US3854976A

US3854976A - Applicator and method for making a printing form

Info

Publication number: US3854976A
Application number: US00182983A
Authority: US
Inventors: G Ritzerfeld
Original assignee: Individual
Current assignee: Individual
Priority date: 1970-09-25
Filing date: 1971-09-23
Publication date: 1974-12-17
Anticipated expiration: 1991-12-17
Also published as: FR2108292A5; NL7109832A; SE375265B; DE2049019A1; CH562100A5; GB1323965A

Abstract

A carrier foil having a layer of microcapsules containing a printing lacquer consisting of a resin and a solvent. When the carrier foil is superimposed on a printing foil, and the microcapsules broken by the impact of a type or melted by radiation along a desired outline, the lacquer is applied to the printing foil along the desired outline, and adheres to the printing foil when the same is separated from the carrier foil and from the remainder of the layer.

Description

United States Patent 1191 Ritzerfeld 1 Dec. 17, 1974 [54] APPLICATOR AND METHOD FOR MAKING 3,470,059 9/1969 Jonnes 161/119 A PRINTING FORM 3,476,937 1 H1969 Vrancken l l7/36.1 3,484,318 12/1969 Neufeld et a1. 1 161/160 6] n r: Gerhard Ritzerfeld, 1000 Berlin 33 3,505,955 4/1970 Ritzerfeld 117/361 (Dahlem), Germany 3,598,581 8/1971 Reinis 117/37 R 3,697,323 10/1972 Brown, Jr. et al. ll7/36.1

[22] Wed: 1971 3,728,210 4/1973 Piron 161/162 Appl. No.: 182,983

Foreign Application Priority Data Sept. 25, 1970 Germany 2049019 US. Cl l17/36.l, 117/37 R, 161/160, 161/162 Int. Cl. B41m 5/10, C04b 35/00 Field of Search 117/37 R, 36.1; 161/160, 161/162, 168

References Cited UNITED STATES PATENTS 5/1960 Tien 117/36.1 l/l967 Plambeck, .lr. 5/1967 Eichel ll7/36.l

Primary Examiner-William J. Van Balen Attorney, Agent, or Firm-Michael S. Striker 57 ABSTRACT A carrier foil having a layer of microcapsules containing a printing lacquer consisting of a resin and a solvent. When the carrier foil is superimposed on a printing foil, and the microcapsules broken by the impact of a type or melted by radiation along a desired outline, the lacquer is applied to the printing foil along the desired outline, and adheres to the printing foil when the same is separated from the carrier foil and from the remainder of the layer.

10 Claims, 6 Drawing Figures APPLICATOR AND METHOD FOR MAKING A PRINTING FORM BACKGROUND OF THE INVENTION The present invention relates to a method of making a printable image on a lithographic printing foil consisting of metal, preferably aluminum, paper, or a synthetic material, or consisting of several of the aboveenumerated substances, which may form different superimposed foils. The method is carried out by using an applicator sheet, according to the invention, which includes a carrier foil, and a layer of microcapsules bonded to the carrier foil.

In lithographic printing, according to the prior art, a printable image is formed on the printing foil of a fatty substance, or lacquer is applied to the printing foil by a pen or brush. However, fatty substances forming an image, for example of a character, are inferior to a lacquer in forming an adherent base, particularly it is not possible to add to the moistening water, anti-toner substances, since the same creep under the fatty base. When lacquers are used for making a printing foil, it is not possible to produce the desired outline by the types of a typewriter, or by applying infrared heat along the desired outline.

SUMMARY 'OF THE INVENTION It is one object of the invention to overcome the disadvantages of prior-art methods of making a printing foil, and to provide a method which permits the application of any desired substance, particularly lacquer, to the printing foil along a desired outline.

Another object of the invention is to provide a method permitting the use of a typewriter for forming an image consisting of lacquer on a printing foil.

Another object of the invention is to provide a method permitting the use of infrared light for forming an image consisting of a lacquer on a printing foil.

Another object of the invention is to provide a printing foil with a printable outline of an image having great adhesive capacity, permitting the use of moistening liquids, and having great tone stability during printing.

Another object of the invention is to make possible the required anti-toner stability for direct lithographic printing in which the printing face of the printing foil is dried by the paper which is being imprinted.

Another object of the invention is to make a printing foil particularly suited for printing operation in which the printing cylinder is frequently stopped after making a comparatively small number of copies, so that the printing form must be absolutely tone stable after one or two revolutions of the printing cylinder.

Another object of the invention is to provide an applicator sheet for carrying outthe method of the inventron.

Another object of the invention is an applicator sheet comprising a carrier foil, and a layer of microcapsules thereon, preferably containing a lacquer, and adapted to be opened along the outline of a desired image to be printed.

With these objects in view, a method according to the invention of making a printing form, uses a carrier foil having on the front face a layer of microcapsules containing a substance, such as a lacquer. The carrier foil is superimposed on a printing foil so that the layer of capsules is in contact with the front face of the printing foil. Energy is applied to the rear face of one of the foils along the outline of an image so as to open the microcapsules of the layer along the outline whereby the substance released by the opened microcapsules adheres to the front face of the printing foil along the outline.

The printing foil with the adhering substance and the carrier foil with the remaining portions of the layer, are separated from each other so that the substance adhering to the printing foil forms a printable outline of the desired image.

In accordance with the invention, the capsules contain a fast drying oleophilic lacquer consisting of a resin and a solvent.

Energy can be applied along the outline to be printed by the impact of a moving type on the respective foil so that microcapsules are broken along the character outline by the impacts of the type.

Energy can also be applied by heating the outline of the image and the remaining portions of the carrier foil differently, so that the capsules forming the image melt and open. After the evaporation of the solvent, the resin forms a very durable base to which the lithographic printing ink reliably adheres.

The method of the invention can be carried out with different printing foils, for example electrolytically roughened aluminum foils, or brushed aluminum foils. A paper backing may be adhesively attached to the aluminum printing foil, and coated with a water-resistant lacquer. Barite paper, or other lithographic paper foils,

. may also be used as printing foils. Acetate foils, or

a lacquer having at the temperature of 20 Centigrade,

a viscosity between 45 cP and 48 0F.

Preferably the lacquer is a mixture of a copolymerisate with a solvent, such as toluol and xylol.

EXAMPLE 1 22 parts by weight of a copolymerisate consisting of vinylchloride and vinylisobutylether in a ratio of :25 are mixed with 78 parts by weight of toluol.

EXAMPLE 2 21 parts by weight of a copolymerisate consisting of vinylchloride and vinylisobutylether in a ratio of 75:25 are mixed with 79 parts by weight of xylol.

It is preferred to form the layer on the carrier foil of microcapsules having a diameter between 20 micron and 50 micron. The layer is adhesively attached to the carrier sheet.

The novel features'which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following de scription of specific embodiments when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a schematic side view illustrating the use of a typewriter for making a mirror-reversed printable image on a printing form for direct lithographic printing;

- 'FIG. 2 is a schematic side view illustrating the applicator sheet andthe printing foil of FIG. 1 after separation of the printing form from the applicator sheet;

FIGS. 3 and 4 are schematic side views corresponding to FIGS. 1 and 2, but illustrating the making of an offset printing foil with a true image; and

FIGS. and 6 are schematic side views illustrating a modified method using radiation for making a printing form.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the drawing, a carrier foil 1 has a front face to which a layer 2 consisting of microcapsules is adhesively bonded. A printing foil 3 is used. The type bar 5 of a typewriter has a type 4 with a character whose outline is to be represented by the finished printing form. In the method of FIGS. 5 and 6, an infrared lamp 8 is used together with a transparent sheet, to which heatabsorbent material 7 forming the outline-of the desired image is attached.

According to the method as shown in FIGS. 1 and 2, the layer 2 of capsules containing the lacquer is superimposed on the front face of a printing foil 3. The type 4 is moved against the rear face of printing foil 3, and the impact of the type causes breaking of the microcapsules of layer 2 along the outline of the respective character. The broken and opened microcapsules apply lacquer portions to the front face of the printing foil 3, forming with the same a printing form when printing foil 3 is separated from carrier foil I with the remainder of the layer 2. The image 2a is a mirror-reversed image.

In the method shown in FIGS. 3 and 4, the type bar 5 with type 4 is placed at the rear face of the carrier 1 of the layer 2, and the impact along the outline of the character of type 4, breaks capsules along this outline, so that lacquer adheres at 2a to the printing foil 3, formingwith the same a printing form after separation of the carrier sheet I with the remainder oflayer 2 from the

printing form

3,2 a.

In the methods of FIGS. 5 and 6, a printing foil 3 is superimposed on the layer 2 which adheres to the carrier sheet 1. A transparent sheet 6 with heat-absorbing material 7 arranged in accordance with the desired outline. is superimposed on the rear face of carrier foil 1. Infrared light applied by lamp 8 passes through the transparent sheet, and is particularly absorbed by the heat-absorbing, image-forming material 7, so that microcapsules of layer 2 melt and open in'the pattern of the heat-absorbing material 7, so that lacquer adheres in the same pattern at 2a to the printing foil 3. When the

printing form

3,2 a is separated from the carrier sheet I with the remainder of layer 2, the printing foil 3 carries a mirror-reversed image formed of the lacquer portions 20. If a true image is to be made on the printing form, the heat-absorbent material 7 is applied to the rear face of the transparent sheet 6 which directly abuts It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of methods of making a printing form differing from the types described above.

While the invention has been illustrated and described as embodied in a method of making a printing form by means of an applicator sheet consisting of a carrier foil and of a bonded layer of microcapsules containing a lacquer, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

The layer 2 has a thickness from about 20 to about 400 microns.

Typical monomers which may be polymerized in the form of capsules by the process described in the US. Pat. Nos. 2,800,457 and 2,800,458 to Greeniinclude ethylacrylate, methylacrylate, methylmethacrylate, ethylmethacrylate, vinyl acetate, styrene and mixtures thereof.

The adhesive by which the layer 2 is bonded to the carrier foil 1 may comprise resinous acid, casein, a colloidal material, or a synthetic resin dispersion, or a combination of all or some of such substances.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims.

I claim:

l. A method of making a printing form, comprising the steps of providing a printing sheet having a face on which a printable outline of an image is to be formed; providing a carrier sheet having a surface provided with a layer, said layer including microcapsules containing a fast drying oleophilic lacquer comprising a mixture of at least one resin and at least one liquid solvent which is to be transferred at least in part to said face to form said outline contacting said layer with said face; releasing said lacquer from at least some of said microcapsules by transmitting energy to regions of said layer corresponding to said outline so that the released lacquer contacts said face along said outlinelhereby enabling an adherent coating to be formed on said face along said outline; and separating said sheets; whereby a printing form having said outline is obtained.

2. A method as defined in claim 1, wherein said energy is transmitted from said printing sheet to said layer so that said lacquer forms a true outline of said image on said printing form.

3. A method as defined in claim 1, wherein said energy is transmitted from said carrier sheet to said layer so that said lacquer forms a mirror reversed outline of said image on said printing form.

4. A method as defined in claim 1, wherein said resin comprises a copolymer of vinylchloride and vinylisobutylether, said solvent being selected from the group consisting of toluol and xylol.

5. A method as defined in claim 1, said outline being formed by lines of predetermined thickness, and said microcapsules being of substantially the same diameter; and wherein said diameter is smaller than said thickness.

6. A method as defined in claim 5, wherein said diameter is between substantially and 50 microns.

7. A method as defined in claim 1, wherein said lacquer has a viscosity between substantially 45 and 48 cP at a temperature of 20C.

8. A method as defined in claim 1, wherein said step of releasing said lacquer comprises breaking the micro- 6 capsules in said regions by transmitting impact energy thereto.

9. A method as defined in claim 1, wherein said step of releasing said lacquer comprises opening the microcapsules in said regions by preferentially heating the same.

10. A method as defined in claim 9, wherein said energy is transmitted from said carrier sheet to said layer so that said lacquer forms a mirror reversed outline of said image on said printing form.

Claims

1. A METHOD OF MAKING A PRINTING FORM, COMPRISING THE STEPS OF PROVIDING A PRINTING SHEET HAVING A FACE ON WHICH A PRINTABLE OUTLINE OF AN IMAGE IS TO BE FORMED; PROVIDING A CARRIER SHEET HAVING A SURFACE PROVIDED WITH A LAYER, SAID LAYER INCLUDING MICROCAPSULES CONTAINING A FAST DRYING OLEPHILIC LACQUER COMPRISJNING A MIXTURE OF AT LEAST ONE RESIN AND AT LEAST ONE LIQUID SOLVENT WHICH IS TO BE TRANSFERRED AT LEAST IN PART TO SAID FACE TO FOM SAID OUTLINE, SAID LACQUER INCLUDING A MIXTURE OF AT LEAST ONE THERMOPLASTIC RESIN AND AT LEAST ONE LIQUID SOLVENT CONTACTING SAID LAYER WITH SAID FACE; RELEASING SAID LACQUER FROM AT LEAST ONE TSOME OF SAID MICROCAPSULES BY TRANSMITTING ENERGY TO REGIONS OF SAID LAYER CORRESPONDING TO SAID OUTLINE SO THAT THE RELEASED LACQUER CONTACTS SAID FACE ALONG SAID OUTLINE THEREBY ENABLING AN ADHERENT COATING TO BE FORMED ON SAID FACE ALONG SAID OUTLINE; AND SEPARATING SAID SHEETS; WHEREBY A PRINTING FORM HAVING SAID OUTLINE IS OBTAINED.

6. A method as defined in claim 5, wherein said diameter is between substantially 20 and 50 microns.

7. A method as defined in claim 1, wherein said lacquer has a viscosity between substantially 45 and 48 cP at a temperature of 20*C.

8. A method as defined in claim 1, wherein said step of releasing said lacquer comprises breaking the microcapsules in said regions by transmitting impact energy thereto.