Photohardenable element

• US 3,867,153 A
• Filed: 09/11/1972
• Issued: 02/18/1975
• Est. Priority Date: 09/11/1972
• Status: Expired due to Term

• Current Assignee: Alexander Maclachlan
• Original Assignee: Alexander Maclachlan
• Inventors: MacLachlan, Alexander
• Primary Examiner(s): Lesmes, George F.
• Assistant Examiner(s): Lipsey, Charles E.
• Application Number:
  US05/287,666
• Time in Patent Office: 890 Days
• Field of Search: 161/1,36,39,145,147,149,166,410,411,412 156/272 96/35.1,115R,115P,67,78,79
• US Class Current: 430/5
• CPC Class Codes: G03C 3/00 Packages of films for inserting into cameras, e.g. roll-films, film-packs; Wrapping materials for light-sensitive plates, films or papers, e.g. materials characterised by the use of special dyes, printing inks, adhesives wrapping materials in general B65D
• CPC Class Codes: G03F 7/027 Non-macromolecular photopolymerisable compounds having carbon-to-carbon double bonds, e.g. ethylenic compounds G03F7/075 takes precedence
• CPC Class Codes: G03F 7/168 Finishing the coated layer, e.g. drying, baking, soaking
• CPC Class Codes: G03F 7/2022 Multi-step exposure, e.g. hybrid; backside exposure; blanket exposure, e.g. for image reversal; edge exposure, e.g. for edge bead removal; corrective exposure
• CPC Class Codes: Y10S 428/913 Material designed to be responsive to temperature, light, moisture
• CPC Class Codes: Y10T 428/24752 Laterally noncoextensive components
• CPC Class Codes: Y10T 428/24777 Edge feature
• CPC Class Codes: Y10T 428/24967 Absolute thicknesses specified

Abstract

An improved photohardenable element is provided which comprises (1) a support, (2) photohardenable layer and (3) a protective cover sheet laminated to the surface of said photohardenable layer. The improvement consists of hardening a small continuous region along the edges of the photohardenable layer, i.e., by selectively exposing the region to actinic radiation. The major portion of said photohardenable layer is between said narrow continuous regions and is substantially unhardened and enexposed to actinic radiation, said narrow continuous regions being at least 0.00005 inches wide and of sufficient width to prevent excessive laminar flow of the photohardenable layer caused by pressure and temperature when the element is in stacked sheet or roll form.

Claims

1. IN A PHOTOHARDENABLE ELEMENT, COMPRISING A SUPPORT, A HIGHLY PLASTICIZED PHOTOHARDENABLE LAYER AND A PROTECTIVE COVER SHEET, THE IMPROVEMENT WHEREIN SAID PHOTOHARDENABLE LAYER HAS BEEN HARDENED TO PROVIDE NARROW CONTINUOUS REGIONS OF HARDENED MATERIAL ALONG ITS EDGES AND WHEREIN THE MAJOR PORTION OF SAID PHOTOHARDENABLE LAYER IS BETWEEN SAID NARROW CONTINUOUS REGIONS AND IS SUBSTNTIALLY UNHARDENED AND UNEXPOSED TO ACTINIC RADIATION, SAID NARROW CONTINUOUS REGIONS BEING AT LEAST 0.00005 INCHES WIDE AND OF SUFFICIENT WIDTH TO PREVENT EXCESSIVE LAMINAR FLOW OF THE PHOTOHARDENABLE LAYER CAUSED BY PRESSURE AND TEMPERATURE WHEN THE ELEMENT IS STACKED SHEET OR ROLL FORM.

2. The photohardenable element of claim 1 wherein said photohardenable layer is a photopolymerizable layer.

3. The photohardenable element of claim 1 wherein said photohardenable layer is a photocrosslinkable layer.

4. The photohardenable element of claim 1 wherein said narrow continuous region of hardened material is about 0.00005 to about 0.05 inch wide.

5. The photohardenable element of claim 1 wherein said narrow continuous region of hardened material is photohardened.

6. The photohardenable element of claim 1 wherein said narrow continuous region of hardened material is between said support and said protective cover sheet.

7. The photohardenable element of claim 1 wherein said narrow continuous region of hardened material is disposed along at least two parallel edges of said photohardenable element.

8. The photohardenable element of claim 1 wherein said hardened material contains a colorant.