Claims
- 1. In an imaging sheet comprising a support and a layer of microcapsules containing an internal phase which includes a radiation sensitive composition which undergoes a change in viscosity upon exposure to actinic radiation, said microcapsules containing an image-forming agent, and said sheet being capable of forming images by image-wise exposing said sheet to actinic radiation and subjecting said microcapsules to a uniform rupturing force whereupon said microcapsules rupture and image-wise release said internal phase; the improvement wherein said sheet is designed to be thermally developed and said microcapsules are thermally rupturable microcapsules characterized in that said microcapsules contain a heat activatable gas generating material which decomposes and generates a sufficient quantity of gas to rupture said microcapsules upon heating said sheet to a temperature of about 90.degree. to 250.degree. C.
- 2. The imaging sheet of claim 1 wherein said heat activatable gas generating material is an azo compound.
- 3. The imaging sheet of claim 1 wherein said microcapsules have discrete walls.
- 4. The imaging sheet of claim 3 wherein said radiation sensitive composition includes an ethylenically unsaturated compound and a photoinitiator.
- 5. In an imaging sheet comprising a support and a layer of microcapsules on said support, said microcapsules having discrete microcapsules walls containing a radiation sensitive composition and a color former in the internal phase, said radiation sensitive composition including an ethylenically unsaturated compound and a photoinitiator such that said radiation sensitive composition undergoes an increase in viscosity upon exposure to actinic radiation, said imaging sheet being capable of forming images by image-wise exposing said imaging sheet to actinic radiation and subjecting said sheet to a uniform rupturing force in the presence of a developer material whereupon said microcapsules rupture and image-wise release said internal phase and said color former reacts with said developer and forms an image; the improvement wherein said imaging sheet is designed to be thermally developed and said microcapsules are thermally rupturable microcapsules characterized in that said microcapsules contain a heat activatable gas generating material which decomposes and generates a sufficient quantity of gas to rupture said microcapsules upon heating said sheet to a temperature of about 90.degree. to 250.degree. C.
- 6. The imaging sheet of claim 5 wherein said heat activatable gas generating material is an azo compound.
- 7. The imaging sheet of claim 5 wherein said sheet further comprises a layer of a developer material interposed between said support and said layer of microcapsules so as to provide a self-contained imaging sheet.
- 8. The imaging sheet of claim 5 wherein a developer material is provided on a support separate and distinct from said support carrying said microcapsules so as to provide in combination with said imaging sheet a transfer imaging system.
- 9. A process for imaging which comprises, in sequence,
- image-wise exposing an imaging sheet comprising a support having on one surface thereof a layer of thermally rupturable microcapsules containing a radiation sensitive composition which undergoes a change in viscosity upon exposure to actinic radiation, and
- uniformly heating said imaging sheet to rupture said microcapsules whereupon said microcapsules image-wise release said internal phase.
- 10. In a process for forming images which comprises image-wise exposing an imaging sheet comprising a support containing in the internal phase an image-forming agent and a radiation sensitive composition which undergoes a change in viscosity upon exposure to actinic radiation, and subjecting said sheet to a uniform rupturing force; the improvement wherein (i) the internal phase of said microcapsules contains a heat activatable gas generating material which decomposes and generates a sufficient quantity of a gas to rupture said microcapsules upon heating to 90.degree. to 250.degree. C.; and (ii) said microcapsules are subjected to said uniform rupturing force by uniformly heating said imaging sheet.
- 11. The process of claim 10 wherein said microcapsules have a discrete capsule wall.
- 12. The process of claim 11 wherein said image-forming agent is a substantially colorless electron donating color former and said heating step is conducted in the presence of an electron accepting color developer.
- 13. The process of claim 10 wherein said process consists essentially of the steps of image-wise exposing said imaging sheet and uniformly heating said imaging sheet to rupture said microcapsules.
- 14. The process of claim 13 wherein said heating step is carried out in the presence of a developer material provided on said imaging sheet.
- 15. The process of claim 13 wherein said heating step is carried out in the presence of a color developer and said developer is provided on a sheet separate and distinct from said imaging sheet.
- 16. The process of claim 12 wherein said thermally rupturable microcapsules are microcapsules formed from a wall material which breaks down upon heating.
- 17. The process of claim 16 wherein said process consists essentially of the steps of image-wise exposing said imaging sheet and heating said imaging sheet to rupture said microcapsules.
- 18. The process of claim 17 wherein said heating step is carried out in the presence of a developer material and said developer material is provided on said imaging sheet.
- 19. The process of claim 17 wherein said heating step is carried out in the presence of a developer material and said developer material is provided on a sheet separate and distinct from said imaging sheet.
Parent Case Info
This application is a continuation of application Ser. No. 517,115 filed July 25, 1983, now abandoned.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
3576660 |
Bayless et al. |
Apr 1971 |
|
Foreign Referenced Citations (2)
Number |
Date |
Country |
17733 |
Aug 1969 |
JPX |
124343 |
Aug 1982 |
JPX |
Continuations (1)
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Number |
Date |
Country |
Parent |
517115 |
Jul 1983 |
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