Magnetic toner, magnetic developer, apparatus unit, image forming apparatus and facsimile apparatus
First Claim
1. A magnetic toner, comprising a binder resin and a silicon-containing magnetic iron oxide;
- wherein the magnetic iron oxide contains 0.5-4 wt. % silicon based on total iron content, provided that the magnetic iron oxide has a total silicon content (A), a silicon content (B) attributable to siliceous compound contained in a surface layer of the magnetic iron oxide particles and dissolved up to 20 wt. % iron dissolution by hydrochloric acid solution or a mixture of hydrochloric acid solution and hydrofluoric acid solution and a superficial silicon content (C), attributable to siliceous compound contained in a surface layer of the magnetic iron oxide particles and dissolved by an alkali solution, satisfying relations of 44%≦
(B/A)×
100 %≦
84% and 10%≦
(C/A)×
100%≦
55%; and
the magnetic toner has a weight-average particle size of at most 13.5 μ
m and has a particle size distribution such that it contains no more than 50 wt. % of magnetic toner particles having a particle size of at least 12.7 μ
m.
1 Assignment
0 Petitions
Accused Products
Abstract
A magnetic toner for electrophotography is composed from a binder resin and a silicon-containing magnetic iron oxide. The magnetic toner has a weigh-average particle size o at most 13.5 μm and has a particle size distribution such that it contains o more than 50 wt, % of magnetic toner particles having a particle size of at least 12.7 μm. The magnetic toner is able to show high developing performances because of richness in fine particles and is also provided with an improved environmental stability because the magnetic iron oxide used therein contains 0.5-4 wt, % silicon (based on total iron content) and has a specific silicon distribution such that the magnetic iron oxide has a total silicon content (A), a silicon content (B) dissolved together with the magnetic iron oxide when the magnetic iron oxide is dissolved up to 20 wt, % dissolution of iron, and a superficial silicon content (C), satisfying relations of B/A=44-84% and C/A=10-55%. The performances are enhanced if the magnetic toner is blended with additives such as inorganic fine powder or resin fine particles.
47 Citations
132 Claims
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1. A magnetic toner, comprising a binder resin and a silicon-containing magnetic iron oxide;
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wherein the magnetic iron oxide contains 0.5-4 wt. % silicon based on total iron content, provided that the magnetic iron oxide has a total silicon content (A), a silicon content (B) attributable to siliceous compound contained in a surface layer of the magnetic iron oxide particles and dissolved up to 20 wt. % iron dissolution by hydrochloric acid solution or a mixture of hydrochloric acid solution and hydrofluoric acid solution and a superficial silicon content (C), attributable to siliceous compound contained in a surface layer of the magnetic iron oxide particles and dissolved by an alkali solution, satisfying relations of 44%≦
(B/A)×
100 %≦
84% and 10%≦
(C/A)×
100%≦
55%; andthe magnetic toner has a weight-average particle size of at most 13.5 μ
m and has a particle size distribution such that it contains no more than 50 wt. % of magnetic toner particles having a particle size of at least 12.7 μ
m. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29)
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30. A magnetic developer, comprising:
- a magnetic toner, and inorganic fine powder, hydrophobic inorganic fine powder or resin fine particles;
wherein the magnetic toner comprises a binder resin and a silicon-containing magnetic iron oxide; the magnetic iron oxide contains 0.5-4 wt. % silicon based on total iron content, provided that the magnetic iron oxide has a total silicon content (A), a silicon content (B), attributable to siliceous compound contained in a surface layer of the magnetic iron oxide particles and dissolved up to 20 wt. % iron dissolution by hydrochloric acid solution or a mixture of hydrochloric acid solution and hydrofluoric acid solution and a superficial silicon content (C), attributable to siliceous compound contained in a surface layer of the magnetic iron oxide particles and dissolved by an alkali solution, satisfying relations of 44%≦
(B/A)×
100%≦
84% and 10%≦
(C/A)×
100%≦
55%; andthe magnetic toner has a weight-average particle size of at most 13.5 μ
m and has a particle size distribution such that it contains no more than 50 wt. % of magnetic toner particles having a particle size of at least 12.7 μ
m. - View Dependent Claims (31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65)
- a magnetic toner, and inorganic fine powder, hydrophobic inorganic fine powder or resin fine particles;
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66. An apparatus unit, comprising:
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a latent image-bearing member for bearing a latent image thereon and a developing apparatus for developing the latent image;
the developing apparatus including a developer container for containing a developer, a developer-carrying member for carrying and conveying the developer from the developer container to a developing zone facing the latent image-bearing member, and a regulating blade for regulating the developer carried and conveyed by the developer-carrying membe4r into a prescribed thickness to form a thin layer of the developer on the developer carrying member;wherein the developer comprising a magnetic toner comprising a binder resin and a magnetic iron oxide; the magnetic iron oxide contains 0.5-4 wt. % silicon based on total iron content, provided that the magnetic iron oxide has a total silicon content (A), a silicon content (B), attributable to siliceous compound contained in a surface layer of the magnetic iron oxide particles and dissolved up to 20 wt. % iron dissolution by hydrochloric acid solution or a mixture of hydrochloric acid solution and hydrofluoric acid solution and a superficial silicon content (C), attributable to siliceous compound contained in a surface layer of the magnetic iron oxide particles and dissolved by an alkali solution, satisfying relations of 44%≦
(B/A)×
100%≦
84% and 10%≦
(C/A)×
100%≦
55%; andthe magnetic toner has a weight-average particle size of at most 13.5 μ
m and has a particle size distribution such that it contains no more than 50 wt. % of magnetic toner particles having a particle size of at least 12.7 μ
m. - View Dependent Claims (69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132)
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67. An image forming apparatus, comprising:
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a latent image-bearing member for bearing a latent image thereon and a developing apparatus for developing the latent image;
the developing apparatus including a developer container for containing a developer, and a developer-carrying member for carrying and conveying the developer from the developer container to a developing zone facing the latent image-bearing member;wherein the developer comprises a magnetic toner comprising a binder resin and a magnetic iron oxide; the magnetic iron oxide contains 0.5-4 wt. % silicon based on total iron content, provided that the magnetic iron oxide has a total silicon content (A), a silicon content (B), attributable to siliceous compound contained in a surface layer of the magnetic iron oxide particles and dissolved up to 20 wt. % iron dissolution by hydrochloric acid solution or a mixture of hydrochloric acid solution and hydrofluoric acid solution and a superficial silicon content (C), attributable to siliceous compound contained in a surface layer of the magnetic iron oxide particles and dissolved by an alkali solution, satisfying relations of 44%≦
(B/A)×
100%≦
84% and 10%≦
(C/A)×
100%≦
55%; andthe magnetic toner has a weight-average particle size of at most 13.5 μ
m and has a particle size distribution such that it contains no more than 50 wt. % of magnetic toner particles having a particle size of at least 12.7 μ
m.
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68. A facsimile apparatus, comprising:
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an electrophotographic apparatus and a receiving means for receiving image data from a remote terminal; wherein said electrophotographic apparatus comprises a latent image-bearing member for bearing a latent image thereon and a developing apparatus for developing the latent image;
the developing apparatus including a developer container for containing a developer, a developer-carrying member for carrying and conveying the developer from the developer container to a developing zone facing the latent image-bearing member, and a regulating blade for regulating the developer carried and conveyed by the developer-carrying member into a prescribed thickness to form a thin layer of the developer on the developer carrying member;wherein the developer comprises a magnetic toner comprising a binder resin and a magnetic iron oxide; the magnetic iron oxide contains 0.5-4 wt. % silicon based on total iron content, provided that the magnetic iron oxide has a total silicon content (A), a silicon content (B), attributable to siliceous compound contained in a surface layer of the magnetic iron oxide particles and dissolved up to 20 wt. % iron dissolution by hydrochloric acid solution or a mixture of hydrochloric acid solution and hydrofluoric acid solution and a superficial silicon content (C), attributable to siliceous compound contained in a surface layer of the magnetic iron oxide particles and dissolved by an alkali solution, satisfying relations of 44%≦
(B/A)×
100%≦
84% and 10%≦
(C/A)×
100%≦
55%; andthe magnetic toner has a weight-average particle size of at most 13.5 μ
m and has a particle size distribution such that it contains no more than 50 wt. % of magnetic toner particles having a particle size of at least 12.7 μ
m.
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Specification