CA1081523A - Electrophotographic materials containing sublimable dyes - Google Patents
Electrophotographic materials containing sublimable dyesInfo
- Publication number
- CA1081523A CA1081523A CA236,488A CA236488A CA1081523A CA 1081523 A CA1081523 A CA 1081523A CA 236488 A CA236488 A CA 236488A CA 1081523 A CA1081523 A CA 1081523A
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- CA
- Canada
- Prior art keywords
- color
- sublimable
- dye
- producing
- photosensitive element
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
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Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G13/00—Electrographic processes using a charge pattern
- G03G13/01—Electrographic processes using a charge pattern for multicoloured copies
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G5/00—Recording members for original recording by exposure, e.g. to light, to heat, to electrons; Manufacture thereof; Selection of materials therefor
- G03G5/12—Recording members for multicolour processes
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Developing Agents For Electrophotography (AREA)
- Photoreceptors In Electrophotography (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
An electrophotographic process of forming a dye image comprising the steps of:
(1) charging a photosensitive element formed on an electro-conductive support by electrical charging, said photosensitive element consisting essentially of photoconductive particles and sublimable dyes, (2) exposing image-wise the charged photosensitive element to light, (3) developing the photosensitive element with acid toners (4) heating the photosensitive element to sublime the sublimable dyes to form a dye image and (5) transferring the dye image to a dye image-accepting substrate with the aid of a solvent.
An electrophotographic process of forming a dye image comprising the steps of:
(1) charging a photosensitive element formed on an electro-conductive support by electrical charging, said photosensitive element consisting essentially of photoconductive particles and sublimable dyes, (2) exposing image-wise the charged photosensitive element to light, (3) developing the photosensitive element with acid toners (4) heating the photosensitive element to sublime the sublimable dyes to form a dye image and (5) transferring the dye image to a dye image-accepting substrate with the aid of a solvent.
Description
1C3 8~3 BACKGROUND OF THE INVENTION
-An electrophotographic material comprises an electroconduc~ive support and a photosensitive element (i.e.
photoconductive layer2 formed thereon. The principle of an electrophotographic process in the black and white reproduction field is that an electrostatic latent image is formed by image-wise exposure of a charged photosensitive element and the image is then developed by a fine powder, called the toner, which is electrically deposited on the latent image to form a visible black image.
In the present invention, sublimable dyes or sublimable leuco dyes are contained in a photosensitive ~`~
element (a photoconductive layer), and a unicolored dye image or a multicolored dye image is formed on the photo-sensitive element.
SUMMARY OF THE INVENTION
The present invention relates to an electrophoto-graphic process of forming a dye image and electrophoto-graphic materials for use in the electrophotographic process.
~0 An electrophotographic material of this invention has a photosensitive element (i.e. photoconductive layer) on an electroconductive support, said photosensitive ele-ment consisting essentially of photoconductive powders (powders of photoconductors) and sublimable dyes. Said sublimable dyes may be sublimable leuco dyes. This electro-photographic material is used for obtaining a unicolored dye image.
Thus, in accordance with the present teachings, an electrophotographic process of forming a dye image is ,;~
provided which comprises the steps of charging a photosensi-
-An electrophotographic material comprises an electroconduc~ive support and a photosensitive element (i.e.
photoconductive layer2 formed thereon. The principle of an electrophotographic process in the black and white reproduction field is that an electrostatic latent image is formed by image-wise exposure of a charged photosensitive element and the image is then developed by a fine powder, called the toner, which is electrically deposited on the latent image to form a visible black image.
In the present invention, sublimable dyes or sublimable leuco dyes are contained in a photosensitive ~`~
element (a photoconductive layer), and a unicolored dye image or a multicolored dye image is formed on the photo-sensitive element.
SUMMARY OF THE INVENTION
The present invention relates to an electrophoto-graphic process of forming a dye image and electrophoto-graphic materials for use in the electrophotographic process.
~0 An electrophotographic material of this invention has a photosensitive element (i.e. photoconductive layer) on an electroconductive support, said photosensitive ele-ment consisting essentially of photoconductive powders (powders of photoconductors) and sublimable dyes. Said sublimable dyes may be sublimable leuco dyes. This electro-photographic material is used for obtaining a unicolored dye image.
Thus, in accordance with the present teachings, an electrophotographic process of forming a dye image is ,;~
provided which comprises the steps of charging a photosensi-
2 ~
j, , . " . . .
.; , .: , . . . : :- , ,.. :, 81~'~3 tive element formed on an electroconductive support by electrically charging. The photosensitive element consists essentially of photoconductive powders and from 0.5 to 15 by weight based on the amount of photoconductive powders of sublimable dyes. The charged photosensitive element is exposed image-wise to light to form an electrostatic latent image and the photosensitive element is developed employing acidic toners. The photosensitive element is then heated to form a dye image and the dye image transferred to a dye image-accepting substrate with the aid o~ a solvent.
Thus, in accordance with a further aspect of the present teachings, a photosensitive element is provided which comprises three kinds of color-producing photosensitive particles, the color-producing photosensitive particles consisting of:
1) color-producing photosensitive particles consisting essentially of a photoconductive powder, a sensitizer absorbing blue-violet light and a sublimable yellow color dye, 2) color-producing photosensitive particles consisting essentially of a photoconductive powder, a sensitizer absorbing green light and a sublimable magenta color dye, and
j, , . " . . .
.; , .: , . . . : :- , ,.. :, 81~'~3 tive element formed on an electroconductive support by electrically charging. The photosensitive element consists essentially of photoconductive powders and from 0.5 to 15 by weight based on the amount of photoconductive powders of sublimable dyes. The charged photosensitive element is exposed image-wise to light to form an electrostatic latent image and the photosensitive element is developed employing acidic toners. The photosensitive element is then heated to form a dye image and the dye image transferred to a dye image-accepting substrate with the aid o~ a solvent.
Thus, in accordance with a further aspect of the present teachings, a photosensitive element is provided which comprises three kinds of color-producing photosensitive particles, the color-producing photosensitive particles consisting of:
1) color-producing photosensitive particles consisting essentially of a photoconductive powder, a sensitizer absorbing blue-violet light and a sublimable yellow color dye, 2) color-producing photosensitive particles consisting essentially of a photoconductive powder, a sensitizer absorbing green light and a sublimable magenta color dye, and
3) color-producing photosensitive particles consisting essentially of a photoconductive powder, a sensitizer absorbing red light and a sublimable cyan color dye.
Another electrophotographic material of this invention has a photosensitive element (i.e. photoconductive layer) on an electroconductive support, said photosensitive element consisting essentially of photoconductive powders (powders of photoconductors), sensitizers and sublimable dyes.
Said sublimable dyes may be sublimable leuco dyes. This electrophotographic material containing sensitizers is used for obtaining a multicolored dye image.
~ _3_ D
... . .. . . . . . .
108~5~3 An electrophotographic material for forming a uni-col~red dye image may be prepared as follows:
A dispersion is obtained by mixing a photoconductive powder ~powder of photoconductor), a sublimable dye (or a sublimable leuco dye), a binder and an organic solvent in a ball mill. The dispersion is applied to a surface of an ! electroconductive support and dried off.
An electrophotographic material for forming a multi- :
colored dye image may be prepared as follows:
A dispersion is obtained by mixing a photoconductive powder (powder of photoconductor), a sensitizer, a sublimable dye (or a sublimable leuco dye), a binder and an organic solvent.
: . i ''''~,....
,~,.
-3a-~ `;.
15;~3 Three kinds of dispersions for yellow, magenta and cyan colors are prepared by using three kinds of sensitizers -and sublimahle dyes. Three kinds of color-producing photo-sensitive particules having particule size of 10 to 100 microns are obtained by spraying the dispersions under a pressure of nitrogen gas by means of spray gun. A mixture of three kinds of color-producing photosensitive particles are distributed on a surface of a charged polyester film, and electroconductive paper is laid on the surface of the polyester film. The laminated material thus obtained is passed through a calender at an elevated temperature, and then the polyester film ls peeled off from the paper to obtain an electrophotographic material for color process carrying a photosensitive element on the paper.
In this invention, the following photoconductors in powder form may be used: ;
Inorganic photoconductors such as zinc oxide, cadmium sulfide, zinc sulfide and selenium; organic photo- `
conductors such as polyvinylanthracene, 9,10-dimethyl-anthrancene, other anthracene derivatives, N-ethyl- -carbazole, 9,10-dibromo-N-ethylcarbazole, poly-N-vinyl-carbazole, other carbazole derivatives, pyrazolone deriva tives, naphthalene derivatives, pyrene, pyrene derivatives and reaction product of 9,10-dichloromethylanthracene and N-ethylcarbazole.
The following sublimable dyes and sublimable leuco dyes may be used:
Yellor (or orange) color-producing dye:
Sublimable dye: diphenylamine, 1,3-dinitro-3'-hydroxydiphenylamine, 1-amino-2-methylanthraquinone;
Sublimable leuco dye: 4,4'-tetradimethylaminodiphenyl ketone;
~08~5Z3 Magenta color-producing dye:
Sublimable dye: l-amino-2-methoxy-4-hydroxyanthra-quinone, 1,4-diamino-2-methoxyanthraquinone, 3-nitrophenylazo-3'-aminobenzene, 1-methyl-3-amino-4-methoxy-phenylazo-3'-aminobenzene;
Sublimable leuco dye: 3,4,8,9-tetradimethylamino-phenazine.
Cyan (or blue) color-producing dye:
Sublimable dye: Malachite Green, 1,4,5,8-tetra-aminoanthraquinone, 1-methylamino-4-ethanolamino-anthraquinone;
Sublimable leuco dye: 4,4'-dimethylaminodiphenyl-ethylene;
Such sublimable dyes or sublimable leuco dyes are used in an amount of 0.5 to 15%, preferably 1 to 5% by weight, based on the amount of photoconductive powders.
The sensitizers added to the photoconductive powders ~
are as follows: `
Blue sensitizer (sensitizer absorbing blue-violet light):
Uramine, Fluorescein, Tartrazine, 3-carboxymethyl-5-(3-ethyl-2(3)-benzthiazolidene)-rhodanine-triethylamine salt, ;
Auramine and Seto-flavine T.
Green sensitizer (sensitizer absorbing green light):
Rose Bengale, Eosine, Erythrosine, Fuchsine, Pyronine B, Rhodamine G, Violanin, Methyl Violet, Neutral Red and Astrophloxine.
Red Sensitizer (sensitizer absorbing red light):
Diacid Cyanine Green GWA, Methylene Blue, Patent Blue V, Victoria Blue B, Xylene Cyanol FF and srilliant Blue A. ~-Quinones and nitrated quinones also may be used as a sensitizer.
~8~Z3 Such sensitizers are added in an amount of 0.0001 to 2% by weight, preferably 0.002 to 0.2% by weight, based on the amount of photoconductive powders.
As a binder, the following organic high molecular compounds may be used:
Acrylic resin, vinyl chloride resin, vinyl acetate resin, vinyl chloride-vinyl acetate copolymer, styrene-butadiene copolymer, styrene resin, silicone resin, epoxy-silicone resin, alkyd resin, epoxy resin, phenol resin, maleic acid resin and wax.
The binder is used in an amount of 5 to 40% by weight based on the amount of photoconductive powders.
As an organic solvent, the following solvents may be used:
Alcohols such as methanol and ethanol; ketones such as acetones and methyl ethyl ketone; aromatic hydrocarbons such as benzene, toluene and xylene halogenated hydrocarbons such as ethylene chloride and trichloroethylene; and tetrahydrofuran.
As an electroconductive support, high quality paper applied high molecular quaternary ammonium salt, electroconductive plastic film, aluminium-coated paper and metal sheet may be used.
The present invention is based on the principle as described below: ~-(1) Sublimable dyes can be sublimed by heating at a temperature of 80C to 200C.
(2) Sublimable dyes are captured by acid substances.
(3) Sublimable dyes captured by acid substances become difficult to sublime.
Another electrophotographic material of this invention has a photosensitive element (i.e. photoconductive layer) on an electroconductive support, said photosensitive element consisting essentially of photoconductive powders (powders of photoconductors), sensitizers and sublimable dyes.
Said sublimable dyes may be sublimable leuco dyes. This electrophotographic material containing sensitizers is used for obtaining a multicolored dye image.
~ _3_ D
... . .. . . . . . .
108~5~3 An electrophotographic material for forming a uni-col~red dye image may be prepared as follows:
A dispersion is obtained by mixing a photoconductive powder ~powder of photoconductor), a sublimable dye (or a sublimable leuco dye), a binder and an organic solvent in a ball mill. The dispersion is applied to a surface of an ! electroconductive support and dried off.
An electrophotographic material for forming a multi- :
colored dye image may be prepared as follows:
A dispersion is obtained by mixing a photoconductive powder (powder of photoconductor), a sensitizer, a sublimable dye (or a sublimable leuco dye), a binder and an organic solvent.
: . i ''''~,....
,~,.
-3a-~ `;.
15;~3 Three kinds of dispersions for yellow, magenta and cyan colors are prepared by using three kinds of sensitizers -and sublimahle dyes. Three kinds of color-producing photo-sensitive particules having particule size of 10 to 100 microns are obtained by spraying the dispersions under a pressure of nitrogen gas by means of spray gun. A mixture of three kinds of color-producing photosensitive particles are distributed on a surface of a charged polyester film, and electroconductive paper is laid on the surface of the polyester film. The laminated material thus obtained is passed through a calender at an elevated temperature, and then the polyester film ls peeled off from the paper to obtain an electrophotographic material for color process carrying a photosensitive element on the paper.
In this invention, the following photoconductors in powder form may be used: ;
Inorganic photoconductors such as zinc oxide, cadmium sulfide, zinc sulfide and selenium; organic photo- `
conductors such as polyvinylanthracene, 9,10-dimethyl-anthrancene, other anthracene derivatives, N-ethyl- -carbazole, 9,10-dibromo-N-ethylcarbazole, poly-N-vinyl-carbazole, other carbazole derivatives, pyrazolone deriva tives, naphthalene derivatives, pyrene, pyrene derivatives and reaction product of 9,10-dichloromethylanthracene and N-ethylcarbazole.
The following sublimable dyes and sublimable leuco dyes may be used:
Yellor (or orange) color-producing dye:
Sublimable dye: diphenylamine, 1,3-dinitro-3'-hydroxydiphenylamine, 1-amino-2-methylanthraquinone;
Sublimable leuco dye: 4,4'-tetradimethylaminodiphenyl ketone;
~08~5Z3 Magenta color-producing dye:
Sublimable dye: l-amino-2-methoxy-4-hydroxyanthra-quinone, 1,4-diamino-2-methoxyanthraquinone, 3-nitrophenylazo-3'-aminobenzene, 1-methyl-3-amino-4-methoxy-phenylazo-3'-aminobenzene;
Sublimable leuco dye: 3,4,8,9-tetradimethylamino-phenazine.
Cyan (or blue) color-producing dye:
Sublimable dye: Malachite Green, 1,4,5,8-tetra-aminoanthraquinone, 1-methylamino-4-ethanolamino-anthraquinone;
Sublimable leuco dye: 4,4'-dimethylaminodiphenyl-ethylene;
Such sublimable dyes or sublimable leuco dyes are used in an amount of 0.5 to 15%, preferably 1 to 5% by weight, based on the amount of photoconductive powders.
The sensitizers added to the photoconductive powders ~
are as follows: `
Blue sensitizer (sensitizer absorbing blue-violet light):
Uramine, Fluorescein, Tartrazine, 3-carboxymethyl-5-(3-ethyl-2(3)-benzthiazolidene)-rhodanine-triethylamine salt, ;
Auramine and Seto-flavine T.
Green sensitizer (sensitizer absorbing green light):
Rose Bengale, Eosine, Erythrosine, Fuchsine, Pyronine B, Rhodamine G, Violanin, Methyl Violet, Neutral Red and Astrophloxine.
Red Sensitizer (sensitizer absorbing red light):
Diacid Cyanine Green GWA, Methylene Blue, Patent Blue V, Victoria Blue B, Xylene Cyanol FF and srilliant Blue A. ~-Quinones and nitrated quinones also may be used as a sensitizer.
~8~Z3 Such sensitizers are added in an amount of 0.0001 to 2% by weight, preferably 0.002 to 0.2% by weight, based on the amount of photoconductive powders.
As a binder, the following organic high molecular compounds may be used:
Acrylic resin, vinyl chloride resin, vinyl acetate resin, vinyl chloride-vinyl acetate copolymer, styrene-butadiene copolymer, styrene resin, silicone resin, epoxy-silicone resin, alkyd resin, epoxy resin, phenol resin, maleic acid resin and wax.
The binder is used in an amount of 5 to 40% by weight based on the amount of photoconductive powders.
As an organic solvent, the following solvents may be used:
Alcohols such as methanol and ethanol; ketones such as acetones and methyl ethyl ketone; aromatic hydrocarbons such as benzene, toluene and xylene halogenated hydrocarbons such as ethylene chloride and trichloroethylene; and tetrahydrofuran.
As an electroconductive support, high quality paper applied high molecular quaternary ammonium salt, electroconductive plastic film, aluminium-coated paper and metal sheet may be used.
The present invention is based on the principle as described below: ~-(1) Sublimable dyes can be sublimed by heating at a temperature of 80C to 200C.
(2) Sublimable dyes are captured by acid substances.
(3) Sublimable dyes captured by acid substances become difficult to sublime.
(4) Sublimable colorless leuco dyes produce color by con-tacting with acid substances.
~1523 As the acid substance, the following organic acids and inorganic substance may he used:
Oxalic acid, tartaric acid, trichloroacetic acid, citric acid, maleic acid, fumaxic acid, citraconic acid, suberic acid, maleic acid, behenic acid, ascorbic acid, phenylacetic acid, salicylic acid, gallic acid, picric acid, polyparaphenylphenol and activated clay.
Toners and developers which are used in the process of the present invention may be prepared, for example, as follows:
Toners are prepared by pulverizing styrene resins such as polyaminostyrene, dimethylaminostyrene and diethyl-aminostyrene, polyvinylpyrrolidone, alkyd resin, or phenol-formaldehyde resin. Toners containing acid substance may ~
be prepared by mixing with the acid substances as shown -above.
Developers in powder form or liquid form are pre- `~
pared by mixing the toners with iron powders or by dis- `
persing the toners in hydrocarbons. In this way, the ~j;
positively or negatively charged toners can be obtained.
The process of the present invention for forming a unicolored dye image will be illustrated below:
In this case, zinc oxide is used as a photoconductive powder, and as previously described, an electrophotographic material is prepared.
The photosensitive element is negatively charged by conventional electrical charging such as corona discharge and then exposed image-wise to light to form an electrostatic latent image on the photosensitive element. Toners are deposited on the latent image by developing with a developer containing positively charged toners, and then the toners ' ~
~L0~1523 are fixed to the photosensitive element by heating the photosensitive element, for example, at a temperature of 120C.
The process of the present invention for forming a multicolor dye image will be illustrated below:
In this case, zinc oxide is used as a photoconductive powder, and as previously described, an electrophotographic material is prepared.
Three kinds of Color-producing photosensitive particles B, G and R consist of as follows:
Particle s consists of a photoconductive powder, a sensitizer absorbing blue-violet light and a sublimable yellow color dye. A sublimable leuco dye producing yellow color may be used instead of the sublimable yellow color dye.
Particle G consists of a photoconductive powder, a sensitizer absorbing green light and a sublimable magenta color dye.
A sublimable leuco dye producing magenta color may be used instead of the sublimable magenta color dye.
Particle R consists of a photoconductive powder, a sensitizer ~0 absorbing red light and a sublimable cyan color dye. A
sublimable leuco dye producing cyan color may be used in-stead of the sublimable cyan color dye.
When color-producing photosensitive particles B, G and R are charged by corona discharge and exposed to light, particles B, G and R, respectively, absorb blue-violet, green and red lights to dissipate the electric charge.
On referring to the accompanying drawings, Figure l, an electrophotographic material comprises an electro-conductive support and a photosensitive element (a photo-conductive layer) formed on the support, the photosensitive element consisting of Color-producing photosensitive particles .. . ~ , . .
- . . : . . . .
lS23 B, G and R disposed at random on the support. When the photosensitive element is negatively charged by corona discharge and then exposed to blue-violet, green and red lights, electrical charges of Particles B, G and R dissipate or remain as follows and electrostatic latent images are formed on the photosensitive element:
In the region (B) irradiated by blue-violet light, electric charge of Particle B dissipates and electric charges of Particles G and R remain. -In the region (G) irradiated by green light, electric charge of Particle G dissipates and electric charges of `
Particles B and R remain.
In the region (R) irradiated by red light, electric charge of Particle R dissipates and electric charges of Particles B and G remain.
In the non-irradiated region, all electric charges of Particles B, G and R remain.
In the region irradiated by white light, all electric charges of Particles B, G and R dissipate.
Toners are deposited on the latent image by develop-ing with a developer containing positively charged toners as follows:
In the region irradiated by blue-violet light, toners are deposited on Particles G and R. In the region irradiated by green light, toners are deposited on Particles B and R. -`
In the region irradiated by red light, toners are deposited on Particles B and G. In the non-irradiated region, toners are deposited on Particles B, G and R.
The toners are fixed to Particles B, G or R by heating the photosensitive element, for example, at a temperature of 120C.
1~8~iZ3 A positive-to-positive color dye image is formed on the photosensitive element. secause, magenta color dye in Particle G and cyan color dye in Particle R pro-duce blue color; yellow color dye in Particle B and cyan color dye in Particle R produce green color; and yellow ;}
color dye in Particle B and magenta color dye in Particle G produce red color.
A positive-to-positive or a positive-to-negative dye images can be obtained on a support by repeating the same procedure as that described above except that sub-limable leuco dyes and toners containing acid substance are used. Such dye images can be transferred to a substrate such as paper as follows:
On referrlng to Figure 2, the positive-to-positive color image obtained above can be transferred to a surface of paper with the aid of solvent such as water or organic solvents. For example, paper wetted by water is laid on the photosensitive element having the dye image formed and -;~then the paper is peeled off from the photosensitive element.
Said organic solvents include alcohols such as `
methyl alcohol and ethyl alcohol, ketone such as acetone ;-and methyl ethyl ketone, tetrahydrofuran and other hydro-carbons.
In the above, the present inventions has been illustrated by using three kinds of color-producing photo-sensitive particles. However, it is understood that two-kinds of color-producing photosensitive particles may optionally be used.
Further, a combination of a sensitizer and a sub-limable dye may optionally be selected to obtain colors other than those as shown above.
- lo .. ..
- .. ... .. - .. . ;; .. ... . . . . . :
~08~S23 DESCRIPTION OF_THE PREFERRED EMBODIMENTS:
The following examples are given by way of illustra-tion only and are not intended as limitation of this inven-tion.
Example 1 -A dispersion was prepared by mixing 200g of zinc oxide, 6g of 1-amino-2-methylanthraquinone (sublimable yellow dye), 30g of acrylic resin and 200g of toluene in a ball mill. The dispersion was applied to a surface of an aluminium ~ilm of an aluminium-coated paper by means of wire bar to obtain an electrophotographic material having a photosensitive element of 15 microns in thickness.
Polyaminostyrene was pulverized to obtain fine ~;
powders (tonersl having particle size of about 5 microns.
The powders (powdered polyaminostyrene) were mixed with iron powders to obtain a developer in powder form. The `
toners were positively charged.
The electrophotographic material obtained above ;`
was negatively charged using a conventional corona discharge of -6kV and it was then exposed to light whilst in contact with an image original, and it was developed with the developer prepared above by using magnetic brush. The ;~
toners were fixed to the image area of the photosensitive element by heating at a temperature of 120C to form a positive-to-positive white image on the photosensitive element. Paper carrying activated clay was laid on the ~;
photosensitive element and then the photosensitive element was heated at a temperature of 170C for 30 second.
positive-to-negative reversed yellow dye image was formed on the paper by sublimation of 1-amino-2-methylanthra-quinone.
.
. , : . ,:. ,::
315~3 Example 2 ;~
Phenol-formaldehyde resin (sold by Araka~a Rinsan Kagakukogyo K.K. under the trademark of Tamanal PA) was pulverized to obtain fine powders (toners) having particle size of about 5 microns. The powders were mixed with hydrocarbon ~sold by Shell Chemicals Co. under the trade-mark sopar H) and then dispersed in a ball mill to obtain a dispersion containing the powders having particle~size of about one micron. The powders were negatively charged.
The same procedure as that of Example 1 was repeated b~ utilizing an electrophotographic material prepared in Example 1 except that the dispersion obtained above was used as a developer instead of the developer prepared in Example 1. The toners were deposited in the non-image area of the photosensitive element to form a ;
positive-to-negative white image. ~`
A positive-to-positive reversed yellow dye image ~;
was formed on the paper carrying activated clay by repeat-ing the procedure as shown in Example 1.
Example 3 A mixture of 300g of tartaric acid and 150g of polyparadimethylaminostyrene was dissolved in 500g of '~
methanol. After the solution obtained was dried up, the residue was pulverized by a jet mill to obtain fine powders (toners) having particle size of about 5 microns. The powders were mixed with iron powders to obtain a developer in powder form. The toners were positively charged.
The same procedure as that of Example 1 was re-peated by utilizing an electrophotographic material prepared in Example 1 except that the developer obtained above and ~08~5Z3 phenol resin (polyparaphenylphenol resin)-coated paper were used instead of the developer prepared in Example 1 and paper carrying activated clay. ;~
A positive-to-negative yellow dye image similar to that of Example 1 was formed on the paper.
Example 4 A dispersion was prepared by mixing 200g æinc oxide, 7g of bis (4,4'-di-paradimethylaminodiphenyl ethylene and -~
200g of toluene in a ball mill. The dispersion was applied ~ ~
to a surface of an aluminium film of an aluminium-coated - ;paper to obtain an electrophotographic material having a photosensitive element of 15 microns in thickness.
The photosensitive element was charged and exposed ;
as described in Example 1 and then developed by using the developer prepared in Example 3 and heated at a temperature `
of 130C for 30 seconds. In this way, a positive-to-positive `-cyan-color dye image was formed on the photosensitive ele-ment.
A dye image-accepting substrate was prepared by . .
applying a mixture of 400g of titanium oxide, 30g of gelatin, 600g of water and 5g of formaldehyde to a surface of white paper and drying so as to have a surface layer of about 10 microns in thickness. The substrate which has been wetted by water, was laid on the photosensitive element carrying the cyan-color dye image. The cyan-color dye image was transferred from the photosensitive element to the substrate.
The substrate carrying a positive-to-positive reversed cyan-color dye image was obtained.
Example 5 , A suspension was prepared by mixing 600g of zinc -oxide, 90g of acrylic resin and 600g of toluene ln a ball ~L~8:1523 ~.
mill. The suspension was divided into three parts. Dis-persions B, G and R were prepared by mixing a sensitizer and a sublimable dye with the suspension as follows:
Dispersion B:
Auramine (blue sensitizer~ 0.02g 1,3-dinitro-3'-hydroxydiphenylamine 5g (sublimable yellow color dye) Suspension prepared above 430g Dispersion G:
Rose Bengale (green sensitizer) 0.005g -3-nitrophenylazo-3'-aminobenzene 6g (sublimable magenta color dye) (~`
Suspension prepared above 430g Dispersion R:
Crystal Violet (red sensitizer) 0.03g Malachite Green 4g (sublimable cyan color dye) Suspension prepared above 430g Color-producing photosensitive particles s, G and R
having particle size of 30 to 44 microns were obtained by spraying Dispersion B, G and R under a pressure of 2kg/cm2 of nitrogen gas by means of spray gun in an atmosphere having a temperature of 25C, respectively. A mixture of Particles B, G and R was distributed on a surface of a charged poly- ~`
ester film, and electroconductive paper having a thickness of 70 microns was laid on the surface of the polyester film.
The laminated material thus obtained was passed through a calender at a temperature of 70C and a pressure of 7kg/cm, and then the polyester film was peeled off from the paper to obtain an electrophotographic material (A) for color process carrying a photosensitive element on the paper.
-- 1~ -- .
.
~- ~0~523 Properties of Electrophotographic material (A) are shown below:
Acceptance potent~al (Vo): -350V
Retentivity after 60 seconds 60%
(V60/Vo X 100) Photographic sensitivity (Elo):100 lux.sec Elo: The exposure required to reduce the surface electric potential to one tenth of its original value. -The electrophotographic material (A) obtained above was negatively charged using a conventional corona dis- `
charge of -6kV and then it was exposed to light whilst in ;~
contact with an color (blue, green and red) image original, and it was developed with the developer prepared in Example 1 by using magnetic brush. The toners were fixed to the image area of the photosensitive element by heating at a -~
temperature of 120C to form a positive white image on the ;
photosensitive element. Paper (B) carrying activated clay was laid on the photosensitive element and then the photo- ;
sensitive element was heated at a temperature of 170C for 30 seconds. In this way, a positive-to-negative reversed dye image having complementary colors (yellow, magenta and cyan) was formed on the paper (B).
Example 6 Electrophotographic material (A) prepared in Example
~1523 As the acid substance, the following organic acids and inorganic substance may he used:
Oxalic acid, tartaric acid, trichloroacetic acid, citric acid, maleic acid, fumaxic acid, citraconic acid, suberic acid, maleic acid, behenic acid, ascorbic acid, phenylacetic acid, salicylic acid, gallic acid, picric acid, polyparaphenylphenol and activated clay.
Toners and developers which are used in the process of the present invention may be prepared, for example, as follows:
Toners are prepared by pulverizing styrene resins such as polyaminostyrene, dimethylaminostyrene and diethyl-aminostyrene, polyvinylpyrrolidone, alkyd resin, or phenol-formaldehyde resin. Toners containing acid substance may ~
be prepared by mixing with the acid substances as shown -above.
Developers in powder form or liquid form are pre- `~
pared by mixing the toners with iron powders or by dis- `
persing the toners in hydrocarbons. In this way, the ~j;
positively or negatively charged toners can be obtained.
The process of the present invention for forming a unicolored dye image will be illustrated below:
In this case, zinc oxide is used as a photoconductive powder, and as previously described, an electrophotographic material is prepared.
The photosensitive element is negatively charged by conventional electrical charging such as corona discharge and then exposed image-wise to light to form an electrostatic latent image on the photosensitive element. Toners are deposited on the latent image by developing with a developer containing positively charged toners, and then the toners ' ~
~L0~1523 are fixed to the photosensitive element by heating the photosensitive element, for example, at a temperature of 120C.
The process of the present invention for forming a multicolor dye image will be illustrated below:
In this case, zinc oxide is used as a photoconductive powder, and as previously described, an electrophotographic material is prepared.
Three kinds of Color-producing photosensitive particles B, G and R consist of as follows:
Particle s consists of a photoconductive powder, a sensitizer absorbing blue-violet light and a sublimable yellow color dye. A sublimable leuco dye producing yellow color may be used instead of the sublimable yellow color dye.
Particle G consists of a photoconductive powder, a sensitizer absorbing green light and a sublimable magenta color dye.
A sublimable leuco dye producing magenta color may be used instead of the sublimable magenta color dye.
Particle R consists of a photoconductive powder, a sensitizer ~0 absorbing red light and a sublimable cyan color dye. A
sublimable leuco dye producing cyan color may be used in-stead of the sublimable cyan color dye.
When color-producing photosensitive particles B, G and R are charged by corona discharge and exposed to light, particles B, G and R, respectively, absorb blue-violet, green and red lights to dissipate the electric charge.
On referring to the accompanying drawings, Figure l, an electrophotographic material comprises an electro-conductive support and a photosensitive element (a photo-conductive layer) formed on the support, the photosensitive element consisting of Color-producing photosensitive particles .. . ~ , . .
- . . : . . . .
lS23 B, G and R disposed at random on the support. When the photosensitive element is negatively charged by corona discharge and then exposed to blue-violet, green and red lights, electrical charges of Particles B, G and R dissipate or remain as follows and electrostatic latent images are formed on the photosensitive element:
In the region (B) irradiated by blue-violet light, electric charge of Particle B dissipates and electric charges of Particles G and R remain. -In the region (G) irradiated by green light, electric charge of Particle G dissipates and electric charges of `
Particles B and R remain.
In the region (R) irradiated by red light, electric charge of Particle R dissipates and electric charges of Particles B and G remain.
In the non-irradiated region, all electric charges of Particles B, G and R remain.
In the region irradiated by white light, all electric charges of Particles B, G and R dissipate.
Toners are deposited on the latent image by develop-ing with a developer containing positively charged toners as follows:
In the region irradiated by blue-violet light, toners are deposited on Particles G and R. In the region irradiated by green light, toners are deposited on Particles B and R. -`
In the region irradiated by red light, toners are deposited on Particles B and G. In the non-irradiated region, toners are deposited on Particles B, G and R.
The toners are fixed to Particles B, G or R by heating the photosensitive element, for example, at a temperature of 120C.
1~8~iZ3 A positive-to-positive color dye image is formed on the photosensitive element. secause, magenta color dye in Particle G and cyan color dye in Particle R pro-duce blue color; yellow color dye in Particle B and cyan color dye in Particle R produce green color; and yellow ;}
color dye in Particle B and magenta color dye in Particle G produce red color.
A positive-to-positive or a positive-to-negative dye images can be obtained on a support by repeating the same procedure as that described above except that sub-limable leuco dyes and toners containing acid substance are used. Such dye images can be transferred to a substrate such as paper as follows:
On referrlng to Figure 2, the positive-to-positive color image obtained above can be transferred to a surface of paper with the aid of solvent such as water or organic solvents. For example, paper wetted by water is laid on the photosensitive element having the dye image formed and -;~then the paper is peeled off from the photosensitive element.
Said organic solvents include alcohols such as `
methyl alcohol and ethyl alcohol, ketone such as acetone ;-and methyl ethyl ketone, tetrahydrofuran and other hydro-carbons.
In the above, the present inventions has been illustrated by using three kinds of color-producing photo-sensitive particles. However, it is understood that two-kinds of color-producing photosensitive particles may optionally be used.
Further, a combination of a sensitizer and a sub-limable dye may optionally be selected to obtain colors other than those as shown above.
- lo .. ..
- .. ... .. - .. . ;; .. ... . . . . . :
~08~S23 DESCRIPTION OF_THE PREFERRED EMBODIMENTS:
The following examples are given by way of illustra-tion only and are not intended as limitation of this inven-tion.
Example 1 -A dispersion was prepared by mixing 200g of zinc oxide, 6g of 1-amino-2-methylanthraquinone (sublimable yellow dye), 30g of acrylic resin and 200g of toluene in a ball mill. The dispersion was applied to a surface of an aluminium ~ilm of an aluminium-coated paper by means of wire bar to obtain an electrophotographic material having a photosensitive element of 15 microns in thickness.
Polyaminostyrene was pulverized to obtain fine ~;
powders (tonersl having particle size of about 5 microns.
The powders (powdered polyaminostyrene) were mixed with iron powders to obtain a developer in powder form. The `
toners were positively charged.
The electrophotographic material obtained above ;`
was negatively charged using a conventional corona discharge of -6kV and it was then exposed to light whilst in contact with an image original, and it was developed with the developer prepared above by using magnetic brush. The ;~
toners were fixed to the image area of the photosensitive element by heating at a temperature of 120C to form a positive-to-positive white image on the photosensitive element. Paper carrying activated clay was laid on the ~;
photosensitive element and then the photosensitive element was heated at a temperature of 170C for 30 second.
positive-to-negative reversed yellow dye image was formed on the paper by sublimation of 1-amino-2-methylanthra-quinone.
.
. , : . ,:. ,::
315~3 Example 2 ;~
Phenol-formaldehyde resin (sold by Araka~a Rinsan Kagakukogyo K.K. under the trademark of Tamanal PA) was pulverized to obtain fine powders (toners) having particle size of about 5 microns. The powders were mixed with hydrocarbon ~sold by Shell Chemicals Co. under the trade-mark sopar H) and then dispersed in a ball mill to obtain a dispersion containing the powders having particle~size of about one micron. The powders were negatively charged.
The same procedure as that of Example 1 was repeated b~ utilizing an electrophotographic material prepared in Example 1 except that the dispersion obtained above was used as a developer instead of the developer prepared in Example 1. The toners were deposited in the non-image area of the photosensitive element to form a ;
positive-to-negative white image. ~`
A positive-to-positive reversed yellow dye image ~;
was formed on the paper carrying activated clay by repeat-ing the procedure as shown in Example 1.
Example 3 A mixture of 300g of tartaric acid and 150g of polyparadimethylaminostyrene was dissolved in 500g of '~
methanol. After the solution obtained was dried up, the residue was pulverized by a jet mill to obtain fine powders (toners) having particle size of about 5 microns. The powders were mixed with iron powders to obtain a developer in powder form. The toners were positively charged.
The same procedure as that of Example 1 was re-peated by utilizing an electrophotographic material prepared in Example 1 except that the developer obtained above and ~08~5Z3 phenol resin (polyparaphenylphenol resin)-coated paper were used instead of the developer prepared in Example 1 and paper carrying activated clay. ;~
A positive-to-negative yellow dye image similar to that of Example 1 was formed on the paper.
Example 4 A dispersion was prepared by mixing 200g æinc oxide, 7g of bis (4,4'-di-paradimethylaminodiphenyl ethylene and -~
200g of toluene in a ball mill. The dispersion was applied ~ ~
to a surface of an aluminium film of an aluminium-coated - ;paper to obtain an electrophotographic material having a photosensitive element of 15 microns in thickness.
The photosensitive element was charged and exposed ;
as described in Example 1 and then developed by using the developer prepared in Example 3 and heated at a temperature `
of 130C for 30 seconds. In this way, a positive-to-positive `-cyan-color dye image was formed on the photosensitive ele-ment.
A dye image-accepting substrate was prepared by . .
applying a mixture of 400g of titanium oxide, 30g of gelatin, 600g of water and 5g of formaldehyde to a surface of white paper and drying so as to have a surface layer of about 10 microns in thickness. The substrate which has been wetted by water, was laid on the photosensitive element carrying the cyan-color dye image. The cyan-color dye image was transferred from the photosensitive element to the substrate.
The substrate carrying a positive-to-positive reversed cyan-color dye image was obtained.
Example 5 , A suspension was prepared by mixing 600g of zinc -oxide, 90g of acrylic resin and 600g of toluene ln a ball ~L~8:1523 ~.
mill. The suspension was divided into three parts. Dis-persions B, G and R were prepared by mixing a sensitizer and a sublimable dye with the suspension as follows:
Dispersion B:
Auramine (blue sensitizer~ 0.02g 1,3-dinitro-3'-hydroxydiphenylamine 5g (sublimable yellow color dye) Suspension prepared above 430g Dispersion G:
Rose Bengale (green sensitizer) 0.005g -3-nitrophenylazo-3'-aminobenzene 6g (sublimable magenta color dye) (~`
Suspension prepared above 430g Dispersion R:
Crystal Violet (red sensitizer) 0.03g Malachite Green 4g (sublimable cyan color dye) Suspension prepared above 430g Color-producing photosensitive particles s, G and R
having particle size of 30 to 44 microns were obtained by spraying Dispersion B, G and R under a pressure of 2kg/cm2 of nitrogen gas by means of spray gun in an atmosphere having a temperature of 25C, respectively. A mixture of Particles B, G and R was distributed on a surface of a charged poly- ~`
ester film, and electroconductive paper having a thickness of 70 microns was laid on the surface of the polyester film.
The laminated material thus obtained was passed through a calender at a temperature of 70C and a pressure of 7kg/cm, and then the polyester film was peeled off from the paper to obtain an electrophotographic material (A) for color process carrying a photosensitive element on the paper.
-- 1~ -- .
.
~- ~0~523 Properties of Electrophotographic material (A) are shown below:
Acceptance potent~al (Vo): -350V
Retentivity after 60 seconds 60%
(V60/Vo X 100) Photographic sensitivity (Elo):100 lux.sec Elo: The exposure required to reduce the surface electric potential to one tenth of its original value. -The electrophotographic material (A) obtained above was negatively charged using a conventional corona dis- `
charge of -6kV and then it was exposed to light whilst in ;~
contact with an color (blue, green and red) image original, and it was developed with the developer prepared in Example 1 by using magnetic brush. The toners were fixed to the image area of the photosensitive element by heating at a -~
temperature of 120C to form a positive white image on the ;
photosensitive element. Paper (B) carrying activated clay was laid on the photosensitive element and then the photo- ;
sensitive element was heated at a temperature of 170C for 30 seconds. In this way, a positive-to-negative reversed dye image having complementary colors (yellow, magenta and cyan) was formed on the paper (B).
Example 6 Electrophotographic material (A) prepared in Example
5 was developed by repeating the same procedure as that of Example 5 except that the developer prepared in Example 2 !;
was used instead of the developer prepared in Example 1.
As shown in Example 5, paper (B) carrying activated clay was laid on the photosensitive element and the photosensitive element was heated. A positive to-positive reversed color image was formed on the paper (B).
Example 7 Electrophotographic material (~) prepared in Example 5 was developed by repeating the same procedure as that of Example 5 except that the developer prepared in Example 3 was used instead of the developer prepared in Example 1.
Phenol resin-coated paper prepared in Example 3 was laid on the photosensitive element and then the photosensitive element was heated as shown in Example 3. A positive-to-negative reversed image having complementary colors was formed on the paper.
Example 8 Electrophotographic material (A) prepared in Example 5 was developed by repeating the same procedure as that of Example 5 except that the developer prepared in Example 3 was used instead of the developer prepared in Example 1, and then heated at a temperature of 130C for 30 seconds to form a positive-to-positive color image on the light-sensitive material. This color image was transferred to the dye image-accepting substrate prepared in Example 4 by repeating the same procedure as described in Example 4. In this way, a positive-to-positive reversed color image was formed on the substrate.
Example 9 A suspension was prepared by mixing 1200g of zinc oxide, 120g of acrylic resin and lOOOg of toluene in a ball mill. The suspension was divided into three parts.
Dispersions Bl, Gl and Rl were prepared by mixing a sensitizer and a sublimable leuco dye with the suspension as follows:
~C~81523 Dispersion B :
Auramine (blue sensitizer) 0.04g 4,4'-tetradimethylaminodiphenyl ketone 12g (sublimable leuco dye producing yellow color) Suspension prepared above 770g Dispersion Gl:
Rose sengale (green sensitizer) O.Olg 3,4,8,9-tetradimethylaminophenazine 12g (sublimable leuco dye producing magenta color) Suspension prepared above 770g Dispersion Rl:
Diacid Cyanine Green GWA (red 0.06g sensitizer) ~;
4,4'-dimethylaminodiphenylethylene 12g (sublimable leuco dye producing cyan `
color) Suspension prepared above 770g :
: ,.
Color-producing photosensitive particles Bl, G
and Rl having particle size of 30 to 44 microns were ob-tained by spraying Dispersion Bl, Gl and Rl under a pressure ~ ~
of 2kg/cm of nitrogen gas by means of spray gun in an - .
atmosphere of a temperature of 25C, respectively. A mixture of Particles Bl, Gl and Rl was distributed on a surface of a charged polyester film, and electroconductive paper having i a thickness of 70 microns was laid on the surface of the polyester film. The laminated material thus obtained was passed through a calender at a temperature of 70C and a pressure of 7kg/cm, and then the polyester film was peeled off from the paper to obtain an electrophotographic material (Al) for color process carrying a photo-sensitive element on the paper.
Properties of Electrophotographic material Al are shown below:
~cceptance potential (Vo~: -350V
Retentivity after 60 seconds: 70 (V60/Vo x 100~
Photographic sensitivity (Elo): 80 lux.sec The electrophotographic material (Al) obtained above was negatively charged using a conventional corona discharge of -6kV and then it was exposed to light whilst in contact with a color (blue, green and red) image original, and it was developed with the developer prepared in Example 3 and heated at a temperature of 130C for 30 seconds to fix the toners to the image area of the photosensitive element.
In this way, a positive-to-positive color dye image was ~ormed on the photosensitive element.
After heating the photosensitive element at a tem-perature of 130C as shown above, a dye image-accepting substrate prepared in Example 3 was laid on the photosensi-tive element and then the photosensitive element was heated at a temperature of 170C for 30 second. In this way, a positive-to-negative reversed color dye image having -complementary colors (yellow, magenta and cyan) was formed ;
on the substrate. !`,.
Further, after heating the photosensitive element at a temperature of 130C as shown above, a dye image-accepting substrate prepared in Example 4 was laid on the photosensitive element carrying a positive-to-positive color image, as shown in Example 4. The positive-to~positive color dye image was transferred from the photosensitive element to the substrate. The substrate carrying a posltive-to-positive reversed color image was obtained.
11~8~5Z~
Example 10 After an electrophotographic material (Al) prepared in Example 9 was charged and exposed to light as described in Example 9, it was developed with the developer prepared in Example 1 and heated at a temperature of 120C to fix the toners to the image area of the photosensitive element.
Paper carrying activated clay prepared in Example 1 was laid on the photosensitive element, and then the photosensitive element was heated at a temperature of 170C for 30 seconds.
A positive-to-negative reversed image having complementary colors (yellow, magenta and cyan) was formed on the paper.
Example 11 After an electrophotographic material (Al) prepared in Example 9 was charged and exposed to light as described in Example 9, it was developed with the developer prepared in Example 2. The toners were deposited in the non-image area of the photosensitive element to form a positive-to-negative white image.
A positive-to-positive reversed color image was `~
:....' : .
~0 formed on the paper carrying activated clay by repeating ;
the procedure as shown in Example 10.
. "
-- 19 -- ::
was used instead of the developer prepared in Example 1.
As shown in Example 5, paper (B) carrying activated clay was laid on the photosensitive element and the photosensitive element was heated. A positive to-positive reversed color image was formed on the paper (B).
Example 7 Electrophotographic material (~) prepared in Example 5 was developed by repeating the same procedure as that of Example 5 except that the developer prepared in Example 3 was used instead of the developer prepared in Example 1.
Phenol resin-coated paper prepared in Example 3 was laid on the photosensitive element and then the photosensitive element was heated as shown in Example 3. A positive-to-negative reversed image having complementary colors was formed on the paper.
Example 8 Electrophotographic material (A) prepared in Example 5 was developed by repeating the same procedure as that of Example 5 except that the developer prepared in Example 3 was used instead of the developer prepared in Example 1, and then heated at a temperature of 130C for 30 seconds to form a positive-to-positive color image on the light-sensitive material. This color image was transferred to the dye image-accepting substrate prepared in Example 4 by repeating the same procedure as described in Example 4. In this way, a positive-to-positive reversed color image was formed on the substrate.
Example 9 A suspension was prepared by mixing 1200g of zinc oxide, 120g of acrylic resin and lOOOg of toluene in a ball mill. The suspension was divided into three parts.
Dispersions Bl, Gl and Rl were prepared by mixing a sensitizer and a sublimable leuco dye with the suspension as follows:
~C~81523 Dispersion B :
Auramine (blue sensitizer) 0.04g 4,4'-tetradimethylaminodiphenyl ketone 12g (sublimable leuco dye producing yellow color) Suspension prepared above 770g Dispersion Gl:
Rose sengale (green sensitizer) O.Olg 3,4,8,9-tetradimethylaminophenazine 12g (sublimable leuco dye producing magenta color) Suspension prepared above 770g Dispersion Rl:
Diacid Cyanine Green GWA (red 0.06g sensitizer) ~;
4,4'-dimethylaminodiphenylethylene 12g (sublimable leuco dye producing cyan `
color) Suspension prepared above 770g :
: ,.
Color-producing photosensitive particles Bl, G
and Rl having particle size of 30 to 44 microns were ob-tained by spraying Dispersion Bl, Gl and Rl under a pressure ~ ~
of 2kg/cm of nitrogen gas by means of spray gun in an - .
atmosphere of a temperature of 25C, respectively. A mixture of Particles Bl, Gl and Rl was distributed on a surface of a charged polyester film, and electroconductive paper having i a thickness of 70 microns was laid on the surface of the polyester film. The laminated material thus obtained was passed through a calender at a temperature of 70C and a pressure of 7kg/cm, and then the polyester film was peeled off from the paper to obtain an electrophotographic material (Al) for color process carrying a photo-sensitive element on the paper.
Properties of Electrophotographic material Al are shown below:
~cceptance potential (Vo~: -350V
Retentivity after 60 seconds: 70 (V60/Vo x 100~
Photographic sensitivity (Elo): 80 lux.sec The electrophotographic material (Al) obtained above was negatively charged using a conventional corona discharge of -6kV and then it was exposed to light whilst in contact with a color (blue, green and red) image original, and it was developed with the developer prepared in Example 3 and heated at a temperature of 130C for 30 seconds to fix the toners to the image area of the photosensitive element.
In this way, a positive-to-positive color dye image was ~ormed on the photosensitive element.
After heating the photosensitive element at a tem-perature of 130C as shown above, a dye image-accepting substrate prepared in Example 3 was laid on the photosensi-tive element and then the photosensitive element was heated at a temperature of 170C for 30 second. In this way, a positive-to-negative reversed color dye image having -complementary colors (yellow, magenta and cyan) was formed ;
on the substrate. !`,.
Further, after heating the photosensitive element at a temperature of 130C as shown above, a dye image-accepting substrate prepared in Example 4 was laid on the photosensitive element carrying a positive-to-positive color image, as shown in Example 4. The positive-to~positive color dye image was transferred from the photosensitive element to the substrate. The substrate carrying a posltive-to-positive reversed color image was obtained.
11~8~5Z~
Example 10 After an electrophotographic material (Al) prepared in Example 9 was charged and exposed to light as described in Example 9, it was developed with the developer prepared in Example 1 and heated at a temperature of 120C to fix the toners to the image area of the photosensitive element.
Paper carrying activated clay prepared in Example 1 was laid on the photosensitive element, and then the photosensitive element was heated at a temperature of 170C for 30 seconds.
A positive-to-negative reversed image having complementary colors (yellow, magenta and cyan) was formed on the paper.
Example 11 After an electrophotographic material (Al) prepared in Example 9 was charged and exposed to light as described in Example 9, it was developed with the developer prepared in Example 2. The toners were deposited in the non-image area of the photosensitive element to form a positive-to-negative white image.
A positive-to-positive reversed color image was `~
:....' : .
~0 formed on the paper carrying activated clay by repeating ;
the procedure as shown in Example 10.
. "
-- 19 -- ::
Claims (9)
1. An electrophotographic process of forming a dye image comprising the steps of: (1) charging a photosensitive element formed on an electroconductive support by electrical charging, said photosensitive element consisting essentially of photoconductive powders and from 0.5 to 15% by weight based on the amount of photoconductive powders of sublimable dyes, (2) exposing image-wise the charged photosensitive element to light to form an electrostatic latent image, (3) developing the photosensitive element with acidic toners, (4) heating the photosensitive element to form a dye image and (5) transferring the dye image to a dye image-accepting substrate with the aid of a solvent.
2. An electrophotographic process according to claim 1 wherein sublimable dyes are sublimable leuco dyes.
3. An electrophotographic process according to claim 1 wherein the dye image-accepting substrate contains solvents which can dissolve the dye.
4. An electrophotographic process according to claim 3 wherein the solvents include water or solvents soluble in water.
5. An electrophotographic process according to claim 1 wherein the photosensitive element comprises at least two kinds of color-producing photosensitive particles, said color-producing photosensitive particles consisting essential-ly of photoconductive powders, sensitizers and sublimable dyes.
6. An electrophotographic process according to claim 1 wherein the photosensitive element comprises three kinds of color-producing photosensitive particles, said color-producing photosensitive particles consisting of:
(1) color-producing photosensitive particle consisting essentially of a photoconductive powder, a sensitizer absorbing blue-violet light and a sublimable yellow color dye, (2) color-producing photosensitive particle consisting essentially of a photoconductive powder, a sensitizer absorbing green light and a sublimable magenta color dye, and (3) color-producing photosensitive particle consisting essentially of a photoconductive powder, a sensitizer absorbing red light and a sublimable cyan color dye.
(1) color-producing photosensitive particle consisting essentially of a photoconductive powder, a sensitizer absorbing blue-violet light and a sublimable yellow color dye, (2) color-producing photosensitive particle consisting essentially of a photoconductive powder, a sensitizer absorbing green light and a sublimable magenta color dye, and (3) color-producing photosensitive particle consisting essentially of a photoconductive powder, a sensitizer absorbing red light and a sublimable cyan color dye.
7. An electrophotographic process according to claim 6 wherein said sublimable dyes are sublimate leuco dyes, said sublimable leuco dyes being (1) a sublimable leuco dye producing yellow color, (2) a sublimable leuco dye producing magenta color, and (3) a sublimable leuco dye producing cyan color.
8. A photosensitive element which comprises three kinds of color-producing photosensitive particles, said color-producing photosensitive particles consisting of;
(1) color-producing photosensitive particles consisting es-sentially of a photoconductive powder, a sensitizer absorbing blue-violet light and a sublimable yellow color dye, (2) color-producing photosensitive particle consisting essentially of a photoconductive powder, a sensitizer absorbing green light and a sublimable magenta color dye, and (3) color-producing photosensitive particle consisting es-sentially of a photoconductive powder, a sensitizer absorb-ing red light and a sublimable cyan color dye.
(1) color-producing photosensitive particles consisting es-sentially of a photoconductive powder, a sensitizer absorbing blue-violet light and a sublimable yellow color dye, (2) color-producing photosensitive particle consisting essentially of a photoconductive powder, a sensitizer absorbing green light and a sublimable magenta color dye, and (3) color-producing photosensitive particle consisting es-sentially of a photoconductive powder, a sensitizer absorb-ing red light and a sublimable cyan color dye.
9. The element according to claim 8 wherein the sublimable dyes are sublimable leuco dyes, said sublimable leuco dyes being;
(1) a sublimable leuco dye producing yellow color, (2) a sublimable leuco dye producing magenta color, and (3) a sublimable leuco dye producing cyan color.
(1) a sublimable leuco dye producing yellow color, (2) a sublimable leuco dye producing magenta color, and (3) a sublimable leuco dye producing cyan color.
Applications Claiming Priority (6)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11195874A JPS5524100B2 (en) | 1974-09-28 | 1974-09-28 | |
| JP111957/1974 | 1974-09-28 | ||
| JP111958/L974 | 1974-09-28 | ||
| JP49111957A JPS5139045A (en) | 1974-09-28 | 1974-09-28 | Karaagazokeiseihoho |
| JP50066831A JPS51142329A (en) | 1975-06-02 | 1975-06-02 | Method of forming picture |
| JP66831/1975 | 1975-06-02 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1081523A true CA1081523A (en) | 1980-07-15 |
Family
ID=27299272
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA236,488A Expired CA1081523A (en) | 1974-09-28 | 1975-09-26 | Electrophotographic materials containing sublimable dyes |
Country Status (4)
| Country | Link |
|---|---|
| CA (1) | CA1081523A (en) |
| DE (1) | DE2542820C3 (en) |
| FR (1) | FR2286423A1 (en) |
| GB (1) | GB1523610A (en) |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR1349629A (en) * | 1962-03-01 | 1964-01-17 | Agfa Ag | Electrophotographic reproduction process |
| DE1522638A1 (en) * | 1965-11-09 | 1969-10-02 | Gen Aniline & Film Corp | Developer for liquid-liquid electrophotography and process for developing color photographs |
-
1975
- 1975-09-19 GB GB3846575A patent/GB1523610A/en not_active Expired
- 1975-09-25 DE DE19752542820 patent/DE2542820C3/en not_active Expired
- 1975-09-26 CA CA236,488A patent/CA1081523A/en not_active Expired
- 1975-09-26 FR FR7529558A patent/FR2286423A1/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| GB1523610A (en) | 1978-09-06 |
| FR2286423A1 (en) | 1976-04-23 |
| DE2542820B2 (en) | 1980-11-06 |
| DE2542820C3 (en) | 1981-07-09 |
| FR2286423B1 (en) | 1982-10-01 |
| DE2542820A1 (en) | 1976-04-01 |
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