Photosensitive materials and imaging processes using such materials

Claim 2

Photosensitive microcapsules useful in the formation of polychromatic images, characterised in that said microcapsules include an internal phase containing a photosensitive composition having a spectral sensitivity range within which said composition hardens upon exposure to radiation, and in that said microcapsules have associated therewith a colour former and an absorber compound which reduces the sensitivity of said microcapsules to actinic radiation over a portion of said spectral sensitivity range.

Claim 3

Photosensitive microcapsules according to Claim 1, further characterised in that said microcapsules include a discrete capsule wall.

Claim 4

Photosensitive microcapsules according to Claim 1 or Claim 2, further characterised in that said absorber compound is present in said internal phase with said photosensitive composition.

Claim 5

Photosensitive microcapsules according to any preceding claim, further characterised in that said photosensitive composition includes an ethylenically unsaturated compound and a photoinitiator.

Claim 6

Photosensitive microcapsules according to Claim 4, wherein said absorber compound is further characterised in that said compound does not substantially inhibit or promote free radical initiated polymerization and said compound possesses an extinction coefficient greater than 100/M cm.

Claim 7

Photosensitive microcapsules according to any preceding claim, further characterised in that said colour former is present within said internal phase.

Claim 8

Photosensitive microcapsules according to any preceding claim, further characterised in that said colour former is selected from cyan, magenta and yellow colour formers.

Claim 9

Photosensitive microcapsules according to any preceding claim, further characterised in that said photosensitive composition is sensitive to ultraviolet radiation.

Claim 10

Photosensitive microcapsules according to Claim 8, further characterised in that said absorber absorbs ultraviolet radiation.

Claim 11

Photosensitive microcapsules according to Claim 9, further characterised in that said absorber is selected from hydroxybenzophenones, hydroxyphenylbenzotriazoles, and formamidines.

Claim 12

Photosensitive microcapsules according to any one of Claims 1 to 7, further characterised in that said photosensitive composition is sensitive to visible light.

Claim 13

A photosensitive material comprising a support having on the surface thereof a layer of photosensitive microcapsules, characterised in that said photosensitive microcapsules include an internal phase containing a photosensitive composition having a spectral sensitivity range within which said composition hardens upon exposure to radiation, and in that said microcapsules have associated therewith a colour former and an absorber compound which reduces the sensitivity of said microcapsules to actinic radiation over a portion of said spectral sensitivity range.

Claim 14

A photosensitive material comprising a support having on the surface thereof a layer of photosensitive microcapsules, characterised in that said photosensitive microcapsules include an internal phase containing a photosensitive composition having a spectral sensitivity range within which said composition hardens upon exposure to radiation, and in that said microcapsules have associated therewith a colour former and an absorber compound which reduces the sensitivity of said microcapsules to actinic radiation over a portion of said spectral sensitivity range.

Claim 15

A photosensitive material comprising a support having on the surface thereof a layer of microcapsules, characterised in that said microcapsules include photosensitive microcapsules according to any of Claims 1 to 11.

Claim 16

Photosensitive material comprising a support having on the surface thereof a layer of photosensitive microcapsules, characterised in that said photosensitive microcapsules include a first set of microcapsules associated with a cyan colour former and containing a first photohardenable composition, a second set of microcapsules associated with a magenta colour former and containing a second photohardenable composition, and a third set of microcapsules associated with a yellow colour former and containing a third photohardenable composition, at least one of said first, second and third sets of microcapsules having associated therewith an absorber which reduces the sensitivity of said microcapsules over a portion of the spectral sensitivity range of the encapsulated photohardenable composition such that said first, second and third sets of microcapsules have sufficiently different sensitivity characteristics that said first photohardenable composition can be hardened upon exposure of said first microcapsules to actinic radiation of a first wavelength without substantially hardening the encapsulated second and third photohardenable compositions, said second photohardenable composition can be hardened upon exposure of said second microcapsules to actinic radiation of a second wavelength without substantially hardening said encapsulated first and third photohardenable compositions, and said third photohardenable composition can be hardened upon exposure of said third microcapsules to actinic radiation of a third wavelength without substantially hardening said encapsulated first and second photohardenable compositions.

Claim 17

Photosensitive material comprising a support having on the surface thereof a layer of photosensitive microcapsules, characterised in that said photosensitive microcapsules include a first set of microcapsules associated with a cyan colour former and containing a first photohardenable composition, a second set of microcapsules associated with a magenta colour former and containing a second photohardenable composition, and a third set of microcapsules associated with a yellow colour former and containing a third photohardenable composition, at least one of said first, second and third sets of microcapsules having associated therewith an absorber which reduces the sensitivity of said microcapsules over a portion of the spectral sensitivity range of the encapsulated photohardenable composition such that said first, second and third sets of microcapsules have sufficiently different sensitivity characteristics that said first photohardenable composition can be hardened upon exposure of said first microcapsules to actinic radiation of a first wavelength without substantially hardening the encapsulated second and third photohardenable compositions, said second photohardenable composition can be hardened upon exposure of said second microcapsules to actinic radiation of a second wavelength without substantially hardening said encapsulated first and third photohardenable compositions, and said third photohardenable composition can be hardened upon exposure of said third microcapsules to actinic radiation of a third wavelength without substantially hardening said encapsulated first and second photohardenable compositions.

Claim 18

Photosensitive material according to Claim 14, further characterised in that at least one of said first, second and third sets of microcapsules is sensitive to ultraviolet radiation.

Claim 19

Photosensitive material according to Claim 14, further characterised in that at least one of said first, second and third photohardenable compositions is sensitive to blue light.

Claim 20

Photosensitive material according to any of Claims 14, 15 or 16, further characterised in that said absorber compound absorbs ultraviolet radiation.

Claim 21

A process for forming an image characterised in that it comprises the steps of image-wise exposing a photosensitive material according to any of Claims 12 to 17; subjecting said microcapsules to a force which causes said microcapsules to release said internal phase and thereby activate said colour former(s); and contacting said released colour former(s) with dry developer which reacts with said colour former(s) to form a colour image.