DE7438730U1 - Imaging single layer - Google Patents

Description

PATENT LAWYERS. : Ä.'BRÜNECKER

H. KlNKELDEY

ΟΊ-ΙΝΟ

W. STOCKMAIR OR HK «at (CALTECM

K. SCHUMANN

OR Wft NAT OFl-PMVS

P. H. JAKOB G. BEZOLD

B MUNICH 22

MAXIMIUANBTRASM «3

PH 8710-46A March 12, 1979

^ Image single layer ^)

The invention relates to a mapping simplicity.

In a known monochromatic imaging method, a donor material is produced in such a way that one Applying a layer of a photosensitive imaging material to a substrate. To produce an illustration the imaging material on the donor material is activated by treating it with a swelling agent or a partial Solvent treated. This activation has a dual function in that the upper surface of the donor material is lightly becomes sticky while at the same time being structurally weakened so that it can be more easily broken along a sharp line defining the image to be reproduced .. When the donor material is activated, a recording material is placed on the donor material. An electrical potential is then applied between this arrangement while the arrangement is exposed imagewise on the same side. If the separation of the donor and the receiving material breaks or tears the imaging layer along the lines, those through which

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imagewise exposure "can be determined" whereby part of the imaging layer is transferred to the receiving material, while the remainder remains on the donor material. A positive image _{1 is} thus produced on one material while a negative image is produced on the other.

Such a system can produce monochromatic images with excellent resolution and density. Venn however, one tries with this known system a color image using different colored pigment particles Manufacture by making the various pigment particles in a dispersion is mostly obtained unsatisfactory results. This is due to the fact that particles of different colors are randomly arranged across the thickness of the recording layer. this can lead to particles of different colors, especially in areas that should be monochrome, cover after separating the donor and receiving material.

The present invention is based on the object of specifying a single imaging layer with which color images are included both good color separation and high color saturation can be obtained.

This object is achieved according to the invention in that the layer of composite particles with particulate! The dye and the photosensitive pigment are contained in an electrically insulating liquid.

In the case of the imaging single layer according to the invention the choice of the pigment material is no longer so critical, as the pigment material only has the function that it responds to a predetermined range of wavelengths,

on the other hand no more than the coloring agent in that respective particle is used. Since the dye particle is in each compound particle is relatively small, can be, there is a high response probability of the particle, since practically all light quanta absorbed lead to a migration of the particle. The proportion of light that is absorbed by the coloring agent on the other hand is relatively low. Nevertheless, an extremely high color saturation can be achieved in that then the dye particle is colored in each case in the corresponding substrate. Here unfolds the dye has a color strength that leads to a number of factors higher color saturation than with help of pigment particles was possible until then. Furthermore, the single imaging layer according to the invention enables also a color inversion, through the use of pigment particles which respond in a predetermined wavelength range and an associated dye which is a color complementary to the wavelength range in question having. Finally, in the case of the single imaging layer according to the invention, the image obtained can also be thereby obtained be increased that after the dye in dta respective image carrier is colored, the pigment particles are still removed from the image.

In the following the invention will be described in more detail with reference to the Drawings are explained. In the drawing show:

Fig. Λ in a schematic position a side cross-sectional view of a photosensitive imaging body with an imaging single layer,

Pig. 2 one possibility, the imaging single layer to supply an electrically insulating liquid,

Fig. 3 shows the exposure of the imaging body with different colored light,

4 shows the separation of the imaging body for generation of a colored end image, and

Fig. 5 the charging and exposure at an expedient Embodiment of the invention.

As a preferred embodiment, FIG. 1 shows a single-layer layer of particles with which a colored image can be produced. A color imaging body 1 is made up of various components. The donor material 2 has on one surface a layer of imaging material containing a single layer of a plurality of three different electrically photosensitive composite particles randomly intermingled - these composite particles are colored magenta, yellow and cyan. The different dye, the composite particles in Fig. 1 are designated by "M" for mageirca, ¹¹ Y "for yellow and" C "for cyan.

Each electrically photosensitive composite part ¹ * ^ n 3 A in layer 3 of Fig. 1 has a single color and is composed of a particulate dye 3.B and an electrically photosensitive pigment 3 C supported on a binder 3 D. The light-sensitive pigment is referred to as the control material, since the photoreaction takes place in this material during the imaging process of the particle.

are connected by 3 D, it should be noted that they are mil; The binder can be connected in any way For example, they can be enveloped by the binding agent or partially Be embedded in the binder- In terms of the dye material, however, it is to support the Dye coloring of the finally with the picture; provided Image carrier material required that the dye is arranged on or in the vicinity of the surface of the binder is. In this way a maximum amount of dye can be inked into the image carrier surface, see above that an optimal color density is obtained. As further shown in Fig., An optimal situation is given when the particulate dye 3 B is bonded to the surface of the binder 3 D. The use of particles that contain a binder, because of the simplified handling preferred. However, the best images are obtained with particles made up only of a pigment material and a particulate dye.

In general, the composite particles are 3 Å a mean diameter of 0.5 to 25 pm- during manufacture of this type of particle, the composite particles larger than 25 µm in size become the above Ground down area. Preferably the particles are from about 0.5 to 15 µm in size that the composite particles consist of an agglomerate of smaller, discrete composite particles can be constructed and still the function of a single composite particle 3 A in the single-layer Fulfill the imaging layer of FIG.

The imaging layer shown in the drawings represents a statistical mixture of differently colored, electrically light-sensitive compounds (particles represent * so that overall a uniform color is achieved. As can be seen from the drawings, the top and bottom are of the composite particles are not necessarily coplanar with one another, nor do the composite particles touch each other Particles are necessarily or are arranged at a predetermined distance from one another. The imaging layer represents is a single layer of composite particles and is consistently referred to as a single layer. However, it is it goes without saying that such terminology encompasses any configuration of composite particles, which represent less than two complete and superimposed layers of composite particles. This statistical single layer ensures excellent color separation in the imaging process.

In Fig. Λ , the single-layer layer contains three kinds of differently colored particles. For example, a first type of magenta composite particle, a second type of yellow composite particle, and a third type of cyan composite particle are used in separate batches (single mixtures), according to here. described method produced; then all three! Simple mixtures and mixed by sound application \ evenly dispersed. A satisfactory dispersion j by sound Application can be effected winding devices with any standard dispersants}. The uniformly dispersed and randomly I composite particles are then layer-shaped Ü on the donor material 2 having a thickness which is approximately |

is equal to the diameter of the composite particles, upset. Coating processes suitable for this are des Known to those skilled in the art. Suitable coating processes are those Extrusion, coating with a slot die or doctoring to the desired layer thickness. After the Schicifc has been applied, the imaging layer consists of a Single layer of randomly distributed particles, as in. Fig. 1 shown. Unless otherwise indicated, mean the terms "electrically photosensitive composite particles" or "composite particles" both embodiments of the imaging particles as described above.

In Fig. 1, the donor material 2 has a conductive backing layer 4- This conductive backing layer is preferred there, where the encoder substrate 2 is insulating, and can be omitted there where the encoder substrate 2 is relatively conductive, 2.B. in the case of cellophane. In contact with the upper surface the imaging layer 3 is a recording - material 5 · If the receiving layer 5 is insulating, possesses As shown in FIG. 1, they have a conductive backing layer 6. This conductive backing layer can be omitted if layer 5 is conductive. Whether a potential is now being applied or charges are applied, the requirement is to expose the imaging layer to an electric field and exposing the electrically photosensitive composite particles to electromagnetic radiation, which causes the exposed composite particles to separate the receiving material from the donor material selectively adhere to materials 2 or 5.

As can be seen from the prior art, in particular from the

U.S. Patents 3,595,770, 3,64-7,659, and 3 W 93 *, may have a Variety of materials and arrangements, e.g. B. a charged one insulating tissue, serve as electrodes. With the help of two opposing electrodes the electric field penetrating the imaging layer can then be generated. The exposure and the application of the electrical field can, if necessary, also take place one after the other. As described in US Pat. No. 3,616,395, the free surface of the imaging layer also under one be exposed over this extensive field without that the figure £ .layer at that time was sandwicii-like is enclosed between two bodies.

In Fig. 2 is a measure for preparing the imaging- layer, i.e. the application of an insulating liquid to prepare the layer for imaging. As can be seen from Fig. 2, the composite particles are covered with an insulating liquid, which enables electrophoretic imaging. After that The absorbent material 5 is applied to the wet single layer with the aid of a pressure roller 9, the insulating liquid The particles are pressed on to avoid any air bubbles in the imaging monolayer. For this Any insulating liquid that is not a solvent for any of the components of the substrate is suitable or the composite particles. The expression "Insulating" means here that the liquids have one

Ίο

resistivity above 10 ohm · cm or have such a specific resistance that the collapse of the electric field in the figure ^ layer during the figure is prevented. Examples of such Liquids are aliphatic hydrocarbons, liquid silicones or fluorinated hydrocarbons. A special one An example of this is an odorless, aliphatic hydrocarbon solvent.

In the further course of the production of a multicolored picture using a donor material described above, the imaging layer is then combined with a multicolored original, exposed for example by means of projection through either the donor material 2 or the receiving material 5. Fig. 3 shows schematic] table this exposure of the imaging layer with light under-

ΐ different wavelength ranges produced by the donor material 2 is irradiated. Area 9 represents the projection of white light, area 1o an area without (light irradiation, area 11 the projection of

ι red light, area 12 the projection of blue light,

the area 13 the projection of green light and the area 14 · the projection of yellow light.

During the exposure of the imaging layer 3 nothing different colored light, is generated by means of a voltage source 15 between electrodes, which are covered by conductive layers 4 and 6, an image penetrating the imaging material 3 electrical ELd generated. The polarity of the potential applied to the transmitter material 2 can either be po- positive or negative, with a preferred polarity orientation for some substances, be- preferably applied electrical Fields range from about 5 ° to about 5,000 yoIt per 25 .mu.m, based on the imaging body that the donor— and receiving material. If e.g. a 5 ° pn thickness Polyethylene terephthalate film for both the donor material 2,

ι as used for the receiving material 5, amount to.

the preferred voltages used are about 2,000 to about zo, 000 volts. In order to maintain the mechanical strength of the single-ply imaging layer, a voltage is preferably applied to the donor and receiving material before the receiving material is brought into contact with the wet imaging layer. It is desirable that a resistor 16 having a resistance on the order of 1 to 20 I © hm be included in the circuit. This resistance prevents flashovers between the imaging layer 3 and the receiving material 5 when this

brought together or separated.

During the exposure, the imaging body 1, as shown in Fig. 4 shown separately, with a visible multicolored. Image is created. With subtractive color formation, as in Fig. 4, the positive color image that the Original corresponds, generally formed on the donor material 2, while the negative color image on the receiving material 5 is created. The applied voltage is maintained on the imaging body during the separation process.

As shown in Fig. 4, the projection of white results. Light in area 9 in the transmission of magenta, yellow and cyan colored individual composite particles on the receiving material 5 »with a white or transparent surface richly remains on the donor material 2 - Where the imaging layer is not struck by light, as in the area 1o, all the individual composite particles remain on the donor material and form a black one there Area. Where red light is projected, as in area 11, any exposed becomes cyan Material transferred to receiving material 5 during separation, leaving the magenta and yellow areas that are together appear red to the eye. Where the imaging material is struck by blue light, such as in the area. 12, that will transferring yellow material, leaving behind magenta and cyan which together appear blue to the eye - where that Imaging material is hit by green light, as in area 13, the magenta material is transferred, with yellow and cyan, which together appear green to the eye. Where the imaging material is hit by yellow light becomes, as in area 14, the magenta and cyan material transferred, leaving only yellow - if you look at the entire surface of the donor material, a faithful multicolored reproduction of the colored original.

Finally, "in the case of the one in FIGS. 1" to 4 are indicated Preparation of an image with the imaging single layer of the particulate dye each particle as described below The donor or receiving material is colored and, if necessary, are then the photosensitive pigment materials and / or the binder, if such was used, removed. By coloring it becomes a particularly saturated and aesthetically pleasing one Color image achieved. When the dye off material Molecularly penetrating a substrate, this causes the conversion of the dye from its particulate. State into a molecularly disperse form so that a more aesthetically pleasing, richly colored image is obtained will. In general, the coloring of the dye in the substrate will change the Image changes from a pale color to a brilliant, rich, appealing color. To color the image carrier or generally to achieve a substrate with the particulate dye, the dyes specially selected so that a dispersion in the particular image support material is obtained. So you need to for an image that is to be created exclusively on an image carrier, the selected special dyes in allow the image carrier material to disperse. You can use any single dye dispersion (coloring) Measures are brought about, which the necessary Cause coloring. In the case of a polyester substrate, can disperse the dye by heating the image on the substrate at 175 ° C for a period of 2 to 5 Minutes can be achieved. In the case of other substrates it may be that coloring with the help of a dye

solvent leads to better results and is therefore preferred. The picture can of course initially from either the receiving material or the donor material be transferred to another substrate surface, in which the dye coloring then takes place. For example, the coloring can be done in a suitable resin layer, such as in a suitably coated paper, by heating or solvent coloring.

An image made up of the composite particles of FIG. 1 can be displayed on a. Made of polyethylene terephthalate surface will. The individual dyes are colored by heating the polyester material to 175 ° C for a duration of 3 minutes. The remaining photosensitive control pigment particles and the binder will from the image surface by washing with various types of organic solvents such as trichlorethylene, Benzene or acetone. That in the surface of the polyethylene terephthalate layer, which the aforementioned Solvents in which the dye is usually soluble, resists image obtained, is very durable, and the brilliant colors are aesthetically pleasing.

In the process _? As described with reference to Figures 1, 3 and 4, numerous other materials can be used for each of the components of the imaging body. If conductive backing layers 4 or 6 are used, they can be rigid or flexible and contain any suitable conductive material: Typical conductive materials are metals such as aluminum, brass, steel, copper, nickel or zinc, metallic coatings on plastic substrates Rubber made conductive by incorporating a suitable substance, or paper made conductive by incorporating a suitable material or conditioning in a humid environment to ensure the presence of sufficient amounts of water to make the material conductive.

Of the. Donor material 2 or the receiving material 5 should at least one be transparent, so that thereby, a;

Image projected on the Abbil manure layer can- examples ψ game as are about Polyäthylenterephthalafcf olien very well here geeignä. Suitable insulating materials for use in the transmitter or air supply materials 2 and 5 are polyethylene terephthalate or cellulose acetate, with a backing layer made of conductive electrode material, for example vapor-deposited tin oxide, possibly being provided.

As mentioned above, the individual dyes can preferably be incorporated into the layer material used for the finished image color. If the transmission of an image is in ^ - costume comes, the dyes used should have the ability the coloration in the transfer material, as in the case of gelatin coated paper. Typical conductive translucent materials are cellophane Conductive coated glass, such as glass coated with Ziun or indium oxide, glass coated with aluminum, or Similar coatings on a plastic substrate. In many cases, a tin oxide coated glass is used as it is a good conductor, is highly translucent and easily accessible.

The composite 3e sets the imaging particles 3 A can; each contain suitable electrically photosensitive material. A satisfactory figure takes place with compound Particles up to about 25 µm in diameter instead, and preferred results are obtained with diameters of about 5 to 15 µm. Typical, intensely colored Electrically light-sensitive substances are e.g. Algolgelb GG, 1,2,5,6-Di- (C, C'-diphenyl) -thiazolanthraquinone, CI-, No. 67300; Calcium litho red, the calcium salt of 1- (2-

Azonaphthalene-1'sulfonic acid) -2-naphthol, CI. Kr. 1563o; Cyan GTNP, the ß-Foria of copper phthalocyanine, CI. Kr. 7 ² HoO; Diana blue, 3,3'-Iiethoxy-4,4'-diphenyl-bis (i "azo-hydroxa-3" -naphthan.ilid, CI- Kr. 2118ο; Duolcamd.n, the calcium salt of 1- (4 ^l - Hethoxya2ob8azole) -2'-sulfonic acid) ^ -hydroxy ^ -naphthoic acid; Indofast Brilliant Scarlet Toner, 3j4-, 9, lo-Bis-N ^ '- Cp-methoxyphenyl ^ imidolperyleii, CI No. 7114-O; Indofast Yellow Toner, Flavathron, CI-No-7οδοο; Methyl violet, a PhospnorwolfraEmolyb &. 'Insals of 4- (n, N'-Trimet'aylanilion) -Eietliylen-N ^lt , H ⁿ -dimetliylaiiiliniuiii chloride, CI. No. 42535; ffaptholrot B, 1- (2'-Metho3cy-5 ^r nitronphenylazo) -2 ~ hydroxy-3 '-nitio-3-naphthanilide, 12355 "Quindopurpur EV-58o3, a substituted quinacridone No. CI;.. Vulkanechtrot 3BE toner 35 ~ 22o1, 3, 3'-Dimethoxy-4,4 ^l -bi-phenyl-bis (1 "-phenyl-3" -iaethyl-4 "-azo-2 ^ir -pyrozolin-5" -one) C .1. No. . 2i2ooj Watchung red B, 1- (4'-Metb.yl-5-chlorazobenzene-2'-sulfonic acid) -2-hydroxy-3-n.aphtholic acid, EI No. 15365; or pigments, such as purified N- 2 ^W -Pyridylu, i3-dioxodinaphtho- (2,1-b; 2 ¹ , 3 ^l -d) -furan-6-carboxamide, as well as other compounds, prepared according to US Pat. No. 3,448,029 and 3 4o2 177. Typical light-sensitive Substances are 2,5-bis (p-aminophenyl) -1,3,4-oxadiazole, 4,5-diphenyl-imidazolindine, N-isopropylcarbazole, triphenylamine, triphenylpyrxole, 1,4-dicyanonaphthalene, 1,2,5 , S-Tetraazacyclooctatetraen- (2,4,6,8), 2-phenyl-4-rnaphthylidenecoxazoles, 6-hydroxy-2,3-di- (p-methoxyphenyl) -benzofuran, 6- ^ ydroxy-2, 3-di (p-methoxyphenyl) -benzofuran, 5-benzylidene-aminoacenaphthene, 3-amin.ocarbazole, or he mixtures of the aforementioned compound. All of the aforementioned photosensitive substances can, if necessary, be sensitized with suitable sensitizers or Lewis acids. Typical Lewis acids are, for example, 2,4-, 7-trinitro-9-fluorenone, 2,4,5,7-tetranitro-9-fluorenone, picric acid, 1,3,5-trinitrobenzene and chloranil.

Jk ^

As a binder or resin material for the composites Particles can practically all insulating resins or polymers be used. Preferred copolymers are polyethylene, modified styrenes, styrene-indene-acrylonitrile terpolymers, Vinyl acetate-ethylene copolymers, vinyl chloride-vinyl acetate copolymers sate, styrene-vinyltoluene-C © polymers, Polypropylenes or mixtures of the foregoing. Polymers. The "use of an electrically insulating Binder is preferred because it enables the application of a wider range of electrical field strengths will. Modified polystyrenes lead to optimal results, however, the invention is of course not limited to the use of these polymers.

Typical classes of dyes are types of the main chemical classes, such as azo dyes, anthraquinone dyes or triphenylmethane dyes. The only requirement for any dye is that it be the appropriate one Color owns. Of particular use are those. Fabrics that include polyesters, polycarbonates, cellulose esters and. -ether, as well as methacrylate polymers. Preferred dyes which are soluble in polyester films are e.g. Foron Eabine S-2BFL (Mfr. Sanoz Corporation); Dispersol red B-3B (Mfr. ICI) j Eastman polyester ^ r blue GH, Eastman Polyester yellow, - Eastone Blue GFD or Eastman Blue CWB (Manuf. Eastman Kodak Co.), or Sesolin Red Violet FBL (Manuf. Sanoz Corp.).

The electrical potential is shown in Figs. 3 and A- that it is generated by a voltage source 15 which forms a conductive connection between the conductive backing layer 6 and the conductive back layer 4, i.e. the imaging body 1 is sandwiched between electrodes (conductive Back layers 4 · and 6) with different electrical Arranged potential. Alternatively, sine electrical

see cargo on either or both of the tanning and receiving materials, before or after the production of the sandwich structure, according to one of the numerous known methods

f for the induction of a static electric charge in

a material. Static charges can be applied in such a way that the layer or, the Substrate in contact with an electrically charged electrode brings. In addition, one or both layers can be deposited using corona discharge devices. or by using conductive rollers or by friction devices or by other suitable devices, being charged ^ The illustration occurs when charges are applied. The upper bound for the applied Voltage represents the point at which an electrical breakdown of the imaging body 1 occurs, so that the conductivity of the body 1 is sufficient to prevent imagingThis depends on the material used.

If there is a desire to prefabricate a single layer of composite particles by stabilizing the imaging single layer 3 so that the entire imaging body 1 becomes sufficiently rigid to withstand handling, transport and storage, this can be done by . that the composite particles within the image layer 3 using soluble one, acting between the particles of adhesive, "glued ¹ * This is öadurch achieved that one is a small amount of binder which is soluble in the solvent, wherein the lacquers,. - This causes the particles to adhere to the substrate as it dries, and when it is desired to produce a colored image, an insulating liquid such as described above is applied to dissolve the adhesive, thereby releasing the particles for imaging.

Suitable adhesives are, for example, a hydrocarbon polymer with the empirical formula (ΟαΗ ^ ₀ · Ο ^ Η ^ ₀ ) Χ; polychlorinated polyphenyls and other solid or semi-solid resins or polymers that are soluble in hydrocarbon solvents. Typical substances that represent solvents are kerosene, carbon tetrachloride, petroleum ether, silicone oils such as dimethy! Polysiloxanes, long-lived aliphatic hydrocarbon oils such as those that are generally used as transformer oils, trichlorethylene, chlorobenzene, benzene, toluene, xylene, hexane, Acetone, vegetable oils or mixtures thereof, solvents of the FREON range of chlorinated, fluorinated hydrocarbons and, preferably an odorless kerosene fraction.

Since the subtractive color process depends on good cyan, magenta and yellow colors for the materials used in subtractive color imaging, and since the electrically photosensitive pigments determine the color reproduction of a colored original in addition to the dyes, it is preferred that the pigments be natural , have selective, spectral light absorption which is more like the absorption of the colors cyan, magenta and yellow than, for example, the colors red, blue, green, etc. Similarly, it is preferred that the dyes used for the lifelike multicolor reproduction of a color original are representative of cyan It should be noted, however, that the electrically photosensitive pigment is a "sacrificial pigment ¹¹ in the sense that it need not remain on the substrate surface, but solely for the response to electromagnetic radiation to which it is sensitive is, can be used .. In this case, sluggish It only adds the dye present in a

6abe aimed at or, for example, in the case of a color reversal ^ ■

for example, the electrically photosensitive control Pigment ^s address of an imaging composite particle only to red light, but besitr.sn an orange or magenta dye, which is finally imagewise dyed in the substrate wherever red appears in the original.

Although it is not necessary to use charge control agents in the production of an image , in some cases it is desirable to ensure uniform polarity of all particles. Any substance that causes uniform polarity of the particles can be added to the monolayer to control the charge on the composite particles during imaging. Alternatively, the composite particles may contain a dye or pigment which in turn acts as a charge control agent and therefore no additional materials need be added to ensure charge control.

Fig. 5 shows the image of a specific arrangement of the imaging single layer. The imaging takes place through a transparent glass electrode 4 coated with tin oxide and the transmitter substrate 2, which typically consists of a layer of polyester. The light strikes the composite particles of the single layer 3, which particles have been immersed in an insulating liquid such as a kerosene fraction. The incident radiation creates electron-hole pairs in the photosensitive control pigment on the composite particle, resulting in a positively charged particle. When removing the alum: nium-containing electrode receiver layer 5, the positively charged partial particles that have been struck by light adhere

on the negatively charged aluminum receiver layer. Since the arrangement described here is a substrate color process, with exposure through the If the transmitter substrate results, a negative is obtained on the receiver electrode and a positive on the transmitter substrate 2. The polyester donor substrate 2 containing the positive image is then heated, causing the dye to enter the Substrate is colored, which leads to a dye-intensified image in the donor substrate. The one with the Imaged polyester is then washed with trichlorethylene to remove any remaining control pigment and a Remove binder.

It can be seen that the color imaging method is practical can be used indefinitely, as long as the following conditions are observed: Dye and pigment components of the imaging composite particles should be insoluble in the imaging system. Only the dye should be able to be colored either in the donor and / or receiver substrate, unless the image is on an image carrier is transferred and colored on this.

Although the imaging composite particles after Numerous methods can be prepared, the following four methods have been found to be satisfactory proven. These four methods are expediently as spray drying or atomization drying, grinding and heating methods, Jet powder isolation and precipitation method designated.

A conventional device can expediently be used for spray drying, e.g., a laboratory conical type spray dryer can be used. Dye and binder components "Fe of the composite particles can be in one Dispersed solvent for the binder component being. Suitable binders are e.g. Piccolastic Ε-loo, Piccoflex 12o or Piccoflex I00, and suitable solvents are e.g. chloroform or methy la thy lket on. A Particle composed of dye and binder is made by spraying the dispersion through an air brush and collecting the particles on the walls of the aluminum cylinder. The carrier pigment component of the composite Particle is then applied to the surface of the dye-binder core by suitable means such as dispersing of the control pigment in the dye-binder solution before atomizing, dispersing the spray-dried Dye-binder particles in a solution of Piccotex 12ο in petroleum ether (60 to 11ο), or dispersing the Control pigment in the solution and spray drying the dispersion, applied. Spray drying can also be used in this way be that one has both the dye and the carrier pigment components of the composite particle dispersed in a solution of a binder in a solvent prior to spray drying. As mentioned above, finds a satisfactory mapping in composite Particles with a diameter of up to 25 p instead, the preferred range being about 5 to 15 Ji.

The milling and heating method of making composite Particles generally involve the co-milling of dye, control pigment, and binder- particles in a suitable partial solvent for the Binder carrier, such as an odorless kerosene fraction, in a ball mill. The paste obtained is then heated, to apply the dye and the carrier pigment to the tacky or softened binder- The heating times

and! temperatures can vary, the aim being to supply sufficient thermal energy to the binder, so that the fabric and the taxpigiaent come into contact to be adhered to the surface of the binder In general heating in the range of τοπ leads to lminute heating

ο
15o to 2co G to the desired results, although there may be a tendency for fairly large images to be formed, as a result of which a grainy image is obtained in the image. The heating in the range of 85 "to I2O ⁰ C resulting in more satisfactory results in terms of GröSe the zusamt close added particles, wherein heating to temperatures of 85 to 1o5 ⁰ C is preferred. In. General are obtained due to the difference in the relative size between magenta, yellow and cyan particles for a given binder using the relative heat treatment temperatures and heating times given below, particularly good results: cyan particles 10 minutes from tree temperature to 85 C; magenta particles 3 minutes at 1 o o to 1o5 ° C; and yellow particles 5 Minutes at 100 to 105 ° C. In the event that graininess occurs at the lower temperatures of 85 to 12 ° C, it is advantageous to control the size of the binder particles by cutting or jet pulverizing or other comminution processes that have a narrow size distribution the binder component of the composite particles sten.

There can also be other modifying stages in the and heating method for the preparation of composite particles can be applied to the size distribution of the obtained to control composite particles. Such modifications include the application of ultrasonic energy on the dispersing dye, the control pigment and the binder component to these components

to stir the formation of the composite particles, and to heat. Ligroin provides a well-known solvent "at this modified process in that it improves particle growth within a narrow size distribution.

The precipitation method for the preparation of composite particles iv.faSt generally the dispersion of the pigment and dye components in a suitable. Liquid e.g. by grinding in a ball mill In. Petro & over (9o to 12o ° C); heating the dispersion to 9o C to dissolve polyethylene, which is in the ratio of. 1: 1 of polyethylene is added to the total amount of pigment and dye; the precipitation of EöLyäthylens by adding isopropanol from room temperature at a rate of about 10 ml / min, while keeping the temperature of the dispersion at 80 ⁰ G; filtering; or redispersing the filter cake in Dow Corning 200 silicone. Fluid ICS by grinding.

Of course, the aforementioned processes can be used both individually and in combination to produce the composite Particles suitable for the imaging single layer of the present invention can be used.

Λ . Production of the statistically dispersed single layer

A uniform mix, each consisting of the colors cyan, magenta and yellow, is made using the following general processes:

A hydrocarbon suspension of photosensitive control pigment, dye and Piccoflex will Ίοο carrier particles Milled for about 16 to 24 hours using stainless steel balls about 6 mm in diameter.

Because of their size, they are yellow and eyan-colored Control pigment prior to its addition to the particular unit mixture suspensions pre-ground. Each of the cyan », magenta and yellow-colored unit mixes contain the following components (all data in percent by weight):

Stain Cy

Tax pigment (0.50 to 0.75%) »pre-ground ß-phthalocyanine Dye (4-9.7%) »purified estmaneclrfc blue BGLF sluggish (49.7%) »cleaned Piccoflex I00

Lean af arb en

Control pigment (33.5%) - purified 'Haphthol Red B dye (22.2 %) - Sandoz Foron Bubine S-2BPL carrier (44, ^ - %) - purified Piccoflex I00

Gelo-colored

Control pigment (33.3%) - K-2 "-Pyridyl-8-13dioxodinaphtho- <2,

Λ -b; 2 ', 3'-d) -furan-6carboxainid

Dye (22.2%) - Eastman Polyester Yellow 6GLSW Carrier (44.4%) - purified Piccoflex ioo

After the suspension has been ground, it is poured into a flask and heated with stirring under experimentally determined temperature-time conditions. The parameters for the individual unit mixtures are: cyan Λ hour 80 C; yellow 3 hours 90 ° C; and magenta 2 booths 100 ° C. After heating, the unit mixes are cooled by adding an equal volume of room temperature keroinfiaction. (The solvent is previously filtered at room temperature, air-dried and stored until use).

Monochromatic donor materials that are statistically dispersed Single layer are obtained by applying the above-prepared suspensions in a layered manner composed of cyan, magenta or yellow Particles on aluminum foil or polyethylene terephthalate

Slide made. The layer thickness is using controlled by a Kayer doctor blade. It is the Mayer squeegee a solid rod made of stainless steel, the one firmly and rod wound stainless steel wire owns. The recesses between the wires control the thickness of the photosensitive composite simple chi ent die The number of the rod indicates the diameter of the wire in thousandths of an inch (25 µm) - in general an ilayer hook no. 8, corresponding to 2oo um, is used for application the jion layer used on a donor substrate This rod leads to a shift that takes 5 minutes after de ^ a Dries: at 4o ° C <itwa Ίο pm is thick. Many of the composite particles become linear structures of up to connected to 4-0 un length, these structures being by pressure broken into particles of less than 1ο μπ. A Triple genetically from cyan, magenta and yellow composite particles is easily produced by that sau the three simple mixtures to the desired particle - | distribution combined. The triple mix is then carried out in the same way rather manner as above for the monochromatic encoder- I material described, applied, and obtained, statistically! dispersed single layer appears as element 5 of the ELg. Ί to 5-

2. Imaging on the single layer

In general, imaging is used in those described herein randomly disperse single layers under ver. Turn of a translucent tin oxide electrode, like shown in element 4 of Fig. 5, performed. The mapping process flow The precoated and dried imaging single layer can be described as follows: The dried triple blend layer, as described above, on a polyethylene terephthalate film from Made 50 µm thick, it is made in a sufficient amount Solvent, e.g. a kerosene fraction, moistened, see above that in the finally manufactured satidwich arrangement as in Shown in Fig. 5 - no air bubbles in the imaging layer

# ■ ·· # ■

available. An electrical voltage of 5000 volts is applied to the sandwich structure, whereby the aluminum foil and the tin oxide conductive film is used as the two electrodes. The composite particles of the statistical mixed single layer are then with visible; Exposed to light, the exposure times according to the Light intensity lasts about 0.5 to 1 sec. The exposure takes place through the glass and the polyethylene terephthalate substrate. The exposed sandwich is then separated while the tension is still maintained, two with hydrocarbon wetted images obtained, namely (1) the positive image (composite particles), unexposed by Lengths to which they are sensitive) of the original on the polyethylene terephthalate film, and (2) that negative image (compound particles, popular with: wavelengths, to which they are sensitive. are) of the original on the aluminum foil.

Then the polyethylene terephthalate substrate containing the positive image is heated by heating for 3 minutes developed to 175 ° C, with the dyes in the polyester material be dispersed. Eventually, the bud, enhanced by the molecular dispersion of the dye, will be with it a solvent washed to both the opaque photosensitive Remove pigment as well as the scattered binder. The polyester images that result from this process consist of the dyes dissolved in the polyethylene terephthala · material. That is why the pictures are very much permanent and the colors transparent.

Those used in the previous example. Graze dyes specially selected from the point of view that they are molecularly dispersed in the polyester material. The increase the color saturation will be through in this case. Heating the positive Image on the polyethylene terephthalate surface at 175 ° C for a period of about two to four minutes. This coloring heating stage drives to the molecular one. Dispersion of the individual dyes in the polyester material

Microscopic examination of cross sections of the manufactured transparent samples shows that the dyes penetrate to a maximum depth of about Ίο bis15ji or dispersed.

As stated above, the photosensitive control pigment particles and the dispersed binder, Piccoflex loc, are then removed from the polyester image surface by washing with various kinds of organic solvents, e.g. Trichlorethylene, benzene or acetone removed. The image obtained is very durable and the transparent colors are very vivid.

The donor or receiving materials may be present in orm Gewebef what they for the automated imaging and transfer of the image caused by mechanical and electrical means to a suitable substrate, making it suitable. Furthermore, the electrically photosensitive material used can be treated in various ways in order to change various properties of the material. Finally, the above-described adhesive can also be added to the mixtures of one type of composite particle before the imaging body is produced.

The generation of an image with an imaging single layer according to the invention is described above in connection with a three-color transfer process been described; however, it is self-explanatory, also applicable to a monochromatic image. Therefore, a single layer of any of the above-described mixtures with one kind of composite Particles used in the same way for imaging

as above for that of three types of particles existing mixture described, the only difference being that you end up with a monochromatic Image receives.

Claims (10)

Longs for claims 1. Imaging simple layer on a carrier element is arranged.- characterized in that the layer of composite particles (3a) with part- Chen-shaped dye (3b) and photosensitive pigment (3c) in an electrically insulating liquid ". 2. Abbildangs-Einf achschicht according to claim 1, characterized characterized in that it is sandwiched between a donor and a receiving element (2,5). 3. Imaging JSinf achschicht according to claim 1 and / or 2, marked thereby that the together put particles (3a) in addition a binder (3d) for the particulate dye (3b) and the photosensitive Pigment (3c) included. 4. Single imaging layer according to at least one of the claims 1 to 3i characterized by TELEPHONE (O8O) 99 98 63 TELECOPER "own. that the composite particles have an average particle size from "up to 25 µm» preferably 5 to 15 pa » 5. Imaging single layer according to at least one of the Claims 1 to 4, characterized in that that the donor element (2) consists of a translucent Polye st ermaterial. 6. Figure Eiti subject layer after at least one of the Claims 1 to 5 »characterized in that the receiving element (5) is made of a conductive material consists. 7. Imaging single layer after at least one of the Claims 1 to 6, characterized in that the single layer is a randomly distributed composite Contains particles with cyan, yellow, and magenta dyes. 8. Figure single layer according to at least one of the Claims 1 to 7 «characterized in that that at least one of the elements (2.5) in the form of a Tissue is present. 9 · Picture single layer according to at least one of claims Λ to S, characterized ichnet gekennz e, that the imaging single layer additionally contains an adhesive for the composite particles (3a). 10. single image layer according to at least one of claims 1 to 9 *, characterized in that that the insulating liquid has a specific resistance 10
Has a stand of over 10 Ohm'cm.