Metal salts of beta-diketones as charging adjuvants for electrostatic liquid developers

Claim 2

An improved electrostatic liquid developer consisting essentially of (A) a nonpolar liquid having a Kauri-butanol value of less then 30, present in a major amount, (B) thermoplastic resin particles having an average by area particle size of less than 30 μm, (C) a nonpolar liquid soluble ionic or zwitterionic charge director compound, and (D) a β-diketone compound of the general formula: ##STR4## where M is a metal cation; R and R 1 which can be the same or different are alkyl of 1 to 18 carbon atoms, substituted alkyl of 1 to 18 carbon atoms, aryl of 6 to 30 carbon atoms, or substituted aryl of 6 to 30 carbon atoms; n is the valency of the metal; J is 0 to n-1; and X - is OH, Cl, F, sulphate, nitrate, chlorate, phosphate, acetate, alkyl carboxylate of 1 to 18 carbon atoms, or aryl carboxylate of 6 to 30 carbon atoms.

Claim 3

An electrostatic liquid developer according to claim 1 wherein the metal salt of β-diketone is calcium acetylacetonate.

Claim 4

An electrostatic liquid developer according to claim 1 wherein the metal salt of β-diketone is aluminium octadecanoylacetonate.

Claim 5

An electrostatic liquid developer according to claim 1 wherein the metal salt of β-diketone is aluminium benzoylacetonate.

Claim 6

An electrostatic liquid developer according to claim 1 wherein the metal salt of β-diketone is nickel acetylacetonate.

Claim 7

An electrostatic liquid developer according to claim 1 wherein the metal salt of β-diketone is chromium acetylacetonate.

Claim 8

An electrostatic liquid developer according to claim 1 wherein the metal salt of β-diketone is aluminum acetylacetonate.

Claim 9

An electrostatic liquid developer according to claim 1 wherein component (A) is present in 85 to 99.9% by weight, based on the total weight of liquid developer, the total weight of developer solids is 0.1 to 15.0% by weight, and component (C) is present in an amount of 0.25 to 1500 mg/g developer solids.

Claim 10

An electrostatic liquid developer according to claim 8 wherein the metal salt of β-diketone is present in 0.1 to 40% by weight based on the total weight of the developer solids.

Claim 11

An electrostatic liquid developer according to claim 1 containing up to about 60% by weight of a colorant based on the total weight of developer solids.

Claim 12

An electrostatic liquid developer according to claim 10 wherein the colorant is a pigment.

Claim 13

An electrostatic liquid developer according to claim 10 wherein the colorant is a dye.

Claim 14

An electrostatic liquid developer according to claim 1 wherein a fine particle size inorganic oxide is present.

Claim 15

An electrostatic liquid developer according to claim 1 wherein an additional compound is present which is an adjuvant selected from the group consisting of polyhydroxy compound, aminoalcohol, polybutylene succinimide, metallic soap, and an aromatic hydrocarbon.

Claim 16

An electrostatic liquid developer according to claim 10 wherein an additional compound is present which is an adjuvant selected from the group consisting of polyhydroxy compound, aminoalcohol, polybutylene succinimide, metallic soap, and an aromatic hydrocarbon.

Claim 17

An electrostatic liquid developer according to claim 14 wherein a polyhydroxy compound is present.

Claim 18

An electrostatic liquid developer according to claim 14 wherein an aminoalcohol compound is present.

Claim 19

An electrostatic liquid developer according to claim 14 wherein a polybutylene succinimide compound is present.

Claim 20

An electrostatic liquid developer according to claim 14 wherein a metallic soap compound is present dispersed in the resin particles.

Claim 21

An electrostatic liquid developer according to claim 14 wherein an aromatic hydrocarbon compound is present.

Claim 22

An electrostatic liquid developer according to claim 17 wherein the aminoalcohol compound is triisopropanolamine.

Claim 23

An electrostatic liquid developer according to claim 1 wherein the thermoplastic resin is a copolymer of ethylene and an α,β-ethylenically unsaturated acid selected from the group consisting of acrylic acid and methacrylic acid.

Claim 24

An electrostatic liquid developer according to claim 1 wherein the thermoplastic resin is polystyrene.

Claim 25

An electrostatic liquid developer according to claim 1 wherein the thermoplastic resin is a copolymer of ethylene (80 to 99.9%)/acrylic or methacrylic acid (20 to 0%)/alkyl ester of acrylic or methacrylic acid wherein alkyl is 1 to 5 carbon atoms (0 to 20%).

Claim 26

An electrostatic liquid developer according to claim 10 wherein the thermoplastic resin is a copolymer of ethylene (80 to 99.9%)/acrylic or methacrylic acid (20 to 0%)/alkyl ester of acrylic or methacrylic acid wherein alkyl is 1 to 5 carbon atoms (0 to 20%).

Claim 27

An electrostatic liquid developer according to claim 24 wherein the thermoplastic resin is a copolymer of ethylene (90%)/methacrylic acid (10%) having a melt index at 190° C. of 500.

Claim 28

An electrostatic liquid developer according to claim 1 wherein the particles have an average by area particle size of less than 5 μm.

Claim 29

An electrostatic liquid toner according to claim 1 wherein component (C) is an oil-soluble petroleum sulfonate.

Claim 30

An electrostatic liquid toner according to claim 1 wherein component (C) is an anionic glyceride.

Claim 31

A process for preparing electrostatic liquid developer for electrostatic imaging comprising (A) dispersing at an elevated temperature in a vessel a thermoplastic resin and a dispersant nonpolar liquid having a Kauri-butanol value of less than 30, and optionally a colorant, while maintaining the temperature in the vessel at a temperature sufficient to plasticize and liquify the resin and below that at which the dispersant nonpolar liquid degrades and the resin and/or colorant decomposes, (B) cooling the dispersion, either (1) without stirring to form a gel or solid mass, followed by shredding the gel or solid mass and grinding by means of particulate media with or without the presence of additional liquid; (2) with stirring to form a viscous mixture and grinding by means of particulate media with or without the presence of additional liquid; or (3) while grinding by means of particulate media to prevent the formation of a gel or solid mass with or without the presence of additional liquid; (C) separating the dispersion of toner particles having an average particle size of less than 30 μm from the particulate media; (D) adding to the dispersion a nonpolar liquid soluble ionic or zwitterionic charge director compound; and (E) adding during any of steps (A), (B), (C) or (D) a metal salt of the general formula: ##STR5## where M is a metal cation; R and R 1 which can be the same or different are alkyl of 1 to 18 carbon atoms, substituted alkyl of 1 to 18 carbon atoms, aryl of 6 to 30 carbon atoms, or substituted aryl of 6 to 30 carbon atoms; n is the valency of the metal; J is 0 to n-1; and X - is OH, Cl, F, sulphate, nitrate, chlorate, phosphate, acetate, alkyl carboxylate of 1 to 18 carbon atoms, or aryl carboxylate of 6 to 30 carbon atoms.

Claim 32

A process for preparing electrostatic liquid developer for electrostatic imaging comprising (A) dispersing at an elevated temperature in a vessel a thermoplastic resin and a dispersant nonpolar liquid having a Kauri-butanol value of less than 30, and optionally a colorant, while maintaining the temperature in the vessel at a temperature sufficient to plasticize and liquify the resin and below that at which the dispersant nonpolar liquid degrades and the resin and/or colorant decomposes, (B) cooling the dispersion, either (1) without stirring to form a gel or solid mass, followed by shredding the gel or solid mass and grinding by means of particulate media with or without the presence of additional liquid; (2) with stirring to form a viscous mixture and grinding by means of particulate media with or without the presence of additional liquid; or (3) while grinding by means of particulate media to prevent the formation of a gel or solid mass with or without the presence of additional liquid; (C) separating the dispersion of toner particles having an average particle size of less than 30 μm from the particulate media; (D) adding to the dispersion a nonpolar liquid soluble ionic or zwitterionic charge director compound; and (E) adding during any of steps (A), (B), (C) or (D) a metal salt of the general formula: ##STR5## where M is a metal cation; R and R 1 which can be the same or different are alkyl of 1 to 18 carbon atoms, substituted alkyl of 1 to 18 carbon atoms, aryl of 6 to 30 carbon atoms, or substituted aryl of 6 to 30 carbon atoms; n is the valency of the metal; J is 0 to n-1; and X - is OH, Cl, F, sulphate, nitrate, chlorate, phosphate, acetate, alkyl carboxylate of 1 to 18 carbon atoms, or aryl carboxylate of 6 to 30 carbon atoms.

Claim 33

A process according to claim 30 wherein the metal salt of β-diketone is calcium acetylacetonate.

Claim 34

A process according to claim 30 wherein the metal salt of β-diketone is aluminum acetylacetonate.

Claim 35

A process according to claim 30 wherein the metal salt of β-diketone is aluminium octadecanoylacetonate.

Claim 36

A process according to claim 30 wherein the metal salt of β-diketone is aluminium benzoylacetonate.

Claim 37

A process according to claim 30 wherein the metal salt of β-diketone is nickel acetylacetoneate.

Claim 38

A process according to claim 30 wherein the metal salt of β-diketone is chromium acetylacetonate.

Claim 39

A process according to claim 30 wherein there is present in the vessel up to 100% by weight of a polar liquid having a Kauri-butanol value of at least 30, the percentage being based on the total weight of the developer liquid.

Claim 40

A process according to claim 30 wherein the particulate media are selected from the group consisting of stainless steel, carbon steel, ceramic, alumina, zirconia, silica, and sillimanite.

Claim 41

A process according to claim 30 wherein the thermoplastic resin is a copolymer of ethylene and an α,β-ethylenically unsaturated acid selected from the group consisting of acrylic acid and methacrylic acid.

Claim 42

A process according to claim 30 wherein the thermoplastic resin is a copolymer of ethylene (80 to 99.9%)/acrylic or methacrylic acid (20 to 0%)/alkyl ester of acrylic or methacrylic acid wherein alkyl is 1 to 5 carbon atoms (0 to 20%).

Claim 43

A process according to claim 40 wherein the thermoplastic resin is a copolymer of ethylene (90%)/methacrylic acid (10%) having a melt index at 190° C. of 500.

Claim 44

A process according to claim 30 wherein the charge director compound is an oil-soluble petroleum sulfonate.

Claim 45

A process according to claim 30 wherein the charge director is an anionic glyceride.

Claim 46

A process according to claim 30 wherein the additional nonpolar liquid, polar liquid, or combinations thereof is present to reduce the concentration of toner particles to between 0.1 to 15 percent by weight with respect to the liquid.

Claim 47

A process according to claim 44 wherein the concentration of toner particles is reduced by additional nonpolar liquid.

Claim 48

A process according to claim 30 wherein cooling the dispersion is accomplished while grinding by means of particulate media to prevent the formation of a gel or solid mass with or without the presence of additional liquid.

Claim 49

A process according to claim 30 wherein cooling the dispersion is accomplished without stirring to form a gel or solid mass, followed by shredding the gel or solid mass and grinding by means of particulate media with or without the presence of additional liquid.

Claim 50

A process according to claim 30 wherein cooling the dispersion is accomplished with stirring to form a viscous mixture and grinding by means of particulate media with or without the presence of additional liquid.

Claim 51

A process according to claim 30 wherein an adjuvant compound selected from the group consisting of polyhydroxy compound, aminoalcohol, polybutylene succinimide, metallic soap, and aromatic hydrocarbon is added during the dispersing step (A).

Claim 52

A process according to claim 49 wherein the adjuvant compound is an aminoalcohol.

Claim 53

A process according to claim 50 wherein the aminoalcohol is triisopropanolamine.

Claim 54

A process according to claim 44 wherein an adjuvant compound selected from the group consisting of polyhydroxy compound, aminoalcohol, polybutylene succinimide, metallic soap, and an aromatic hydrocarbon is added to the liquid developer.

Claim 55

A process according to claim 52 wherein the adjuvant compound is a polyhydroxy compound.

Claim 56

A process according to claim 53 wherein the polyhydroxy compound is ethylene glycol.

Claim 57

A process according to claim 52 wherein the adjuvant compound is a metallic soap dispersed in the resin particles.

Claim 58

A process according to claim 55 wherein the adjuvant compound is aluminium tristearate.

Claim 59

A process for preparing electrostatic liquid developer comprising (A) dispersing a colorant in a thermoplastic resin in the absence of a dispersant nonpolar liquid having a Kauri-butanol value of less than 30 to form a solid mass, (B) shredding the solid mass, (C) grinding the shredded solid mass by means of particulate media in the presence of a liquid selected from the group consisting of a polar liquid having a Kauri-butanol value of at least 30, a nonpolar liquid having a Kauri-butanol value of less than 30, and combinations thereof, (D) separating the dispersion of toner particles having an average particle size of less than 30 μm from the particulate media, (E) adding additional nonpolar liquid, polar liquid or combinations thereof to reduce the concentration of toner particles to between 0.1 to 15.0 percent by weight with respect to the liquid; (F) adding to the dispersion a liquid soluble ionic or zwitterionic charge director compound, and (G) adding during any of steps (A), (B), (C), (D), (E), or (F) a metal salt of a β-diketone according to claim 1.

Claim 60

A process for preparing electrostatic liquid developer comprising (A) dispersing a colorant in a thermoplastic resin in the absence of a dispersant nonpolar liquid having a Kauri-butanol value of less than 30 to form a solid mass, (B) shredding the solid mass, (C) redispersing the shredded solid mass at an elevated temperature in a vessel in the presence of a dispersant nonpolar liquid having a Kauri-butanol value of less than 30, while maintaining the temperature in the vessel at a temperature sufficient to plasticize and liquify the resin and below that at which the dispersant nonpolar liquid degrades and the resin and/or colorant decomposes, (D) cooling the dispersion, either (1) without stirring to form a gel or solid mass, followed by shredding the gel or solid mass and grinding by means of particulate media with or without the presence of additional liquid; (2) with stirring to form a viscous mixture and grinding by means of particulate media with or without the presence of additional liquid; or (3) while grinding by means of particulate media to prevent the formation of a gel or solid mass with or without the presence of additional liquid; (E) separating the dispersion of toner particles having an average particle size of less than 30 μm from the particulate media, and (F) adding additional nonpolar liquid, polar liquid or combinations thereof to reduce the concentration of toner particles to between 0.1 to 15.0 percent by weight with respect to the liquid; (G) adding to the dispersion a liquid soluble ionic or zwitterionic charge director compound, and (H) adding during any of steps (A), (B), (C), (D), (E), (F) or (G) a metal salt of a β-diketone according to claim 1.