DE2006003C3 - Electrophotographic suspension developer - Google Patents

Description

^ n ^ 4), -COONH ₂

IO

—COOH

It is known to use electrophotographic suspension developers for making multicolor copies in Her way to prepare that different colored pigment particles coated with natural or synthetic resins that act as control substances and dispersants and coated particles separated by color as a toner in a carrier liquid be dispersed. If you now use such a developer kit on dektrophotographic If you want to make a multicolored copy of a multicolored original, you have to do this Electrophotographic recording material is electrically charged, exposed and developed several times e.g. to make a black, yellow, red and blue partial copy one after the other. if the developers used here contain toners whose pigment particles or resin coating have a have high electrical resistance, then get the respective image areas shown above a much higher electrical resistance than the non-image areas, creating a uniform electrostatic charging of the photoconductor layer of the recording material for the following color copying process difficult and thus the color balance is impaired. In other words, prevented the high electrical resistance of the image areas means that these areas are completely discharged during exposure, which leads to the fact that the toner during the development also in these (already developed) image areas adheres and thus makes it difficult to produce a clean multicolor copy of the original. Same Difficulties arise when the developer substitute -NiCH) -COOH

Toner enihält whose pigment or a resin coating ₄ o (mjlLgtach -CH ₃ NO ₂ -NH ₂ N (CHJ having ₂ ^ COOH, low electrical resistance. Also in -COOCH _3, -OH, -OCH _3, Cl and nrj. This In this case, uniform charging of the photoconductor layer of the recording material is impossible after the first partial color copy has been made; furthermore, those areas that are still supposed to retain a residual charge are discharged to a greater or lesser extent, so that the toner does not stick to these areas during subsequent development that in turn the production of a multicolor copy of the original is made more difficult.

To improve or avoid the disadvantages outlined, pigment particles have already been proposed with polymers or copolymers with units of the formula

35

(with L as above).

(with L as above and η = I to 4) and

H A

- (CH ₂ )

I I cc

Y X

(I)

(with L as above and η = 1 to 4) and A is a 6o hydrogen atom or —CH, and / or with —H, —Cl or —COOII. X -C ₁₁ H ₁ ,,,, units of the formula -OCOC ₁₁ H _{211 +} , (I ^ »g4), -OC ₁₁ II _{211 +} , R ₁

,. == .. = -.,. -CN, - COOH, -Cl, -COCI, -COOR |

(with R equal to -C ₁₁ H _{2n + 1} [I £ n £ 4]), CH ₂ = C

in the Y

-CH ₂ CH

CH,

in which R ₁ —H or —CH ₃ and D is an alkyl radical

with 5 to 20 carbon atoms, —OE with E being an alkyl radical with 5 to 20 carbon atoms or - COOR ₂ with R ₂ being cyclohexyl or an alkyl radical having 5 to 20 carbon atoms. .

It is an object of the invention to provide an electrophotographic suspension developer create of multicolored copies due to its favorable electrostatic properties in the context of successive charging and exposure processes, the formation of image-correct Partial color images of high density without an increase in density in the, based on the already developed Partial color images, respective non-image areas permitted.

This object is achieved with electrophotographic suspension developers as described in the claims are specified.

The suspension developers are suitable for the development of electrophotographic recording materials, which are electrically charged, exposed to form a latent image and finally are wet developed, as well as of electrophotographic recording materials that are directly image-appropriate charged and then wet developed.

Both inorganic and organic compounds, e.g. B. Pigments or dyes, e.g. B. carbon black (CI. No. 77 266), Aniline black (CI. No. 50440), real black (C. I. No. 50440) and spirit black (CI. No. 50415), Spilon red (CI. No. = Solvent Red 8), Spilonorange (CI. No. = Solvent Orange 5), Benzidine Orange (CI. No. 21 110), Brilliant carmine (Cl. No. 12 490), scarlet red (CI. No. 15 865) and real red (CI. No. 15 865), Spilon yellow (CI. No. = Solvent Yellow 19), benzidine yellow (CI. No. 21 100), benzidine yellow (CI. No. 21 095) and real yellow (CI. No. 13 135), Victoria blue (C I. No. = Basic Blue7), methylene blue (CI. No. = Basic Blue 9), oil blue (CI. No. 61555), alkali blue (CI. No. 42 750) and Valiecht blue (CI. No. 74 350), sky blue (CI. No. 62 100), cyanine blue (CI. No. 74 250), phthalocyanine green (CI. No. 42040), Seikahellgrün (CI. No. 42040) and Spilon violet (CI. No. = Solvent Violet 2).

The toners used in the suspension developers consist of either

a) photoconductor, pigment or dye and at least one polymer or copolymer with units of the formula I and / or U or from

b) photoconductor, pigment or dye and a copolymer chemically bonded to the photoconductor from monomers of the formulas I and 11.

In the production of the toner according to embodiment a), photoconductor and pigment or dye are kneaded either in the presence of a small amount of solvent with the polymer or copolymer with units of the formula 1 and / or 11 and in this way provided with a polymeric coating or in Mixture with the polymer or copolymer in a solvent, spray-dried, toner particles with a particle size of about 1 to 5 μm being obtained. The toner produced in the manner described can be compared to known toners substantially ⁶ S fixed on the electrophotographic recording material fixation, has better electrical properties and is more readily dispersible.

Luminaires are suitable as a coating for the photoconductor for example

Styrene / buladiene and vinyl toluene / butadiene

Copolymers,
Poly (butyl methacrylate),
Poly (methacrylic acid octyl ester),
Lauryl polyimethacrylate),
Polyimethacrylic acid cyclohexyl ester),
: Poly-n-hexyl vinyl ether,
Poly (butyric acid vinyl ester),
Polystearyl vinyl ether,
Poly-n-amyl vinyl ether and styrene / methacrylic

acid butyl ester,

Styrene / methacrylic acid lauryl ester,
Methacrylic acid hydroxyl ethyl ester / methacrylic

acid hexyl ester,
Glycidyl methacrylate /

Vinyl stearate,
Acrylic acid methyl ester / aminostyrene / meth-

acrylic acid styrene / acrylic acid octyl ester and
Methacrylic acid octadecyl ester,

Acrylamide copolymers.

Production of the toner according to the embodiment b) takes place by copolymerization of a monomer iahigen to the formation of a polymeric photoconductor, such as N-vinyl carbazole, vinyl anthracene, dimethylaminostyrene, Vinyl acrydine, 2-vinyl-4,5-diphenyloxazole. Bromovinylcarbazole, 2,3-chlorovinylanthracene, ο - chlorovinylcarbazole, 2,4 - dichlorovinylcarbazole, 2-chlorovinylanthracene and vinylacrydin with monomers of formulas 1 and II, in particular by emulsion polymerization after adding a pigment or dye. The toners obtained in this way have a more pronounced sense of charge and a better one Dispersibility than usual toners.

Conventional known carrier liquids, such as liquid paraffin, isoparaffin, olefin or naphtha hydrocarbons, optionally with the addition of aromatic hydrocarbons, with an electrical resistance of at least 10 ⁹ ohm cm and a dielectric constant of not more than 10 are suitable as carrier liquids for the individual suspension developers 3. Such carrier liquids are commercially available.

Since the suspension developers in the toner contain photoconductors with high electrical resistance, they can on the one hand in the case of copying partial color separations of a multicolored original image and imparting uniform chargeability to non-image areas of the recording material; on the other hand, in the event that the recording material is charged first and then is exposed, cause a rapid drainage of the charge in a desired area. Man achieves a faithful reproduction of a multicolored original without impairing the color balance.

The following examples are intended to explain the invention in more detail.

example 1

In 10 kg buffer solution with 2.88 g sodium hydroxide. 11.18 g potassium chloride and 9.28 g boric acid per 6000 ml 1 kg of N-vinylcarbazole was dissolved in distilled water while warming to 70.degree. The solution obtained was initially stirring vigorously

with a second solution of 20 g of Victoria Blue (Cl. No. 44 045B) in 100 ml of monochlorobenzene, then a solution of 2.5 g of azobisisobutyronitrile (starting agent) in 50 ml of monochlorobenzene and then 5 g of bentonite and finally, with constant stirring 4 Maintained at a temperature of 90 ^° C. for hours. An emulsion polymerization then took place with the formation of blue photoconductor parts. The photoconductor particles obtained were washed with water and methanol, dried, post-treated with monochlorobenzene, suspended in η-hexane and dried again. By suspending 10 g of the blue photoconductor particles obtained in 1000 ml of a commercially available petroleum hydrocarbon fraction, a ready-to-use suspension developer with blue toner was finally obtained.

In the same way, but replacing Victoria blue (Cl. No. 44045B) with spirit black (CI. No. 50415), Spüongelb (CI. No. Solvent Yellow 19) and Spilon red (CI. No. Solvent Red 8) were the Suspension developer made with black, yellow or red colored toner.

With the help of this set of four different colored suspension developers in the usual known manner, an exposed, commercially available electrophotographic recording material, consisting of a paper support and an applied ZnO binder layer, could be developed into a multicolor copy. This was done in such a way that first a red, blue or green separation was produced from a multicolored original one after the other with the help of a red, blue and green filter and a black separation was produced with the help of all three color filters. The photoconductive layer of the electrophotographic recording material was then uniformly charged negatively, exposed against the black separation and immersed in the suspension developer with the black-colored toner, a black copy being obtained. The recording material bearing the black copy was then recharged, exposed against the red separation and immersed in the developer containing a blue toner, a blue color copy (in the blue area of the original) being obtained. In the same way, a yellow color copy was obtained using the blue separation and the developer containing a yellow toner, and a red color copy was obtained using the green separation and the developer containing a red toner. All in all, a multi-color copy that was sharp and true to the original was obtained.

Example 2

100 g of a thoroughly kneaded mixture of the following particles in 1000 ml of a commercially available isoparaffin composition: The mixture dispersed gave a suspension developer with yellow colored toner.

Poly-2,4-dichlorovinylcarbazole 1 kg In the same way, but with replacement of

Spüongelb Spüongelb with a black, blue or red color

(CI. No. Solvent Yellow 19) 0.1kg 35 dye were suspension developer with black,

Chlorobenzene produced 5 kg of blue or red colored toner.

The developer kit obtained was equally suitable

was suspended in 15 kg η-hexane, whereby finely divided manner like the developer kit of Example 1 to the yellow color Particles were formed. 50 g of this position of multicolor copies.

Example 3

A kneaded mixture of the following composition:

Poly vinyl anthracene powder 1 kg

Styrene / butadiene mixed polymer ... 0.5kg
Brilliant carmine (CI. No. 12 490) ... 0.05 kg

was spray-dried to a red-colored powder with a particle size of about 1 μm. 20 g of the obtained Powder in 1000 ml of a 6: 4 mixture of two different petroleum hydrocarbon fractions dispersed gave a red toner suspension developer.

In the same way, but by replacing brilliant carmine with a black, blue or yellow dye, suspension developers were made with black, blue or yellow colored toners.

The developer kit obtained was suitable for production in the same way as the developer kit of Example 1 of multicolor copies.

Example 4

A mixture of

Anthracene - ^ Kg

Styrene; £ g

Acrylic acid butyl ester ² kg

Benzoyl peroxide ¹⁰ S

was polymerized in a nitrogen atmosphere by heating at a temperature of 90 to 100 ° C. 100 g of the polymer obtained were mixed with 10 g of phthalocyanine blue (Cl. No. 74 160) and 100 g of toluene kneaded, whereupon the resulting mixture becomes a blue colored toner powder of one particle size of about 1 μτη was spray-dried.

In a corresponding manner, but with replacement of Phthalocyanine blue by a commercially available black dye, benzidine yellow (CI. Nn 21 I00; and scarlet red (Cl. No. 15 865) a black, yellow and red toner was obtained, respectively. In the end 15 g each of the different colored toners were ir 1000 ml each of a commercial petroleum coal · hydrogen mixture dispersed, with one set before liquid suspension developers for preparation of multicolor copies.

In a corresponding way the in dei The following table contains two additional developer sets.

509641/113

ίο

Suspensions
developer Toner Beslandleile Photoconductor Vinyl compound Kick-off! dye Carrier liquid No. Vinyl anlhracene Styrene (0.75 kg) Azobisiso Methylene blue 1 (3 kg) Methacrylic acid butyronitrile (CI. No. Petroleum coal lauryl ester (10 g) Basic Blue 9) hydrogen- (1.25 kg) Brilliant carmine mixture (CI. No. 12490) the same Aniline black (C.I.Nr. 50440)) the same Benzidine Yellow (CI. No. 21090) the same Imidazole Methacrylic acid Azobisiso Brilliant carmine 2 (2.5 kg) butyl ester (1 kg) butyronitrile (C.I. No. 12490) 6: 4 mix Methacrylic acid (4.5 g) two (0.3 kg) different Petroleum coal hydrogen- Spilon black factions (CI.No. 50415B) the same Spylon yellow (CI. No: the same Solvent Yellow 19) Cyanine blue (CI. No. 74160) the same

The individual colored toners could either by spray drying or in the same way Adding the dye to the polymerization mixture, removing the solvent and pulverizing of the residue.

All of the developer kits were suitable for production in the same way as the developer kit of Example 1 of multicolor copies.

Example 5

In the ^{manner described in Beispie 1} 4, a mixture of

o-chlorovinylcarbazole 1.5 kg

Vinyl toluene 0.5 kg

Octyl methacrylate 1.0 kg

Azobisisobutyronitrile 6.5 g

Dichlorobenzene 100 ml

Methylene Blue (CI. No. Basic Blue 9) 14 g

Buffer solution according to Example 1 18 g

emulsion polymerized. 20 g of the blue reaction product thus obtained were dissolved in 1000 ml of carrier liquid dispensed. whereby a suspension developer with blue toner was obtained.

In the same way, but with the replacement of methylene blue (CI. No. Basic Blue 9) by spirit black (C.I. No. 50415), benzidine yellow (C.I. No. 21 100). Fast red (CI. No. 15 865) or benzidine orange (Cl. No. 21 110) resulted in a black, yellow or red toner. In each case 15 g of toner are dispersed in each 1000 ml of carrier liquid. resulted in a developer kit.

Since the toners produced in the present case as a result of interpolymerization of the photoconductors with the Vinyl monomers consist of copolymers.

the suspension developer containing such toner remains even after long-term storage or repeated storage Use unchanged effective. The electrostatic properties of this suspension developer corresponded to the electrostatic properties of the suspension developers of the previous examples.

Claims (2)

Patent claims: 1. Electrophotographic suspension developer composed of an insulating carrier liquid and a toner composed of a pigment or a dye and photoconductor particles which are mixed with a polymer or copolymer incorporating the formula H A I I - C = C (I) YX in which Y —H, -Cl or -COOH, X -C _n H _{2n + 1} (1 ^ / i ^ 4), -OCOC _n H _{2n + 1} (1 ^ η ^ 4), -OC _n H _{2n +} , (1 g η g 4), —CN, -COOH, -Cl, -COCl, —COOR (with R being -C _n H _{2n + 1} [l | n ^ 4]), -CH ₂ CH _{-CH 2} -C ₂ H ₄ OH, -NHCOCH ₃ or - (CH ₂ J ₁₁ N (1 I i! I 4). -COONH ₂ , -COOH, -COOCH ,, -OH, -OCH. ,,
and -Br), (with L as above). - (CH ₂ J _n L L (with L as above and / 1 = I to 4) and - (CH ₂ ) ,, (with L as above and / 1 = 1 to 4) and A - H or --CH, denotes, and or with units the formula CH ₂ = C (St. in which R ₁ - H or - CH ₃ and D is an alkyl radical with 5 to 20 carbon atoms, - OE with E is an alkyl radical with 5 to 20 carbon atoms or - COOR ₂ with R ₂ is cyclohexyl or an alkyl radical with 5 to 20 carbon atoms , are coated, characterized in that the toner photoconductor particles made of anthracene, oxadiazole, thiadiazole, 5-aminothiazole, 4,1,2-triazole, oxazole, thiazole, imidazole, pyrazoline, styrylpyrazoline, pyrazine, triazole, quinazoline, benzofuran, acridine, Carbazole, polyphenylenethiazole, 9-benzylidene fluorene. Diphenylene hydrazine, amyl hydrazine, benzyüdenaniline, a polyene, ethylene derivatives, copper acetate of 2-oxy-4-methylazobenzene, heavy metal salts of mercaptobenzothiazole, mercaptobenzoxazole or mercaptobenzimidazole, mixed and polymerized condensation products of aldehyde and vinylic caryl amine, reaction products with aldehyde and vinyl aromatic amine, reaction products of aldehyde and vinylic amine with vinyl anthracene, vinylacridine or 2-acrylamide units. 2. Electrophotographic suspension developer composed of an insulating carrier liquid and a toner composed of a pigment or dye and photoconductor particles to the at least a polymer compound is chemically bound, characterized in that it is used as a toner a copolymer of N-vinylcarbazole, ο - bromovinylcarbazole, ο - chlorovinylcarbazole, 2,4-dichlorovinylcarbazole, vinylanthracene, 2-chlorovinylanthracene, 2,3-dichlorovinylanthracene, dimethylaminostyrene, Vinylacridine or 2-vinyl-4,5-diphenyloxazole, a compound with units of the formula I and a compound with units of the formula II. (with L equal to -CH. ,, NO ₂ , -NH _2. -N (CH ₃ I ₂ .