Photothermographic recording material coatable from an aqueous medium
AssigneeAgfa-Gevaert
InventorsHubert Vandenabeele, Herman Uytterhoeven
Life of this patent
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Abstract
A process for producing an aqueous dispersion I containing particles including a substantially light-insensitive organic heavy metal salt A with a solubility in 100 mL of water of less than 10−3 g at 20° C. comprising the steps of: (i) producing an aqueous dispersion II containing particles containing a salt B with a solubility in 100 mL of water between 1.5 g and 0.001 g at 20° C.; and (ii) converting the salt B in the particles of the aqueous dispersion II into the organic heavy metal salt A, wherein the organic heavy metal salt A and the salt B have a common cation; and a production process for thermographic and photothermographic materials therewith.
Claims12
A process for producing an aqueous dispersion containing particles of a substantially light insensitive silver salt A, said silver salt A being a salt of a carboxylic acid having a solubility of less than 10−3 g in 100 ml of water at 20° C., said process consisting essentially of:
- (a) preparing an aqueous dispersion containing particles of a silver salt B, said silver salt B having a solubility of between 0.001 g and 1.5 g in 100 ml of water at 20° C., wherein the media for said aqueous dispersion is selected from the group consisting of water and mixtures of water and water-miscible organic solvents;
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- (b) reacting said particles of said silver salt B in the aqueous dispersion formed in step (a) with a solution of a conversion agent, wherein said conversion agent is a water soluble salt of the carboxylic acid, thereby forming the aqueous dispersion of particles of said substantially light insensitive silver salt A.
A process for producing an aqueous dispersion containing particles of a substantially light insensitive silver salt A, wherein said silver salt A is a salt of an organic compound with an acidic N—H group having a solubility of less than 10−3 g in 100 ml of water at 20° C., said process consisting essentially of:
- (a) preparing an aqueous dispersion containing particles of a silver salt B, said silver salt B having a solubility of between 0.001 g and 1.5 g in 100 ml of water at 20° C., wherein the media for said aqueous dispersion is selected from the group consisting of water and mixtures of water and water-miscible organic solvents;
- (b) reacting said particles of said silver salt B in the aqueous dispersion formed in step (a) with a solution of a conversion agent wherein said conversion agent is a water soluble salt of the organic compound with an acidic N—H group, thereby forming the aqueous dispersion of particles of said substantially light insensitive silver salt A.
A process for producing a thermographic material comprising a thermosensitive element coated from an aqueous dispersion containing particles of a substantially light insensitive silver salt A, said silver salt A being a salt of an organic compound with an acidic N—H group, said process consisting essentially of:
- (i) preparing an aqueous dispersion containing particles of a silver salt B, said silver salt B having a solubility of between 0.001 g and 1.5 g in 100 ml of water at 20° C.,
- (ii) reacting said particles of said silver salt B in the dispersion produced in step (i) with a solution of a conversion agent, said conversion agent being a water soluble salt of the organic compound with an acidic N—H group, thereby forming the aqueous dispersion of particles of said substantially light insensitive silver salt A, wherein a particle size from 1 to 2 μm is obtained and said silver salt A has a solubility of less than 10−3 g in 100 ml of water at 20° C.;
- (iii) coating onto a support one or more aqueous dispersions or solutions which together include said aqueous dispersion of the light insensitive silver salt A particles resulting from step (ii), an organic reducing agent and a binder including a water-dispersible binder, a water-soluble binder or any mixture thereof, wherein the media for said aqueous dispersions or solutions are selected from the group consisting of water and mixtures of water and water-miscible organic solvents;
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- (iv) drying the resulting one or more coatings to produce the thermosensitive element.
A process for producing a thermographic material comprising a thermosensitive element coated from an aqueous dispersion containing particles of a substantially light insensitive silver salt A, said silver salt A being a salt of a carboxylic acid, said process consisting essentially of:
- (i) preparing an aqueous dispersion containing particles of a silver salt B, said silver salt B having a solubility of between 0.001 g and 1.5 g in 100 ml of water at 20° C.;
- (ii) reacting said particles of said silver salt B in the dispersion produced in step (i) with a solution of a conversion agent, said conversion agent being a water soluble salt of the carboxylic acid, thereby forming the aqueous dispersion of particles including the substantially light insensitive silver salt A, wherein the silver salt A has a solubility of less than 10−3 g in 100 ml of water at 20° C.;
- (iii) coating onto a support one or more aqueous dispersions or solutions which together include the aqueous dispersion of the light insensitive silver salt A particles resulting from step (ii), an organic reducing agent and a binder including a water-dispersible binder, a water-soluble binder or any mixture thereof, wherein the media for said aqueous dispersions or solutions are selected from the group consisting of water and mixtures of water and water-miscible organic solvents;
- (iv) drying the resulting one or more coatings to produce the thermosensitive element.
Dependencies are inferred from the claim text.