Liquid developer for electrostatic photography

Claim 2

A process for supplementing a liquid developer in an electrostatic photography apparatus, comprising supplying a starting liquid developer to an electrostatic photography apparatus, the starting liquid developer containing a colorant, a binder and a charge control agent in a nonpolar insulating carrier liquid; consuming a portion of the starting liquid developer such that it becomes difficult to obtain an adequate electrostatic photography image when using the starting liquid developer; and then supplementing a supplemental liquid developer in the electrostatic photography aparatus, characterized by the improvement in that the supplemental liquid developer has a composition of a colorant, a binder and a charge control agent in a nonpolar insulating carrier liquid, different from a composition of the starting liquid developer such that the supplemented liquid developer in the electrostatic photography apparatus maintains a state of charge of the colorant and the binder within a predetermined state suitable for electrostatic photography.

Claim 3

A process according to claim 1, wherein at least one of the colorant, the binder and the charge control agent of the supplemental liquid developer are different from those of the starting liquid developer.

Claim 4

A process according to claim 1, wherein an amount ratio of the colorant, the binder and the charge control agent of the supplemental liquid developer is different from that of the starting liquid developer.

Claim 5

A process according to claim 1, wherein an amount ratio of the charge control agent to the colorant and the binder of the supplemental liquid developer is substantially smaller than that of the starting liquid developer.

Claim 6

A process according to claim 4, wherein the ratio of the charge control agent to the colorant and the binder of the supplemental liquid developer is less than 80% of that of the starting liquid developer.

Claim 7

A process according to claim 5, wherein the ratio of the charge control agent to the colorant and the binder of the supplemental liquid developer is less than half of that of the starting liquid developer.

Claim 8

A process according to claim 6, wherein the ratio of the charge control agent to the colorant and the binder of the supplemental liquid developer is less than one third of that of the starting liquid developer.

Claim 9

A process according to claim 7, wherein the ratio of the charge control agent to the colorant and the binder of the supplemental liquid developer is less than one fourth of that of the starting liquid developer.

Claim 10

A process according to claim 4, wherein the charge control agents and amounts thereof of the starting and supplemental liquid developers are selected from the following combinations (amounts being based on parts by weight): ______________________________________ Starting liquid developer Supplemented liquid developer ______________________________________ (1) gum rosin 30-40 parts gum rosin 5-10 (2) gum rosin 30-40 disproportionated 10-20 rosin (3) hydrogenated rosin 20-30 hydrogenated rosin 5-10 (4) polymerized rosin 30-40 polymerized rosin 10-15 (5) disproportionated 20-30 disproportionated 5-10 rosin rosin (6) acrylic acid 1-5 acrylic acid 0.1-0.8 (7) crotonic acid 1-3 crotonic acid 0.2.-0.7 (8) maleic acid 0.5-2.5 maleic acid 0.1-0.4 (9) itaconic acid 0.4-3 itaconic acid 0.05-0.3 (10) citraconic acid 0.5-1.5 citraconic acid 0.1-0.4 (11) anhydrous maleic 0.5-3 anhydrous maleic 0.1-0.4 acid acid (12) anhydrous itaconic 0.3-3 anhydrous itaconic 0.05-0.2 acid acid (13) dimethyl maleate 2-8 dimethyl maleate 0.4-1.2 (14) glycidil 0.7-5 glycidil 0.1-0.5 methacrylate methacrylate (15) oxyethyl acrylate 2-5.5 oxyethyl acrylate 0.6-1.5 (16) zirconium 10-30 zirconium 5-10 naphtenate naphtenate (17) aluminum stearate 30-40 aluminum stearate 10-20 (18) cobalt naphtenate 10-20 cobalt naphtenate 2-5 (19) lead naphtenate 20-30 lead naphtenate 10-15 (20) zirconium octenate 10-20 zirconium octenate 1-5 ______________________________________

Claim 11

A process for supplementing a liquid developer in an electrostatic photography apparatus, comprising supplying a starting liquid developer to an electrostatic photography apparatus, the starting liquid developer containing a colorant, a binder and a charge control agent in a nonpolar insulating carrying liquid; consuming a portion of the starting liquid developer and changing the state of charge of the colorant and binder in the liquid developer; and supplementing a supplemental liquid developer in the electrostatic photography apparatus, characterized by the improvement in that the supplemental liquid developer contains a colorant, a binder and a charge control agent in a nonpolar insulating carrier liquid, a product of a multiplication of a strength of imparting a charge by a concentration of the charge control agent in the supplemental liquid developer being substantially smaller than that of the starting liquid developer such that the supplemented liquid developer in the electrostatic photography apparatus maintains a state of a charge of the colorant and the binder within a predetermined state suitable for electrostatic photography, wherein the charge control agents of the starting and supplemental liquid developers are selected from the following chemicals and the strengths of imparting a charge of the charge control agent are taken from the following: ______________________________________ Strength of Charge Charge Control Agent Imparting ______________________________________ acrylic acid 5 methacrylic acid 4 crotonic acid 1 maleic acid 10 phthalic acid 3 itaconic acid 8 citraconic acid 7 anhydrous acrylic acid 4 anhydrous methacrylic acid 4 dimethyl aminomethylmethacrylate 6 anhydrous maleic acid 10 anhydrous itaconic acid 7 glycidil methacrylate 5 dimethyl maleate 6 diethyl maleate 6 dimethyl phthalate 2 ethyl crotonate 1 diethyl phthalate 2 dimethylamine laurate 7 ______________________________________

Claim 12

A process for supplementing a liquid developer in an electrostatic photography apparatus, comprising supplying a starting liquid developer to an electrostatic photography apparatus, the starting liquid developer containing a colorant, a binder and a charge control agent in a nonpolar insulating carrying liquid; consuming a portion of the starting liquid developer and changing the state of charge of the colorant and binder in the liquid developer; and supplementing a supplemental liquid developer in the electrostatic photography apparatus, characterized by the improvement in that the supplemental liquid developer contains a colorant, a binder and a charge control agent in a nonpolar insulating carrier liquid, a product of a multiplication of a strength of imparting a charge by a concentration of the charge control agent in the supplemental liquid developer being substantially smaller than that of the starting liquid developer such that the supplemented liquid developer in the electrostatic photography apparatus maintains a state of a charge of the colorant and the binder within a predetermined state suitable for electrostatic photography, wherein the charge control agents of the starting and supplemental liquid developers are selected from the following chemicals and the strengths of imparting a charge of the charge control agent are taken from the following: ______________________________________ Strength of Charge Charge Control Agent Imparting ______________________________________ acrylic acid 5 methacrylic acid 4 crotonic acid 1 maleic acid 10 phthalic acid 3 itaconic acid 8 citraconic acid 7 anhydrous acrylic acid 4 anhydrous methacrylic acid 4 dimethyl aminomethylmethacrylate 6 anhydrous maleic acid 10 anhydrous itaconic acid 7 glycidil methacrylate 5 dimethyl maleate 6 diethyl maleate 6 dimethyl phthalate 2 ethyl crotonate 1 diethyl phthalate 2 dimethylamine laurate 7 ______________________________________

Claim 13

A process according to claim 10, wherein the product of the supplemental liquid developer is less than 80% of that of the starting liquid developer.

Claim 14

A process according to claim 11, wherein the product of the supplemental liquid developer, is less than half of that of the starting liquid developer.

Claim 15

A process according to claim 3, wherein the product of the supplemental liquid developer is less than one third of the starting liquid developer.

Claim 16

A process according to claim 14, wherein the product of the supplemental liquid developer is less than one fourth of the starting liquid developer.

Claim 17

A kit comprising individual starting and supplemental liquid developers for electrostatic photography, the starting and supplemental liquid developers containing a colorant, a binder and a charge control agent in a nonpolar insulating carrier liquid, in which the supplemental liquid developer has a composition different from that of the starting liquid developer in at least one of the ingredients and concentrations thereof such that a state of charge of the colorant and the binder of the starting liquid developer varied by repeated use for electrostatic photography, the varied state of charge of the colorant and the binder being not suitable for electrostatic photography, is returned to a state of a charge of the colorant and the binder suitable for electrostatic photography by combination with the supplemental liquid developer.

Claim 18

A kit comprising individual starting and supplemental liquid developers for electrostatic photography, the starting and supplemental liquid developers containing a colorant, a binder and a charge control agent in a nonpolar insulating carrier liquid, in which the supplemental liquid developer has a composition different from that of the starting liquid developer in at least one of the ingredients and concentrations thereof such that a state of charge of the colorant and the binder of the starting liquid developer varied by repeated use for electrostatic photography, the varied state of charge of the colorant and the binder being not suitable for electrostatic photography, is returned to a state of a charge of the colorant and the binder suitable for electrostatic photography by combination with the supplemental liquid developer.

Claim 19

A combination according to claim 15, wherein at least one of the colorant, the binder and the charge control agent of the supplemental liquid developer are different from those of the starting liquid developer.

Claim 20

A combination according to claim 15, wherein ratio of the colorant, the binder and the charge control agent of the supplemental liquid developer is different from that of the starting liquid developer.

Claim 21

A combination according to claim 15, wherein a ratio of the charge control agent to the colorant and the binder of the supplemental liquid developer is substantially smaller than that of the starting liquid developer.

Claim 22

A combination according to claim 18, wherein the ratio of the charge control agent to the colorant and the binder of the supplemental liquid developer is less than 80% of that of the starting liquid developer.

Claim 23

A combination according to claim 19, wherein the ratio of the charge control agent to the colorant and the binder of the supplemental liquid developer is less than half of that of the starting liquid developer.

Claim 24

A combination according to claim 20, wherein the ratio of the charge control agent to the colorant and the binder of the supplemental liquid developer is less than one third of that of the starting liquid developer.

Claim 25

A combination according to claim 21, wherein the ratio of the charge control agent to the colorant and the binder of the supplemental liquid developer is less than one fourth of that of the starting liquid developer.

Claim 26

A combination according to claim 18, wherein the charge control agents and amounts thereof of the starting and supplemental liquid developers are selected from the following combinations (the amount being based on parts by weight): ______________________________________ Starting liquid developer Supplemented liquid developer ______________________________________ (1) gum rosin 30-40 gum rosin 5-10 (2) gum rosin 30-40 disproportionated 10-20 rosin (3) hydrogenated rosin 20-30 hydrogenated rosin 5-10 (4) polymerized rosin 30-40 polymerized rosin 10-15 (5) disproportionated 20-30 disproportionated 5-10 rosin rosin (6) acrylic acid 1-5 acrylic acid 0.1-0.8 (7) crotonic acid 1-3 crotonic acid 0.2-0.7 (8) maleic acid 0.5-2.5 maleic acid 0.1-0.4 (9) itaconic acid 0.4-3 itaconic acid 0.05-0.3 (10) citraconic acid 0.5-1.5 citraconic acid 0.1-0.4 (11) anhydrous maleic 0.5-3 anhydrous maleic 0.1-0.4 acid acid (12) anhydrous itaconic 0.3-3 anhydrous itaconic 0.05-0.2 acid acid (13) dimethyl maleate 2-8 dimethyl maleate 0.4-1.2 (14) glycidil 0.7-5 glycidil 0.1-0.5 methacrylate methacrylate (15) oxyethyl acrylate 2-5.5 oxyethyl acrylate 0.6-1.5 (16) zirconium 10-30 zirconium 5-10 naphtenate naphtenate (17) aluminum stearate 30-40 aluminum stearate 10-20 (18) cobalt naphtenate 10-20 cobalt naphtenate 2-5 (19) lead naphtenate 20-30 lead naphtenate 10-15 (20) zirconium octenate 10-20 zirconium octenate 1-5 ______________________________________

Claim 27

A kit comprising individual starting and supplemental liquid developers for electrostatic photography, the starting and supplemental liquid developers containing a colorant, a binder and a charge control agent in a nonpolar insulating carrier liquid, in which a product of a multiplication of a strength of imparting a charge to the colorant and binder by a concentration of the charge control agent in the supplemental liquid developer is substantially smaller than that of the starting liquid developer, and wherein the charge control agents of the starting and supplemental liquid developer are selected from the following chemicals and the strengths of imparting a charge of the charge control agents are taken from the following: ______________________________________ Strength of Charge Charge Control Agent Imparting ______________________________________ acrylic acid 5 methacrylic acid 4 crotonic acid 1 maleic acid 10 phthalic acid 3 itaconic acid 8 citraconic acid 7 anhydrous acrylic aid 4 anhydrous methacrylic acid 4 dimethyl aminomethylmethacrylate 6 anhdrous maleic acid 10 anhydrous itaconic acid 7 glycidil methacrylate 5 dimethyl maleate 6 diethyl maleate 6 dimethyl phthalate 2 ethyl crotonate 1 dimethl crotonate 2 diethyl phthalate 2 dimethylamine laurate 7 ______________________________________

Claim 28

A kit comprising individual starting and supplemental liquid developers for electrostatic photography, the starting and supplemental liquid developers containing a colorant, a binder and a charge control agent in a nonpolar insulating carrier liquid, in which a product of a multiplication of a strength of imparting a charge to the colorant and binder by a concentration of the charge control agent in the supplemental liquid developer is substantially smaller than that of the starting liquid developer, and wherein the charge control agents of the starting and supplemental liquid developer are selected from the following chemicals and the strengths of imparting a charge of the charge control agents are taken from the following: ______________________________________ Strength of Charge Charge Control Agent Imparting ______________________________________ acrylic acid 5 methacrylic acid 4 crotonic acid 1 maleic acid 10 phthalic acid 3 itaconic acid 8 citraconic acid 7 anhydrous acrylic aid 4 anhydrous methacrylic acid 4 dimethyl aminomethylmethacrylate 6 anhdrous maleic acid 10 anhydrous itaconic acid 7 glycidil methacrylate 5 dimethyl maleate 6 diethyl maleate 6 dimethyl phthalate 2 ethyl crotonate 1 dimethl crotonate 2 diethyl phthalate 2 dimethylamine laurate 7 ______________________________________

Claim 29

A combination according to claim 24, wherein the product of the supplemental liquid developer in less than 80% of that of the starting liquid developer.

Claim 30

A combination according to claim 25, wherein the product of the supplemental liquid developer is less than half of that of the starting liquid developer.

Claim 31

A combination according to claim 26, wherein the product of the supplemental liquid developer is less than one third of the starting liquid developer.

Claim 32

A combination according to claim 27, wherein the product of the supplemental liquid developer is less than one fourth of the starting liquid developer.