US 4,077,830 A · Laminate and method for protecting photographic element

Abstract

A laminate having particular characteristics is used in securing a protective sheet over the emulsion surface of a photographic element such as negatives, positives, slides, glass plates, microfilm, movie film, etc. The optical and mechanical characteristics of the laminate include a protective sheet of transparent, wear-resistant plastic coated with a pressure-sensitive adhesive so that the total thickness of the protective sheet and the adhesive is less than 0.004 inches. The adhesive transmits a major portion of incident ultra violet light and is non-degradable in ultra violet light, and a release sheet of resin material covers the adhesive coating until application to the photographic element when the release sheet is stripped away. Both the protective sheet and the release sheet have a surface finish of less than 10-millionths of an inch RMS so that both the adhesive surface and the protective sheet surface are very smooth when the release sheet is stripped away.

Claims4

Dependent claims

A protective, optically clear laminate formed of a thin, protective sheet of transparent resin material having a thin coating of transparent, pressure-sensitive adhesive covered by a release sheet, said laminate being wound in a roll before use and said laminate being used by removing said release sheet and pressing said adhesive against the emulsion surface of a photographic element having a developed image to preserve the optical properties of said image of said photographic element during a period when said photographic element is in use for contact printing, said laminate being characterized by:

a. both surfaces of said protective sheet having a surface finish of less than 10-millionths of an inch RMS;
b. said release sheet being formed of resin material with both surfaces having a surface finish of less than 10-millionths of an inch RMS;
c. the surface of said adhesive coating that is exposed when said release sheet is stripped away having a surface finish conforming to said release sheet and being less than 10-millionths of an inch RMS;
d. said exposed surface of said adhesive having said surface finish of less than 10-millionths of an inch RMS being in contact with said emulsion surface of said photographic element when said laminate is in use;
and
e. the total thickness of said protective sheet and said adhesive being less than 0.002 inches.

3 more elements

A method of protecting the emulsion surface of a photographic element having a developed image to preserve the optical properties of said image of said photographic element during a period when said photographic element is in use for contact printing, said method comprising:

a. selecting and acquiring a thin, protective sheet of transparent resin material having a surface finish of less than 10-millionths of an inch RMS and being less than 0.001 inches thick;
b. selecting and acquiring a transparent, pressure-sensitive adhesive capable of bonding said protective sheet to said emulsion surface;
c. coating a thin layer of said adhesive on said protective sheet so said layer is less than 0.001 inches thick;
d. selecting and acquiring a resin release sheet having a surface finish of less than 10-millionths of an inch RMS;
e. covering said adhesive layer with said resin release sheet;
f. smoothing said adhesive layer by winding up said adhesive-coated protective sheet and said release sheet so the surface of said adhesive layer contacting said release sheet is pressed against said release sheet to conform to said release sheet and acquire a surface finish of less than 10-millionths of an inch RMS;
g. unwinding said adhesive-coated protective sheet and said release sheet;
h. stripping said release sheet away from said adhesive-coated protective sheet to expose said adhesive surface having a finish of less than 10-millionths of an inch RMS;
i. pressing said adhesive layer against said emulsion surface to secure said protective sheet to said photographic element;
and
j. said selection and acquisition of said protective sheet, said adhesive, and said release sheet with said surface finish giving said adhesive layer said surface finish all cooperating to form a substantially distortion-free optical path from said emulsion surface through said adhesive and said protective sheet so said image of said photographic element can be used for contact printing with said protective sheet in place preventing damage to said emulsion surface.

8 more elements

Dependencies are inferred from the claim text.

Laminate and method for protecting photographic element

Life of this patent

Laminate and method for protecting photographic element

Life of this patent

Abstract

Claims4