JPS5913018B2 - Method and device for thinning photographic paper - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for thinning printed photographic paper.

More specifically, printed photographic paper is made into a thin layer containing an image layer and a white reflective layer, and this is laminated or pasted into plastic cards used as identification cards, credit cards, train tickets, etc. The present invention relates to a method and apparatus for making thinned photographic paper for use in printing. Conventional ID cards, etc. have the card name, date of issue, expiration date, etc. printed on the front and back sides of an intermediate white opaque plastic sheet, and transparent plastic sheets are provided on both sides of the sheet, but they cannot be counterfeited or tampered with. From the viewpoint of preventing unauthorized use due to loss, it is desirable to have a photo card with the user's own photo on the card.

Various types of photo cards have been proposed up to now. Part 1
The first step is to cut the card user's photo to an appropriate size.
This method involves pasting it on a plastic card or covering the card with a plastic sheet. However, the cards are made by using an imprinter to transfer the uneven embossing marks made on the card onto a slip made of carbon paper or pressure-sensitive paper. The above-mentioned photo ID card has a disadvantage in that the photo portion is raised and the slip is stained by the imprinter. Therefore, a photo card that is flat and has no protrusions is desired.

For this purpose, a thin layer of the photograph is inserted between the plastic sheets.
A flat photographic plastic card has been devised which solves the above-mentioned drawbacks by laminating it. The thin layered photograph needs to be about 100 microns or less thin, and if it is thinner than this, a flat card without bubbles can be produced when laminated. For example, the Fujiris ortho stripping type (manufactured by Fuji Photo Film Co., Ltd.) has a peeling layer between the support layer and the image film, and the image layer can be easily peeled off, so the thin layer described above You can use it as a photo.

However, it is difficult to obtain photographs using this type of special photosensitive material from general card users, and the photographs must be retaken using ordinary black and white photographic paper or color photographic paper. It is therefore an object of the present invention to provide a method for making laminated photographic paper for plastic cards without using special photographic paper.

Another object is to provide a method and apparatus for thinning photographic paper particularly suitable for plastic coated photographic paper. That is, the present invention includes a step of peeling off a part of the support layer layer-by-layer from the photographic paper support, and a step of grinding the remaining support layer using a grindstone to a predetermined thickness, leaving the image layer and white reflective layer. This invention relates to a method and apparatus for thinning photographic paper in step 2.

One embodiment will be described below with reference to the drawings.

The photographic paper used here is a plastic coated color photographic paper with a thin layer of polyethylene. As shown in Figure 1, the layer structure of this color photographic paper is as follows: 1 thin polyethylene layer 1
and 2, a base paper 3 and an image layer 4. The thin polyethylene layer 2 contains a white pigment such as titanium dioxide to have white reflective properties. Image layer 4 is a multilayer color emulsion layer with a gelatin binder. The back side of this color photographic paper 5, that is, a part of the polyethylene layer 1 and the base paper 3 are peeled off using a knife 11, as shown in FIGS. 2A and 2B.

This color photographic paper is placed flat on a suction table face down and scraped with a knife 11. The blade edge of the knife 11 may be sharp and flat or serrated, but it is preferable that it be as thin as possible. (Another method is to rotate the milling machine at high speed and use it to scrape off the back side of the color photographic paper.) The color photographic paper 5, which was initially about 250μ thick, was peeled off with a razor blade. 100
It was possible to achieve a thickness of approximately 150 μm. Paper fibers of the base paper 3 remain on the peeling surface 6. Next, the remaining base paper 6
is ground by a rotary grinding wheel 12 to a specified thickness leaving the image layer 4 and the white reflective layer 2.

Grinding with #48 grinding wheel 12 was done in one stage, but #3
Grinding with the grinding wheel 12 of #0 and #48 was performed in one stage, but it may be done in the first stage with #30 and the second stage with #48, which is more effective. At this time, the paper powder easily adhered to the grindstone, so it was necessary to remove it.As a result, the image layer and white reflective layer 2 were left and the layer was thinned to about 50 to 60 microns. The quality of the image on this thinned photographic paper remained the same as the original without any loss. Insert this between the PVC film and the printed white PVC film and
When thermocompression bonded at ~120°C and 2-5 kg/Cd, a plastic card with no irregularities on the surface and no air bubbles could be produced. Furthermore, although paper fibers still remained in the thinned photographic paper according to this example, they did not have any adverse effect on the surface of the plastic card. On the contrary, it was found that the paper fibers penetrated into the plastic card, improving its adhesion. In the second embodiment, the grinding wheel 12
Instead, a vapor grinder was kept rotating, and the photographic paper was lightly pressed against it to thin the layer.

At this time, it was difficult to make the surface pressed uniformly, so it was necessary to be very careful. Next, an embodiment of the apparatus according to the present invention will be described in detail with reference to FIG.

In FIG. 3, photographic paper 21 to be thinned is placed on a cushion table 22. In FIG. The suction surface 23 of the suction table 22 may be made of porous sintered metal, so that when the suction table 22 is peeled off thinly, there is no effect of unevenness due to the suction holes. Although not shown, there is a suction box below the suction surface 23, which is connected to a pressure reduction system. This suction table 22 is sent in the direction of the arrow by a feeding mechanism 24. The peeling knife 25 has an endless strip shape and is rotated by a drive wheel 26 and a drive motor 27.
The position of the peeling knife 25 is stabilized by rollers 28, 2.9. A thin, double-edged type with sharpened edges on both sides is best. Further, the blade may be flat or serrated. The dust suction device 30 is for sucking up paper dust generated during peeling. Suction table 22
The photographic paper 21 set on top is first moved on the table while peeling off the polyethylene layer on the back side and part of the base paper using the peeling knife 25, and then moves to the next grinding process using a grinding wheel. The grinding wheel 31 is rotated at high speed by a drive motor so that the direction of movement of the suction table 22 is opposite to the direction of movement of the photographic paper.

There is a specified distance between the surface of the grinding wheel and the surface of the suction table, and the surface of the photographic paper that protrudes beyond this distance is ground. Since ground paper powder tends to adhere to the grindstone surface, compressed air is ejected from a high-pressure air nozzle 32 to blow away the paper powder, which is then sucked up by a dust suction device 33.
Grinding using a grinding wheel may be performed in one stage, but it is more efficient to perform the grinding in two stages using grinding wheels with different meshes. In this embodiment, a rotary grinding wheel was used for grinding, but it goes without saying that a disk-shaped grinding wheel or a vibrating grinding wheel may also be used. As explained above, by peeling with a knife and grinding with a grindstone, thinned photographic paper suitable for plastic cards can be efficiently obtained without damaging the image.

Moreover, since ordinary black and white or color photographic paper is used as is, there is no need for special photographic paper or re-photographing, and it is possible to laminate the photographs you have on the card.

Furthermore, according to the method of the present invention, photos can be stored not only on ID cards but also on magnetic cards, commuter passes, plastic photo frames, etc.
It can also be applied to cases such as plastic lamination.

[Brief Description of the Drawings] Figure 1 is a cross-sectional view showing the layer structure of plastic-coated photographic paper, Figures 2A and b are explanatory diagrams showing the steps of the method according to the present invention, and Figure 3 is an apparatus according to the present invention. It is a figure showing an example of. 2... White reflective layer, 3... Base paper, 4...
...Image layer, 5...Photographic paper, 11...
...Knife, 1.2... Grinding wheel, 21...
...Photographic paper, 22...Sa, Kushion table, 24...Movement mechanism, 25...Band knife, 31...Whetstone, 32... ... High pressure air nozzle, 30, 33 - ... Dust suction device.

Claims (1)

[Claims] 1. A first step of peeling off a part of the support layer of the photographic paper layer by layer, and grinding the remaining support layer of the photographic paper using a grindstone moving at high speed to separate the image layer and the white color. A method for thinning photographic paper including an image layer and a white reflective layer, comprising a second step of peeling off to a predetermined thickness while leaving a reflective layer. 2. A movable suction table for suctioning and fixing the photographic paper flat, a knife for peeling off part of the support layer of the photographic paper, and a high-speed moving knife for grinding the remaining support layer. A device for thinning photographic paper, consisting of a grindstone.