Patent ID: 9579833
Date: 2017-02-28
CPC Classifications: B29C,B29K,B41M

Claim:
1. A method of forming a three-dimensional image, the method comprising: forming a first print image on a first surface of a thermally expandable sheet which includes a thermally expandable layer formed on one surface of a base sheet; forming a second print image on a region of a second surface of the thermally expandable sheet, wherein the second print image is a mirror image of the first print image, wherein the region of the second surface corresponds to the first print image of the first surface, and wherein a density of a light absorbing photothermal conversion material contained in the second print image is set based on a density of a color image photothermal conversion material contained in the first print image; and forming a three-dimensional image of the first print image by selectively expanding the thermally expandable layer with a thermal energy that is generated in both the first print image and the second print image when irradiating the thermally expandable sheet with light from the second surface of the thermally expandable sheet, wherein the thermal energy generated in the first print image and the second print image is dependent upon the density of the color image photothermal conversion material contained in the first print image and the density of the light absorbing photothermal conversion material contained in the second print image, respectively, wherein the second print image is formed with a first density of the light absorbing photothermal conversion material at a first part of the second print image and with a second density of the light absorbing photothermal conversion material at a second part of the second print image, wherein the first density of the light absorbing photothermal conversion material of the second print image is lower than the second density of the light absorbing photothermal conversion material of the second print image, wherein the first part of the second print image corresponds to a first part of the first print image, and the second part of the second print image corresponds to a second part of the first print image, wherein a first density of the color image photothermal conversion material of the first part of the first print image is higher than a second density of the color image photothermal conversion material of the second part of the first print image, and wherein the three-dimensional image of the first print image is formed by uniformly irradiating the thermally expandable sheet with the light so that the thermally expandable sheet corresponding to the first part of the first print image expands to a same bulge height as the thermally expandable sheet corresponding to the second part of the first print image.