DE2051988C - Heat sensitive stencil sheet - Google Patents

Description

Since the resin components used to form an ink-impermeable film are generally soluble in an organic solvent such as ketone, lister, chlorinated hydrocarbon, nitro paraffin and the like, the heat-sensitive compounds and heat-fusible compounds to be added to such resin solutions should have appropriate solubility properties. However, they can be insoluble in such solvents, but must then be mixed in finely divided form with the resin solutions. Henceforth should both connection types have the ability when heated to about 80 to about 180 ⁰ C, that is within the temperature range in which the ink-impermeable film is perforated by infrared irradiation or exposure is. To develop and melt color.

In other words, these two connection types should in terms of promoting that the achievement Stencil sheet after covering with an original and exposure at the same time with its perforation in the areas congruent with the original image a visible color image of the original in possibly more pronounced color depth than this should deliver, in the printing ink-impermeable FÜL: uniform spread out and be able to either color

ίο to develop or become transparent and thereby to effect this color development within a temperature range identical to that for the perforation necessary matches or comes close to it. In Table I below are batch solutions for obtaining a printing ink impermeable according to the invention Films enumerated.

Table 1

Solution no Thermoplastic resin Plasticizers solvent 1 Polyvinyl acetate Butyl phthalate Methanol 2 Polystyrene (MW <100,000) Dimethyl phthalate _r chlorinated paraffin toluene 3 Cell silose acetate butyrate hydrogenated methyl abietate acetone 4th Cellulose acetate propionate Dioctyl phthalate Ethyl acetate 5 Ethyl cellulose polyester Ethyl acetate 6th Vinyl chloride-vinyl acetate copolymer Petroleum-aromatic hydrocarbon toluene 7th dertaled rubber male Dioctyl phthalate Ethyl acetate acid resin 8th Coumarone resin Dimethyl phthalate Ethyl acetate 9 Acrylic resin hydrogenated paraffin toluene 10 Methacrylic resin Tricresyl phosphate Ethyl acetate 11th Cellulose acetate Dibutyl adipate acetone 12th Methyl cellulose Dimethyl phthalate Methanol

Instead of the plasticizers listed in the table above, each of the following substances is also used can be used for the same purpose:

Abietic acid derivatives

Adipic acid derivatives

Azelaic acid derivatives

Benzoic acid derivatives

Biphenyl derivatives

Caprylic acid derivatives

Citric acid derivatives

Epoxy derivatives

Ether derivatives

Ethylenediamine derivatives

Formal

Fumaric acid derivatives

Glycerine derivatives

Glycol derivatives

Petroleum derivatives

Isobutyric acid derivatives

Lauric acid derivatives

Maleic acid derivatives

Mellitate

Myristic acid derivatives

Nitrile derivatives Oleic acid derivatives Palmitic acid derivatives Paraffin derivatives Pelargonic acid derivatives Pentaerythritol derivatives Phenoxy plasticizers Phosphoric acid derivatives phthalic acid derivatives polyester

Ricinoleic acid derivatives Sebacic acid derivatives Stearic acid derivatives styrene derivatives succinic acid derivatives Sucrose derivatives sulfonic acid derivatives tall oil derivatives Tartaric acid derivatives

From the point of view of thermal perforability, the mixing ratio between plasticizer and thermoplastic resin - expressed in parts by weight - should be between about 0.1: 1 and about 20: 1 lip · tf> n in these make-up solutions

If only the visibly reactive, thermosensitive compound is added to the preparation solution for the ink-impermeable film, it does not need the same concentration as that of the color-developable, thermosensitive layer of a thermosensitive copying material, but desirably in an amount corresponding to about 0.1 to about 1 , 0 parts by weight per 1 part by weight of resin-fused substance are used in the solution, but at the same time it is essential that their amount in the final film layer on the carrier paper does not exceed 15 g / m ² . Furthermore, the batch solution containing it and the resin should be applied to the paper in such an amount that the amount of solids remaining on it ^{weighs about 3 to about 50 g / m 2} , because then it is easy to determine the correct amount of exposure to achieve a visible color image. If the amount applied is less than about 3 g, the requirements for the clarity of the perforated image, which are used for recognizing the correct amount of exposure in stencil production, cannot be achieved. If the layer application is insufficient, pinhole erasers also occur in the stencil sheet film, and the stencils obtained with such defective stencil sheets produce rather blotchy prints during the subsequent printing process. Wtnn on the other hand too much,

ie more than 50 g / m ^{2 of} film solids is applied, the required imaging, which is intended to serve as a standard for achieving suitable perforation, did not occur.

With regard to the visibly reacting, heat-sensitive component which can be used according to the invention can be found in the literature on Wärmeemplindliclies Copying material and the like numerous references. The following are known compounds of these some suitable for the present purpose are listed:

a) Complex compounds that change color in the temperature range between 50 and 120 C. They include, for example, hexamethylenetrainine cobalt chloride (CoCI ₂ ^ C ₆ Hj ₂ N ₁ - 1 OH ₂ O) with a color change from yellow to red,

Hexamethylenetetramine-potassium iodide (light yellow-red), hexamethylenetetramine cobalt bromide (light yellow-red),

Hexamethylene tetramine nickel chloride (light green), hexamethylene tetramine cobalt nitrate or sulphate and hexamethylenetetramine nickel nitral or sulfate.

b) Mixtures of substances consisting essentially of a compound melting between 100 and 80 ° C with a secondary alcoholic hydroxyl radical, sulfur and an inorganic one Metal salt or metal acetate.

Its hydroxyl-containing components include, for example, benzoin compounds such as benzoin, 2-methoxybenzoin, 4-chlorobenzoin, 4-dimethylaminobenzoin and 2-chloro-4'-dimethylaminobenzoin, C'arbinols, such as diphenylcarbinol, phenol compounds, such as resorcinol, pyrogallol, 3-hydri .- \ ytoluene-4-sulfonic acid, 4-Nii: roresorcinol and 4,6-dibromoresorcinol, aliphatic polyhydric alcohols such as erythritol, sorbitol, galactose, maltose, mannitol and sucrose.

Suitable metal components are, for example, those which react with sulfur to form colored sulfides Metal compounds, such as the sulfates, nitrates, carbonates and acetates of copper, Lead, tin, molybdenum, cobalt, chromium, nickel, manganese, titanium, antimony, rhodium, mercury, Iron, barium, bismuth, arsenic, magnesium, indium and iridium.

45

c) Substance mixtures consisting essentially of a hydroxyl-containing compound as in b), sulfur and a complex bond according to a).

d) Mixtures of substances consisting essentially of one carbohydrate such as sucrose, fructose, galactose '° and starch and a dehydrating agent such as sulfuric acid, acetic anhydride, anhydrous Zinc chloride and p-toluene sulfonic acid.

In addition to these aforementioned compounds and substance mixtures, the following are also suitable heat-coloring substance mixtures:

e) Mixtures of substances from a single iron salt a long chain fatty acid such as iron stearate and myristate, and on the other hand phenol or one Phenolic acid, such as tannic acid, bile acid and ammonium salicylate,

f) mixtures of substances consisting essentially on the one hand of a heavy metal salt of an organic acid, such as B. nickel, cobalt, lead, copper, iron, mercury and silver salts of vinegar, slcurinulide Palmilicic acid and, on the other hand, either

35

40 an alkaline earth metal sulfide such as calcium, strontium and barium sulfide or an organic sliding compound such as s-diphenyl carbazide and diphenyl carbazone,

g) Mixtures of substances consisting of <m essential on the one hand a heavy metal oxalate, such as silver, lead. Mercury and thorium oxalate, and on the other hand a sulfur-containing compound such as sodium tetrathionate, sodium thiosulfate and thiourea,

h) Substance mixtures consisting essentially of a fatty acid iron (III) salt, such as iron (III) stearate, and on the other hand an aromatic polyhydroxyl compound such as 3,4-dihydroxytetraphenylmethane,

1) Substance mixtures consisting essentially of one side Ldelmetallsal / an organic one. Acid. like silver and Queci, silver oxalate and on the other hand an organic polyhydroxyl compound such as polyhydroxyl alcohol, glycerin and CJlycol.

j) mixtures of substances consisting essentially on the one hand of a Fdelmelall salt of an organic acid, such as silver behenate or stearate and others aromatic reducing compound. like protocatechic acid. Spiroindane and hydroquinone,

k) Substance mixtures consisting essentially on the one hand of a fatty acid iron salt, such as iron (III) pelargonate and laurate, and on the other hand a thio or isothio:> emicarbazide derivative,

I) Mixtures of substances consisting essentially on the one hand of a lead salt of an organic acid, such as blcicapronate, -pelargonate and -beheiiat, and on the other hand a thiourea compound such as ethylene thiourea and N-dodecylurea,

m) mixtures of substances consisting essentially of a heavy metal salt of a higher fatty acid, such as Iron (lll) and copper tearate, and on the other hand Zinc dialkyl thiocarbamate,

n) mixtures of substances, such as B. resorcinol _t nitroso compounds that form an oxazine dye, or those that produce an azo dye.

The visibly reactive, heat-sensitive component useful in the present invention is natural not limited to the aforementioned examples; rather, every compound or mixture of substances is useful that can thermally release a polyvalent metal cation and in general is used in thermal copying technology. These include: For example, the aforementioned heavy metal salts an organic acid or its combination with an organic reducing agent, a sulfur compound or an amino compound and any individual compound that is thermally a color develops.

The heat-fusible compounds which can additionally be used according to the invention include, for example, metal salts of saturated or unsaturated higher, ie C, QC ₂₂ -fatty acids, such as stearic, palmitic, lauric, myrisic, oleic, erucic and behenic acid, etc., of to which at least one of the resin solution forming the ink impermeable film is added. As a metal component grain

S "

7 8

men - on the periodic table of the elements In the sense of the invention, it is also the film-related - metals of group II. such as calcium, forming resin solution ajch still a small amount of zinc, cadmium, magnesium, etc., lead as group IV - a dye, like crystal violet, fuel black, metal, manganese as group VIII metal, iron, cobalt, Sudan red, rillanl blue or the like, to add a certain basic tint to the nickel etc. as group VIll melall as well as Kapfcr 5 stencil sheet as a group -I-metal into consideration. Metal salts of give, which then, when correctly coordinated with the fatty acids with fewer carbon atoms than caprine - later color of the perforation pattern, the latter are still acidic (C _e H _ie COOH) because of their unpleasant nature.

Odor hardly usable in practice. The advantage of using the inventive method with metal salts of fatty acids with more stencil sheets for stencil production is carbon atoms than behenic acid (C ₂₁ H ₄₃ COOH) so, to repeat it, is that you do not work, but are best suited the salts of two fatty acids with up to 22 carbon atoms only because of the easy comparability. These see the original image and the resulting perforation heat-fusible connections show the melt image with the naked eye at the correct infrared exposure point between 70 and 15CTC. »5 determine the extent, but also from the

Calculated on 1 part by weight of solid resin substance, the clarity of the stencil created, one can draw conclusions about the clarity of the visibly reactive, baren color image heat-sensitive connection as well as - in case you can later pull stencil prints. Different also used - in terms of the heat-melting compound, 0.1 to about 1.0 part by weight can be used during stencil binding. In the case of a joint position with the naked eye, the respective state When used, it is expedient to choose a decrease in the clarity of the perforation image those compounds that do not interrelate insufficient or excessive infrared exposure react. If one can easily ascertain beyond the specified upper limit, and furthermore the additional limit itself is able to go beyond, the perforating ability suffers »: template in its later practical use in the production of stencils and makes it more difficult to use prints with a clarity that matches that of the Perforate, and if the value falls below the stencil image below. Thus, the boundary removes, on the other hand, the clarity of the perforation find- ing the imperfection of the previous shield. And it's hard to get the right blister leaves that you get the right amount of exposure determine the extent of the clearing. If the resin is too low - only after completion and the actual content in use may arise in the printing ink impermeability - the stencil could estimate film pinholes, and if the resin is too high content on the other hand decreases in turn the perforation of preferred embodiments explained in more detail, ability. Therefore one puts them on the paper without being limited to them, applied amount of the film-forming solution with. . . . . its two or three specified components so 35 υ e 1 s ρ 1 e 1 1 A resin, referred to below as "solution a)" - 3 to 50 g per square meter of paper solution consisted of a solution of 5 g of commercial space. usual cellulose acetate butyrate in 50 ml acetone, the

If you use the template sheet according to the invention 10 g of commercially available halogenated abietic acid

in contact with an original by exposure to the 4 ° ester and 5 g of mineral oil (aniline point 97 ° Q added

When converting stencil, the image will be congruent.

Film areas perforated and developed at the same time Another, hereinafter referred to as “solution b)”, refers to the heat-sensitive solution of the visibly reacting, heat-sensitive component color, which is present in the perforated area, and the colored sensitive compound consisted of 50 ml of acetone in Melt collects close to the edges of the per- 45 the 5 g of zinc stearate by working in for an hour forged district, so that a sharp, from the ball mill were dispersed. Perforation presents an existing color image. The two solutions were mixed together, Clarity and color clarity of this picture are still and with this mixed solution a 9 g / m * weight, better if the film also contained the second, thermally melt-porous, thin paper made mainly of Manilabare compound. Since the very fine particles of the hemp fibers are impregnated and thus adhere to the paper fibers with a printing-colored melt, a paint-impermeable film can be coated. The coating one the perforated area with the naked eye amount was regulated in such a way that on 1 qua just as sharp as pictures, characters and representations, dry meter paper about 10 g total dry strength recognize ordinary prints. Repeatedly substance and 2 g heat-sensitive compound so lets the heat-sensitive compound come for itself.

alone or together with the heat-fusible A-4-large cut of this stencil paper

The connection in the original image-congruent film was assigned an original on the film side, which

district of the stencil sheet following the print image in the shorter infrared range lying beam

Melting and perforating that which was able to absorb in the film as the main part, and then of de component contained, thermoplastic resin 60 paper side forth in a commercially available copier

a colored melt, which may have been intensified, is removed for about 4 seconds with such sirahlun

stand, which is exposed closely to the contours of the perforation. So you got a red-colored perforation!

adjacent to the picture collects and tin part of the picture, which is clear from a pink underground at

Perforated area located paper fibers an- nob. During the perforation voi adheres, whereby a possibly very sharp output can easily determine the correct amount of irradiation:

The embossed color image is recognizable to the naked eye by step-by-step exposure

without the perforated and repeated as often as the consideration of the j (

District obstructs the passage of printing inks. because the resulting color image is required

ίο

let. The stencil obtained in this way delivered in practical use in eiher.i commercially available transfer printers cine Large number of sharply engraved prints true to the original.

For comparison, the same carrier paper was used and the same resin solution, but without a visibly reactive, heat-sensitive compound contained four stencil sheets, also the size of B-4, and about 3, 4, 5 in the same copier and exposed for 6 seconds. The resulting perforation images were hardly recognizable, and you couldn't possibly tell which exposure was the right one. Practically used as a transfer stencil, only the stencil produced by exposure for 4 seconds gave clear and true-to-original quality Prints, and all the rest made only blurred prints.

Example 2

Example 1 was repeated with the modification that the solution a) this time from a solution of 5 g of commercially available cellulose acetate propionate in 50 ml of ethyl acetate to which 10 g of halogenated abietic acid ester according to Example 1 and 2 g of mineral oil were added, and the solution b) from a through 18 hours of ball milling obtained a dispersion of 8 g of the hexpmethylenetetramine-cobalt chloride complex in 50 ml of ethyl acetate. The infrared exposure gave a clear, colored perforation image in blue on a milky white background, and the prints obtained with the stencil obtained in this way corresponded completely to this perforation image.
5

Example 3

Example 1 was repeated again with the exception that the! Umbildende mixture from the

ίο solution a) according to example 1 and a solution b) in the form of a dispersion of 4 g zinc stearate, 0.2 g diphenylcarbazone and 4 g calcium stearate in 50 ml Acetone consisted. The stencil sheet obtained in this way gave a red-colored per-

IS foration picture, which is not only more pronounced than in the Example 1 was colored but also made it extremely easy to determine the correct amount of exposure. the The stencil produced in this way had outstanding transfer printing capabilities.

Example 4

In the manner described in Example 1, several stencil sheets were produced which extend through the composition of their film layer differed and accordingly in the infrared exposure with adjacent Original different colored perforation images provided. The following is about this Table II information.

Together
setting the
Resin component
as in the example table II Solution
medium each
SOMI Color of
Perforations
picture Movie
educational
solution 1 Visibly responsive, warmth
delicate connection Heat fusible
connection acetone black A. Zinc acetate 5.5 g Manganese stearate 3 g Benzoin 1 g 1 Sulfur 0.5 g Ethyl acetate Dark brown B. Sucrose 3 g Cadmium stearate 2 g 1 p-toluenesulfonic acid 3 g acetone blue C. Hexamethylenetetramine Zinc stearate 3 g Cobalt chloride complex 2 salt 4 g Tetrachlor black D. as in A Cadmium palnutate carbon 2 3g chloroform Dark brown E. 2 as in B. Copper laurylate 3 g acetone blue F. as in C Silver behenate 3 g

All six stencil sheets delivered - in contrast to control stencil sheets without an additive of heat-sensitive compound - clear, high-contrast Perforation images with which one can easily find the correct exposure time when making stencils could determine.

Equally good results were obtained when the heat-fusible compound was used instead of ii Substances given in tables

Cobalt, zinc, lead or magncsium laurylate Zinc, cobalt or cadmium palmitate, calcium manganese or nickel behenate, lead or cobalt oleate or lead or zinc erucate

used.

Claims (6)

1 2 To put such a stencil sheet into a stencil Claims: to convert, one generally covers it with an original bearing the desired image and Heat-sensitive stencil sheet made of one exposes the latter to infrared radiation, as a result of which porous, thin carrier sheet and one directly 5 the stencil sheet is perforated. Here has ink-impermeable exposure amount applied to it, d. H. the exposure time, one Film layer, characterized, noticeable influence on the clarity of the on the that the film layer essentially obtained from a stencil perforation image, thermoplastic resin together with plasticizers and too little infrared radiation creates a a visibly reactive, heat sensitive io defective perforation, and the one with the Component exists, the transfers produced in the temperature range nenen stencil are blurred, from 80 to 180 "C is able to change its color. And if the infrared radiation is too strong, the generated 2. stencil sheet according to claim 1, characterized by perforation too strong compared to the original image, indicates that the thermoplastic resin is made of and blurred transfers are again obtained. at Polyvinyl acetate, polystyrene, cellulose butyrate, 15 the known, in the manner described above Celkiloseace.at propionate, ethyl acetate, vinyl-made stencil sheets, it was extremely up to now Chloride-Vinyliieetatcopolynier, rosin-male- difficult to judge with the naked eye whether acid-denatured resin mixture, coumarone /, the perfo acrylic produced by infrared radiation !! "/, Methacrylic resin, cellulose acetate or ratio image properly formed, d. H. whether the right one Is made up of methyl cellulose. 20 degree of exposure had been applied. In- 3. SehablonenblaM according to claim 1 or 2, as a result one could determine the correct exposure characterized in that the film layer - determine to size only by trial and error, d. H. the 1 m - sheet area related - in terms of resin solid, capture approximately correct exposure by measuring the Plasticizer and heat-sensitive compo- stencil sheet converted to stencil, with nep.te with a total weight of 3 to 50 g and - made transfers on 25 of these and these with the original I part by weight of resin solids - 0.1 each compared. up to 1.0 part by weight of plasticizer and heat-sensitive To improve the recognizability of the perfo- Contains linuliche component. ration degree of a stencil sheet and consequently 4. Stencil sheet according to one of the preceding for a more precise setting of the exposure time the claims, characterized in that the 30 already proposed (German Auslegeschrift heat-sensitive component consists of substances 1 961 974), in the case of a heat-sensitive stencil, as is usually used for heat-sensitive sheets, which consist of a thin, porous carrier paper borrowed copy materials are used. and a film that is a thermoplastic 5. Stencil sheet according to one of the preceding contains synthetic resin as the main component and on which the claims, characterized in that " ¹ " is attached to the 35 a carrier paper side with the help of a binder film layer in addition a metal salt of a fat, a visibly reacting preparation in the acid contains 10 to 22 carbon atoms. To accommodate binder layer. 6. stencil sheet according to claim 5, characterized in contrast, should by the invention marked, da3 the metal salt - to 1 Ge recognizability of the degree of perforation heat-sensitive part Resin solid based - modified and / or used in an amount of 40 sensitive stencil sheets 0.1 to 1.0 part by weight is present. and determining the correct exposure be relieved. The subject of the invention is thus a heat-sensitive Sensitive stencil sheet made from a porous, thin one 45 carrier sheet and an ink-impermeable Fümschiuit applied directly to it, in which The invention relates to a heat-sensitive film layer either just a visibly reacting, liches stencil sheet made from a porous, thin heat-sensitive preparation or such a pre-carrier paper and on it, non-transparent and additionally a heat-fusible reliable film, in particular of the type that is used in 50 contains bond, the molten part of which can be converted into a substance that is transparent to its conversion to a transfer printing stencil.
During the perforation process colored and, to put it another way, the naked eye of the invention is able to deliver high-contrast images. appropriate Schabinnenblatt in such a way that one The known heat-sensitive stencil-porous thin paper with a resin solution in the sheets are usually produced in such a way that a mixture of the above-mentioned thermostats is produced by removing up to 4 g / m 2 on a porous, thin, for example plastic, synthetic resin and plasticizer ² heavy backing paper made mainly of neither one visibly reacting, heat-sensitive either natural fibers from Mitsumata, paper-sensitive compound alone or together with mulberry tree, Manila hemp, etc. Acrylic 60, thereby forming a film thereon with an ink resin, polyamide and the like by forming an impermeable film. These invention paper with the solution of a thermoplastic according to usable, visibly reacting, heat-resin, such as polyvinylacetate.Polystyrene, cellulose acetate-sensitive compounds include - as later butyrate, cellulose acetate propionate, ethyl acetate, vinyl will be explained in more detail - those compounds in vinyl chloride-vinyl acetate 65 or compositions that are usually used for the substances listed below in Table I in the production of the so-called heat-sensitive, which also uses a plasticizer, such as those copying materials that contain mineral oil or hydrogenated abietate ester. Copying infrared treatment alone. There