DE1546736C3 - Pressure sensitive transmission element and process for its manufacture - Google Patents

Description

The invention relates to new pressure-sensitive transfer elements for duplication purposes, z. B. for hectographic reproduction and magnetic scanning and the like., As well as a method for Manufacture of such transmission elements. In particular, the invention relates to transmission elements, which wear fragile layers that are completely under the action of an image-forming agent Pressure are transferable and which are built up on resinous binders, which by means of volatile organic solvents and can be applied at normal room temperatures.

Until a few years ago, practically all carbon papers and ribbons on wax binders

3 4

and after the hot melt elasticity or resistance to cracking were produced, nowadays a lot of time flaking or powdering will affect and and effort on the use of synthetic which in addition in the manufacture of plastics and resins in place of the usual support arches, which Wear such layers, directed pro-waxes. Due to this development 5 problems arise in the work process,
A number of new products resulted, some of which are said to be similar to one another for use and some to show very significant differences in the areas of reproduction and hectography. as well as in the magnetic field and so on

The transfer layers can be made of plastic or that they can be constructed without the use of auxiliary materials Resin-like substances can be used in two different io coatings for better transfer to a copy group subdivide. The first represents the so-called sheet, although such auxiliary coatings are suitable for porous squeeze-out layer, as used in the German special purposes if necessary see Auslegeschrift 1 095 860 is described, and can be.

the resin in non-fragile or non-transferable- The invention relates to pressure-sensitive overbars Form is present and only as a sponge-like 15 support elements, consisting of a flexible Ink dispenser for oily or pasty printing underlays with a fragile transfer layer color mass acts, which is not compatible with the resin, which in the form of an image under the effect are bearable. The second group is e.g. B. is transferable in a reproduction print and is dadeutschen Patent specification 1 147 244 and the German characterized in that the layer is a binder Auslegeschrift 1205119 described, which contains 20, which is completely free of waxes and wax binders made of plastic or a similar resinous substance and of at least two sub-substances is in fragile form and very similar to various synthetic thermoplastic film such as a common wax binder works. forming substances consists at least partially

The present invention relates to a fragile mutually incompatible and those in such

Transfer layer of the latter type and the purpose of 25 parts are present that 10 to 50 weight

thus, the tendency of a plastic or resinous percentage of the total film-forming substance content with

Material for the formation of a continuous, not the remaining part of the film-forming substance content

to overcome fragile film. For those who have not been tolerated so far.

known resinous transfer layers. The invention is primarily concerned with

with varying degrees of success this property on 30 manufacture of carbon papers and tapes that

tried different ways to overcome. According to additives such as pigments and dyes that contain

All previously known methods will be used for duplication, hectography and magnetic

Resinous binders in a fragile form make it suitable for scanning.

by adding waxes, oils or similar such additives, as well as those for the manufacture, by having the self-binding properties of the 35 built-in reduction of the cost of the coating Resin can be overcome, or by opacification fillers, the effect, the fragility of the processes in which an incompatible volatile resinous transfer coatings increase. However Agent is added so that voids or micro- such additives can be omitted, though pores remain in the resinous layer, whereby a pure resin transfer layer is desired, the continuity of which is interrupted and they turn into a 40 but in these cases the fragile ones are expediently the most fragile State comes, transferred. So also the possibility of the transmission layer in any usual z. In an older, not prior art manner, e.g. by means of a thin wax coating Proposal belonging to the one for the writing and / or by using the transfer layer Layer as a binder plastic in company together with a receiving layer to which it has a strong affinity with wax or wax-like substances.

that the waxes or wax-like It is an important aspect of the invention,

Substances quantitatively the plastic content of the binding that the present transfer layers one

means by no more than 10%. relatively high proportion of resinous binder,

Even if some of these known transfers, related to the other constituents, contain and are bent more dense, more uniform and smear-resistant as a result for certain specific uses, the uses in digere image areas result than is generally the case with use due to the nature of the additives which is possible from known transfer layers, fragile and / or greasy properties which must contain large amounts of additives, finished transfer layer or which is insufficient - so that the binder becomes fragile,
55 The addition of large amounts of wax additives limits what makes it necessary, they in combination give rise to processing problems, since wax is difficult to dissolve in or- gan with a special receiving layer on the copying solvent and bent or in combination with a solvent special over- must be heated slightly in order to draw in the dissolution or to transfer a special pad to the over- head. This heat is to be used throughout the contract arch or tape. 60 work difficult to keep constant, and it yields

The main aim of the invention is to thereby produce also an evaporation of the organic a fragile transfer layer of solvent and a lack of control over viscous build-up the basis of binders made of plastic or the strength of the coating solution and a lack of uniform resin-like substances, without any substantial admissibility of the coating. Such coatings are also would give large amounts of waxes, oils or turbidity 65 relatively soft and dirty when touched and It is necessary to use exercise agents that give the natural relatively soft, greasy reproductions advantageous properties of resins as such, due to the presence of large amounts of wax, namely their clarity, smear resistance and The addition of large amounts of oil leads to an

number of difficulties. If the oil is completely incompatible with the binder, it tends to separate out and droplet formation oozing out of the binder upon standing or under pressure. Thus owns the binder has a tendency to remain on the substrate while the oil is transferred under pressure or the oil seeps into the substrate as it ages, so that the layer is not transferable. If If the oil is compatible with the resin binder, it softens the binder so that the layer on contact dirty and results in soft, greasy reproductions.

The resinous transfer layers according to the invention are required to achieve fragility no such additives, which as a result are completely omitted or, if applicable, in such Portions can be used in which the previous problems with regard to lubrication, leakage or loss of fragility, peeling or the like does not occur.

The most important components of the transfer layers according to the invention are the film-forming binders. These are all thermoplastic binders, some of which are commonly called plastics and others are called resins. Suitable film-forming binders include Vinyl resins such as polystyrene, styrene copolymers with butadiene and the like, polyvinyl acetate, acrylic acid and Methacrylic acid and esters and copolymers thereof, copolymers of methyl vinyl ether and Maleic anhydride, polybutenes and the like; Cellulosic plastics including ethyl cellulose and ethyl hydroxyethyl cellulose, Alkyd resins and alkyd resins modified with colophony, polyterpene resins, arylsulfonamide-formaldehyde resins, Urea-formaldehyde resins, and others. Although some of the thermoplastic film-forming binders listed above are partially or completely compatible with one another, it is for the person skilled in the art on the basis of the present Easily teach you to choose combinations of incompatible binders or the limits of compatibility to determine of partially compatible such binder combinations. The following The table serves to explain various combinations of suitable binder combinations in preferred ones Circumstances; however, other combinations are readily apparent to those skilled in the art and relationships.

Tabel

Film-forming binders relationship 1 3.5 1: 1 Ethyl cellulose and polystyrene from 2: 1 until 12 1 Ethyl cellulose and acrylic ester resin .... 1: 1 1 Polystyrene and acrylic ester resin of 2:] up to 1: 1 1: 1 Polystyrene and ethyl hydroxyethyl cellulose .. 1: 1 1: 1 Polystyrene and a polyterpene resin ... 1: 1 Chlorinated rubber polymer and 1: 1 a polyterpene resin 1: 1 Acrylic ester resin and a polyterpene resin 1: 1 Acrylic ester resin and a copolymer sat from styrene homologists 1: 1 alkyd derived from rosin resin and urea formaldehyde resin 1: 1 Polyvinyl acetate resin and a mixture polymer from methyl vinyl ether and maleic anhydride 1 Polyvinyl acetate resin and toluene Sulfonamide resin 1 Ethyl cellulose and cellulose ether .... 1 Polystyrene and acrylic ester resin and Polyterpene resin 1 Polystyrene and acrylic ester resin and Ethyl cellulose 1 Polystyrene and polybutene isomer resin and ethyl cellulose 1 Polystyrene and ethyl hydroxyethyl cellulose and chlorinated polyphenylene resin

The transfer elements according to the invention are produced by solvent coating processes, wherein the transfer mass is dissolved in one or more volatile organic solvents, on a flexible surface, such as B. paper or plastic film, at normal room temperature

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drawn up and the hardening and solidification by Example 5

Allowing the solvent to evaporate.

It is a critical feature of the process. Components by weight

measured the invention that the incompatible film polystyrene 0.73

forming binder in the used 5 ethyl cellulose 0.73

Solvents must be dissolved together, so that. Polybutene isomer resin 0.40

them in the same solution and not as separate lanolin 0.61

Layers are in place. In most cases, Milori blue 1.10

a single solvent can be found that both clay 12.33

dissolves film-forming substances. In other cases it is necessary toluene 43.20

agile, a combination of miscible solution methyl isobutyl ketone 11.00

funds to use, each of which is one of the

film-forming substances dissolve, so that a single example 6

Solution results. ■. ■

Possible additives, such as pigments, fillers, 15 components by weight

Dyes, oils and other substances that are in the over- Polystyrene 8.7

If the load-bearing layer is to be installed, ethylhydroxyethylcellulose 2.5

preferably with a small amount of the solution-chlorinated polyphenyl resin 2.5

by means of rapeseed oil pre-refined to form a slurry 9.8

mixes, which is then added to the resin solution. 20 Sulphonated vegetable oil 0.5

In the following examples, some weights are bluewood black 10.0

listed according to the invention, which various indulin oleate 4.0

Contain additives that set the masses for the intended- Ethyl acetate 62.0

make it suitable for the intended use. These

Masses are for explanatory purposes only and may 25 As already stated above, the should not be viewed as a limitation. In every essential aspect of the invention on the solid-case are the special masses for mounting on position that a fragile transfer layer a flexible base, such as paper or plastic, made from two thermoplastic film-forming binders Film, can be formed by conventional solvent coating processes provided that it is in suitable at normal room temperature, and the proportions are present in such proportions that at least The coating is set by evaporating the 10 percent by weight of each resin with the rest volatile organic solvent .. · Part of the resin content is incompatible. Thus can

in cases where the two resins used

Example 1 are completely incompatible with each other, the second resin

35 in an amount corresponding to 10 percent by weight to

Components by weight _to 90 percent by weight of the total resin content before polystyrene 1.2. In the case of partial tolerance,

Ethylcellulose 1.2, for example, a 50 ° / ₀ aqueous compatibility, must

Magnetic iron oxide 18.1 the second resin in an amount corresponding to 20 Ge

Toluene 79.5 to 40 percent by weight up to 80 percent by weight of the total resin content, since both at 20 ° / ₀ and at 80% in each case 10% of the resin present in the smaller amount of Example 2 is incompatible.

. It's quite difficult to push the boundaries of the Ingredients parts by weight 45 percent resin content, which is in the

Polystyrene 1.2 transfer layer may be present. This leaves

Ethyl cellulose 1,2 itself in cases where it is completely resinous

Tone 16.8 transfer layer, free from coloring matter and

Milori Blue 1.5 other additives that are desired achieve, however

Toluene 79.350 generally becomes an undercoat, topcoat

and / or a receiving layer applied to reduce the fragility of the resinous transfer layer

B eis ρ ie 1 3 _Z u promote. Suitable coatings and / or top coatings for this purpose are described in USA. Patent Ingredients Parts by Weight ₅₅ writing 2,912,344. Suitable recording

Polyterpene resin 1.0 coatings with an affinity for the present resin

Acrylic ester resin 0.9 type transfer coatings, consist of thin

Hectographic blackness 13.7 resinous coatings that are sticky on adherent

Toluene 9 84.4 materials such as butadiene styrene polymers, poly

60 isobutenes, acrylic resins or the like. Are built up, which small amounts of suitable fillers, such as clay, for

Example 4 Reduction of the sticky feel of the coatings

contain, and yet their capacity to absorb constituents parts by weight for the resinous transfer layers.

Polystyrene 2.4 65 hold.

Acrylic ester resin 1,2 Although the present transfer layers

Magnetic iron oxide 20.0 consist solely of the resinous binders

Toluene 76.4 can, but these are preferably used for binding

large amounts of dyes, for example hectographic Dyes, pigments, including magnetic pigments, or other functional additives. It has been found that the binder is present in an amount of at least about 10 percent by weight of the must be present throughout the dry transfer layer.

Preferably, the present transfer layers are free from large amounts of additives that do not consist of temperature-stable solids, for example oils, fats, waxes or the like., since such additives have a tendency to migrate or sweat out of the layer or their Change character when the layer is exposed to heat or cold, reducing its fragility the transfer layer is affected. Although in some cases such additives can be advantageous they should never be present in such quantities as to match the quantity of the dry Existing resin binder in the transfer layer.

The greatest advantage of the invention is probably in the avoidance of the hitherto used for the production of fragile resinous layers necessary additives. The invention enables z. B., resinous transfer layers Manufacture that only has about 10 percent by weight binding material and up to 90 percent by weight contain hectographic dye or magnetic pigment. By using such transfer layers it becomes possible e.g. B. to produce hectographic stencil sheets that produce far more sharp and clear hectographic spirit copies than usual hectographic ones Transfer sheets are generally only about 25 to 50 percent by weight of a hectographic Contain dye. In accordance with this aspect of the invention, the present hectographic transfer sheets between about 10 and 20 percent by weight resinous Binder, about 70 to 90 weight percent undissolved particulate dye contained in is insoluble in the volatile organic solvent and, optionally, up to 20 percent by weight other additives, e.g. B. oil, wax or filler. These proportions were found to be equally satisfactory in the case of magnetic pigments, instead of hectographic dyes during manufacture magnetic sheets or ribbons.

Although in many cases it is preferred that the presence of unduly large amounts of fillers, like talc and clay, which show a tendency to make the transfer coatings somewhat brittle and somewhat To make it dirty when attacked, such fillers can be used in varying amounts if desired can be added to increase the fragility of the coatings and / or the cost thereof without practically disturbing the clarity and stability of the present transfer layers will. This is generally desirable in the field of reproduction, where a number of transmission and recording sheets can be superimposed and labeled at the same time to form a large one Number, for example eight or more, to give individual copies.

Claims (14)

Patent claims: 1. Pressure-sensitive transmission element, consisting of a flexible base that has a fragile transfer layer that bears in the form of an image under the action of a Reproduction print is transferable, characterized in that the layer is a binder contains, which is completely free of waxes and wax-like substances and of at least two different synthetic thermoplastic film-forming substances consists of at least are partially incompatible with one another and which are present in such proportions that 10 to 50 percent by weight of the total film-forming substance content with the remaining portion the film-forming substance content are incompatible. 2. Pressure-sensitive transmission element according to claim 1, characterized in that the Layer 10 to 100 percent by weight of at least two different synthetic thermoplastic contains film-forming substances. 3. Pressure-sensitive transmission element according to claim 1 or 2, characterized in that that the layer is completely incompatible synthetic thermoplastic film-forming Contains substances made up of 10 to 90 percent by weight of a first synthetic thermoplastic film-forming Substance and from 90 to 10% of at least one other synthetic film-forming substance exist. 4. Pressure-sensitive transmission element according to claim 3, characterized in that the first film-forming fabric made of cellulosic material and the second film-forming fabric made of a vinyl resin consists. 5. Pressure-sensitive transmission element according to claim 3, characterized in that the first film-forming material made of ethyl cellulose and the second film-forming material made of polystyrene consists. 6. Pressure-sensitive transmission element according to one of the preceding claims, characterized characterized in that the layer contains up to 90 percent by weight of a coloring material contains. 7. Pressure-sensitive transmission element according to claim 6, characterized in that the coloring material consists of an undissolved hectographic dye. 8. Pressure-sensitive transmission element according to claim 6, characterized in that the coloring material consists of a magnetic pigment. 9. A method for making pressure sensitive transfer elements according to claims 1 to 8, characterized in that one is in a volatile organic solvent a mass that contains a binder which is completely free of wax and wax-like substances Substances and which of at least two different synthetic thermoplastic film-forming There are substances that are at least partially incompatible with one another in the dry state are and are dissolved together in the organic solvent, dissolves, the film-forming Substances are present in such proportions that 10 to 50 percent by weight of the total film-forming Substance content with the remaining proportion of the film-forming substance content in the dry state are incompatible, place the solution in the volatile organic solvent on a flexible surface and the volatile organic solvent to form the fragile transfer layer evaporates. 10. The method according to claim 9, characterized in that one in the volatile organic Solvent 10 to 100 percent by weight of at least two different synthetic ones thermoplastic film-forming materials that are at least partially interconnected in a dry state are incompatible and are dissolved together in the organic solvent, dissolves. 11. The method according to claim 9 or 10, characterized in that in the volatile organic Solvent 10 to 90 percent by weight of a first synthetic thermoplastic film-forming Fabric and 90 to 10 weight percent of at least one other thermoplastic film-forming material Substance that is practically completely incompatible with the first substance can be dissolved. 12. A method for making pressure sensitive transfer elements according to claims 9 to 11 with a flexible base carrying a collapsible transfer layer, the practically in the form of a reproduction under the effect of a picture print completely is transferable, characterized in that the solution of at least 10 percent by weight of at least two different synthetic thermoplastic film-forming substances, which are at least partially incompatible with one another in the dry state in a volatile organic solvents add up to 90 percent by weight of a coloring material, applies this solution to a flexible surface and the volatile organic solvent evaporated to form the fragile transfer layer. 13. The method according to claim 12, characterized in that a coloring material is used undissolved hectographic dye is used, which is in the volatile organic Solvent is insoluble. 14. The method according to claim 12, characterized in that a coloring material is used magnetic pigment is used.