JPS61287797A - Writing sheet and manufacture thereof - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a writing sheet used for electronic blackboards, whiteboards, etc., which has a surface that allows repeated writing and erasing with a predetermined marker.

<Prior art> In recent years, there has been a remarkable spread of white boards or sheets that can be written on and erased repeatedly in teaching materials and stationery, since chalk is not used, so there is no need to get your hands dirty with powder. Electronic blackboards allow information written on a white writing sheet to be easily manipulated on the spot and copied down to A4 size, etc., so there is no need to take notes each time a meeting is held (meetings). It is attracting attention in various fields because it dramatically increases the efficiency of seminars and seminars.The writing sheets used as surface materials for electronic blackboards and whiteboards, etc. ,
Since there are many things that come with figures such as graphs and illustrations, formats such as monthly schedules, work instructions, Japanese blank maps, golf score sheets, staff notations, grids, etc. are printed in advance on the surface of the writing sheet. It is convenient to have, and there is strong demand from customers.

However, the surface of the writing sheet has physical properties that allow it to be repeatedly written with a designated marker and erased with an eraser. The problem is that the formatting itself is also erased. Further, in the case of an electronic blackboard, a writing sheet for about five screens is usually wound up and rewinded to be electrically driven.

Therefore, since it is necessary to print a different format for each screen of a long writing sheet for five screens in accordance with the customer's requirements, it is difficult to select an appropriate printing method and is quite limited.

For example, when printing on the surface of a writable and erasable film constituting a writing sheet using a screen printing method, which is considered to be relatively suitable for such printing, as mentioned above, due to the releasability of the film surface of fluorine-based materials, etc. Poor adhesion of printing ink (format disappears when trying to erase regular written information many times with an eraser, or during the process of winding up a long writing sheet many times) In addition to the following problems, ■) Cracks occur in the printing ink layer during the winding operation of long writing sheets, and (2) During normal writing operations, erasers may be mistaken for special markers and erased with an eraser. When erasing information recorded with a difficult-to-use marker using an organic solvent, there were problems such as erasing the format itself or causing smearing on the lines.

As a countermeasure to this problem, it may be possible to preform format printing on the surface of a support such as a milky white polyester film, but in this case, 2) It is extremely difficult to continuously print different formats on the printer, 2) Dust easily adheres during the printing process, reducing the commercial value of the product, 3) The thickness of the printing ink layer, which is several tens of micrometers, makes it difficult to apply the adhesive layer. can not do it well.

Due to these problems, it is difficult to find a means for printing in a practically suitable format.

<Problems to be Solved by the Invention> The present invention has been made in view of the above circumstances, and it is possible to print a wide variety of products in small quantities with a relatively simple operation process, and has excellent practicality such as erasure resistance. Format printing with
This makes it possible to apply it to writing sheets used as surface materials for electronic blackboards, whiteboards, and the like.

Means for Solving Problems〉 The support constituting the writing sheet in the present invention is usually a sheet-shaped sheet colored white so that writing on the surface of the writing sheet can be clearly read with a colored marker. For example, 50 to 250 μm milky white polyester film, transparent polyester film with a white pigment layer, white coated paper, synthetic paper, etc. are used, but from the viewpoint of hardness and handling, 100 to 150 μm A milky white polyester film is relatively preferably used.

In addition, the writable and erasable film may be any film in which information written with a marker can be easily erased with an eraser, such as a transparent fluorine-based film or a plastic film having a coating layer of fluorine-based or silicone-based resin. , polypropylene, polyethylene, etc. are applicable to the writable and erasable film of the present invention.

In order to bond the above-mentioned support and the writable/erasable film, an adhesive such as a polyester polyurethane, which is commonly used as an adhesive for dry lamination, is used. Note that in order to bond a writable and erasable film onto a support, it is not necessary to use an adhesive; for example, the support and the film surface themselves may be given an adhesive function in advance, and then heat, pressure bonding, or other means may be used. You can also paste them together.

Furthermore, the sublimable dye ink used in the format printing of the present invention is composed of the following sublimable dye and vehicle components. In other words, disperse dyes are mainly used as sublimable dyes, and for example, C,1,Dis is used as a blue dye.
Anthraquinone dyes such as perse Blue 3, C, 1, DisperseViolet as purple dyes
Azo dyes such as 12, C, T, D 1sperseV
anthraquinone dyes such as iolet 4, ano dyes such as C,1, Disperse Red 17 as red dyes, anthraquinone dyes such as C,1, Disperse Red 4, and C,1, Disper as orange dyes.
Azo dyes such as SE Orange 3 are applicable.

In addition, examples of the resin constituting the vehicle component include ethyl cellulose, hydroxyethyl cellulose, cellulose acetate propionate, alkyd resin, and polyvinyl alcohol, while examples of the solvent constituting the vehicle component include ethyl alcohol, isopropyl alcohol, toluene, and acetic acid. Ethyl, ethylene glycol monoethyl ether, etc. are applicable. The writing sheet of the present invention can be produced using these materials by the following method.

First, a sheet is prepared by laminating a writable and erasable film on a support made of a milky white polyester film or the like by a dry lamination method using a predetermined adhesive.

On the other hand, an original sheet is produced by printing a predetermined format with sublimation dye ink on a base material such as paper using ordinary printing means such as lithographic printing and gravure. In this case, the format is a reverse image printed on the original sheet so that it becomes a fixed image after thermal transfer. Furthermore, at this time, by selecting an arbitrary color for the sublimable dye, it is possible to print in various single colors, or it is also possible to perform full-color printing by applying ordinary photolithography.

Next, the printed side of the original sheet is superimposed on the film surface of a sheet made by laminating a writable and erasable film on a support, and the sublimable dye in the sublimable dye ink is sublimated onto the film side by heat-pressing. Just transcribe it. The conditions for heat-press transfer in this case vary depending on the composition of the sublimable dye and the material of the film, but generally require a temperature of 180°C to 200°C. The writing sheet of the present invention can be obtained by pressure bonding.

In this way, the format image made of sublimable dye printed on the writable and erasable film surface of the writing sheet is not only simply colored on the surface of the film due to the strong penetrating power of the dye molecules, but also the film and It permeates through the adhesive layer and reaches the surface and inside of the support. This enables stable format printing with excellent abrasion resistance on the surface of the writable and erasable film.

The writing sheet of the present invention obtained as described above can be applied to an electronic blackboard by processing it into a long sheet for several screens or an endless sheet, or can be applied to a white board (white board) by pasting it on a board surface such as plywood or metal plate. Alternatively, it can be used as a simple writing sheet by cutting it into an appropriate size without any processing and pasting it on a bulletin board or wall.

<Example> The present invention will be explained in detail with reference to Examples below.

Example 1 A support made of opalescent polyester with a thickness of 125 μm and a writable and erasable film made of a tetrafluoroethylene/ethylene copolymer film (Aflex, manufactured by Asahi Glass Co., Ltd.) with a thickness of 21 μm were bonded with the following composition. A bonded sheet was produced by dry lamination using the coating solution.

Polyester polyurethane resin (Takelac A-54
0 (manufactured by Takeda Pharmaceutical Company, solid content 60%) 100 parts by weight Isocyanate curing agent (Takenate A50 manufactured by Takeda Pharmaceutical Company, solid content 70%) 12 parts by weight Ethyl acetate
On the other hand, using a sublimable dye ink consisting of 50 parts by weight of an anthraquinone disperse dye and 94 parts by weight of a vehicle component consisting of ethyl cellulose, ethyl alcohol, and ethyl acetate, a blue square format was printed on high-quality paper by an offset printing machine. An original sheet was created by applying the following steps.

The format printed side of the obtained original sheet and the writable and erasable film side of the above sheet are superimposed 200
A format image of the sublimable dye was transferred onto the surface of the film using a heating transfer device at .degree. C. to produce a writing sheet of the present invention.

When this writing sheet was applied to an electronic blackboard and a special marker was used to write information such as various letters and numbers using normal operations and a reduced copy was made, a clear copy including the format was obtained. The effectiveness of format printing was confirmed. Furthermore, even if the written information such as letters and numbers was erased many times with an eraser, the format was not erased at all and was extremely stable.

Example 2 Support made of white art paper with a thickness of 140 um and a thickness of 2
1 pm tetrafluoroethylene/ethylene copolymer film (
A writable and erasable film (AFLEX, manufactured by Asahi Glass Co., Ltd.) was dry laminated using the adhesive coating liquid used in Example 1 to prepare a bonded sheet.

On the other hand, a black map of Japan was printed on high-quality paper using an offset printing machine using a sublimable dye ink consisting of 15 parts by weight of a sublimable dye consisting of the combination composition of the following four colors and 85 parts by weight of a vehicle component consisting of ethyl cellulose and ethyl alcohol. An original sheet was created by printing.

The format printed side of the obtained original sheet and the writable and erasable film side of the above sheet are superimposed 200
A format image of the sublimable dye was transferred onto the surface of the film using a heating transfer device at .degree. C. to produce a writing sheet of the present invention.

When the practical characteristics of this writing sheet were evaluated in the same manner as in Example 1, it was confirmed that the writing sheet had excellent characteristics in format printing using sublimable dyes.

Example 3 A support made of a milky white polyester film with a thickness of 125 μI and a writable and erasable film made of a tetrafluoroethylene/ethylene copolymer film (Aflex, manufactured by Asahi Glass Co., Ltd.) with a thickness of 21 pm were used in Example 1. A bonded sheet was produced by dry lamination using the adhesive coating solution obtained.

On the other hand, 15 parts by weight of each of the azo red sublimable dye and the black sublimable dye used in Example 2 and 85 parts by weight of the vehicle component used in Example 2 were kneaded to form two types of red and black. A sublimable ink was created.

Using these two types of sublimation dye inks, an original sheet was produced by performing two-color format printing (red and black) on high-quality paper using an offset printing machine.

The format printed surface of the obtained original sheet and the writable and erasable film of the above sheet were overlapped at 200℃.
A two-color format image was transferred onto the surface of the film using a heating transfer device to prepare a writing sheet of the present invention.

This writing sheet was applied to a thermosensitive electronic blackboard with a color separation mechanism and two-color recording capability, and when predetermined written information was recorded with a marker and a reduced copy was made, the two-color format image on the original sheet was reproduced. A clear copy was obtained. Moreover, even after repeated erasing operations using an eraser, the two-color format remained stable without being erased at all.

<Effects of the Invention> Since the present invention has the above-mentioned configuration, it is possible to print in any format at low cost with simple operations on the surface of the writing/erasable film of the writing sheet used for electronic blackboards, whiteboards, etc. Since the sublimable dye image of the format permeates into the interior of the film and into the support layer, it is not erased even when rubbed with an eraser, making it possible to print an extremely stable format. Especially when applied to electronic blackboards, by preparing multiple original sheets with printed formats separately, it is possible to perform high-mix, low-volume printing processing on each long writing sheet, which can be used for a wide range of purposes. It became possible to apply it to

In addition, by arbitrarily selecting various types of sublimation dye inks for the original image on the original sheet, multicolor or full-color printing is possible on the writing sheet, and a recording mechanism with color separation function is built into the electronic blackboard. Then, you can instantly reduce the large color image on the writing sheet surface and obtain a color copy.

Claims (1)

[Scope of Claims] 1. A writing sheet comprising a writing-erasable film laminated onto a support, the writing sheet having a format printed with a sublimable dye on the side of the film. 2 The printed surface of the original sheet, which has been format-printed with sublimable dye ink on the base material, is superimposed on the film surface of a sheet made by pasting a writable and erasable film on a support, and the sheet is heat-pressed and sublimated. 1. A method for producing a writing sheet, characterized in that format printing is performed by sublimation-transferring a color dye onto the film side.