JP2022171108A - Image transfer sheet and image transfer method - Google Patents

Abstract

To provide an image transfer sheet that does not require the use of special materials and that can be manufactured easily.SOLUTION: An image transfer sheet 10 includes a release paper 20, a protective sheet 70 having an adhesive layer 71, an image layer 50 that is a layer in which photocurable process color ink is completely cured and that is provided between the release paper 20 and the protective sheet 70, an overcoat layer 60 that is a layer in which photocurable transparent ink is completely cured and that is provided between the protective sheet 70 and an image layer 50, and is adhered to an adhesive layer 71 of the protective sheet 70, and an adhesive layer 30 that is a layer in which photocurable ink is semi-cured, that has adhesiveness to the material to be transferred, and that is provided between the release paper 20 and the image layer 50.SELECTED DRAWING: Figure 1

Description

The present invention relates to an image transfer sheet and an image transfer method.

2. Description of the Related Art Conventionally, a method of printing an image on an image transfer sheet with a printer and transferring the image on the image transfer sheet to an object to be transferred has been known. Further, the structure of an image transfer sheet for that purpose is also known. For example, Patent Literature 1 discloses an image transfer sheet in which an image layer is formed by a UV printer on release paper on which a peelable adhesive layer is formed, and a transfer film is placed on the image layer. The transfer film has releasability from the image layer and easy adhesion to the glue layer. Therefore, according to Patent Document 1, when the transfer film is peeled off after the adhesive layer of the image transfer sheet from which the release paper has been peeled off is pressure-bonded to the transfer target, the image is transferred to the transfer target, and the glue layer outside the image is transferred. It is peeled off together with the transfer film. According to Patent Document 1, this makes it possible to easily manufacture an image transfer sheet on which only an image can be transferred and printed.

JP 2017-209931 A

The image transfer sheet and image transfer method disclosed in Patent Document 1 include a release paper on which a peelable glue layer is formed, and a transfer film that is releasable from the image layer and easily adheres to the glue layer. A special printing medium is required. On the other hand, the typical conventional method of printing an image on a printing medium with a sticker attached to a release paper and cutting the periphery of the image takes time to cut the printing medium. Hard to say.

SUMMARY OF THE INVENTION An object of the present invention is to provide an image transfer sheet that does not require the use of special materials and is easy to manufacture. Another object of the present invention is to provide a method for producing such an image transfer sheet and transferring an image to a material to be transferred.

The image transfer sheet disclosed herein includes a release paper, a protective sheet having an adhesive layer, and a layer in which a photocurable process color ink is completely cured, and is provided between the release paper and the protective sheet. and an overcoat, which is a layer in which photocurable transparent ink is completely cured, is provided between the protective sheet and the image layer, and is attached to the adhesive layer of the protective sheet. and an adhesive layer, which is a layer in which photocurable ink is semi-cured, has adhesiveness to a transferred material, and is provided between the release paper and the image layer.

The image transfer sheet functions as an image transfer sheet because the image of the image layer can be transferred to the transfer material by adhering the adhesive layer to the transfer material. Moreover, according to the image transfer sheet, since a general-purpose release paper can be used, there is no need to use a special material. Further, the image transfer sheet can be manufactured without cutting, so that it is easy to manufacture.

In the image transfer method disclosed herein, a photocurable ink is ejected by an inkjet printer, and the ink is semi-cured by irradiating light to form an adhesive layer having adhesiveness to a transferred material on a release paper. forming an image layer above the adhesive layer by ejecting a photocurable process color ink with an inkjet printer and irradiating the process color ink with light to completely cure it, and forming an image layer above the adhesive layer; a step of ejecting a photocurable transparent ink with a printer and irradiating the transparent ink with light to completely cure the transparent ink to form an overcoat layer above the image layer; affixing a layer to the overcoat layer; peeling the release paper from the adhesive layer; contacting the adhesive layer after the release paper has been peeled off with a substrate; pressing the protective sheet toward the adhesive layer while the layer is in contact with the substrate; and peeling the protective sheet from the overcoat layer.

According to the above image transfer method, the above image transfer sheet can be produced and used to transfer an image to a material to be transferred.

1 is a schematic cross-sectional view of an image transfer sheet according to a first embodiment; FIG. 4 is a flow chart showing a procedure for producing an image transfer sheet according to the first embodiment; FIG. 4 is a schematic diagram of a step of forming an adhesive layer; FIG. 4 is a schematic diagram of the step of forming an obscuring layer; FIG. 4 is a schematic diagram of the step of forming an image layer; FIG. 4 is a schematic diagram of a step of forming an overcoat layer; 4 is a flow chart showing a procedure of image transfer using an image transfer sheet; It is a schematic diagram of the step of peeling off the release paper. FIG. 4 is a schematic diagram of a bonding step; FIG. 4 is a schematic diagram of a step of peeling off the application sheet; FIG. 5 is a schematic cross-sectional view of an image transfer sheet according to a second embodiment; 9 is a flow chart showing a procedure for producing an image transfer sheet according to the second embodiment; FIG. 4 is a schematic cross-sectional view of the image transfer sheet after image transfer to a transfer material is completed;

Hereinafter, image transfer sheets and image transfer methods according to some embodiments will be described with reference to the drawings. The embodiments described herein are of course not intended to specifically limit the invention. Further, members and parts having the same action are denoted by the same reference numerals, and redundant explanations are omitted or simplified.

[First embodiment]
[Structure of image transfer sheet]
FIG. 1 is a schematic cross-sectional view of an image transfer sheet 10 according to the first embodiment. The image transfer sheet 10 is a sheet that transfers an image to the transfer-receiving material 5 (see FIG. 9) by being adhered to the transfer-receiving material 5 . As shown in FIG. 1, the image transfer sheet 10 includes a release paper 20, an adhesive layer 30 formed on the release paper 20, a concealing layer 40 formed on the adhesive layer 30, and a cover layer 40 formed on the concealing layer 40. an image layer 50 formed thereon; an overcoat layer 60 formed on the image layer 50; and an application sheet 70 attached on the overcoat layer 60.

The release paper 20 is a base material on which the adhesive layer 30 is formed. The release paper 20 is configured so that the adhesive layer 30 can be formed and the adhesive layer 30 can be easily peeled off. The release paper 20 is, for example, a sheet of paper whose surface is subjected to a release treatment. As the release treatment, for example, formation of a silicone resin layer is performed. However, the material of the release paper 20 and the method of surface treatment are not particularly limited. As the release paper 20, a general sticker mount or the like can be suitably used. Although it is called "release paper", the material of the release paper 20 is not limited to paper, and may be, for example, a resin sheet.

The adhesive layer 30 is a layer having adhesive properties, and is adhered to the release paper 20 when the image transfer sheet 10 is not adhered to the material to be transferred 5 . When the image transfer sheet 10 is adhered to the transfer material 5 , the adhesive layer 30 is adhered to the transfer material 5 . The adhesive layer 30 has adhesiveness to the material to be transferred 5 . Here, "having adhesive strength" means, for example, peeling adhesive strength of 0.5 N / 10 mm or more at "peeling angle of 180 degrees, speed of 300 mm / min" specified in JIS Z 0237. . However, the adhesive strength of the adhesive layer 30 is not particularly limited as long as the adhesive strength is at or above the level at which it can generally be said that it "has adhesive strength". In this embodiment, the adhesive layer 30 is made of photocurable white ink. Specifically, the adhesive layer 30 is a layer in which photocurable white ink is semi-cured on the release paper 20 . The photocurable ink is a UV ink containing an ultraviolet curable resin that is cured by being irradiated with ultraviolet rays. However, the components, properties, etc. of the photocurable ink are not particularly limited. The adhesive layer 30 is formed on the release paper 20 by printing with an inkjet printer 100 (hereinafter referred to as the printer 100, see FIG. 3). The printing process will be described later.

The adhesive layer 30 has the same shape as the image layer 50 . This makes it possible to obtain a borderless transfer image, similar to a seal cut around the image. The thickness of the adhesive layer 30 is not particularly limited.

The masking layer 40 is a layer obtained by completely curing photocurable white ink on the adhesive layer 30, and is opaque. The concealing layer 40 has a thickness such that the bottom cannot be seen through. The masking layer 40 is a layer provided so that the image layer 50 can develop a clear color regardless of the color of the material 5 to be transferred. Since the adhesive layer 30 is thin and may not provide sufficient concealment by itself, the concealing layer 40 is provided. Here, the thickness of the concealing layer 40 is thicker than that of the adhesive layer 30 . However, the thickness of the concealing layer 40 is not particularly limited as long as the concealing layer 40 can be made opaque. The concealing layer 40 is also formed by printing with the printer 100 . The concealing layer 40 is also constructed in the same shape as the image layer 50 .

The image layer 50 is a layer forming an image to be transferred onto the transfer material 5 . The image layer 50 is formed on the masking layer 40 . The image layer 50 is a layer in which the process color inks are completely cured on the hiding layer 40 . The process color inks here are photocurable inks. Process color inks include, for example, CMYK (cyan, magenta, yellow, black) inks. However, the color of the process color ink is not particularly limited. The image layer 50 is also formed by printing with the printer 100 .

As shown in FIG. 1, the image layer 50 may be composed of multiple separate portions. A plurality of portions of the image layer 50 separated from each other may constitute images to be transferred to different transfer substrates 5 or different portions of the transfer substrate 5 . That is, the image layer 50 may include a plurality of images with different transferred portions. Further, the image layer 50 may form a three-dimensional image having thickness.

The overcoat layer 60 is a layer for protecting the image layer 50 and is formed on the image layer 50 . The overcoat layer 60 is a layer in which photocurable transparent ink is completely cured on the image layer 50 . The overcoat layer 60 may have a smooth and glossy glossy surface, or may have an uneven surface and may have a matte gloss finish. In addition, the overcoat layer 60 may be formed with a three-dimensional pattern (texture pattern) for imparting a design effect. The overcoat layer 60 is also formed by printing with the printer 100 . The overcoat layer 60 is also constructed in the same shape as the image layer 50 .

The application sheet 70 is a sheet attached on the overcoat layer 60 . The application sheet 70 is an example of a protective sheet that protects the printed layers composed of the adhesive layer 30 , the concealing layer 40 , the image layer 50 and the overcoat layer 60 . The application sheet 70 here is a transparent resin film having an adhesive layer 71 formed on one surface. However, the material and configuration of the application sheet 70 are not particularly limited as long as they can be attached onto the overcoat layer 60 . The application sheet 70 is configured in the same shape as the release paper 20 here. The application sheet 70 is attached by an adhesive layer 71 to the release paper 20 on which the print layer is formed. A portion of the adhesive layer 71 of the application sheet 70 is attached to the overcoat layer 60, and the other portion is attached to a portion of the release paper 20 where the printed layer is not formed. The application sheet 70 and the release paper 20 are members to be removed after the image transfer sheet 10 is transferred to the transferred material 5 . The application sheet 70 and the release paper 20 are provided to improve the convenience of storing, carrying, and transferring the image transfer sheet 10 .

[Method for producing image transfer sheet]
A method for producing the image transfer sheet 10 will be described below. FIG. 2 is a flow chart showing the procedure for producing the image transfer sheet 10 according to this embodiment. As shown in FIG. 2, in the production of the image transfer sheet 10, first, in steps S01 and S02, an adhesive layer 30 having adhesiveness to the material to be transferred 5 is formed on the release paper 20. As shown in FIG. In steps S<b>01 and S<b>02 , the printer 100 ejects photocurable white ink and irradiates the white ink with light to semi-harden it, thereby forming the adhesive layer 30 on the release paper 20 . Specifically, in step S01, the printer 100 ejects photocurable white ink onto the release paper 20. As shown in FIG. In step S02, the white ink ejected onto the release paper 20 is irradiated with light to semi-harden the white ink, thereby forming the adhesive layer 30 having adhesiveness.

FIG. 3 is a schematic diagram showing the steps of forming the adhesive layer 30 (steps S01 and S02). As shown in FIG. 3, the printer 100 includes a flatbed 110, a carriage 120, a recording head 130 mounted on the carriage 120, and two light irradiation devices 141 and 142 also mounted on the carriage 120. ing. The flatbed 110 is a support base that supports the print target. Here, a release paper 20 is placed on the flatbed 110 as a print target. The flatbed 110 is moved in the X direction (perpendicular to the plane of FIG. 3) by a bed moving device (not shown). As the flatbed 110 moves in the X direction, the release paper 20 moves in the X direction. The carriage 120 is moved in the Y direction (horizontal direction in FIG. 3) by a carriage moving device (not shown). As the carriage 120 moves in the Y direction, the recording head 130 and light irradiation devices 141 and 142 mounted on the carriage 120 also move in the Y direction. Note that U and D in FIG. 3 represent upward and downward, respectively. Y1 and Y2 in FIG. 3 each represent one of the Y directions. The X direction, Y direction, and vertical direction are orthogonal to each other. However, these directions are merely directions determined for convenience of explanation, and do not limit the installation mode of the printer 100 in any way, and do not limit the present invention in any way.

As shown in FIG. 3, the print head 130 includes a plurality of ink heads 130W, 130G, 130C, 130M, 130Y and 130K. The ink head 130W is configured to eject photocurable white ink. The ink head 130G is configured to eject photocurable transparent ink. The ink heads 130M to 130K are configured to eject photocurable process color inks. Specifically, the ink head 130C ejects photocurable cyan ink. The ink head 130M ejects photocurable magenta ink. The ink head 130Y ejects photocurable yellow ink. The ink head 130K ejects photocurable black ink. However, process color inks are not limited to CMYK inks. As shown in FIG. 3, the plurality of ink heads 130W to 130K are arranged side by side in the Y direction. Although not shown, each of the plurality of ink heads 130W to 130K extends in the X direction.

The light irradiation devices 141 and 142 are provided on the side surfaces of the carriage 120 in the Y direction. One light irradiation device 141 is arranged in the Y1 direction from the recording head 130 . The other light irradiation device 142 is arranged in the Y2 direction from the recording head 130 . However, the light irradiation device may be provided only in the Y1 direction or the Y2 direction from the recording head 130 . Light irradiation devices 141 and 142 irradiate light for curing the ink ejected from the recording head 130 . The light irradiation devices 141 and 142 are provided with a plurality of ultraviolet irradiation LEDs (not shown) here, and are configured so that the intensity of the irradiated light can be adjusted by turning off some of the ultraviolet irradiation LEDs. However, the method by which the light irradiation devices 141 and 142 adjust the light intensity is not limited to the above. The light irradiation devices 141 and 142 may adjust the light intensity by, for example, adjusting the current flowing through the UV irradiation LEDs.

In the step of forming the adhesive layer 30 (steps S01 and S02), the printer 100 ejects white ink from the ink head 130W toward the release paper 20 on the flatbed 110 while moving the carriage 120 in the Y1 direction. At this time, the light irradiation device 142 on the rear side in the movement direction of the carriage 120 irradiates light with an intensity that does not completely cure the white ink. The white ink that has landed on the release paper 20 is irradiated with light from the light irradiation device 142 . Thereby, the white ink is semi-cured. Since the white ink receives light immediately after landing on the release paper 20, it is semi-cured while still having a grainy feel. Although step S02 is shown after step S01 in FIG. 2, this is for convenience of illustration, and steps S01 and S02 may be performed simultaneously as described above.

The printer 100 repeats the above while changing the relative position between the release paper 20 and the carriage 120 by moving the flatbed 110 in the X direction. As a result, adhesive layers 30 are formed at predetermined locations on the release paper 20 . However, if the adhesive layer 30 is small and it is not necessary to move the flatbed 110, the movement of the flatbed 110 may be omitted. The adhesive layer 30 may be formed of one layer of white ink, or may be formed of a plurality of layers of white ink stacked vertically. In addition, the white ink of the adhesive layer 30 is not semi-cured immediately after landing on the release paper 20, but may be semi-cured after flattening (hereinafter also referred to as leveling) after the passage of time. good.

As shown in FIG. 2, in steps S03 and S04 after the step of forming the adhesive layer 30 (steps S01 and S02), an opaque concealing layer 40 is formed on the adhesive layer 30 by the printer 100 . In steps S<b>03 and S<b>04 , the printer 100 ejects white ink and irradiates the white ink with light to completely cure it, thereby forming the opaque concealing layer 40 on the adhesive layer 30 . Specifically, in step S<b>03 , the printer 100 ejects white ink onto the adhesive layer 30 . In step S<b>04 , the white ink ejected onto the adhesive layer 30 is irradiated with light to completely cure the white ink and form the opaque concealing layer 40 . FIG. 4 is a schematic diagram of the step of forming the masking layer 40 (steps S03 and S04). In steps S03 and S04, white ink is ejected from the ink head 130W toward the adhesive layer 30 while moving the carriage 120 in the Y1 direction, as in steps S01 and S02. At this time, the light irradiation device 141 on the front side in the moving direction of the carriage 120 irradiates light with an intensity sufficient to completely cure the white ink. The white ink that has landed on the adhesive layer 30 is irradiated with light from the light irradiation device 141 when the carriage 120 returns in the Y2 direction. This completely cures the white ink. The white ink is leveled because it receives light after a certain amount of time has passed since it landed. As a result, the gaps between ink dots of white ink are reduced, and the concealability per layer of white ink is improved. However, since the thickness of one white ink layer is reduced by leveling, the masking layer 40 is formed by laminating a plurality of white ink layers.

However, the method of forming the concealing layer 40 is not limited as long as the desired concealing property is obtained. The concealing layer 40 may be formed of one layer of white ink if possible. Also, the white ink of the concealing layer 40 may be cured immediately after landing on the adhesive layer 30 .

In subsequent steps S05 and S06, the image layer 50 is formed on the adhesive layer 30 and the masking layer 40. FIG. In steps S<b>05 and S<b>06 , the printer 100 ejects photocurable process color ink and irradiates the process color ink with light to completely cure the ink, thereby forming the image layer 50 on the masking layer 40 . Specifically, in step S<b>05 , process color ink is ejected onto the masking layer 40 by the printer 100 . In step S<b>06 , the process color ink ejected onto the masking layer 40 is completely cured to form the image layer 50 . FIG. 5 is a schematic diagram of the steps of forming the image layer 50 (steps S05 and S06). Steps S05 and S06 are the same as steps S01 and S02 except that the ejected ink is process color ink and the color image specified by the manufacturer of image transfer sheet 10 is formed with process color ink.

In subsequent steps S07 and S08, an overcoat layer 60 is formed on the image layer 50. FIG. In steps S<b>07 and S<b>08 , the printer 100 ejects photocurable transparent ink and irradiates the transparent ink with light to completely cure the ink, thereby forming the overcoat layer 60 on the image layer 50 . Specifically, in step S<b>07 , the printer 100 ejects transparent ink onto the image layer 50 . In step S<b>08 , the transparent ink ejected onto the image layer 50 is completely cured to form the overcoat layer 60 . FIG. 6 is a schematic diagram of the step of forming the overcoat layer 60 (steps S07 and S08). Steps S 07 and S 08 are similar to steps S 03 and S 04 , except that the ink that is ejected is transparent ink and that overcoat layer 60 does not have to be as thick as concealing layer 40 . The transparent ink is leveled because it receives light after a certain period of time has passed since it landed on the image layer 50 . As a result, the surface of the overcoat layer 60 is smoothed, and the overcoat layer 60 has a glossy finish. As a result, the glossiness of the image transfer sheet 10 is improved. However, as described above, the overcoat layer 60 may be formed in a matte tone with no gloss, or may have a texture pattern aiming at a design effect. Also, the thickness of the overcoat layer 60 is not particularly limited, and may be the same as or thicker than the concealing layer 40 .

In step S<b>09 , an application sheet 70 is attached as a protective sheet onto the overcoat layer 60 . The adhesive layer 71 of the application sheet 70 is attached to the overcoat layer 60 . Thus, the image transfer sheet 10 is completed. The transferred image on the image transfer sheet 10 thus formed is a color image designated by the manufacturer (however, if the designated image is a black-and-white image, it is a black-and-white image). Further, the image transfer sheet 10 has a configuration that does not have a border around the transferred image. However, it is also possible, for example, to create a border around the transferred image by the obscuring layer 40 .

[Image transfer method]
Next, a procedure for transferring an image using the image transfer sheet 10 will be described. Although illustration is omitted, when a plurality of transfer images to be transferred to a plurality of locations are formed on a single image transfer sheet 10, the image transfer sheet 10 is each transferred to a single sheet prior to transfer. It may be cut into multiple portions containing the transferred image. FIG. 7 is a flow chart showing the procedure of image transfer using the image transfer sheet 10. As shown in FIG. As shown in FIG. 7, when transferring an image using the image transfer sheet 10, first, in step S11, the upper surface of the application sheet 70 is rubbed with a plate-like squeegee 200 (see FIG. 9). Thereby, the adhesive layer 30, the masking layer 40, the image layer 50, and the overcoat layer 60 are brought into closer contact. However, this work may be performed when the image transfer sheet 10 is produced (after step S09). Further, what rubs the upper surface of the application sheet 70 is not limited to the plate-shaped squeegee 200, and may be, for example, a user's hand or a baren. Step S11 may be omitted if not particularly necessary.

As shown in FIG. 7, the release paper 20 is peeled off from the adhesive layer 30 in the following step S12. FIG. 8 is a schematic diagram of step S12. As shown in FIG. 8, in step S12, the release paper 20 is peeled off, but the application sheet 70 remains on the image transfer sheet 10 without being peeled off.

In step S13, the adhesive layer 30 from which the release paper 20 has been peeled off is brought into contact with the material 5 to be transferred. In the following step S<b>14 , the application sheet 70 is pressed toward the adhesive layer 30 while the adhesive layer 30 is in contact with the transferred material 5 . FIG. 9 is a schematic diagram of step S14. As shown in FIG. 9, in step S14, the application sheet 70 is pressed toward the adhesive layer 30 by rubbing the upper surface of the application sheet 70 with the squeegee 200, for example. As a result, the adhesive layer 30 is in close contact with the material to be transferred 5 and adhered to the material to be transferred 5 . In step S14, the adhesive layer 30 may be brought into close contact with the material 5 to be transferred. Therefore, in step S14, the application sheet 70 may simply be pressed toward the transfer-receiving material 5 without being rubbed.

As shown in FIG. 7, in step S15 after step S14, the application sheet 70 is peeled off from the overcoat layer 60. As shown in FIG. FIG. 10 is a schematic diagram of step S15. Thus, the transfer of the image printed on the image transfer sheet 10 to the transferred material 5 is completed.

[Action and effect of the first embodiment]
As described above, the image transfer sheet 10 according to this embodiment includes the release paper 20, the application sheet 70 having the adhesive layer 71, and the layer in which the photocurable process color ink is completely cured. and an image layer 50 provided between the application sheet 70 and the application sheet 70 . The image transfer sheet 10 further comprises an overcoat layer 60 provided between the application sheet 70 and the image layer 50, and an adhesive layer 30 provided between the release paper 20 and the image layer 50. . The overcoat layer 60 is a layer obtained by completely curing photocurable transparent ink, and is adhered to the adhesive layer 71 of the application sheet 70 . The adhesive layer 30 is a layer in which photocurable white ink is semi-cured, and has adhesiveness to the material to be transferred 5 . In making such an image transfer sheet 10, the step of cutting around the image is not required. Therefore, the image transfer sheet 10 according to this embodiment can be manufactured easily and quickly. Further, such an image transfer sheet 10 can be manufactured using general-purpose release paper 20 and ink, instead of the special material described in Patent Document 1.

Further, the image transfer sheet 10 according to this embodiment includes an opaque concealing layer 40 which is a layer in which white ink is completely cured and which is provided between the adhesive layer 30 and the image layer 50 . Therefore, the image layer 50 formed on the masking layer 40 can be clearly colored regardless of the color of the material 5 to be transferred. In this embodiment, the adhesive layer 30 is also formed of white ink, but if the adhesive layer 30 is made thick, problems may occur in the transfer process. ing. Specifically, when the semi-cured adhesive layer 30 is thickened, the adhesive layer 30 tends to protrude outside the image transfer sheet 10 when the image transfer sheet 10 is rubbed in the transfer process. In addition, if the semi-cured adhesive layer 30 is thickened, the image layer may not be formed on the transferred material 5 when the image transfer sheet 10 is rubbed in the transfer process or when a force is applied to the image transfer sheet 10 after the transfer process is completed. 50 and overcoat layer 60 tend to move out of alignment. Therefore, in this embodiment, the adhesive layer 30 is made thinner and the concealing layer 40 is made thicker than the adhesive layer 30 .

In this embodiment, the ink forming the concealing layer 40 is white ink, but other opaque special color ink may be used. For example, when the image transfer sheet 10 is desired to have a metallic finish, the ink forming the concealing layer 40 may be metallic ink. In addition, in the present embodiment, the adhesive layer 30 is also formed of white ink in order to further enhance the concealability. good. Furthermore, the process color inks forming the image layer 50 are not limited to photocurable inks. The process color inks forming the image layer 50 may be thermosetting inks, for example.

The image transfer sheet 10 according to this embodiment further includes an overcoat layer 60 in which transparent ink is completely cured on the image layer 50 . With such a configuration, the image layer 50 is protected by the overcoat layer 60, so the durability of the image transfer sheet 10 is improved. Furthermore, the image transfer sheet 10 according to this embodiment further includes an application sheet 70 attached on the overcoat layer 60 . With such a configuration, the application sheet 70 can protect the image transfer sheet 10 before transfer, and the image transfer sheet 10 can be easily stored and carried. In this embodiment, the application sheet 70 is rubbed while the adhesive layer 30 is in contact with the transfer material 5, so that the adhesive layer 30 is brought into close contact with the transfer material 5, as shown in step S14 of FIG. Therefore, there is a possibility that the application sheet 70 is scratched by the operation of rubbing the application sheet 70 . However, the application sheet 70 is peeled off in step S15 after step S14. Therefore, the image transfer sheet 10 can be adhered to the transferred material 5 without damaging or soiling the image transfer sheet 10 .

[Second embodiment]
In a second embodiment, the image transfer sheet has another aspect of the adhesive layer and does not have the concealing layer. Other configurations of the image transfer sheet according to the second embodiment are common to those of the first embodiment. In the following description of the second embodiment, the same reference numerals as those of the first embodiment are used for members having functions common to those of the first embodiment, and overlapping descriptions are omitted or simplified.

[Structure of image transfer sheet]
FIG. 11 is a schematic cross-sectional view of the image transfer sheet 11 according to the second embodiment. As shown in FIG. 11, the image transfer sheet 11 according to the present embodiment includes a release paper 20, an adhesive layer 31 formed on the release paper 20, an image layer 50 formed on the adhesive layer 31, and an image. It comprises an overcoat layer 60 formed on the layer 50 and an application sheet 70 applied on the overcoat layer 60 .

The release paper 20 may be the same as in the first embodiment, or may be different. The release paper 20 is preferably an easily available one such as a general sticker mount, but is not limited thereto. In this embodiment, the adhesive layer 31 is made of photocurable transparent ink. The adhesive layer 31 is a layer obtained by semi-curing photocurable transparent ink on the release paper 20 and has adhesiveness to the transferred material 5 . The adhesive layer 31 is a transparent layer. The adhesive layer 31 is formed on the release paper 20 by an inkjet printer 100 as shown in FIG. 3, for example.

The adhesive layer 31 is again configured conformally to the image layer 50 . As a result, a borderless transferred image can be obtained as in the first embodiment. The thickness of the adhesive layer 31 may be approximately the same as the preferred thickness of the adhesive layer 30 according to the first embodiment. However, the thickness of the adhesive layer 31 is not particularly limited.

The image layer 50 is a layer in which the process color ink is completely cured on the adhesive layer 31 . The overcoat layer 60 is a layer in which clear ink is completely cured on the image layer 50 . The image layer 50 and overcoat layer 60 are here the same as in the first embodiment. However, the image layer 50 may be a layer in which the process color ink is completely cured on the adhesive layer 31, and the ink used and its thickness are not particularly limited. The overcoat layer 60 may be a layer in which transparent ink is completely cured on the image layer 50, and the ink used and its thickness are not limited. The application sheet 70 is also not particularly limited as long as it has an adhesive layer 71 and functions as a protective sheet.

[Method for producing image transfer sheet]
A method for producing the image transfer sheet 11 according to the second embodiment will be described below. FIG. 12 is a flow chart showing the procedure for producing the image transfer sheet 11 according to the second embodiment. As shown in FIG. 12, in the production of the image transfer sheet 11 according to the present embodiment, first, in step S21, photocurable transparent ink is ejected onto the release paper 20 by the printer 100. As shown in FIG. In the subsequent step S22, the transparent ink ejected onto the release paper 20 is irradiated with light to semi-harden the transparent ink, thereby forming the adhesive layer 31 having adhesiveness. The transparent ink of the adhesive layer 31 may be semi-cured immediately after landing on the release paper 20, or may be semi-cured after being leveled after landing. The adhesive layer 31 may be formed from one transparent ink layer, or may be formed by laminating a plurality of transparent ink layers.

In the following step S23, process color ink is discharged onto the adhesive layer 31 by the printer 100. FIG. In step S<b>24 , the process color ink ejected onto the adhesive layer 31 is completely cured to form the image layer 50 .

In step S25, the printer 100 ejects transparent ink onto the image layer 50. FIG. In step S<b>26 , the transparent ink ejected onto the image layer 50 is completely cured to form the overcoat layer 60 . The overcoat layer 60 may be formed in a gloss tone, but may be formed in a matte tone if necessary. In addition, the overcoat layer 60 may have a texture pattern aiming at a design effect. In step S<b>27 , an application sheet 70 is applied as a protective sheet onto the overcoat layer 60 . The image transfer sheet 11 according to the second embodiment is thus completed.

The method of image transfer using the image transfer sheet 11 according to the second embodiment is the same as that of the first embodiment, so the description is omitted. FIG. 13 is a schematic cross-sectional view of the image transfer sheet 11 after image transfer to the transfer material 5 is completed. As shown in FIG. 13, the adhesive layer 31 of the image transfer sheet 11 is adhered to the transferred material 5 after the image transfer is completed. An image layer 50 is formed on the adhesive layer 31 and an overcoat layer 60 is formed on the image layer 50 . Finally, the release paper 20 and the application sheet 70 are removed.

[Action and effect of the second embodiment]
As described above, the image transfer sheet 11 according to the present embodiment includes the release paper 20, the adhesive layer 31 which is a layer in which the photocurable transparent ink is semi-cured on the release paper 20 and has adhesiveness, An image layer 50 in which the process color ink is completely cured on the adhesive layer 31, an overcoat layer 60 in which the transparent ink is completely cured on the image layer 50, an application sheet 70 attached on the overcoat layer 60, It has Such an image transfer sheet 11 can also be manufactured easily and quickly without using a special material, like the image transfer sheet 10 according to the first embodiment. In the image transfer sheet 11 according to this embodiment, the adhesive layer 31 is transparent, and the image layer 50 is formed on the transparent adhesive layer 31 . Since the image transfer sheet 11 according to the second embodiment has fewer printed layers than the image transfer sheet 10 according to the first embodiment, it can be manufactured more easily and quickly than the image transfer sheet 10 according to the first embodiment. be able to. The image transfer sheet 11 according to the present embodiment is used when the influence of the color of the transfer material 5 is not a particular problem, or when the color of the transfer material 5 is desired to be seen through for a more natural finish. can be preferably used. For example, when the material to be transferred 5 is white, the color development of the image transfer sheet 11 according to the second embodiment is substantially the same as that of the image transfer sheet 10 according to the first embodiment.

The ink forming the adhesive layer 31 may not be transparent photocurable ink, and may be, for example, opaque photocurable ink. The ink forming the adhesive layer 31 may be, for example, photocurable white ink.

[Other embodiments]
Several preferred embodiments of the present invention have been described above. However, the above-described embodiments are merely examples, and the present invention can be embodied in various other forms.

For example, in the above-described embodiments, the image transfer sheet has an overcoat layer on the image layer and a protective sheet attached to the overcoat layer. It doesn't have to be. When the image transfer sheet is provided with a protective sheet, the protective sheet may be attached directly onto the image layer or via another layer. The layer interposed between the image layer and the protective sheet is not limited to an overcoat layer made of transparent ink. It may be an overcoat layer.

In the above-described embodiment, the image transfer sheets 10 and 11 were produced by the flatbed type printer 100, in which the flatbed 110 on which the object to be printed is placed, moves. It may be produced by a roll-to-roll type printer that prints while feeding the recording medium. In that case, the recording medium mounted on the roll-to-roll type printer may be a roll of release paper.

Otherwise, the embodiments do not limit the invention unless specifically stated.

5 Material to be Transferred 10 Image Transfer Sheet (First Embodiment)
11 Image Transfer Sheet (Second Embodiment)
20 release paper 30 adhesive layer (first embodiment)
31 adhesive layer (second embodiment)
40 hiding layer 50 image layer 60 overcoat layer 70 application sheet (protective sheet)
100 inkjet printer

Claims (7)

a release paper;
a protective sheet having an adhesive layer;
an image layer provided between the release paper and the protective sheet, which is a layer in which a photocurable process color ink is completely cured;
an overcoat layer, which is a layer in which photocurable transparent ink is completely cured, is provided between the protective sheet and the image layer, and is attached to the adhesive layer of the protective sheet;
An adhesive layer, which is a layer in which a photocurable ink is semi-cured, has adhesiveness to a transferred material, and is provided between the release paper and the image layer,
Image transfer sheet. The ink semi-cured on the adhesive layer is an opaque ink,
an opaque concealing layer provided between the adhesive layer and the image layer, wherein the opaque ink is fully cured;
The image transfer sheet according to claim 1. The thickness of the concealing layer is thicker than the thickness of the adhesive layer,
The image transfer sheet according to claim 2. The ink semi-cured on the adhesive layer is a transparent ink,
The image transfer sheet according to claim 1. A step of ejecting a photocurable ink with an inkjet printer and irradiating the ink with light to semi-harden the ink to form an adhesive layer having adhesiveness to a transferred material on a release paper;
a step of ejecting a photocurable process color ink with an inkjet printer and irradiating the process color ink with light to completely cure the ink, thereby forming an image layer above the adhesive layer;
a step of ejecting a photocurable transparent ink with an inkjet printer and irradiating the transparent ink with light to completely cure the transparent ink to form an overcoat layer above the image layer;
a step of attaching the adhesive layer of a protective sheet having an adhesive layer to the overcoat layer;
peeling the release paper from the adhesive layer;
a step of contacting the adhesive layer after the release paper has been peeled off with an object to be transferred;
pressing the protective sheet toward the adhesive layer while the adhesive layer is in contact with the material to be transferred;
peeling the protective sheet from the overcoat layer;
An image transfer method, comprising: The ink semi-cured on the adhesive layer is an opaque ink,
After the step of forming the adhesive layer and before the step of forming the image layer, the opaque ink is discharged by an inkjet printer, and the opaque ink is irradiated with light to be completely cured, thereby forming an opaque ink. further comprising forming a concealing layer on the adhesive layer;
6. The image transfer method according to claim 5. The ink semi-cured on the adhesive layer is a transparent ink,
6. The image transfer method according to claim 5.

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