DE1571832B2 - THERMOGRAPHIC COPYING PROCESS - Google Patents

Description

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The invention relates to a thermograph »- aqueous solution, suspension or dispersion, on-

cal copying process can be brought using a carrier; you can also use a steam

gers with a coating which, when heated, is subjected to crystal separation under vacuum, or

gives off water, so that when heated imagewise they can penetrate the paper or a roughened surface

IR a latent moisture image is formed. 5 surfaces of the carrier are rubbed evenly,

It has already been using a thermal copying process after they have been finely divided.
Infrared exposure proposed, with a copy for the production of the carrier with a carrier that has a coating with substances that can partially or completely release their water of crystallization when made of a material of the infrared exposure specified above, as a binding agent, a natural or synthetic binder which are used to io table resin, z. B. an aqueous copying original and placed in the contact solution or a suspension of gelatin, polyvinyl or reflex arrangement with infrared rays alcohol, polyvinylpyrrolidone or polyvinyl butyral, whereupon a development with a To- When using a water-insoluble polymer ner he follows. a water-permeable poly-

According to the invention, a thermographic 15 merisate is preferred, which is used in the form of a solution in a copying process using a carrier with suitable organic solvents, a coating which gives off water of crystallization when heated with IR a polymerizate of methyl methacrylate and methacrylatentes moisture image is formed, created, acid an ethyl alcohol solution of N-methoxymethyl which is characterized in that the latent 20 polyhexamethylene adipamide or a benzene solution moisture image is first used with a powdery of ethyl cellulose,
in the normal state hard and non-sticky or In this solution, the bound water of crystallization adhering material, which ^{melts at a temperature in the material in the form of a fine powder, range from 70 to 170 0} C and forming an aqueous concentrated solution or a manure metastable liquid is cooled 25 suspension dispersed. The solution obtained in this way or can, developed and for the production of one or more suspension, is then applied to the support, rer copies partially on a further support which is then dried. When using transfers, on which the image obtained is then finally a suspension, a surface is expediently developed. active agent to improve the suspension effect

That is added according to the method according to the invention. On the other hand, the bound can be put to death The copied image is so stable that the material containing the stall water on a support common copier materials with silver salt - are sprayed on by vacuum deposition. Dates The water of crystallization can discolour and deteriorate the quality during application did not take place. According to a further feature of a coating, evaporate under vacuum; if According to the invention, the transferring can take several tens of times, but the material thus obtained for longer be carried out, d. That is, it can be from the intermediate time, in particular during a period of a number of copies or duplicates - at least 10 minutes, left in the air, wrinkles are obtained. the water vapor in the air is absorbed by the

In the case of the thermographic copying process, the connection or the applied mine

According to the invention, any original can be reabsorbed as water of crystallization,

The coating surface of the carrier thus produced

Have an absorption factor against infrared rays. materials is recorded on an original to be copied

In the method according to the invention, the is laid and exposed to infrared rays. Here Incorporation of any particular chemicals can be a transmission copy process or a pure a recording sheet is no longer required and 45 flexion copying processes are used, in addition, the use of a dark room is preferred, the latter being preferred, in which the and the use of any liquids exposure to infrared rays from the side of the unnecessary. The thermographic copying process takes place on the carrier material and the formation of fog Measure of the invention thus represents a drying system. can be decreased and clear images can be obtained

According to a fifth feature of the invention, 5 ° will be possible. ·

cheap and easy copying and duplicating for effortlessly performing reflective copying

procedure created. Process, it is necessary that a carrier material,

The one used in the method according to the invention, which is transparent to infrared rays Carrier is made by being chosen.

onto a carrier material to release at least 55 The image parts of the original absorb the infra Part of the existing water of crystallization reddens to a greater extent than the non-image applies material capable of being heated. As derar- parts and become during the action of the infratiges Material is preferably heated by means of such red rays. Accordingly, that will det, the water of crystallization at a temperature in the carrier material with that described above can release from 40 to 200 ° C. Examples 60 Coating in the places corresponding to the parts of the picture for this purpose compounds such as sodium acetate are tri-heated and the crystals of water of crystallization contain hydrate, tribasic sodium phosphate-12-hydrate, the compound or the crystal water containing Sodium sulfate 10 hydra ^ lead acetate trihydrate, potassium minerals set the water of crystallization under moistening alum-24-hydrate, ammonium-alum-24-hydrate, am- the support surface in the appropriate places moniumferrosu] fat-6-hydrate and minerals such as clay 65 free. The latent moisture image thus formed becomes and bentonite. These compounds and minerals can then be used with the powder developer described above on a carrier, e.g. B. developed in a natural or written way, with besynthetic between the two Resin films, paper or the like, in the form of moist spots and those free of crystal water

Make differences occur in terms of the adhesion of the powder developer and the powder developer adheres more strongly to the moistened areas.

When copying is carried out using the above-described reflective copying method an image of the powder developer that is symmetrical to the original, i. H. a so-called Mirror image obtained, which is particularly desirable in the method according to the invention.

If the infrared rays are exposed for a long time, the crystals set the image part of the original corresponding parts of the carrier material initially free water of crystallization, whereby the carrier material wets and is moistened, and with continued exposure to the infrared rays, water is evaporated, whereby the adhesive property of a powder developer is lowered. Meanwhile the crystals give Carrier material in the parts corresponding to the non-image parts of the original through their water of crystallization the prolonged exposure to infrared rays, reducing the adhesiveness of the powder developer these parts is increased. Therefore, a negative) intermediate material from a positive original can be added long-term exposure to infrared rays (negative mode of operation).

The period of time between the exposure to infrared rays and the development process is preferably as short as possible. The development within z. B. 10 seconds after exposure to the infrared rays can result in a good intermediate material. However, if the lapse of 10 minutes or more, a good image with a high contrast is not obtained after exposure to infrared rays due to the decrease in the difference in adhesiveness of the powder developer. If the exposed intermediate material, ie the material exposed to the action of infrared rays, is left to stand in air for 24 hours or more after exposure without development, this intermediate material can again be used as such in a similar manner to the carrier material with the coating which releases the water of crystallization and is not exposed to any action been exposed to infrared rays \ was used. This is due to the fact that the crystals which had released water of crystallization, when standing in air, again absorb the moisture in the air and in the process revert to the crystals containing water of crystallization.

j. There are different broadcast materials of what some z. B. in the Belgian patents; 631 304 and 644 239 are described. In the process According to the invention, such materials are selected from these which, as indicated above, are not tacky at room temperature, but after melting at a temperature in the range of 70 to 170 ° C are sticky and have a high supercooling capacity have, d. H. have the ability to contribute in a metastable fluid phase Room temperature for a few or more 10 minutes after melting and cooling remain. Typical examples of such transferable materials are plasticizers, mixtures of o- and p-Toluenesulfonamide, plastics made from chlorinated Diphenylene and polyphenylene, benzotriazole, tribenzylamine, vanillin, phthalophenone, 2,4-dihydroxybenzophenone, Benzyl, benzoin, sulfur, acetanilide, benzoic acid and phthalic anhydride.

A finely divided inorganic or organic pigment is used as an infrared ray absorption material used. Particular examples are carbon black, iron oxides, chrome green, ultramarine blue. Co-

.5 pale blue and indigo.

That for developing an exposed intermediate material in the method according to the invention The powder developer used is prepared according to the following procedure: 1 part by weight of a transferable material is thoroughly mixed with 0 to 0.1 part by weight of a finely divided infrared rays absorbent material mixed and heated. When the transferable material melted is, the molten mixture is sufficiently further mixed and cooled to normal temperature. To upon complete solidification of the molten mixture, it is finely pulverized by suitable means and then grained to a grain size of 0.1 to 100 microns in diameter. A mixture from a powder developer (referred to as toner) used in standard electrophotography and finely divided transfer material can be used as a powder developer in the method according to the invention can be used to develop an intermediate material treated with infrared rays.

After a mirror image of an original on the carrier material in the manner described above was formed using the powder developer described above, the intermediate material thus obtained becomes heated by suitable means to bring the temperature to the melting point of the transmissible Material to increase, which is then cooled to room temperature. In doing so, the powder image of the original becomes fixed on this interleaf. The coated side of the intermediate material treated in this way is turned onto a Recording sheet, e.g. B. paper, film, glass, fabric or the like., Placed and heated.

Heating is carried out by placing the assembly between two hot plates or using infrared rays. On the other hand, the surface of the intermediate material can be heated by infrared radiation, whereupon a receiving sheet is placed over it and the assembly is pressed.
Part of the image of the interleaf is transferred to a receiving sheet. When infrared ray heating is used, an infrared ray absorbing material is preferably added to the transfer material.

In this way, the transferable material is transferred onto a receiving sheet. This, transferable Material with the supercooling properties causes powder development when performing immediately after the transfer of the powder developer only to this part due to the adhesiveness of the transferable material adheres to form an image.

As a powder developer for developing a recording sheet, any fine powder can be used of a suitable grain size to apply to a transferable molten material be liable. Suitable powder developers are usually obtained by dispersing them in a thermoplastic resin, z. B. phenol-formaldehyde resin, a molten mixture of chlorinated naphthalene and polystyrene or a copolymer of vinyl chloride and vinyl acetate, a carbonaceous material such as Soot or asphalt powder, an inorganic pigment such as basic lead carbonate, zinc oxide, titanium

Claims (1)

5 6 dioxide, antimony trioxide, iron oxides, cadmium sulfide, the side of the intermediate Basic chromate, molybdenum orange, cadmium yellow, chemical material was applied to an original Chrome green, ultramarine blue or an organic and a reflection copying process, Pigments, such as benzidine yellow, indigo and alizarin and adding the back of the sheet and sheet-like Granulation or graining of the dis- 5 intermediate material produced in this way is exposed to infrared rays persion became grains by an appropriate process. The infrared exposure was carried out using with a diameter of 0.1 to 50 microns focussed on a Thermofax Model 46 Secretary copier posed. A machine designed for common electrophotography. After the exposure, that became used toner arrives in the process according to intermediate material with the above under (1), (a) of the invention to use. The color of such well-defined powder developers has developed. After Developer should be in accordance with the color powder development was created by means of infrared rays of the recording material. heats and fixes the image, taking an intermediate image Powder developers, the surface of which has been preserved with a copy or an intermediate copy, surface-active agent has been treated, a recording sheet was then In the method according to the invention, the surface of the intermediate material is used and, by means of a be det. Heater or by means of infrared radiation from When the material is heated after development the back of the intermediate material is heated to or to melt part of the transfer material with the vapor of an organic solvent such as trichlorethylene, freon, acetone, chloroform or and transfer these onto the recording sheet. When benzene is treated, a visible copy can be produced that of light and moisture can be obtained using a toner for Xerox 914 is not affected and is subject to durable and permanent Office Copier (from Fuji-Xerox CoI, Ltd.) can be. fen, whereupon was fixed in trichlorethylene vapor. Transferring a transferable material to Approximately 30 sheets of prints or copies. hold a sheet or web-shaped absorbent material 25. from a leaf- or web-shaped intermediate biscuit T ie 1 2
material can be repeated several tens of times. The invention is described below with the aid of 10 g of gelatin were dissolved in 200 ml of water. 10 g play explained in more detail. Sodium acetate trihydrate was dissolved, and 20 ml. 30 ethyl alcohol were added with stirring. That B e i s ρ i e 1 1 stirring was continued for a further 2 minutes. (1) making a powder developer f ^ J? ¹ , 9, ^& T? ^h T - ¹⁰ - ^g stearate and for the development of the intermediate material ¹⁰⁰ J ^ ethyl alcohol was chosen in a ball mill. . rend treated for 24 hours to obtain a dispersion (a) 20 g of a powdery plasticizer per 35 obtained. After addition of 30 ml of the dispersion under the base of a mixture of o- and p-toluenesulfonic ter stirring to the above solution amide and 1 g of carbon black were mixed and heated to HO ⁰ C, the mixture was heated on a cellulose to the mixture to melt. The molten triacetate film support applied, a coating of which mixture was stirred and formed in a ^{molten state of 75 ml / m 2;} after drying, the state was mixed, cooled to room temperature and a sheet or web-shaped intermediate material after solidification was kept to a size of less than. The grained or granulated that is between 74 microns in diameter and placed on top of an original. material was used in a corresponding manner, as in the case of (b) 20 g of powdered benzotriazole and 1 g of game 1 described, exposed and developed. ZurEnt soot were mixed and heated to about 100 ° C, winding of the intermediate material was the one in (1), (b) to melt the mixture. Mix the melted 45 powder developer described from Example 1 ver was stirred and thoroughly melted in the. After powder development it became ore Mixed condition; heated to room temperature irradiated with infrared rays, and the image cooled and, after solidified to a size of, was fixed to obtain an intermediate image. Comes 74 'microns or less in diameter. The transmission, development and fixation of the / as TT "ir, ·, · ■ ·. ', 50 intermediate image was created in a similar way as in the case of ■ (2) Production of the intermediate material game 1 described executed. ; . 5 g of gelatin were dissolved in 200 ml of water. 5 g. . . Sodium acetate trihydrate were dissolved and taken under JJ e 1 s ρ 1 e 1 3 Stir mixed with 40 ml of ethyl alcohol. Stirring The work described in Example 1 were continued for an additional 2 minutes. 55 indicate and treatments with the modification (ethyl alcohol serves to promote a favorable out that the sheet or web-shaped intermediate ^ Growth of sodium acetate crystals and of material made by ammonium ferroder Drying.) A mixture of 10 g zinc palm sulfate-6-hydrate pulverized and that through a sieve tat (to reduce fogging) and 100 ml with a mesh size of about 0.074 mm Ethyl alcohol was rubbed evenly into tracing paper in a ball mill while walking powder.
Treated for 24 hours to give a dispersion; 10 ml of the dispersion obtained were the prior claim: solution specified standing added. The resulting mixture was thermographic copying process with thorough stirring. applied to a cellulose triacetate film base, 65 application of a carrier with a coating that ^{gives off water of crystallization around a coating in an amount of 60 ml / m 2} when heated, so that under and a latent one with formation of an intermediate material image-wise heating with IR dried. Moisture pattern is formed, thereby 7 8 indicates that the latent moisture is removed with the formation of a metastable liquid activity pattern initially with a powdery, can be cooled, developed and used to manufacture in the normal state hard and non-sticky development of one or more copies partially on or adhering material that transfers at a temperature to another carrier on which the temperature in the range of 70 to 170 ° C and then the final image is developed.