JP2005292304A - Image forming method including optical diffraction structure and recorded matter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming method or the like in which a light diffraction structure can be provided on a portion formed in advance by a thermal transfer method.
SOLUTION: A visible heat transfer sheet 23 in which a transfer layer 27 including a release layer 25 containing no release agent is laminated on a base sheet 24 is opposed to a transfer target 100, and the transfer layer 27 is placed on the surface thereof. Heat transfer to the transfer target 100 so that the release layer 25 remains on the surface, and light diffraction structures 51 a and 51 b provided on the light diffraction structure transfer sheet 50 on the release layer 25 left on the surface of the transfer layer 27. Transferring the light diffraction structure layer 51 including
[Selection] Figure 8

Description

  The present invention relates to a method for forming an image including a light diffractive structure and a recorded matter having an image including a light diffractive structure.

  A method for forming an image including print information and a light diffraction structure is widely known as a countermeasure against information falsification. For example, a method is known in which predetermined information is first printed on a transfer object, and a layer provided with the light diffraction structure of the light diffraction structure transfer sheet is transferred onto the transfer information (for example, a patent) Reference 1).

JP-A-8-118857

  However, the above-described method has a problem that when the information printed on the transfer medium is printed by the thermal transfer method, the light diffraction structure does not adhere to the printed portion and is difficult to transfer.

  Therefore, an object of the present invention is to provide an image forming method or the like in which a light diffraction structure can be provided on a portion that has been previously formed by a thermal transfer method.

  The present invention solves the above-described problems by the following method. In order to facilitate understanding of the present invention, reference numerals in the accompanying drawings are appended in parentheses, but the present invention is not limited to the illustrated embodiment.

  According to the method for forming an image having a light diffraction structure of the present invention, a thermal transfer sheet in which a transfer layer (27) including a release layer (25) containing no release agent is laminated on a base sheet (24). (23) facing the transfer body (100), and thermally transferring the transfer layer to the transfer body so that the release layer remains on the surface, and the transfer layer remaining on the surface of the transfer layer And transferring the light diffractive structure layer (51) including the light diffractive structures (51a, 51b) provided on the light diffractive structure transfer sheet (50) onto the release layer. To do.

  The inventor paid attention to the fact that the light diffraction structure does not adhere to the portion printed by thermal transfer because the surface of the portion contains a release agent. According to the present invention, the base sheet side and the transfer layer are separated by the release layer in the thermal transfer sheet, and the transfer layer has a release layer that is substantially free of a release agent such as wax, silicone, and surfactant. Since it is thermally transferred to the transfer target so as to remain on the surface, the outermost surface of the transfer layer on the transfer target is a release layer containing no release agent. Therefore, the light diffractive structure layer can be adhered to the release layer, and the light diffractive structure layer can be further transferred onto the transfer layer thermally transferred onto the transfer target.

  The “peeling layer” is a generic name for layers that are included in the transfer layer and that are in a position where the transfer layer is separated from the base sheet side during thermal transfer. Therefore, a layer having not only a separation function but also other functions may be used. “To leave the release layer” means that the release layer in the thermal transfer sheet is included in the transfer layer as it is and separated from the substrate sheet side and transferred to the transfer target. And the case of separating from the base sheet side from the middle of the release layer in a state of remaining on the sheet side.

  The “transfer layer” includes the case of only the release layer and the case where other layers are laminated in addition to the release layer. The “light diffractive structure” includes a diffraction grating that is simply a repetition of a concavo-convex pattern and a so-called hologram on which interference fringes expressing a predetermined shape are formed.

  In the transfer layer, an ink layer (26) containing ink is further laminated on the release layer, and in the thermal transfer step, the transfer layer forms a specific shape (21) on the transfer target. Thus, thermal transfer may be performed. Thereby, it is possible to give a special meaning to a specific shape formed by the transfer layer on the transfer target, and the shape can be used as information. In particular, if the ink is visible under visible light, the user can visually recognize the specific shape. Since the shape is formed by a thermal transfer method, the shape can be easily changed as necessary. The “specific shape” may be any shape that can be visually recognized, and includes symbols, characters, patterns, and the like.

  In the step of transferring the light diffraction structure layer, the light diffraction structure may be transferred to a part of the transfer layer transferred onto the transfer target. Accordingly, since the transfer layer transferred onto the transfer target is not entirely covered, the transferred transfer layer can be visually recognized even when the transfer layer is not transparent.

  The present invention also provides a recorded matter (A) having an image including a thermal transfer portion (21) formed by thermal transfer and a light diffraction structure (51b) laminated thereon, The surface in contact with the light diffraction structure may be embodied as a recorded material (A) containing no release agent.

  As described above, according to the present invention, by using a thermal transfer sheet in which a transfer layer including a release layer that does not contain a release agent is laminated on a base sheet, a transfer target is first transferred by a thermal transfer method. Even in a portion formed on the body, a light diffraction structure can be provided on the portion.

  FIG. 1 shows a recorded matter A having a final image 1 having a light diffraction structure finally obtained by the image forming method in the present embodiment. The form of the recorded matter A may be any type such as a seal, a card, and a bill. In the recorded matter A in this embodiment, the final image 1 is provided on the entire surface of the transfer target, and further on both sides.

  The final image 1 includes a hologram transfer unit 10, a first diffraction grating transfer unit 20, a second diffraction grating transfer unit 30, and a third diffraction grating transfer unit 40. The hologram transfer unit 10 is provided with a computer generated hologram having the shape “A”. The first diffraction grating transfer unit 20 includes a thermal transfer information unit 21 on which characters are printed by thermal transfer, a horizontal stripe transfer unit 22a in which the diffraction grating is transferred in horizontal stripes, and a character transfer unit 22b in which characters are transferred. The second diffraction grating transfer unit 30 includes a transfer unit 31 to which the diffraction grating is transferred and a non-transfer unit 32 that is a part where the diffraction grating is not transferred in a letter shape. Similarly to the second diffraction grating transfer unit 30, the third diffraction grating transfer unit 40 includes a transfer unit 41 and a non-transfer unit 42. Since the configuration and formation method of the third diffraction grating transfer unit 40 are the same as those of the second diffraction grating transfer unit 30, the description of the third diffraction grating transfer unit 30 is omitted.

  In this embodiment, the final image 1 is formed by heating each thermal transfer sheet shown in FIGS. 2A to 2C with a thermal head of a thermal transfer printer as described later. Hereinafter, in the description of the present embodiment, a sheet on which a hologram can be further transferred onto a pattern printed by thermal transfer is exemplified as a visible transfer sheet, and a sheet that cannot be transferred is referred to as an invisible sheet, but may be visible or invisible anywhere. In the thermal transfer sheet 23 shown in FIG. 2A, a transfer layer 27 is laminated on a base sheet 24, and the transfer layer 27 includes a release layer 25 and a visible ink layer 26. The thermal transfer sheet 23 is used to form the thermal transfer information part 21. The release layer 25 and the base sheet 24 are separated, and the transfer layer 27 is thermally transferred to the transfer target. The visible ink layer 26 is made of ink that can be visually recognized with visible light. The release layer 25 is provided in order to enhance the peelability of the base sheet 24 and the visible ink layer 26, but does not contain a release agent. For this reason, the visible ink layer 26 has sufficient adhesiveness to the transfer target. Hereinafter, this thermal transfer sheet 23 is referred to as a visible transfer sheet 23.

  In the thermal transfer sheet 33 shown in FIG. 2B, a transfer layer 37 is laminated on a base sheet 34, and the transfer layer 37 includes a release layer 35 and an invisible ink layer 36. The thermal transfer sheet 33 is used to form the non-transfer portions 32 and 42. The invisible ink layer 36 is made of so-called stealth ink that cannot be seen with visible light. The release layer 35 is transparent under visible light and contains a release agent. Hereinafter, this thermal transfer sheet 33 is referred to as an invisible transfer sheet 33.

  A thermal transfer sheet 50 shown in FIG. 2C is used to form the hologram transfer unit 10, the horizontal stripe transfer unit 22a, the character transfer unit 22b, and the transfer units 31 and 41, and includes a hologram layer 51 as a light diffraction structure layer, A release layer 52 and a base sheet 53 are sequentially laminated. Hereinafter, this thermal transfer sheet 50 is referred to as a light diffraction structure transfer sheet 50.

  As shown in FIG. 3, the hologram layer 51 is provided with hologram portions 51a including a letter “A” formed by a computer generated hologram at regular intervals, and a diffraction grating portion 51b composed of a diffraction grating on the entire surface thereof. Is provided. The hologram portion 51a is thermally transferred to form the hologram transfer portion 10, and the diffraction grating portion 51b is thermally transferred to form the horizontal stripe transfer portion 22a, the character transfer portion 22b, and the transfer portions 31 and 41. A range indicated by a dotted line 51 c indicates the size of the final image 1. The dotted line 51c is shown for explanation, and it is not necessary to actually apply it to the hologram layer 51.

  The interference fringes of the hologram part 51a and the diffraction grating part 51b provided on the hologram layer 51 are recorded as reliefs having a concavo-convex pattern on the surface, recorded three-dimensionally in the thickness direction, or of transmittance Any of those recorded so that diffraction is caused by a change in the amplitude of light due to the change may be used. Specifically, there are laser reproduction holograms such as Fresnel holograms and image holograms, white light reproduction holograms such as Lippmann holograms and rainbow holograms, holographic stereograms utilizing these principles, color holograms, and the like.

  These holograms may be manufactured by a conventionally known method so as to form the hologram layer 51 shown in FIG. It should be noted that the material constituting the hologram layer 51 is printed in a size (dot), a shaded dot pattern, or a combination thereof so that the underlying information is not completely concealed when transferred to the transfer object. By doing so, the information is not completely concealed, so it does not have to be transparent.

  The release layer 52 is provided to improve the peelability between the hologram layer 51 and the base sheet 53. What is necessary is just to determine the material to comprise suitably according to the base material sheet 53. FIG. The base material sheets 24, 34, 53 of the thermal transfer sheets 23, 33, 50 described above need only have a certain degree of rigidity and heat resistance. The total thickness of each of the thermal transfer sheets 23, 33, 50 may be a thickness that does not hinder thermal conduction from the thermal head.

  Hereinafter, a method of forming the final image 1 using the thermal transfer sheets 23, 33, and 50 described above will be described in order. First, the thermal transfer information part 21 indicated by date information “2004/12/30” as a specific shape as shown in FIG. 4A is formed on the transfer target 100 using the visible transfer sheet 23. To do. The visible transfer sheet 23 is opposed to the surface of the transfer target 100 so that the visible ink layer 26 of the visible transfer sheet 23 and the transfer target 100 are overlapped, and a thermal head is applied from the substrate sheet 24 side, and the date information The heating position is moved so that is formed on the transfer target 100. What is necessary is just to determine the to-be-transferred material 100 suitably according to the recorded matter finally obtained.

  Thereby, the peeling layer 25 and the visible ink layer 26 as the transfer layer 27 are separated from the base sheet 24 and transferred to the surface of the transfer target 100 so as to form date information. Since the visible transfer sheet 23 is separated from the release layer 25 when heated, as shown in FIG. 4B, the release layer 25 that does not contain a release agent is formed on the outermost surface on the transfer target material 100 as a transfer destination. Become. The thermal transfer information part 21 is formed by the above method.

  Next, by using the invisible transfer sheet 33 on the transfer target 100, the non-transfer portion 32 indicated by the character information “DNP” shown in FIG. 5A is formed. The invisible transfer sheet 33 is opposed to the transfer target 100 so that the invisible ink layer 36 of the invisible transfer sheet 33 and the surface of the transfer target 100 overlap each other. A thermal head is applied from the substrate sheet 34 side, and the heating position is moved so that the character information is formed on the transfer target 100. As a result, the peeling layer 35 and the invisible ink layer 36 as the transfer layer 37 are peeled off from the substrate sheet 34 and transferred to the transfer target 100 so as to form character information.

  Since the transfer layer 37 is separated from the release layer 35 when the invisible transfer sheet 33 is heated, the release layer 35 containing a release agent is formed on the transfer destination transfer material 100 as shown in FIG. It becomes the outermost surface. The non-transfer portion 32 is formed by the above method. Although the character information “DNP” of the non-transfer portion 32 in FIG. 5A is shown in a visible state for convenience of explanation, the release layer 35 is transparent and the invisible ink layer is made of stealth ink. In fact, it is not visible under visible light. The non-transfer portion 42 is also formed by the same method as the non-transfer portion 32.

  Next, the hologram transfer unit 10, the horizontal stripe transfer unit 22 a, the character transfer is performed by using the light diffraction structure transfer sheet 50 for the transfer target 100 on which the thermal transfer information unit 21 and the non-transfer units 32 and 42 are formed. The part 22b and the transfer parts 31 and 41 are formed. The hologram layer 51 of the light diffraction structure transfer sheet 50 is overlaid on the surface of the transfer target 100. The position of the light diffraction structure transfer sheet 50 is set so that the position of the hologram part 51a to be transferred is the position where the hologram transfer part 10 is to be formed on the transfer target 100.

  By positioning the light diffraction structure transfer sheet 50 in this way, the range indicated by the dotted line 51 c of the light diffraction structure transfer sheet 50 matches the range of the final image 1 to be formed on the transfer target 100. Accordingly, the diffraction grating portion 51b of the optical diffraction structure transfer sheet 50 overlaps the range where the horizontal stripe transfer portion 22a, the character transfer portion 22b, and the transfer portions 31 and 41 of the transfer target 100 are to be formed. A thermal head is applied from the substrate sheet 53 side, and the heating position is moved so that the hologram portion 51a is transferred. FIG. 6 shows the transfer target 100 onto which the hologram portion 51a has been transferred.

  Subsequently, a horizontal stripe transfer portion 22a and a character transfer portion 22b are formed. As described above, since the diffraction grating portion 51b of the light diffraction structure transfer sheet 50 overlaps the range where the horizontal stripe transfer portion 22a and the character transfer portion 22b of the transfer target 100 are to be formed, the light diffraction structure transfer sheet. The position 50 need not be moved. In the range where the horizontal stripe transfer portion 22a is to be formed, the heating position of the thermal head is moved so that the diffraction grating of the diffraction grating portion 51b is transferred in a horizontal stripe shape, and in the range where the character transfer portion 22b is to be formed, The diffraction grating is moved so as to form character information “HOLO”. FIG. 7 shows a state in which the horizontal stripe transfer portion 22a and the character transfer portion 22b are formed on the transfer target 100.

  As described above, in the thermal transfer information part 21, since the release layer 25 on the outermost surface does not contain a release agent, the transferred diffraction grating part 51b becomes the release layer of the thermal transfer information part 21, as shown in FIG. 25 is transferred onto 25. Accordingly, the diffraction grating portion 51 b is also formed in a horizontal stripe shape on the thermal transfer information portion 21 already formed on the transfer target 100. Thus, the first diffraction grating transfer unit 20 is formed. Since the diffraction grating portion 51b is formed in a horizontal stripe shape on the thermal transfer information portion 21, the diffraction grating portion 51b is not transparent but does not cover the entire thermal transfer information portion 21.

  Subsequently, the transfer part 31 is formed. For the same reason as the horizontal stripe transfer portion 22a and the character transfer portion 22b, the position of the light diffraction structure transfer sheet 50 does not have to be moved. The heating position of the thermal head is moved so that the diffraction grating of the diffraction grating part 51b is transferred to the range where the transfer part 31 is to be formed. At this time, the transfer to the non-transfer portion 32 may not be avoided. This is because, in the non-transfer portion 32, since the release agent is included in the release layer 35 on the outermost surface as described above, the diffraction grating is not transferred onto the non-transfer portion 32.

  As a result, as shown in FIG. 9, the diffraction grating portion 51b is transferred in a state where the non-transfer portion 32 is avoided. Accordingly, the diffraction grating portion 51 b is not transferred to the character information “DNP” portion that is the transferred portion 32. As described above, since the character information “DNP” of the non-transfer portion 32 is transparent, the character portion “DNP” is in a state where there is no gap under visible light. Thereby, the second diffraction grating transfer part 30 is formed. The method of forming the third diffraction grating transfer unit 40 is the same as the method of forming the second diffraction grating transfer unit 30 described above. The final image 1 can be formed on the transfer target 100 by the above procedure. After printing on the entire surface of the transfer target 100 with the visible transfer sheet 23, printing is performed in this order or in the reverse order on the invisible transfer sheet 33 or the light diffraction structure transfer sheet 50 in the normal three-color printing process. The final image 1 may be formed on the transfer target 100.

  The present invention is not limited to the above-described form and may be implemented in various forms. For example, in this embodiment, the final image 1 is formed on the entire recorded matter A, but may be a part of the recorded matter A. Further, the heating method for thermal transfer is not limited to the thermal head, and any heating method can be used as long as dot transfer is possible. For example, laser light may be used. In that case, it is necessary to provide each thermal transfer sheet with a layer having a photothermal conversion function. In this embodiment, all the transfer is performed by the thermal transfer method. However, the images 22a, 22b, 31, and 41 relating to the non-transfer portions 32 and 42 and the light diffraction structure may not be formed by the thermal transfer method.

  Each of the thermal transfer sheets 23, 33, and 50 is provided with a layer that increases the thermal head sliding property on the side on which the thermal head hits when the base sheet 24, 34, 53 is not sufficiently slippery and a so-called sticking phenomenon occurs. May be. In addition to the above-described layers, layers may be further stacked as long as the present invention can be implemented. For example, a layer having high adhesiveness with the visible ink layer 26 may be provided on the surface of the transfer target 100 onto which the visible transfer sheet 23 is transferred.

  The character transfer unit 22b is not limited to character information, and may have a predetermined shape such as a symbol or a pattern. Further, the number of places where the diffraction grating 51b is transferred to form a predetermined shape is not limited to one. In addition to the thermal transfer information section 21, variable information can be increased, and the purpose of use is expanded and the security is enhanced. Further, the patterns and characters shown on the hologram transfer unit 10, the first diffraction grating transfer unit 20, the second diffraction grating transfer unit 30, and the third diffraction grating transfer unit 40 are not limited to the above-described modes.

  In addition, the second diffraction grating transfer unit 30 and the third diffraction grating transfer unit 40 may be formed by transferring the diffraction grating part 51 b first so as to avoid the shapes of the non-transfer parts 32 and 42. In this case, since a gap is formed in the shape of the non-transfer portions 32 and 42, stealth ink may be put into the gap. When the stealth ink is added later, the release agent may not be included on the outermost surfaces of the non-transfer portions 32 and 42. Of course, you may print using normal visible ink instead of stealth ink.

The figure which shows the last image given to the recorded matter formed in this form. (A)-(c) is sectional drawing of the thermal transfer sheet used in order to obtain the final image shown in FIG. The figure which shows the hologram layer of the optical diffraction structure transfer sheet shown in FIG.2 (c). (A) is a figure which shows the to-be-transferred body in which the thermal transfer information part was formed, (b) is a figure which shows sectional drawing of the thermal transfer information part formed on the to-be-transferred body. (A) is a figure which shows the to-be-transferred body in which the thermal transfer information part and the non-transfer part were formed, (b) is a figure which shows sectional drawing of the non-transfer part formed on the to-be-transferred body. The figure which shows the to-be-transferred body in which the hologram part was formed. The figure which shows the to-be-transferred body in which the 2nd diffraction grating transcription | transfer part was formed. Sectional drawing which shows the state by which the diffraction grating was transcribe | transferred on the thermal transfer information part. Sectional drawing which shows the state by which the diffraction grating was transcribe | transferred on to-be-transferred so that a non-transfer part may be avoided.

Explanation of symbols

1 Final Image 23 Thermal Transfer Sheet 25 Release Layer 27 Transfer Layer 50 Light Diffraction Structure Transfer Sheet 51 Light Diffraction Structure Layer 100 Transferred Material A Recorded Material

Claims (4)

The transfer layer including a release layer that does not contain a release agent is opposed to a transfer target body, and the transfer layer is left on the surface of the transfer layer so that the release layer remains on the surface. A process of thermal transfer to a transfer target;
A step of transferring a light diffraction structure layer including a light diffraction structure provided on a light diffraction structure transfer sheet onto the release layer left on the surface of the transfer layer;
A method for forming an image having a light diffraction structure, comprising:   In the transfer layer, an ink layer containing ink is further laminated on the release layer, and in the thermal transfer step, the transfer layer is thermally transferred so as to form a specific shape on the transfer target. The image forming method according to claim 1.   3. The image forming method according to claim 1, wherein in the step of transferring the light diffraction structure layer, the light diffraction structure is transferred to a part of the transfer layer transferred onto the transfer target. . A recorded matter having an image including a thermal transfer portion formed by thermal transfer and a light diffractive structure laminated thereon, and a release agent contains on the surface of the thermal transfer portion that is in contact with the light diffractive structure Recorded matter characterized by not being made.

Images