DE2333677B2 - Electrophotographic emulsion developer - Google Patents

Description

3 4

not only the complete transfer of the developing the continuous phase with the aqueous phase

th, sticky image, it also helps the photo-emulsified.

Conductive surface pure for a longer period of time. For this purpose, the aqueous and the continuous to keep. If the photoconductive surface becomes contaminated in a colloid mill for 3 minutes it can be ground with the use of 5. The emulsion developer obtained is suitable for releasing agents easier to clean. net for the development of negatively charged latent elec-

The invention thus provides an aqueous trostatic image. The excess developer emulsion made available in which the organosol is liquid with a squeegee or through a slot nozzle removes the continuous phase and water which disperse. During the development process Phase is so that when a latent elec- io is developed, the emulsion is localized by the settling of the liquid trostatic image water in place of a light phase to form the desired copy burnt hydrocarbon liquid is released. Here. The water phase forms through to the background Air pollution will essentially represent droplets. These water droplets become reduced, compared to the developer, with which a slot or blow nozzle removed and backed up the light weight 15 used as a carrier for the toner leave the background of the recording material Hydrocarbon solvents evaporated to become completely dry. An emulsifier was used in Example 1 got to. not applied. The emulsion turned off shortly after

The following examples are used to further clarify that it was manufactured. The defoamer

purification of the invention. was mainly used to treat the vesicular

ao education in marriage, which is undesirable,

^. to counteract.

example 1

The continuous phase is formed as follows: Example 2

37.5 g vinyl-toluene-acrylate copolymer, 35 The following organosol was produced: 40.5 g copolymer of butadiene and styrene in a ratio of 75/25, produced by 37.5 g vinyl-toluene-acrylate copolymer, Solution polymerization, 10.0 g copolymer of butadiene and Sty-100 g hydrocarbon solvent with rol,

an initial boiling point of 159 ° C and 30-100.0 g of hydrocarbon solvent a final boiling point of 182 ° C, for

mostly consisting of aromatic were mixed together. To this mixture Hydrocarbons, Kauri-butanol number, were 240 g of the toner component from Example 1 = 91st and 1000 of the isomerized, paraffinic carbon

35 hydrogen and for 3 minutes in a These ingredients are ground together with 1000 g colloid mill, isomerized, paraffinic hydrocarbon with The water phase was prepared as follows:

a specific gravity of 0.75 at -17.8 ° C,

ie with substantially 100 ⁰ / oig pure isoparaffi- 400.0 g of distilled water,

Chemical hydrocarbon in an emulsion mill 40 0.1 g surfactant,

emulsified at a great rate. 0.1 g of an anti-foam agent

A corresponding toner is then produced as follows: were mixed together. The surface-active Means has emuigating, wetting properties

100 g microlith black (pure carbon black with a 45 and dispersing properties. It contains alkyl density of about 1.3), aryl polyether alcohols, sulfonates and sulfates and

12.5 g reflex blue (pigment) is of the non-ionic type. Its hydrophilic lipo-

25.0 g vinyl-toluene-acrylate copolymer, phile equilibrium (HLG value) is 12.4. As an anti-25.0 Any suitable anti-styrene can be used as a copolymer of butadiene and foaming agent Use 50 foaming agents, such as a silicone defoamer, which are effective in very low concentrations with a sufficient amount of toluene.

sets in order to achieve a suitable grinding viscosity. Another emulsifier consists of polyoxyalkylene

This mixture is processed in a cavitation mill. Derivatives of sorbitan fatty acids. grind, and 120 g of the toner become that in the 55. The emulsion is made by emulsifying 100 g Circulating organosol added to the grinder. of the isomerized, paraffinic hydrocarbon

The aqueous phase is made up of the following components with 250 g of the organosol together with that share formed: described water phase produced. The Emulga

tion can be done in a homogenizer, a colloid

125.0 g of distilled water, 60 mills or in a sonic or ultrasonic emulator

0.5 g of an anti-foaming agent, for example greed device. It was found that a

wise, the condensate from the ethylene oxide colloid mill does not emulsify as well

and stearic acid and such as an ultrasonic emulsifier. The better the di-

1.25 g starch (protective colloid). the greater the ratio of what-

65 ser to adhesive toner. With good emulsification

To form the emulsion, 250 g of the effect can then be used of the isomerized, paraffinic carbon continuous phase, which is mixed with 7 g of hydrogen, which is now used in the batch. turpentine is added to it, and then it will be substantially reduced or completely eliminated

den, so that a pigmented solution of a high molecular resin emulsifies directly with water the latter forming the disperse phase.

Example 3

A release agent such as polyethylene wax was added to the substances mixed in Example 2 Polyvinyl stearate, polyvinyl chloride resin, silicone resin or a reactive silicone liquid, in Quantities between 4 and 14 g. The release agents are developed together with the organosol and support the transfer of the developed image from the surface of the recording material onto the image receiving material.

Claims (9)

Such an emulsion developer is known from DT-AS 1097269. In the known emulsion developer, the carrier consists of a liquid, for example water or a gas, such as 1. Electrophotographic Emulsion Development _ü V. _{to £} F y ^ _{nat e} ine such surface tension ler from a solution of a pigmented roiy- a ^ ^ _{ntwickler se} ib _s t, so the liquid phase of mers in an organic solvent ais _F ^ ₀ U _{615 o} f the surface the continuous phase of the carrier phase and water as a disperse j = · ^ ^ _{&] n} , _atent electrostatic BUd never phase, characterized in that _{deraeS can} hit if the carrier is the polymer from a vinyl-toluene-acrylate aerge * - S ^ _Berühning ^ t _{brings the} picture. NachMischpolymerisat or a butadiene-styrene io ^. ^ _{Em that} does not exist _{such a} developer geMischpolymerisat and that the disperse ι s ^ _lateQtes electrostatic image contains an aqueous phase, an anti-foaming agent. To transmit image receiving material. 2. Emulsion developer according to claim i, da- ο »« ν of the present invention, the creation is characterized in that the solvent a ^ _{n EmulsionS} developer, the aromatic hydrocarbons to be drained with 15 rough carrier liquid is water, so that a Kauri-butanol- Number in the order of YyYYY «^ _nic | _{t is} excessively contaminated and contains 90% of it. . _m j _{st able} to _sheep) a sticky toner image 3. Emulsion developer according to claim 1, da- u paper can be transferred. by in that the pigment consists of micro 4 ^th _"rLösun" this object, the invention proceeds from crolithschwarz (pure carbon black having a density of * o f ^u, * said emulsion developer 1.3) or Reflexbau (pigment substance). from ^ _eh 3 _in ^g _dun ^g _{gs according to)} that the poly- 4. Emulsion developer according to claim 1, ge """ _{m V} to _yl j _ro i _uo i_Acrylat-Mischporyme characterized by a small amount of a mer ^ butadiene-styrene copolymer separating agent with electrophoretic properties _{and that the disperse aqueous} phase is an antite in the continuous phase. ^a 5 ^, aummittel contains 5. Emulsion developer according to claim 1, the _latent electrostatic image is characterized in that the aqueous phase of the _{surface contains} such an emulsifier as a surface-active emulsifier which _develops , then the adhesive becomes more soluble in the continuous phase as what- »^ JJ ^ _loaded places attracted what a this is. uc ^ n causes local breaking of the emulsion. The free 6. Emulsion developer according to claim 5, da- lories ^ _{different ways characterized in that the surface-active gg ^ JJ * _e ^k _{nt either by} evaporation, Ab-emulsifier a hydrophilic üpophdes equal ^ ¹ J _{n ode} ; _{Blow off} , then it can weigh about 12. "Sticky toner image on the image receiving material, 7. Emulsion developer according to claim 1, that 35 Kieonge: _e ei _gne tes paper, transferred, characterized in that the aqueous phase em »^ J ™ ^ ⁸ pSoto-conductive surfaces contain protective colloid. Γ U ^ ₂₀ Bt hydrophobic trinitro-fluorenone and 8. An emulsion developer as claimed in any of arrival ρ ¹ ^^^^^ on a conductive claims 1 to 7, characterized by a continu- Po ^ nyi ^ ar ^ ^^^ _bedampftem nmerliche phase of 4 »W ^ _Verweij ligand. 3.5 to 5.5%> of the high molecular weight poly. It is advantageous that the inventive emul- mers, sion developer a predetermined hydrophilic-lipo- 32.0 to 52.0%> light hydrocarbon _{helps to maintain} equilibrium and is non-conductive. Solvent, _{45 The} solvent for continuous or where the light hydrocarbon liquids are lipid phases ^^^^^^ about 900/0 isoparaffinic and about 10 · /. aromatic substances with ^OT « ^K a ^ -B ^ olz ^ in which contains hydrocarbons and where order of 90; fj. the high molecular weight polymer in the aromatic black pure carbon black with see hydrocarbon liquid is dissolved, 0.5 50 or reflex ^ au (Ptgmen Α ^ ΪΤ AND ^{THROUGH A DISPERSE WATER} " XS from ^ ^ ^ _{continuous phase more} soluble than what 43.0 to 63.0% water, ser. 0.01 to 0.15% of the surface-active _{55 Un} j to impart stability to _{the emulsion} Emulsifier and · _{en] r} ig _{n gee} ete emulsifier are used. Of the 0.01 to 0.15 »/ ο of the antifoam. However, emulsifier must always be more soluble in or 9. Emulsion developer according to claim, that are better wetted wjte "" "^ characterized by that the continuous phase as m or from the disperse, aqueous phase. Phase 0 ^g f to Ä ^ne contains the release agent. 60 The surface-active emulsifiers are neither fully lig hydrophilic still completely lipophilic. The disperse aqueous phase can still continue contain a protective colloid, overall the ii blibi ^^ W "" ⁸ ? ^ «^ a Sc The invention relates to a elektrophotographi- emulsion in any ^^?. ^^ see developer emulsion of a solution of 65, for example, grinding in ^ ™ ° g ™ **** "pigmented polymer in an organic solu- a homogenizer and with an acoustic or . ÄtLr ^{iiliCher PhaSe And WATER U} r ^h ri7 Release agent supported