GB2056706A - Improvements to printing production - Google Patents

Abstract

British specification No 1,574,411 "Improvements in or relating to Halftone Printing" relates to a colour reproduction method from one halftone screen positioning. The present invention concerns developments therefrom by colour halftone production from black and white, monochrome, photographic originals, for better print from cruciformed halftone in which segmented images for black, and colour work graphically are produced, with fine-etching, retouching methods and a photomechanical process. This provides coarse screen for newsprint and posters and finer quality for art work.

Description

SPECIFICATION Improvements to printing production According to my previous patents in Great Britain numbers 431,384 G.B. 563,028 G.B.

824,769 G.B. 901,412 and following invention number 23161/75 of one halftone screen patterning improvement, dots halftone changed from the usual shapes of chessboard, checkerboard patterning angles, are used with photographic enhancements for black and white, with added colour capacity registration.

Added control for colour reproduction can be obtained with variable flexible shaped dots so that colour originals reproduced with colour filters can be printed by halftone at one screen angling, preferably 45 from the use of G.B. 563,028 specification.

I have shown this method to be extended with the improved application of black and white work, photographs, monochromes, which can be used as originals for colour change printed with one screen dot angling.

Single negatives or multiple images produced in halftone can be retouched or adjusted by fine-etching dot production methods for yellow red blue printing plates, or colours as required wanted in the balance of make-up necessary for the production of printed subjects.

Alternatively some colour results can be produced graphically drawn without the usual colour original filtering photo process, when variation in method of using one screen angled dot position for practically all main halftone work printing enables graphic original creation to be attained with new colour quality and economy.

From a black and white original, photograph or monochrome, one halftone negative made can be used repeatedly when producing printing results required in one, two, three or four colours.

From one enhanced halftone negative optically produced with patent 563,028 stops to absorb retouching effects, one block plate or two can effectively be reproduced without further retouching, fine etching method, for sympathetic complementary two colour printing at less cost.

Where different colour contrasting methods when wanted can be obtained by dot fineetching, retouching for two, three four colour work produced from monochromes, according to circumstances, where one block, plate, or two can be used for two colour printing.

The method of three colour including the black printer, instead of normal four colour method, mentioned in my patent no. 901412 to save time, labour, material, cost in alternative colour process printing, could be used in this later development where the stops of B.P 563,028 extend control for reproduction.

According to my invention of Patent application no. 23161/75 in "Photoengraveyour Printing Plates," changed inking from normal process is used obtained in highlight dot areas made weaker, and in shadow areas made denser, so enabling a bigger range in ink colour plate printing deposition to be obtained.

As grey highlight dots and black shadow tones from the same ink impression of the altered printing plate is obtained, so colour plates similarly produced enable added delicacy from highlights, with stronger colour from the shadows, to be used with agreement on cheaper surfaced paper boards and newsprint hitherto unsuitable for colour printing.

The process can be used better in a variety of ways from a halftone negative. Which can be used to prepare a dot cell inking plate by etching means, or an engraved plate also could be manufactured for more and less inking acceptance, when the usual flat process metal or planographic litho surface is changed by dot-cell surface prepared, manufactured or moulded for process reproductive use.

Being diffeent from the usual all over flat surface plates now used as stock printing plate surfaces for photo engraving photo litho or lithography.

In addition to the photography of type by line and halftone with illustration which can be prepared photomechanically for varied and enhanced inking, type printing by itself can be improved by method on some surfaces applied without process engraving change, when the same basic improvement as from dot-cell inking is conjoined into the type lettering moulded printing surface, so that the flat printing type face is altered when used with added inking applied from recessed cell plate image interposed, so that Headlines for newspapers and other matter displayed, showcards can be printed differently, vividly in black an colour as suitable for advertising print and illustration.

Having now described my invention A process of forming a multi-inked print by a photomechanical process comprising a method of reproducing halftone from black and white or monochrome used at one screen angling for improved dot inking imagery with segmented halftone from my patent 563,028 or 90141 2 for black and coloured process like from 23161/75 conjunction

Claims (6)

CLAIMS (i) preparing a halftone negative using the process of patent specification no 563,028 from a black and white original or monochrome employing a halftone screen (ii) Using the resultant halftone negative to prepare one, two, three or four substantially identical halftone plates (iii) treating each of the said printing plates by etching or otherwise retouching to produce one two three or four different printing plates the extent and manner of the treatment being such as to produce the desired colour balance in the final multicolour print. (iv) Using the resultant plate for a multiinked print and the plates for a multi-colour print and I claim

1. A method of reproducing halftone from black and white and monochrome used at one screen angling for improved dot inking imagery with segmented method from my patents no. 563028 or no 901412 for black inking and coloured process registration.

2. A method of reproduction as in claim one, devised for colour printing when using one halftone negative or one halftone screen positioning for colour manipulation, for fineetching, or retouching, the production of colour.

3. A method of reproduction as in claim 1. for two colour printing use prepared either from A, one halftone negative and one printed plate, or from B, one halftone negative and two printed plated. Or from C, two halftone negatives and two printed plates.

4. A method of reproduction as in claim 1 from one halftone negative for three colour print method of economy for example using 1. yellow and red ink mixture, 2, Blue ink. 3 Black ink.

5. A method of reproduction as in claim 1, for normal colour ink printing methods.

6. A method of printing plate production as in claim one for producing more inking control of use for letterpress process, lithographic process and photo litho printing by known metals, and plate surfaces of synthetic, plastic, photo polymer, sensitised, rubber composition.