当前申请(专利权)人地址：
11-37, Yuhigaoka 2-chome,Toyonaka-shi Osaka 561-0864,JP
摘要：
In order to enable a natural and clear image to appear in both light reflection and light transmission usage modes of a light-reflection/light-transmission image sheet having front and back-side images (3, 4) overlying each other with a sheet-like base material (2) that is reflective and transmissive interposed therebetween, the density distribution of the back-side image (4) of the light-reflection/light-transmission image sheet is obtained by reducing a high-density portion (N1) that exceeds a set density α in the density distribution of the front-side image (3), to the set density α or a density close in value thereto.
技术问题语段：
The technical problem addressed in this patent is to provide a light-reflection/light-transmission image sheet that can produce a clear and natural image in both the light reflection and light transmission usage modes. The conventional image sheet using a translucent or milk-white sheet with reflective and transmissive properties has a density distribution such that a high-density portion that exceeds a set density in the front-side image is not reduced in the back-side image, resulting in a lack of naturalness and clarity in the light transmission usage mode. The present invention provides a solution by reducing the density distribution of the back-side image to a set density or close in value thereto, and a method for forming the image sheet efficiently.
技术功效语段：
The present invention relates to an image sheet that can be used for advertisements and the like in station premises, hotels, department stores, and other places. The image sheet has a front and back side, with both images overlying each other. The density distribution of the back-side image is adjusted to reduce the impact of high-density portions on color production and transmission, resulting in a natural and clear image in both reflection and transmission modes. The invention provides a simple method for adjusting the density distribution of the back-side image, making the sheet easy to manufacture and use.
权利要求：
1. A light-reflection/light-transmission image sheet that includes, on a sheet-like base material that has reflective and transmissive properties, a front-side image and a back-side image that overlie each other with the sheet-like base material interposed therebetween, wherein the density distribution of the back-side image is a density distribution in which a high-density portion that exceeds a set density in the density distribution of the front-side image has been reduced to the set density or a density close in value thereto.
2. The light-reflection/light-transmission image sheet according to claim 1, wherein the set density is set for each of a plurality of set colour segments, and the density distribution of the back-side image is a density distribution in which a high-density portion that exceeds the set density for a corresponding set colour segment in the density distribution for the corresponding set colour segment of the front-side image has been reduced to the set density for the corresponding set colour segment or to a density close in value thereto.
3. A method for forming a light-reflection/light-transmission image sheet including front and back images overlying each other with a sheet-like base material interposed therebetween, the light-reflection/light-transmission image sheet being formed by printing a front-side image on the front side of a sheet-like base material that has reflective and transmissive properties, and printing a back-side image that is the reverse of the front-side image on the back side of the sheet-like base material in a state where the front and back images overlie each other, wherein when printing the back-side image on the back side of the sheet-like base material, the density distribution of the back-side image is a density distribution in which a high-density portion that exceeds a set density in the density distribution of the front-side image has been replaced with the set density or a density that is close in value thereto.
4. The method for forming a light-reflection/light-transmission image sheet according to claim 3, wherein the density distribution of the back-side image is a density distribution in which the high-density portion that exceeds the set density in the density distribution of the front-side image has been replaced with the set density or a density close in value thereto and a portion that is not included in the high-density portion in the density distribution of the front-side image has the same densities as the front-side image.
5. The method for forming a light-reflection/light-transmission image sheet according to claim 3 or 4, wherein the set density is set for each of a plurality of set colour segments, and the density distribution of the back-side image is a density distribution in which a high-density portion that exceeds the set density for a corresponding set colour segment in the density distribution for the corresponding set colour segment of the front-side image has been replaced with the set density for the corresponding set colour segment or a density close in value thereto.
6. The method for forming a light-reflection/light-transmission image sheet according to claim 5, wherein the set colour segment is a colour segment corresponding to a colour expressed in a colour space.
7. The method for forming a light-reflection/light-transmission image sheet according to claim 5 or 6, wherein the set colour segment is a colour segment corresponding to an ink colour.
8. The method for forming a light-reflection/light-transmission image sheet according to any one of claims 3 to 7, wherein the set density is changed according to the transmittance of the sheet-like base material.
9. The method for forming a light-reflection/light-transmission image sheet according to any one of claims 3 to 8, wherein in order to determine the set density, the densities of at least one or more apparent high-density portions in the front-side image are measured using a densitometer.
10. The method for forming a light-reflection/light-transmission image sheet according to claim 9, wherein the densities of at least one or more portions that are not included in the apparent high-density portions in the front-side image are furthermore measured using a densitometer in order to determine the set density.
11. A light-reflection/light-transmission image sheet that includes, on a sheet-like base material that has reflective and transmissive properties, a front-side image and a back-side image that overlie each other with the sheet-like base material interposed therebetween, wherein the density distribution of the back-side image is a density distribution in which the densities in the density distribution of the front-side image have been compressed using a set compression rate.
12. The light-reflection/light-transmission image sheet according to claim 11, wherein the set compression rate is determined for each of a plurality of set colour segments, and the density distribution of the back-side image is a density distribution in which the densities in the density distribution for a corresponding set colour segment of the front-side image have been compressed using the compression rate for the corresponding set colour segment.
13. A method for forming a light-reflection/light-transmission image sheet including front and back images overlying each other with a sheet-like base material interposed therebetween, the light-reflection/light-transmission image sheet being formed by printing a front-side image on the front side of a sheet-like base material that has reflective and transmissive properties, and printing a back-side image that is the reverse of the front-side image on the back side of the sheet-like base material in a state where the front and back images overlie each other, wherein when printing the back-side image on the back side of the sheet-like base material, the density distribution of the back-side image is a density distribution in which the densities in the density distribution of the front-side image have been compressed using a set compression rate.
14. The method for forming a light-reflection/light-transmission image sheet according to claim 13, wherein the set compression rate is determined for each of a plurality of set colour segments, and the density distribution of the back-side image is a density distribution in which the densities in the density distribution for a corresponding set colour segment of the front-side image have been compressed using the compression rate for the corresponding set colour segment.
15. The method for forming a light-reflection/light-transmission image sheet according to claim 14, wherein the set colour segment is a colour segment corresponding to a colour expressed in a colour space.
16. The method for forming a light-reflection/light-transmission image sheet according to claim 14 or 15, wherein the set colour segment is a colour segment corresponding to an ink colour.
17. The method for forming a light-reflection/light-transmission image sheet according to any one of claims 13 to 16, wherein the set compression rate is changed according to the transmittance of the sheet-like base material.
18. A light-reflection/light-transmission image sheet that includes, on a sheet-like base material that has reflective and transmissive properties, a front-side image and a back-side image that overlie each other with the sheet-like base material interposed therebetween, wherein the density distribution of the back-side image is a density distribution in which the density distribution of the front-side image has been adjusted so as to reduce the densities for a corresponding set colour segment based on an adjustment reference for the corresponding set colour segment.
19. A method for forming a light-reflection/light-transmission image sheet including front and back images overlying each other with a sheet-like base material interposed therebetween, the light-reflection/light-transmission image being formed by printing a front-side image on the front side of a sheet-like base material that has reflective and transmissive properties, and printing a back-side image that is the reverse of the front-side image on the back side of the sheet-like base material in a state where the front and back images overlie each other, wherein when printing the back-side image on the back side of the sheet-like base material, the density distribution of the back-side image is a density distribution in which the density distribution of the front-side image has been adjusted so as to reduce the densities for a corresponding set colour segment based on the adjustment reference for the corresponding set colour segment.
20. The method for forming a light-reflection/light-transmission image sheet according to claim 19, wherein the set colour segment is a colour segment corresponding to a colour expressed in a colour space.
21. The method for forming a light-reflection/light-transmission image sheet according to claim 19 or 20, wherein the set colour segment is a colour segment corresponding to an ink colour.
22. The method for forming a light-reflection/light-transmission image sheet according to any one of claims 19 to 21, wherein the adjustment reference is changed according to the transmittance of the sheet-like base material.