Printing screen and method of making same
OwnerFrank A. Sportelliinventor
Life of this patent
Estimating the term…
Abstract
A printing plate is made in accordance with a particular method and is used in a printing process wherein it is effective to produce a substantially continuous tone printing effect. A negative screen having an overall pattern defined by rows of closely spaced substantially square-shaped areas is exposed two times on an image carrier. An image screen pattern is developed on the image carrier wherein each of the two exposures of the overall pattern on the negative screen is effected at an angle of 30.degree. with respect to each other. A unique printing screen pattern is obtained which is then used for printing a reproduced image.
Claims20
A method of making a photoprinting image element, said method comprising:
- (a) providing a negative screen having two sets of parallel equispaced lines located thereon, each said set being perpendicular to each other,
- (b) providing a photographic film to be exposed,
- (c) exposing the negative screen onto the photographic film in two separate exposures,
- (d) said negative screen being disposed at a predetermined angle in each said separate exposure,
- (e) each said predetermined angle being at a different angle with respect to each other, and
- (f) developing the exposed photographic film to produce a photoprinting image element having a regular screen pattern as shown in FIG. 2.
In the method of making a printing screen pattern, the process comprising:
- (a) providing a negative screen having an overall pattern defined by rows of closely spaced substantially square-shaped areas,
- (b) providing a light sensitive image carrier effective to receive two exposures of said overall pattern on the negative screen, exposing said carrier to said two exposures, and
- (c) developing an image screen pattern as shown in FIG. 2 on said image carrier wherein each of said two exposures of said overall pattern on said negative screen is effected at a different angle on said image carrier.
A light transmitting plate having a predetermined design of indicia thereon, said plate comprising:
- (a) an indicia bearing side,
- (b) said indicia being disposed on said indicia bearing side and being composed of photographically opaque material,
- (c) said predetermined design as shown in FIG. 2.
Dependencies are inferred from the claim text.