DE2234314B2 - Process for multi-color drawing - Google Patents

Description

40 continuous operation very annoying.

In DT-AS 22 28 581 a heat-sensitive two-color recording material was proposed.

The invention relates to a method for multiple genes consisting of two layers of two different on-color recording by applying heat drawing materials, an intermediate layer with on a heat-sensitive multicolor recording 45 a polyether as a decolorizing agent for the tion material with several color-developing substance contained in the first layer when exposed to heat There is a recording layer developing different colors and a carrier layer. The intermediate layer layers by means of a heating element. has the task of being formed at low temperatures

It is known that thermosensitive recording color discolor before increasing temperature

materials usually from basic color formers 50 developed the second color in the second layer

and acidic substances such as B. Diphenol in the color is.

loose condition, exist and that application of using such heat-sensitive Heat on the material causing the liquefaction or disintegration of materials, it is difficult to see from two and vaporization of the acidic substance such as B. Diphenol more colors on a single sheet at the known and then to form the liquefied or vaporized 55th copy. In addition, it is not acidic substance is possible with the basic color former, a multicolor display in case of reproduction under Color formation connects. To form the colorless composting process.

Components or components of the recording material are therefore the object of the invention to provide a method

usually available in a single edition sheet for chromatic recording too

stopped and "self-containing system" overall represent 60 which is suitable for multi-color display of figures

called. Another type of heat sensitive such as B. letters, numbers and the like. Suitable that without

The recording material is composed of two sheets of paper - Malerialverdampfung works and works smoothly

set, where a sheet is the first component and no decolorizer interlayer is required,

other sheet contains the second component. The grain object of the invention is a method for

components are placed opposite each other, and 65 multicolor recording by applying

As a result, the action of heat can generate heat on a heat-sensitive multicolor image.

liquefied or vaporized component of the other drawing material rr.with several, when exposed to heat

Component forming a recording over-

«» «Layering by means of a heating element, which shows when the temperature is increased from J ₁ to J.

¹¹ JSSiht that through multi-stage control of the In the above case the ^wa ™ ^e ^ ™ f hih ik T bld

stepped control of the In the above case _f

effective tempera layer I naturally color gf.

one at

. "η F i _E. 3 is a heating element tu,

_{> s}

has direction that is able to between an indicator vor.

Low temperature heating element and a high temperature «.

to switch the temperature heating element

^P This heating element can control the amount of heat and

thereby the heating temperature by control de

Control the current flow in the heating unit. That

heat-sensitive material for the multicolor dress * 5 Multiple layer of Sm material from FIG. 1 to yellow

“If the color is right at low temperature (F ₁ ), it will dy the color. * » _{Ination of}

red due to _color ^. ^^

SiS ^ as evidenced as a result of the

, Cyan and yellow results.

^{Dk f inem}

^ S ^ S ^ n- ^ n ^ mp ^ Sr S

SmSg, which is based on a pad like ζ. Β paper ^^

or film rests, formed, but it can, provided that it is In Γ ι g

Spttiens or a color-forming auxiliary agent ™ t

the edition painting or by embracing it f

^te r ^ lpnnd, ic _te AurnaUmem ^ ia, «*. *; ₃₅ or

Multi-color display contains e.ne warm-sensitive t that

40

45 i g. 3 differentiated _{dn heating element 4}

ί, ™ 1 »ϊother muslims mi. Colors are not necessary. Will »ei

Za

gluing in order of wärmeempfind-'s temperatures ranging from about 60 bs about 16O ⁰ C, is effected. Different colors are produced depending on each specific temperature along the gluing sequence of the heat-sensitive layers in the direction from the first layer to the support layer or the opposite direction. .,

⁶ F i g. 1 shows a cross-sectional view e.nes warm-sensitive material according to the present ^fin ^ ^en; _solid material for the multicolor

^^ C ^ pfindHchen recording.hich- ^ e is from P ^ _{a sequence ver} .

He ^ z "ammeng _{wärmeempfind,} i _i s sma Temperaleimt on.

door ^ bhanet receiving layer of the

^ * 2 _chcn ^P _{On close} mematerials of the present

Frfindune essentially contains a color-forming invention _{containing auxiliary sections S} and

additionally a softening point

fi ⁿ _g ^g; Fig. 2 is a diagram showing the temperature characteristic of each heat-sensitive layer; representing grouping.

^U 1 _ig .4 schematically shows a heating element which is provided with a current control circuit.

F? G. 1 represents a heat-sensitive material, that from edition 1, such as ζ B. Papier and F.lm a heat-sensitive layer 11 2, d.e rests on the support and a heat-sensitive .ehe. Layer I 3 consists, which is sensitive to heat

Layer II is on top, ...

In Fig. 2 are shown heat-color-forming Kcnnlm.en d ,, the above-mentioned heatccmpfindl.chcn Maienais. The heat-sensitive Sch.cht 1 cr / .eugt 6 _a color at a temperature of 7, (not even cmpera uO. While the heat-sensitive «: Sch.cht 1 Λ

, • ■ .h-rhaunt does not form any color, but be. T ₂ larb. u-

au a ne, (crystal violet lactone),

3-l3is - (^ p-aimeinyi-aii <iuu-phenol) phthalide (malalite green lactone) and the like; Leuco-auramine such as B. i-halophenyl derivatives, N-alkyl-halophenyl derivatives, ---- ". \ / - ungcsiiUigle aryl ketones such as:. eton, accton dibenzylidene, anisylidene-Mon (ia / o color Stolte such as p-Diineol-o-carboii ^ äure (methyl), (Oil yellow AAB. ), 4-phenyl-azoylair.'it and the like: Rhodamine-B-lactams such as S ^ p-nitropheny ^ -rhodamine-B-lactam, 3,6'-di- -rhodamine-B-lactam, 3, 6'-diethyl-amino-rhod-

, «Lon u 0 «on" t h> 1-

amine-B-lactam, S ^ '- dimethylamino-rhodamine-B-lactam and the like; Polyarylcarbinols such as bis- (p-dimethyl-aminophenyl) -methanol (Michler's Hydrol), crystal violet carbinol, Malachite green carbinol and the like; Benzoindoline spirophyrans such as ζ. B. 8'-methoxy-benzoindoline-spirophyran, 4,7,8'-trimethoxybenzoindoline spirophyran, o'-chloro-S'-methoxy-benzoindoline spirophyran and the like; Phthalanes such as 1,1-bis- (p-aminophenyl) -phthalan, l, l-bis (p-benzylamino-

Vf - - 1 J-: ι -

phenyl) phthalan, l, l-bis (p-dibenzylaminophenyl) - ίο tes are: phthalan, 1,1-bis (p-N-methyl-anilino-phenyl) -phthalan and the like; and spirophthalans such as ζ. B. 6,6'-Diaminospiro-iphthalan-l ^ '- xanthen), 6,6'-diethyl-amino-spiro- (phthalan-l, 9'-xanthene), 6,6'-dimethyl-amino-spiro- (phthalan-l, 9'-xanthene) and the like

The auxiliary color-forming agents which are used in the present invention are materials which are suitable, thermally with the main color-forming agent to form a conjugated system to respond, such as B. phenolic compounds, phenolic derivatives, phenolic plastics and the like.

Representative auxiliary color-forming agents common to the main color-forming agents mentioned above are suitable are: 4-tert-butyl-phenol, 4-ter-

Control of the farfo-forming temperature range can be used. The softening point controlling agent should be mutually soluble with the main color forming agent and / or the auxiliary color forming agent in order to lower the softening point. There are, for example, materials with a low melting point, higher fatty acids and crystalline, solid plasticizers.
Representative materials with low melting point

a) amides such 2. B. 9,12-octadecanamide, 9-Octadecanarnid, octadecanamide, hexadecane amide Tetradecanamiil, dodecanamide, decanamide, Octanamide, Hexanamide u., etc .;

b) paraffins, for example chlorinated paraffins;

c) derivatives of fatty acids, for example methyl hydroxy stearate, Glyderol-tri-l ^ -hydroxy-stearate, partially hydrogenated castor oil.

Representative higher fatty acids are those with 12 to 20 carbon atoms and melting points Range from 50 to 150 ° C, for example lauric acid, Palmitic acid, stearic acid, myristic acid and the like.

Representative crystalline solid plasticizers are

tertiary amylphenol 4-phenyl-phenol, 4-4'-isopropylidene-25 diphenylphthalaH (DPP), dichlorohexylphthalate bis- (2-chlorophenol), 4-4'-isopropylidene-bis- (2-me- (DCHP), ethylene glycol dibenzoate (EGDB), dimethylethylphenol), 4,4'-isopropylidene-bis- (2-tert-butyl-isophthalate (DMIP) and the like.

phenol), 4,4'-secondary-butylidene-bis- (2-methyl-pne- as the binder used in the present invention

nol), 2-2'-Dihydroxydiphenyl, 4,4'-Sckundäres-Buty- can be used, methyl cellulose, gummiliden-diphenol, 4-tertiary-octyl-cathechol, bis-phenols, arabic, gelatin, sodium alginate, casein, Zinc-4'-hydroxy-acetophenone, methyl-4-hydroxy-benzoate, caseinate, sodium carboxymethyl cellulose, polyvinyl · · 4-hydroxy-diphenoxide, «-naphthol, ^ -naphthol and alcohol, pectin, polyvinylpyrrolidone, starch and their phenol-formaldehyde -Condensation products of the No derivatives, copolymers of styrene and maleic acid volack type, phenol-formaldehyde condensation anhydride, copolymers of polyethylene and maleic products of the resol type and modified phenolic acid anhydride, copolymers of polyvinylpyrrolidone plastics and the like. These phenolic materials and maleic anhydride, polyacrylate and their Coweisen melting points ranging from about 60 to polymers, copolymers of styrene and butadiene, Emul 150 ⁰ C. It is preferable to mention the material having ions of polyvinyl chloride, polymethyl acrylate and low melting point or softening point in which polyvinyl acetate and the like are mentioned. Among them, the heat-sensitive layer which is close to the heating element 40, gum arabic, zinc caseinate, copolymers to be used, and the material with higher styrene and maleic anhydride and copolymers of melting or softening point in a heat em- styrene and butadiene are particularly effective. The color-sensitive layer, which is further formed by the heating element, which is removed by combining the representative elements, is to be used. main color-forming agents, isl

The softening point control agent can be shown in the table below:

Color forming Color image cndes colour multiple layers Main agent (I) Main agent (II) a layer violet Crystal violet Rhodamine Red Lactone (C. V. L.) Lactone (RL) bluish green Malachite green green Lactone (MGL) green Leuco-auramin (LA) yellow yellow Rhodamine Lactone (R. L.) Malachite green Red Lactone (MGL) orange Leuco-auramin (LA) Red yellowish green Malachite green lactone Leuco-auramin (LA) green (M. G. L.) black. "(purple) Crystal violet Rhodamine Red Lactone (C. V. L.) Lactone (RL) Leuco-auramin (LA)

(Bisphenol A is used as a color-forming auxiliary agent)

7 8

The feature of the present invention consists in that printing on drawings or displays on sensitive material for two-color display on the same recording sheet or tape in different colors using a heating element has been achieved Control of the Heiztempe- relatively low temperature (about 60 to 110 ⁰ C) beratur the heating element can be formed. For 5 acts to create a red master. In contrast to the example, according to the present invention, if the printing was carried out at a relatively high temperature (110 to 160 ° C), a process with a blue color and was carried out in a table-top calculating device get the answer and sum clear purple pattern. In each case it was indicated with red color, and furthermore the current flow can be applied during 5 to 20 m · see. Thermal printing machine or copier from io

important sentence can be printed with red color, if- Example 2
rend less important sentences are printed in blue

can be. Even with conventional writing, high-temperature color-forming composition: 20-part

machines, a two-color display is used, le CVL and 10 parts of a copolymer of styrene and

however, mechanical typewriters are noisy, and maleic anhydride has been mixed up and during

only predetermined numbers or letters can be milled for 1 hour until the particle size is 0.5 to

to be printed. In contrast, the color may have reached 2 microns. On the other hand, there were 60 parts

one part or one half of each letter or bisphenol A and 10 parts of a copolymer of

Number can be changed according to the present invention. Styrene and maleic anhydride mixed and

For example, a heating element is used that grinds for 1 hour until the particle size of the

is composed of a linear matrix that bisphenol A reached 1 to 3 microns. The resulting

Containing many small heating parts arranged in a row, two animal compositions were stirring

and the heating element is mixed in one of the linear dimensions and placed on paper (thickness 60 microns) in

trix vertical direction, and each of a thickness of 2 to 5 microns (when dry)

Current supplied to the small heating part is applied accordingly by means of a wire bar or billet,

controlled according to the pattern. As a result, a multi-low temperature color-forming composition can:

Farb-Mustcr recorded in place of 20 parts of RL and 10 parts of a copolymer

Letters or numbers divided into individual points. Styrene and maleic anhydride were mixed and

is. Such multicolored dot patterns can be ground for 1 hour until the RL particles

conventional mechanical typewriters had not reached 30 in size from 0.5 to 2 microns,

getting produced. 55 parts of bisphenol A, 10 parts of a copolymer

The following examples serve to illustrate styrene and maleic anhydride and 5 parts of

Solution of the invention, but the invention is not Myristic acid were mixed and ground up

limited to this. In the examples, parts in the particle size of bisphenol A are 1 to 2 microns

Weights are expressed unless otherwise specified. 35 wore.

. -ti The resulting two compositions were

Example 1 thoroughly mixed together and on the how

High-temperature color-forming layer: 20 parts of the high-temperature color-forming stable violet-lactone (CVL) obtained above and 10 parts of a copoly layer in a thickness of 2 to 5 microns (after more than styrene and maleic anhydride were dried) by means of of a wire bar, mixed, and milled for one hour until the CVL part - The resulting thermosensitive recording - was 0.5 to 2 microns in size. Material was subjected to a pressure test as mentioned in the above 60 parts of phenolic resin and 10 parts of a copoly- Example 1, to produce a clear blue color of styrene and maleic anhydride were violet,
mixed in the form of a solution and mixed for 1 hour 45 _n . -,,
ground until the particles of the phenolic resin Example i
reached a size of 2 to 3 microns. Then high temperature color-forming composition: The above-mentioned two composite high-temperature color-forming layer, which was mixed as in the legs and obtained on a pad (60 microns thick) game 1, was used,
in a thickness of 2 to 5 microns (when dry) 50 Low temperature - color-forming composition: applied by means of a wire bar or billet. 20 parts of RL and 10 parts of a copolymer

Low-temperature color-forming layer: 20 parts of styrene and maleic anhydride were powdered

Rhodamine lactone (RL) and 10 parts of a copolymer and grind for 1 hour until the particles

of styrene and maleic anhydride the size of the RL had reached 0.5 to 2 microns,

mixes and for 1 hour, until the RL particles are a 55 55 parts phenolic resin, 10 parts of a copoly-

Reached 0.5 to 2 microns in size, milled. mers of styrene and maleic anhydride unc

A mixture of 55 parts of phenolic resin, 5 parts of ethylene glycol dibenzoate (EGDB) was used

10 parts of a copolymer of styrene and maleic mixed and ground until the particle size de:

acid anhydride and 5 parts of myristic acid, phenolic resin was 1 to 3 microns,

milled for 1 hour until the phenol art 60 The resulting two components were unde;

resin was 1 to 2 microns in size. Stir mixed and on the high temperature color

Then the two grain-forming layers obtained above were 2 to 5 microns (after drying

Positions mixed and applied to the high temperature thick using a wire knot,

color image cndc layer obtained as above. The resulting heat-sensitive sheet for dl ·

became 2 to 5 microns thick (when dry) by means of 65 multicolor formation which had low tack

a wire bar or billet applied to a pressure test, as in Example 1 be

a heat-sensitive recording material for the wrote, subjected to a clear two-color

Generate two color displays. To generate education.

9 10

Low temperature coloring layer: 20 parts

B e i s ρ i e 1 4 RL and 10 parts of a copolymer of styrene and

High temperature color-forming composition: The butadiene was mixed and held for 1 hour

High-temperature color-forming layer, obtained after grinding until the size of the RL particles is 1 to 2 Mi

Rpknipl 2 was used 5 crown was. A mixture of 55 parts of bisphenol A.

^ SääÄiSr ^ faA-forming composition: and 10 parts of a copolymer of styrene and I But *

20 parts of RL and 10 parts of a copolymer of diene and 5 parts of myristic acid were mixed and

Styrene and maleic anhydride were mixed and ground until the particle size of the bisphenol a

and grind for 1 hour until the particle size was 0.5 to 2 microns then

size of RL was 0.5 to 2 microns. «Became the two compositions obtained above

55 parts of bisphenol A, 10 parts of a copolymer mixed, stirred and heated to the high temperature tarD

of styrene and maleic anhydride and 5 parts of the forming layer coated or coated, uas

EGDB were mixed and ground until the partial printing was carried out as in Example 1, una

The bisphenol A size was 1 to 3 microns. thereafter a clear red pattern was obtained.

The resulting two 15 B e i s ρ i e 1 7

Compositions were mixed with stirring and

on the high-temperature, high-temperature color-forming layer obtained as above: The nocn-

color-forming layer in a thickness of 2 to 5 microns temperature-color-forming layer, as in Example 3 (after drying) generated by means of a wire baton was used, The resulting heat-sensitive sheet 20 low-temperature color-forming layer: 20 leiie possessed an adhesion similar to that in RL and 10 parts of a copolymer of styrene and Example 3 was similar to a pressure test in butadiene and mixed for 1 hour In a similar manner as in Example 1, subjected to a ground until the size of the RL particles is 0.5 to clearer and more bluish-purple pattern than was 2 microns. 55 parts phenolic resin and Example 3 was obtained. 25 10 parts of a copolymer of styrene and butadiene

and 5 parts EGDB were mixed and ground,

Example 5 bis the size of the phenolic resin particles 1 bis

High temperature color-forming layer: 20 parts CVL was 2 microns. Then the two were received and 10 parts of a copolymer of styrene and bene compositions mixed and stirred and on The tadiene was mixed and the high-temperature color-forming layer was ground for 1 hour until the particle size of the CVL was 0.5 to 2 mixed or coated and crowned according to Example 1 fraud. prints. The resulting print was good and not

60 parts of phenolic resin and 10 parts of one, sticky.

Copolymers of styrene and butadiene were used

mixes and grind for 1 hour until the partial 35

phenolic resin particle size 1 to 3 microns high temperature color-forming layer: the high fraud, temperature-color-forming layer, which in Example 6

The resulting two compositions were hold was used mixed with stirring and in Example 1 similar low-temperature color-forming layer: 20 parts

Way applied or coated. 40 RL and 10 parts of a copolymer of styrene and

Low temperature color-forming composition: butadiene were mixed and held for 1 hour 20 parts of RL and 10 parts of a copolymer of ground until the size of the RL particles is 0.5 to Styrene and butadiene were mixed and while was 2 microns. 55 parts of bisphenol A and 10 parts

Mill for 1 hour until the particle size RL 0.5 to a copolymer of styrene and butadiene and

Was 2 microns. 45 5 parts of EGDB were mixed and ground, 55 parts of phenolic resin, 10 parts of a copoly- until the size of the bisphenol A was 1 to 2 microns-

mers of styrene and butadiene and 5 parts of then became the two grain myristic acid obtained above were mixed and mixed and stirred for 1 hour positions and on the high grind, until the particle size of the phenol-artificial-temperature-color-forming layer according to Example 1 is resin was 0.1-0.5 microns. 50 layered. As a result of the pressure test by dai

The resulting two grain positions were method of Example 1, good two-color mixed with stirring and applied to the high-temperature color-forming layer obtained as obtained above sheet with red and violet, and then subjected to a printing test as in Example 9 1 in order to obtain a sharp and highly transparent 55 high temperature color-forming layer: 20 parts of the pattern. lachite green lactone (MGL) and 10 parts of a copoly Example 6 kidneys of styrene and maleic anhydride ^wu "k"

for 1 hour until the size of the MuL

High temperature color-forming layer: 20 parts of CVL particles 0.5 to 2 microns. 60 parts of phenol and 10 parts of a copolymer of styrene and buta-60 resin and 10 parts of a styrene and maleic acid diene were milled for 1 hour until the CVL anhydride copolymers were mixed and when particles reached a size of 0.5 to 2 microns . Mill for 1 hour until the size of the pheno 60 parts of bisphenol A and 10 parts of a copolymeric synthetic resin particles 1 to 2 microns were mixed with styrene and butadiene, and then the composites obtained above were ground until the bisphenol Particles with a size of 1 6 ₅ ions are mixed and placed on a film layer (60 micro to 2 microns. Subsequently, the pre-thick) in a thickness of ~> to 5 microns (two compositions obtained according to Trort are mixed and mixed) by means of a Wire bar applied, applied according to Example 1 or coated. Low temperature color image cndc layer: It was

the low-temperature color-forming layer prepared as in Example 1 was used.

This was coated to a thickness of 2 to 5 microns (when dry). As a result of the pressure test following the procedure of Example 1, two colors, green and purple, were obtained.

Example 10

High-temperature color-forming layer: The high-temperature color-forming layer Layer obtained as in Example 6 was used.

Low-temperature color-forming layer: The low-temperature color-forming layer Layer was made according to the procedure of Example 6, except that malachite green lactone was used in place of RL, manufactured.

In a manner similar to Example 1, a printing sheet was made manufactured. The resulting sheet was subjected to a printing test as in Example 1 to form blue and bluish-green pattern.

Example 11

20 parts of leuco-auramine (LA) and 10 parts of a styrene and butadiene copolymer were during Mill for 1 hour until the LA particle size was 0.5 to 2 microns. 60 parts phenolic resin and 10 parts of a styrene and butadiene copolymer were mixed and milled for 1 hour, until the phenolic resin particles reached 1 to 2 microns in size. The two obtained above Compositions were mixed and printed on 60 micron paper 2 to 5 microns thick (after Drying). Then it became the high temperature color-forming Layer obtained as in Example 1 on the color-forming layer obtained above Layer applied and further the low-temperature color-forming layer, obtained as in Example 1, layered on top. The thickness of each layer was the same as that of Example 1.

The resultant heat-sensitive, multi-color recording element has a pressure test at a low temperature between 60 and 8O ⁰ C, at a medium temperature between 80 and 110 ° C and at high temperature 110-160 ⁰ C to form clear patterns in Red, Blue and Black subjected.

Examples

The procedure of Example 1 was repeated except that N- (2,5-dichlorophenyl) leucoauramine was used was used in place of crystal violet lactone, and the printing was as in Example 1 carried out. As a result, prints of black-violet and bluish-black were obtained.

Example 13

Using the procedure of Example 6 except that N-benzoyl-auramine was used in place of CVL was used, reddish orange and yellow prints were obtained.

For example, 14

Using the procedure of Example 9. with

Exception that N- (p-nitrophenyl) rhodamine-B-lactam is used instead of malachite green lactone reddish-pink and black-green prints were obtained.

Example 15

Using the procedure of Example 1, with

Exception that instead of crystal violet lactone 8'-methoxybenzoindolinospiropyran and / 3-naphtho!

was used in place of phenolic resin.

red and brownish-black prints were obtained,

1 sheet of drawings

Claims (6)

1 J2 are averaged. The latter system is known as the "über-patent claims: mediation system". These heat-sensitive recording materials 1. Processes for multicolor recording have found wide application in the reproduction of documents by the application of heat to a heat sensor. Further, a heating element, a multi-color sensitive recording material using a miniature semiconductor, has recently been developed several different when exposed to heat. This heating element is built into a table top-color developing recording layer arithmetic device and in a high-speed pressure means of a heating element, thereby machine as a recording head,
indicates that by means of multi-level control, conventional temperatures can be developed for all colors whose heat-sensitive recording materials are used for the usual color formation temperatures of the effective copying, provided that it is reached in geTemperaturen or exceeded. is appropriately improved. However, it is 2. The method according to claim 1, characterized in 15 term recording heads, unlike in the area of the above, that the recording layers in the borrowed copy, particularly preferably the important ones Order of the color formation temperatures of the in dates and figures from the others by use to distinguish the color-forming materials contained in them on another color, a carrier are applied. From US-PS 34 34 878 a recording or 3. The method as claimed in claim 2, characterized in that the recording material is known which has a first conductive one indicates that the color forming material is at least one layer on a base, an electrically conductive one a phenolic compound and one to react with the second layer with a colorant of good heat this forming a conjugate system and a material provided thereon Contains capable coloring material. includes that for color formation by thermal reac- 4. The method as claimed in claim 3, characterized in that it is enabled and finally a white electrical one shows that the coloring material has a basic ma-conductive layer on the surface. Both the Oberterial with a color-forming group. surface layer as well as the coloring or color-forming 5. The method according to claim 4, characterized in that the layer can be volatilized by heat, shows that the basic material is called diaryl- This well-known principle of color recording or phthalides, leuco auramines, arylauramines, 30 colored registration based on the selective separation «, /? - unsaturated aryl ketones, basic mono-vaporization of the undesired cover azo dyes, Rhodamine B lactams, polyaryl layers. For this purpose electrically leicarbinolen, Benzoindolinspiropyranen, Phthalanen tende layers are provided, which with current passage and spirophthalanes is selected. be heated and volatilized accordingly. the 6. The method according to claim 2, characterized in that the strength and duration of the current must be marked shows that the color formation temperatures are regulated very precisely in this case and see 60 and 160 ° C to be selected. an undesired hold of the stylus inevitably leads to volatilize all layers. The evaporation of the material that takes place here is particularly in the