US5025272A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dot exposure type image forming apparatus
Assignee: Konica Minolta Inc
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Filing: 1989-12-26
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Granted: 1991-06-18
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Expires: 2009-12-26
Abstract
Abstract The invention provides an apparatus for forming a toner image by reversal development. In the apparatus, there are provided an electric charger for uniformly charging a photoreceptor to a given electrostatic potential; the photoreceptor discharging in response to an exposure light to form an electrostatic latent image, the photoreceptor having a predetermined light decay curve indicating a relation between an amount of the exposure light and a discharged potential on the exposed portion wherein an absolute value of the differential coefficient of the light decay curve is small when the amount of the exposure light is small and the value sharply becomes large when the amount of the exposure light increases; a laser beam exposure device for exposing the photoreceptor with a dot-shaped light beam; and a developing device for providing toner onto the exposed portion of the latent image, thereby forming a toner image.
Inventors
- 👤 Satoshi Haneda
- 👤 Hiroyuki Nomori
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 18:04
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/024; H04N1/032; H04N1/036; G; G03; G03G; G03G13/00; G03G13/01; G03G13/22; G03G5/00; G03G5/02; G03G5/04; G03G5/05; G03G5/0528; G03G5/0557; G03G5/0567; H04N1/40; H04N1/405; H04N1/4055; H04N1/4056
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
197 words
An apparatus for forming a toner image by reversal development, comprising: a charging means for uniformly charging a photoreceptor to a given electrostatic potential; said photoreceptor discharging in response to an exposure light to form an electrostatic latent image, said photoreceptor having a predetermined light decay curve indicating a relation between an amount of the exposure light and a discharged potential on the exposed portion wherein an absolute value of the differential coefficient of the light decay curve is small when the amount of the exposure light is small and said value sharply becomes large when the amount of the exposure light increases; an exposure means for exposing said photoreceptor with a dot-shaped light; and a developing means for providing toner onto said exposed portion of said latent image, thereby forming a toner image, wherein said light decay curve satisfies the relationship < E 1/2/E 9/10 E 9/10 being a light sensitivity of said photoreceptor when said electrostatic potential has decayed to 9/10 of that at the start of said exposure and E 1/2 is a light sensitivity of said photoreceptor when said electrostatic potential has decayed to 1/2 of that at the start of said exposure.
Claim 2
Independent Claim
197 words
An apparatus for forming a toner image by reversal development, comprising: a charging means for uniformly charging a photoreceptor to a given electrostatic potential; said photoreceptor discharging in response to an exposure light to form an electrostatic latent image, said photoreceptor having a predetermined light decay curve indicating a relation between an amount of the exposure light and a discharged potential on the exposed portion wherein an absolute value of the differential coefficient of the light decay curve is small when the amount of the exposure light is small and said value sharply becomes large when the amount of the exposure light increases; an exposure means for exposing said photoreceptor with a dot-shaped light; and a developing means for providing toner onto said exposed portion of said latent image, thereby forming a toner image, wherein said light decay curve satisfies the relationship < E 1/2/E 9/10 E 9/10 being a light sensitivity of said photoreceptor when said electrostatic potential has decayed to 9/10 of that at the start of said exposure and E 1/2 is a light sensitivity of said photoreceptor when said electrostatic potential has decayed to 1/2 of that at the start of said exposure.
Claim 3
Dependent Claim
17 words
The apparatus of claim 1, wherein said light decay curve satisfies the following relation; 2≦(E 1/2)/(E 9/10).
Claim 4
Dependent Claim
22 words
The apparatus of claim 1, wherein said photoreceptor includes a photoconductive layer containing semiconductive particles, and wherein said semiconductive particles contain phthalocyanine.
Claim 5
Dependent Claim
22 words
The apparatus of claim 1, wherein said photoreceptor includes a photoconductive layer containing thermosetting resin in which photoconductive semiconductive particles are dispersed.
Claim 6
Dependent Claim
20 words
The apparatus of claim 4, wherein said developing means provides spherical toner particles onto said exposed portion of said photoreceptor.
Claim 7
Dependent Claim
15 words
The apparatus of claim 1, wherein said developing means is a non-contact type developing device.
Claim 8
Dependent Claim
19 words
The apparatus of claim 1, wherein said exposure means generates said dot-shaped light by means of pulse width modulation.
Claim 9
Dependent Claim
29 words
The apparatus of claim 1, wherein said charging means, said exposure means and said developing means are actuated in turn repeatedly, thereby superimposing plural toner images on said photoreceptor.
Claim 10
Independent Claim
208 words
An apparatus for forming a toner image by reversal development, comprising: a charging means for uniformly charging a photoreceptor to a given electric potential; said photoreceptor discharging in response to an exposure light to form an electrostatic latent image, said photoreceptor having a predetermined light decay curve representing a relation between an amount of the exposure light and a discharged potential on the exposed portion wherein an absolute value of the differential coefficient of the light decay curve is small when the amount of the exposure light is small and said value sharply becomes large when the amount of the exposure light increases; an exposure means for generating a dot-shaped light by means of pulse width modulation and for exposing said photoreceptor with said dot-shaped light; and a developing means for providing toner onto said exposed portion of said latent image, thereby forming a toner image, wherein said light decay curve satisfies the relationship 1<E 1/2/E 9/10 E 9/10 being a light sensitivity of said photoreceptor when said electrostatic potential has decayed to 9/10 of that at the start of said exposure and E 1/2 is a light sensitivity of said photoreceptor when said electrostatic potential has decayed to 1/2 of that at the start of said exposure.
Claim 11
Independent Claim
208 words
An apparatus for forming a toner image by reversal development, comprising: a charging means for uniformly charging a photoreceptor to a given electric potential; said photoreceptor discharging in response to an exposure light to form an electrostatic latent image, said photoreceptor having a predetermined light decay curve representing a relation between an amount of the exposure light and a discharged potential on the exposed portion wherein an absolute value of the differential coefficient of the light decay curve is small when the amount of the exposure light is small and said value sharply becomes large when the amount of the exposure light increases; an exposure means for generating a dot-shaped light by means of pulse width modulation and for exposing said photoreceptor with said dot-shaped light; and a developing means for providing toner onto said exposed portion of said latent image, thereby forming a toner image, wherein said light decay curve satisfies the relationship 1<E 1/2/E 9/10 E 9/10 being a light sensitivity of said photoreceptor when said electrostatic potential has decayed to 9/10 of that at the start of said exposure and E 1/2 is a light sensitivity of said photoreceptor when said electrostatic potential has decayed to 1/2 of that at the start of said exposure.
Claim 12
Dependent Claim
17 words
The apparatus of claim 9 wherein said light decay curve satisfies the following relation; 2≦(E 1/2)/E 9/10)
Claim 13
Dependent Claim
22 words
The apparatus of claim 9 wherein said photoreceptor includes a photoconductive layer containing semiconductive particles, and wherein said semiconductive particles contain phthalocyanine.
Claim 14
Dependent Claim
22 words
The apparatus of claim 9 wherein said photoreceptor includes a photoconductive layer containing thermosetting resin in which photoconductive semiconductive particles are dispersed.
Claim 15
Dependent Claim
20 words
The apparatus of claim 9 wherein said developing means provides spherical toner particles onto said exposed portion of said photoreceptor.
Claim 16
Dependent Claim
15 words
The apparatus of claim 9 wherein said developing means is a non-contact type developing device.
Claim 17
Independent Claim
221 words
An apparatus for forming a toner image by reversal development, comprising: a charging means for uniformly charging a photoreceptor to a given electric potential; said photoreceptor discharging in response to an exposure light to form an electrostatic latent image, said photoreceptor having a predetermined light decay curve representing a relation between an amount of the exposure light and a discharged potential on the exposed portion wherein an absolute value of the differential coefficient of the light decay curve is small when the amount of the exposure light is small and said value sharply becomes large when the amount of the exposure light increases; an exposure means for exposing said photoreceptor with a dot-shaped light; and a developing means for providing toner onto said exposed portion of said latent image, thereby forming a toner image, wherein said charging means, said exposure means and said developing means are actuated in turn repeatedly, thereby superimposing plural toner images on said photoreceptor, wherein said light decay curve satisfies the relationship < E 1/2/E 9/10 E 9/10 being a light sensitivity of said photoreceptor when said electrostatic potential has decayed to 9/10 of that at the start of said exposure and E 1/2 is a light sensitivity of said photoreceptor when said electrostatic potential has decayed to 1/2 of that at the start o said exposure.
Claim 18
Independent Claim
221 words
An apparatus for forming a toner image by reversal development, comprising: a charging means for uniformly charging a photoreceptor to a given electric potential; said photoreceptor discharging in response to an exposure light to form an electrostatic latent image, said photoreceptor having a predetermined light decay curve representing a relation between an amount of the exposure light and a discharged potential on the exposed portion wherein an absolute value of the differential coefficient of the light decay curve is small when the amount of the exposure light is small and said value sharply becomes large when the amount of the exposure light increases; an exposure means for exposing said photoreceptor with a dot-shaped light; and a developing means for providing toner onto said exposed portion of said latent image, thereby forming a toner image, wherein said charging means, said exposure means and said developing means are actuated in turn repeatedly, thereby superimposing plural toner images on said photoreceptor, wherein said light decay curve satisfies the relationship < E 1/2/E 9/10 E 9/10 being a light sensitivity of said photoreceptor when said electrostatic potential has decayed to 9/10 of that at the start of said exposure and E 1/2 is a light sensitivity of said photoreceptor when said electrostatic potential has decayed to 1/2 of that at the start o said exposure.
Claim 19
Dependent Claim
17 words
The apparatus of claim 14 wherein said light decay curve satisfies the following relation; 2≦(E 1/2)/E 9/10)
Claim 20
Dependent Claim
22 words
The apparatus of claim 15 wherein said photoreceptor includes a photoconductive layer containing semiconductive particles, and wherein said semiconductive particles contain phthalocyanine.
Claim 21
Dependent Claim
22 words
The apparatus of claim 15 wherein said photoreceptor includes a photoconductive layer containing thermosetting resin in which photoconductive semiconductive particles are dispersed.
Claim 22
Dependent Claim
20 words
The apparatus of claim 15 wherein said developing means provides spherical toner particles onto said exposed portion of said photoreceptor.
Claim 23
Dependent Claim
15 words
The apparatus of claim 15 wherein said developing means is a non-contact type developing device.
References Cited (Backward Citations)
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