Thermally developable photosensitive material

A combination of a packaging material and a thermally developable photosensitive material, wherein the packaging material has an oxygen permeating rate at 25° C. of 1.0 ml/atm·m2·day or less and a moisture permeating rate at 25° C. of 1 g/atm·m2·day or less, the thermally developable photosensitive material comprises at least a non-photosensitive organic silver salt, a photosensitive silver halide, a development accelerator, and a reducing agent on the same surface of a substrate, an entire amount of coated silver in the photosensitive material is 0.1 to 1.6 g/m2 and an amount of the reducing agent in the photosensitive material is 0.1 to 1.5 g/m2, and wherein

• 1) a fog density value immediately after thermal developing treatment is 0.20 or less;
• 2) a value of b0* in the following equation (1) at a fog density portion satisfies −20≦b0*<−4;
• and
• 3) a change in an image tone (color difference ΔE) from immediately after thermal developing treatment to after light irradiation as defined in equation (1) satisfies any one of the following condition (a) or the following condition (b):
• ΔE=[(L1*−L0*)2+(a1*−a0*)2+(b1*−b0*)2]1/2 Equation (1)
• wherein L1* and L0* respectively represent metric brightnesses after a point when an amount of time has passed and immediately after thermal developing treatment, in a CIELAB space when observed with a light source used in a medical schaukasten, and a1*, b1* and a0*, b0* represent amounts (color coordinates) of a hue and a chroma after a point when an amount of time has passed and immediately after thermal developing treatment, respectively, in a CIELAB space
• Condition (a):
• ΔE is 1.2 or less when 1000 Lux light is continuously irradiated to the thermally developable photosensitive material for 1 day under an environment of 30° C. and 70% RH,
• Condition (b):
• ΔE is 0.9 or less when 10000 Lux light is continuously irradiated to the thermally developable photosensitive material for 1 day under an environment of 25° C. and 60% RH;
• and the development accelerator is selected from a sulfonamidophenol compound, a compound represented by formula (A-1), or a compound represented by formula (A-2);
• Q1-NHNH-Q2 Formula (A-1)
• wherein in formulae (A-1) and (A-2), Q1 represents an aromatic group which binds to —NHNH-Q2 with a carbon atom, or a heterocyclic group;
• Q2 represents a carbamoyl group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a sulfonyl group, or a sulfamoyl group;
• R1 represents an alkyl group, an acyl group, an acylamino group, a sulfonamido group, an alkoxycarbonyl group, or a carbamoyl group;
• R2 represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryloxy group, an alkyothio group, an arylthio group, an acyloxy group, or a carbonic acid ester group;
• R3 and R4 each represent a group substitutable on a benzene ring;
• and R3 and R4 may be connected to each other to form a fused ring.

An image forming method comprising:

• providing a combination of a thermally developable photosensitive material and a packaging material;
• taking the thermally developable photosensitive material out of the packaging material;
• imagewise exposing a the thermally developable photosensitive material to laser light;
• and
• thermally developing the thermally developable photosensitive material at a developing temperature of 80 to 250° C. for 1 to 15 seconds,
• wherein the packaging material has an oxygen permeating rate at 25° C. of 1.0 ml/atm·m2·day or less and a moisture permeating rate at 25° C. of 1 g/atm·m2·day or less, the thermally developable photosensitive material comprises a non-photosensitive organic silver salt, a photosensitive silver halide, a development accelerator, and a reducing agent on at least one surface of a transparent substrate, an entire amount of coated silver in the photosensitive material is 0.1 to 1.6 g/m2, an amount of the reducing agent in the photosensitive material is 0.1 to 1.5 g/m2, a fog density value immediately after thermal developing treatment is 0.20 or less, a value of b0* in the following equation (1) at a fog density portion satisfies −20≦b0*<−4, and a change in an image tone from immediately after thermal developing treatment to a point when an amount of time has passed as a value of a color difference ΔE as defined in equation (1) is any one of (a) 1.2 or less at 9 months under an environment of 30° C. and 60% RH, (b) 1.2 or less at 3 months under an environment of 40° C. and 40% RH, or (c) 0.9 or less at 1 week under an environment of 45° C. and 40% RH:
• ΔE=[(L1*−L0*)2+(a1*−a0*)2+(b1*−b0*)2]1/2 Equation (1)
• wherein L1* and L0* respectively represent metric brightnesses after a point when an amount of time has passed and immediately after thermal developing treatment, in a CIELAB space when observed with a light source used in a medical schaukasten, and a1*, b1* and a0*, b0* represent amounts (color coordinates) of a hue and a chroma after a point when an amount of time has passed and immediately after thermal developing treatment, respectively, in a CIELAB space;
• and the development accelerator is selected from a sulfonamidophenol compound, a compound represented by formula (A-1), or a compound represented by formula (A-2);
• Q1-NHNH-Q2 Formula (A-1)
• wherein in formulae (A-1) and (A-2), Q1 represents an aromatic group which binds to —NHNH-Q2 with a carbon atom, or a heterocyclic group;
• Q2 represents a carbamoyl group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a sulfonyl group, or a sulfamoyl group;
• R1 represents an alkyl group, an acyl group, an acylamino group, a sulfonamido group, an alkoxycarbonyl group, or a carbamoyl group;
• R2 represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryloxy group, an alkyothio group, an arylthio group, an acyloxy group, or a carbonic acid ester group;
• R3 and R4 each represent a group substitutable on a benzene ring;
• and R3 and R4 may be connected to each other to form a fused ring.

An image forming method comprising:

• providing a combination of a thermally developable photosensitive material and a packaging material;
• taking the thermally developable photosensitive material out of the packaging material;
• imagewise exposing a the thermally developable photosensitive material to laser light;
• and
• thermally developing the thermally developable photosensitive material at a developing temperature of 80 to 250° C. for 1 to 15 seconds,
• wherein the packaging material has an oxygen permeating rate at 25° C. of 1.0 ml/atm·m2·day or less and a moisture permeating rate at 25° C. of 1 g/atm·m2·day or less, the thermally developable photosensitive material comprises
• at least a non-photosensitive organic silver salt, a photosensitive silver halide, a development accelerator, and a reducing agent on the same surface of a substrate, wherein an entire amount of coated silver in the photosensitive material is 0.1 to 1.6 g/m2 and an amount of the reducing agent in the photosensitive material is 0.1 to 1.5 g/m2, and wherein
• 1) a fog density value immediately after thermal developing treatment is 0.20 or less;
• 2) a value of b0* in the following equation (1) at a fog density portion satisfies −20≦b0*<−4;
• and
• 3) a change in an image tone (color difference ΔE) from immediately after thermal developing treatment to after light irradiation as defined in equation (1) satisfies any one of the following condition (a) or the following condition (b):
• ΔE=[(L1*−L0*)2+(a1*−a0*)2+(b1*−b0*)2]1/2 Equation (1)
• wherein L1* and L0* respectively represent metric brightnesses after a point when an amount of time has passed and immediately after thermal developing treatment, in a CIELAB space when observed with a light source used in a medical schaukasten, and a1*, b1* and a0*, b0* represent amounts (color coordinates) of a hue and a chroma after a point when an amount of time has passed and immediately after thermal developing treatment, respectively, in a CIELAB space
• Condition (a):
• ΔE is 1.2 or less when 1000 Lux light is continuously irradiated to the thermally developable photosensitive material for 1 day under an environment of 30° C. and 70% RH,
• Condition (b):
• ΔE is 0.9 or less when 10000 Lux light is continuously irradiated to the thermally developable photosensitive material for 1 day under an environment of 25° C. and 60% RH;
• and the development accelerator is selected from a sulfonamidophenol compound, a compound represented by formula (A-1), or a compound represented by formula (A-2);
• Q1-NHNH-Q2 Formula (A-1)
• wherein in formulae (A-1) and (A-2), Q1 represents an aromatic group which binds to —NHNH-Q2 with a carbon atom, or a heterocyclic group;
• Q2 represents a carbamoyl group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a sulfonyl group, or a sulfamoyl group;
• R1 represents an alkyl group, an acyl group, an acylamino group, a sulfonamido group, an alkoxycarbonyl group, or a carbamoyl group;
• R2 represents a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryloxy group, an alkyothio group, an arylthio group, an acyloxy group, or a carbonic acid ester group;
• R3 and R4 each represent a group substitutable on a benzene ring;
• and R3 and R4 may be connected to each other to form a fused ring.