Exposure of radiation sensitive materials

Claim 1

A method of image-wise exposing a radiation sensitive material which comprises the steps of: (i) providing a resilient blanket which is secured, at its edges, to a flexible support plate which is also secured at its edges so that the resilient blanket and the support plate can adopt a dome-like configuration, (ii) vacuum connecting the resilient blanket to the support plate by a blanket vacuum, (iii) superimposing the radiation sensitive material and an original in the form of a transparent film carrying opaque areas, (iv) causing the resilient blanket and the support plate to adopt said dome-like configuration by means of a contact vacuum which exerts a force stronger than the force exerted by the blanket vacuum so that the radiation sensitive material and the original are urged together by pressure firstly applied at their central areas and then over a successively widening area from the central areas towards the edges of the radiation sensitive material and of the original so as to expel form said edges of the radiation sensitive material and of the original any air present between the radiation sensitive material and the original whereby the radiation sensitive material and the original are in total contact, and (v) directing radiation at the radiation sensitive material through said original.

Claim 2

A method of image-wise exposing a radiation sensitive material which comprises the steps of: (i) providing a resilient blanket which is secured, at its edges, to a flexible support plate which is also secured at its edges so that the resilient blanket and the support plate can adopt a dome-like configuration, (ii) vacuum connecting the resilient blanket to the support plate by a blanket vacuum, (iii) superimposing the radiation sensitive material and an original in the form of a transparent film carrying opaque areas, (iv) causing the resilient blanket and the support plate to adopt said dome-like configuration by means of a contact vacuum which exerts a force stronger than the force exerted by the blanket vacuum so that the radiation sensitive material and the original are urged together by pressure firstly applied at their central areas and then over a successively widening area from the central areas towards the edges of the radiation sensitive material and of the original so as to expel form said edges of the radiation sensitive material and of the original any air present between the radiation sensitive material and the original whereby the radiation sensitive material and the original are in total contact, and (v) directing radiation at the radiation sensitive material through said original.

Claim 3

An apparatus for image-wise exposing radiation sensitive material through an original in the form of a transparent film including opaque areas, which apparatus comprises: (i) a plate carrier, (ii) a support in said plate carrier for supporting the radiation sensitive material and said original, said support comprising a resilient blanket secured at its edges to a flexible support plate which is secured at its edges to the plate carrier, (iii) a means of applying vacuum to the blanket to hold the same against the flexible support plate, (iv) a contact frame including a rigid transparent plate and being capable of sealingly contacting the plate carrier to define a closed chamber containing the radiation sensitive material and said original and bounded by the transparent plate and the support, (v) A means of applying vacuum to said chamber which means generates a larger force than said means of applying vacuum to said blanket to cause said support to adopt a dome-like configuration which firstly urges the central areas of the radiation sensitive material and the original against the transparent plate and then successively applies pressure to wider areas of the radiation sensitive material and the original until total contact occurs between the radiation sensitive material and the original, and (vi) a source of radiation located to direct radiation through said transparent plate and said original and onto the radiation sensitive material.

Claim 4

An apparatus for image-wise exposing radiation sensitive material through an original in the form of a transparent film including opaque areas, which apparatus comprises: (i) a plate carrier, (ii) a support in said plate carrier for supporting the radiation sensitive material and said original, said support comprising a resilient blanket secured at its edges to a flexible support plate which is secured at its edges to the plate carrier, (iii) a means of applying vacuum to the blanket to hold the same against the flexible support plate, (iv) a contact frame including a rigid transparent plate and being capable of sealingly contacting the plate carrier to define a closed chamber containing the radiation sensitive material and said original and bounded by the transparent plate and the support, (v) A means of applying vacuum to said chamber which means generates a larger force than said means of applying vacuum to said blanket to cause said support to adopt a dome-like configuration which firstly urges the central areas of the radiation sensitive material and the original against the transparent plate and then successively applies pressure to wider areas of the radiation sensitive material and the original until total contact occurs between the radiation sensitive material and the original, and (vi) a source of radiation located to direct radiation through said transparent plate and said original and onto the radiation sensitive material.

Claim 6

An apparatus for image-wise exposing radiation sensitive material through an original in the form of a transparent film including opaque areas, which apparatus comprises: (i) a plate carrier, (ii) a support in said plate carrier for supporting the radiation sensitive material and said original, said support comprising a resilient blanket secured at its edges to a flexible support plate which is secured at its edges to the plate carrier, (iii) a contact frame including a rigid transparent plate and being capable of sealingly contacting the plate carrier to define a closed chamber containing the radiation sensitive material and said original and bounded by the transparent plate and the support, (iv) a means of applying vacuum to said chamber to cause said support to adopt a dome-like configuration which firstly urges the central areas of the radiation sensitive material and the original against the transparent plate and then successively applies pressure to wider areas of the radiation sensitive material and the original until total contact occurs between the radiation sensitive material and the original, and (v) a source of radiation located to direct radiation through said transparent plate and said original and onto the radiation sensitive material and further including axially displaceable register pins which are extendible through the support plate and the blanket for cooperation with register pin holes in the radiation sensitive material and the original.

Claim 7

An apparatus for image-wise exposing radiation sensitive material through an original in the form of a transparent film including opaque areas, which apparatus comprises: (i) a plate carrier, (ii) a support in said plate carrier for supporting the radiation sensitive material and said original, said support comprising a resilient blanket secured at its edges to a flexible support plate which is secured at its edges to the plate carrier, (iii) a contact frame including a rigid transparent plate and being capable of sealingly contacting the plate carrier to define a closed chamber containing the radiation sensitive material and said original and bounded by the transparent plate and the support, (iv) a means of applying vacuum to said chamber to cause said support to adopt a dome-like configuration which firstly urges the central areas of the radiation sensitive material and the original against the transparent plate and then successively applies pressure to wider areas of the radiation sensitive material and the original until total contact occurs between the radiation sensitive material and the original, and (v) a source of radiation located to direct radiation through said transparent plate and said original and onto the radiation sensitive material and further including axially displaceable register pins which are extendible through the support plate and the blanket for cooperation with register pin holes in the radiation sensitive material and the original.

Claim 8

An apparatus for image-wise exposing radiation sensitive material through an original in the form of a transparent film including opaque areas, which apparatus comprises: (i) a plate carrier, (ii) a support in said plate carrier for supporting the radiation sensitive material and said original, said support comprising a resilient blanket secured at its edges to a flexible support plate which is secured at its edges to the plate carrier, (iii) a contact frame including a rigid transparent plate and being capable of sealingly contacting the plate carrier to define a closed chamber containing the radiation sensitive material and said original and bounded by the transparent plate and the support, (iv) a means of applying vacuum to said chamber to cause said support to adopt a dome-like configuration which firstly urges the central areas of the radiation sensitive material and the original against the transparent plate and then successively applies pressure to wider areas of the radiation sensitive material and the original until total contact occurs between the radiation sensitive material and the original, and (v) a source of radiation located to direct radiation through said transparent plate and said original and onto the radiation sensitive material wherein the contact frame is perpendicularly movable with respect to the plate carrier between a first position in which it is spaced from the plate carrier and a second position in which it defines said chamber and the apparatus includes a film magazine movable to a position beneath the contact frame, when the contact frame is in its first position, to receive the original from the contact frame after image-wise exposure of the radiation sensitive material.

Claim 9

An apparatus for image-wise exposing radiation sensitive material through an original in the form of a transparent film including opaque areas, which apparatus comprises: (i) a plate carrier, (ii) a support in said plate carrier for supporting the radiation sensitive material and said original, said support comprising a resilient blanket secured at its edges to a flexible support plate which is secured at its edges to the plate carrier, (iii) a contact frame including a rigid transparent plate and being capable of sealingly contacting the plate carrier to define a closed chamber containing the radiation sensitive material and said original and bounded by the transparent plate and the support, (iv) a means of applying vacuum to said chamber to cause said support to adopt a dome-like configuration which firstly urges the central areas of the radiation sensitive material and the original against the transparent plate and then successively applies pressure to wider areas of the radiation sensitive material and the original until total contact occurs between the radiation sensitive material and the original, and (v) a source of radiation located to direct radiation through said transparent plate and said original and onto the radiation sensitive material wherein the contact frame is perpendicularly movable with respect to the plate carrier between a first position in which it is spaced from the plate carrier and a second position in which it defines said chamber and the apparatus includes a film magazine movable to a position beneath the contact frame, when the contact frame is in its first position, to receive the original from the contact frame after image-wise exposure of the radiation sensitive material.

Claim 11

An apparatus for image-wise exposing radiation sensitive material through an original in the form of a transparent film including opaque areas, which apparatus comprises: (i) a plate carrier, (ii) a support in said plate carrier for supporting the radiation sensitive material and said original, said support comprising a resilient blanket secured at its edges to a flexible support plate which is secured at its edges to the plate carrier. (iii) a contact frame including a rigid transparent plate and being capable of sealingly contacting the plate carrier to define a closed chamber containing the radiation sensitive material and said original and bounded by the transparent plate and the support, (iv) a means of applying vacuum to said chamber to cause said support to adopt a dome-like configuration which firstly urges the central areas of the radiation sensitive material and the original against the transparent plate and then successively applies pressure to wider areas of the radiation sensitive material and the original until total contact occurs between the radiation sensitive material and the original, and (v) a source of radiation located to direct radiation through said transparent plate and said original and onto the radiation sensitive material and including a means of applying vacuum to the original to hold the same against the transparent plate after image-wise exposure.

Claim 12

An apparatus for image-wise exposing radiation sensitive material through an original in the form of a transparent film including opaque areas, which apparatus comprises: (i) a plate carrier, (ii) a support in said plate carrier for supporting the radiation sensitive material and said original, said support comprising a resilient blanket secured at its edges to a flexible support plate which is secured at its edges to the plate carrier. (iii) a contact frame including a rigid transparent plate and being capable of sealingly contacting the plate carrier to define a closed chamber containing the radiation sensitive material and said original and bounded by the transparent plate and the support, (iv) a means of applying vacuum to said chamber to cause said support to adopt a dome-like configuration which firstly urges the central areas of the radiation sensitive material and the original against the transparent plate and then successively applies pressure to wider areas of the radiation sensitive material and the original until total contact occurs between the radiation sensitive material and the original, and (v) a source of radiation located to direct radiation through said transparent plate and said original and onto the radiation sensitive material and including a means of applying vacuum to the original to hold the same against the transparent plate after image-wise exposure.