 20 includes a base material 11, an anchor layer 22, a thermally expandable layer 13, and a first ink receiving layer 14. The base material 11, the thermal expansion layer 13, and the first ink receiving layer 14 are the same as those of the thermal expansion sheet 10 according to the first embodiment.

  In the present embodiment, the configuration including only the first ink receiving layer 14 is taken as an example, and thus the photothermal conversion layer is formed only on the front side. Accordingly, the stereoscopic image forming process performs steps S1 to S4 of the flowchart shown in FIG. The thermally expandable sheet 20 may include a second ink receiving layer 15 on the back surface of the base material 11 as in the first embodiment. In this case, the same three-dimensional image forming process as in the first embodiment (steps S1 to S6 in the flowchart shown in FIG. 5) is performed.

  The anchor layer 22 of the present embodiment is formed of a material capable of receiving and fixing ink of an ink jet printer, similarly to the material used as the first ink receiving layer 14. Furthermore, the anchor layer 22 has good adhesion to the material constituting the thermal expansion layer 13. As the anchor layer 22, for example, one or a plurality of resins selected from the group consisting of polyvinyl alcohol (PVA), polyester, polyurethane, acrylic, etc., used as a type that swells and receives ink are used. Can be used. Although these materials can swell and accept ink, they also have good adhesiveness with the material constituting the thermal expansion layer 13. For this reason, it can function as the anchor layer 22. As the anchor layer 22, any material can be used as long as it is a material used for receiving ink and has good adhesion to the thermal expansion layer 13 in addition to the materials described above.

(Method for producing thermally expandable sheet)
Next, a method for manufacturing the thermally expandable sheet 20 will be described with reference to FIGS.
First, a sheet-like material such as a film made of PET is prepared as the substrate 11. The base material 11 may be a roll shape or may be cut in advance.

  First, one or a plurality of materials selected from materials constituting the anchor layer 22 on the surface of the substrate 11 (upper surface shown in FIG. 9A), for example, PVA, polyester resin, polyurethane resin, acrylic resin, and the like. A coating solution is prepared using the material. Subsequently, this coating solution is applied onto the substrate 11 using a known coating apparatus such as a bar coater, a roller coater, or a spray coater. Subsequently, the coating film is dried to form the anchor layer 22 as shown in FIG. In addition, when a sheet (for example, an OHP film) in which an ink receiving layer made of the above-described material is formed on the surface of the substrate 11 in advance is used, the ink receiving layer formed in advance may be used as the anchor layer 22. it can. Thereby, the step of forming the anchor layer 22 can be omitted, which is preferable.

  Next, as in the first embodiment, the thermal expansion layer 13 is formed on the anchor layer 22 using a binder made of a thermoplastic resin or the like and a thermal expansion material (thermal expansion microcapsule). Subsequently, a first ink receiving layer 14 is formed on the thermal expansion layer 13. When the roll-shaped substrate 11 is used, it is cut into a size suitable for the stereoscopic image forming system 70.

The thermally expandable sheet 20 is manufactured by the above process.
In addition to the above steps, the step of forming the second ink receiving layer 15 on the back surface of the substrate 11 may be further performed as in the first embodiment.

  According to the thermally expandable sheet 20 and the method of manufacturing the thermally expandable sheet 20 of the present embodiment, the layer used as the ink receiving layer functions as the anchor layer 22, so that the thermal expansion is performed when the thermal expansion layer 13 is expanded. It can suppress that the layer 13 peels from the base material 11. FIG. In particular, when a sheet having an ink receiving layer formed in advance on either surface of the substrate 11 is used, the process of forming the anchor layer 22 can be omitted, and the manufacturing process can be simplified. It is preferable.

  In addition, for example, the first embodiment and the second embodiment have different layer configurations, but a substrate having an ink receiving layer formed on the outermost surface (uppermost surface) of any surface is obtained, and this substrate is used. If other layers are originally formed, the members can be shared among different embodiments. For example, a substrate having an ink receiving layer on the outermost surface of one surface is prepared. When this ink receiving layer is used as the second ink receiving layer 15 in the first embodiment and the anchor layer 12, the thermal expansion layer 13 and the like are formed on the other surface, the thermally expandable sheet 10 of the first embodiment is manufactured. be able to. On the other hand, when the pre-formed ink receiving layer has good adhesion with the thermal expansion layer, this layer is used as the anchor layer 22 and the thermal expansion layer 13 and the like are formed on the anchor layer 22. The thermally expandable sheet 20 according to Embodiment 2 can be manufactured. Therefore, according to the manufacturing method of this embodiment, in the manufacturing method of the thermally expansible sheet from which the structure of a layer differs, the effect that a member can be made shared is preferable.

(Embodiment 3)
A thermally expandable sheet 30 according to Embodiment 3 is shown in FIG. The thermally expandable sheet 30 according to Embodiment 3 is different from the thermally expandable sheet 10 of Embodiment 1 in that an anchor layer 32 is formed on the third ink receiving layer 31. Constituent elements similar to those of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 10, the thermally expandable sheet 30 includes a base material 11, a third ink receiving layer 31, an anchor layer 32, a thermally expandable layer 13, and a first ink receiving layer 14. The thermally expandable sheet 20 may include a second ink receiving layer 15 on the back surface of the base material 11 as in the first embodiment.

  The third ink receiving layer 31 is formed of a material capable of receiving and fixing ink of an ink jet printer in the same manner as the material constituting the first ink receiving layer 14. Unlike the anchor layer 22 of the second embodiment, the third ink receiving layer 31 is a layer that can receive the ink of the ink jet printer. However, the third ink receiving layer 31 is more adhesive to the thermal expansion layer 13 than the anchor layer 22. It is a low layer. For example, the third ink receiving layer 31 is made of porous silica or the like that uses voids.

  The anchor layer 32 is formed of the same material as the anchor layer 12 of the first embodiment, and has good adhesion to the third ink receiving layer 31 and the thermal expansion layer 13. By providing the anchor layer 32 on the third ink receiving layer 31, the third ink receiving layer 31 and the thermal expansion layer 13 are bonded well, and when the thermal expansion layer 13 is expanded, the thermal expansion layer 13 is expanded. Can be prevented from peeling from the substrate 11.

(Method for producing thermally expandable sheet)
Next, the manufacturing method of the thermally expansible sheet 30 is demonstrated using FIG. 11 (a)-FIG.
First, a resin sheet, for example, a film made of PET is prepared as the substrate 11. The base material 11 may be a roll shape or may be cut in advance.

  A coating liquid is prepared using a material constituting the third ink receiving layer 31, for example, porous silica or the like, on the surface of the substrate 11 (shown in FIG. 11A). Subsequently, this coating solution is applied onto the substrate 11 using a known coating apparatus such as a bar coater, a roller coater, or a spray coater. Subsequently, the coating film is dried to form a third ink receiving layer 31 as shown in FIG. If a sheet (for example, an OHP film) on which the ink receiving layer composed of the above-described material is formed in advance is used, the step of forming the third ink receiving layer 31 on the substrate 11 is omitted. This is preferable.

  Next, in order to form the anchor layer 32 on the third ink receiving layer 31, a coating liquid containing a material used as the anchor layer 32 is prepared. The anchor layer 32 is selected from materials used as the anchor layer 12 shown in the first embodiment. Subsequently, the coating liquid is applied onto the substrate 11 using a known coating apparatus such as a bar coater, a roller coater, or a spray coater. Next, the coating film is dried to form the anchor layer 32 as shown in FIG.

  Next, as in Embodiment 1, using a binder made of a thermoplastic resin and the like and a thermally expandable material (thermally expandable microcapsule), as shown in FIG. Form on layer 32. Subsequently, as shown in FIG. 11D, a first ink receiving layer 14 is formed on the thermal expansion layer 13. When the roll-shaped substrate 11 is used, it is cut into a size suitable for the stereoscopic image forming system 70.

The thermally expandable sheet 30 is manufactured through the above steps.
In addition to the above steps, a step of forming the second ink receiving layer 15 on the back surface of the substrate 11 may be further performed.

  According to the thermally expandable sheet 30 and the method of manufacturing the thermally expandable sheet 30 of the present embodiment, the anchor layer 32 is provided on the third ink receiving layer 31, so that the third ink receiving layer 31 and the thermal expansion sheet 30 are thermally expanded. When the layer 13 adheres well and the thermal expansion layer 13 is expanded, the thermal expansion layer 13 can be prevented from peeling off. In addition, for example, a plastic film such as PET used in Embodiment 1 is used as the base material 11 and a sheet having an ink receiving layer formed in advance on any surface of the base material 11 is obtained. If the anchor layer 32 is formed on the third ink receiving layer 31 by using as the third ink receiving layer 31, the manufacturing process can be simplified.

  In addition, for example, Embodiment 1 and Embodiment 3 have different layer configurations, but a substrate having an ink-receiving layer formed on either surface is obtained, and other layers based on this substrate are obtained. If it forms, it becomes possible to make a member common between different embodiment. For example, a substrate having an ink receiving layer on one side is prepared. If this ink receiving layer is used as the second ink receiving layer 15 in the first embodiment and an anchor layer, a thermal expansion layer or the like is formed on the other surface, the thermally expandable sheet 10 of the first embodiment can be manufactured. it can. On the other hand, when an ink receiving layer provided in advance is used as the third ink receiving layer 31 and this layer has low adhesion to the thermal expansion layer, an anchor layer is formed on the third ink receiving layer 31. If the thermal expansion layer etc. are provided on the anchor layer 32 by forming 32, the thermal expansion sheet 30 according to the third embodiment can be manufactured. Therefore, according to the manufacturing method of this embodiment, components can be shared in the manufacturing method of a thermally expandable sheet having a different layer structure, which is preferable.

The present invention is not limited to the above-described embodiments, and various applications are possible.
In each of the above-described embodiments, a configuration in which the second ink receiving layer 15 is provided on the back surface of the base material 11 or a configuration in which the second ink receiving layer 15 is not provided is given as an example. The back surface of the material 11 may include an adhesive layer and release paper. By providing the adhesive layer and the release paper, the thermally expandable sheet on which the stereoscopic image is printed can be attached to various objects such as a container.

  For example, the thermally expandable sheet 40 shown in FIG. 12 is obtained by providing an adhesive layer 45 and a release paper 46 on the back surface of the thermally expandable sheet 20 shown in the second embodiment. In this case, as shown in FIG. 12, the thermally expandable sheet 40 includes a base material 11, an anchor layer 22, a thermally expandable layer 13, a first ink receiving layer 14, an adhesive layer 45, and a release paper 46. The adhesive layer 45 is an adhesive that is generally used, and is appropriately selected according to an object to which the thermally expandable sheet 40 is attached. The release paper 46 is formed of a material generally used as a mount such as a seal. Further, the release paper 46 is not limited to paper but may be a film. As in the second embodiment, the anchor layer 22 is formed from a material that is also used as an ink receiving layer, and is a layer that has good adhesion to the thermal expansion layer 13. Further, the second ink receiving layer 15 may be provided on the release paper 46 (in FIG. 12, the lower surface of the release paper 46).

  Further, when the thermally expandable sheet 40 was manufactured, the ink receiving layer (anchor layer 22) was provided on one surface of the substrate 11, and the adhesive layer 45 and the release paper 46 were provided on the other surface. It is preferable to obtain a sheet and use this sheet to form the thermal expansion layer 13 and the like because the manufacturing process can be simplified.

  Similarly, a thermally expandable sheet 50 shown in FIG. 13 is provided with an adhesive layer 45 and a release paper 46 on the back surface of the thermally expandable sheet 30 shown in the third embodiment. In this case, as shown in FIG. 13, the thermally expandable sheet 50 includes the base material 11, the third ink receiving layer 31, the anchor layer 32, the thermal expansion layer 13, the first ink receiving layer 14, the adhesive layer 45, and A release paper 46 is provided. The adhesive layer 45 is an adhesive that is generally used, and is appropriately selected according to an object to which the thermally expandable sheet 50 is attached. The release paper 46 is formed of a material generally used as a mount such as a seal. The third ink receiving layer 31 is a layer that receives and fixes ink as in the third embodiment, but is a layer that has low adhesion to the thermal expansion layer 13. The anchor layer 32 is a layer having good adhesion to the thermal expansion layer 13 as in the third embodiment, and is a layer having good adhesion to the thermal expansion layer 13. Further, the second ink receiving layer 15 may be provided on the release paper 46 (in FIG. 13, the lower surface of the release paper 46).

  Further, when the thermally expandable sheet 50 is manufactured, an ink receiving layer (third ink receiving layer 31) is provided on one surface of the substrate 11, and the adhesive layer 45 and the release paper 46 are provided on the other surface. It is preferable to obtain a sheet provided with, and use this sheet to form the anchor layer 32, the thermal expansion layer 13 and the like, because the manufacturing process can be simplified.

  In addition, all the figures used in each embodiment are for explaining each embodiment. Therefore, it is not intended that the thickness of each layer of the heat-expandable sheet be interpreted as being limited to be formed at a ratio as shown in the figure. For example, in FIG. 1, the base material 11 is illustrated as being thinner than the thermal expansion layer 13, but the base material 11 is formed to have the same thickness as the thermal expansion layer 13, or is configured to be thicker than the thermal expansion layer 13. It is not excluded. The same applies to the other layers.

  Although several embodiments of the present invention have been described, the present invention is included in the invention described in the claims and the equivalents thereof. Hereinafter, the invention described in the scope of claims of the present application will be appended.

[Appendix 1]
An anchor layer formed on one side of the substrate;
A thermal expansion layer formed on the anchor layer,
The substrate is a film made of resin,
The anchor layer includes at least one resin selected from the group consisting of polyester, acrylic, polyurethane, or any copolymer thereof.
A thermally expandable sheet characterized by that.
[Appendix 2]
The anchor layer includes a polyester / acrylic / urethane composite resin,
The heat-expandable sheet according to Supplementary Note 1, wherein
[Appendix 3]
An ink receiving layer is formed on one surface of the substrate,
The anchor layer is formed on the ink receiving layer;
The heat-expandable sheet according to supplementary note 1 or 2, characterized in that.
[Appendix 4]
Forming an anchor layer on one side of the substrate;
Forming a thermal expansion layer on the anchor layer, and
The substrate is a film made of resin,
In the step of forming the anchor layer,
On one side of the substrate, using at least one resin selected from the group consisting of polyester, acrylic, polyurethane, or any copolymer thereof, or on one side of the substrate An anchor layer is formed by performing corona treatment on
A method for producing a thermally expandable sheet, characterized in that
[Appendix 5]
The resin used in the step of forming the anchor layer is a polyester / acrylic / urethane composite resin,
The manufacturing method of the thermally expansible sheet of Additional remark 4 characterized by the above-mentioned.
[Appendix 6]
On one surface of the substrate, an ink receiving layer is provided,
Forming the anchor layer by applying the resin on the ink receiving layer;
The thermally expandable sheet according to Supplementary Note 4 or 5, wherein

10, 20, 30, 40, 50 ... thermal expansion sheet, 11 ... base material, 12, 22, 32 ... anchor layer, 13 ... thermal expansion layer, 14 ... first Ink receiving layer, 15 ... second ink receiving layer, 31 ... third ink receiving layer, 45 ... adhesive layer, 46 ... release paper, 60 ... corona treatment device, 61. ..Processing rolls 62... Electrodes 63. Guide rollers 70. Stereoscopic image forming system 71... Control unit 72 .. Printing unit 72 a. ... Discharging part, 73 ... Expansion unit, 73a ... Loading part, 73b ... Discharging part, 74 ... Display unit, 75 ... Top plate, 80 ... Frame, 81. ..Side plate, 82 ... Connection beam, 91 ... Front side photothermal conversion layer, 92 ... Color Click layer, 93 ... back photothermal conversion layer

Claims (6)

An anchor layer formed on one side of the substrate;
A thermal expansion layer formed on the anchor layer,
The substrate is a film made of resin,
The anchor layer includes at least one resin selected from the group consisting of polyester, acrylic, polyurethane, or any copolymer thereof.
A thermally expandable sheet characterized by that. The anchor layer includes a polyester / acrylic / urethane composite resin,
The thermally expandable sheet according to claim 1. An ink receiving layer is formed on one surface of the substrate,
The anchor layer is formed on the ink receiving layer;
The thermally expandable sheet according to claim 1, wherein the sheet is thermally expandable. Forming an anchor layer on one side of the substrate;
Forming a thermal expansion layer on the anchor layer, and
The substrate is a film made of resin,
In the step of forming the anchor layer,
On one side of the substrate, using at least one resin selected from the group consisting of polyester, acrylic, polyurethane, or any copolymer thereof, or on one side of the substrate An anchor layer is formed by performing corona treatment on
A method for producing a thermally expandable sheet, characterized in that The resin used in the step of forming the anchor layer is a polyester / acrylic / urethane composite resin,
The manufacturing method of the thermally expansible sheet | seat of Claim 4 characterized by the above-mentioned. On one surface of the substrate, an ink receiving layer is provided,
Forming the anchor layer by applying the resin on the ink receiving layer;
The method for producing a thermally expandable sheet according to claim 4 or 5, wherein:

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