DE1546736B2 - Pressure-sensitive transmission element and method 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 in two different ίο coatings for better transfer to a copy groups 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 1147 244 and the German characterized in that the layer is a binder Auslegeschrift 1 205 119 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. After containing additives like pigments and dyes that

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 broken and it turns into a 40 but in these cases the fragile ones are expediently State comes, transferred. So also the possibility of the transmission layer in any usual e.g. in an older, not state-of-the-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 touches it 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
1
1
1: 1
1: 1
1: 1
1: 1 Ethyl cellulose and polystyrene
Ethyl cellulose and acrylic ester resin ....
Polystyrene and acrylic ester resin
Polystyrene and ethyl hydroxyethyl
cellulose from 2: 1
until 12
1: 1
from 2: 1
up to 1: 1
1: 1
1: 1
1: 1
1: 1
1: 1
1: 1 Polystyrene and a polyterpene resin ...
Chlorinated rubber polymer and
a polyterpene resin
Acrylic ester resin and a polyterpene resin
Acrylic ester resin and a copolymer
sat from styrene homologists
alkyd derived from rosin
resin and urea formaldehyde
resin 1
1
1
1
1
1
3.5 Polyvinyl acetate resin and a mixture
polymer from methyl vinyl ether
and maleic anhydride
Polyvinyl acetate resin and toluene
Sulfonamide resin
Ethyl cellulose and cellulose ether
Polystyrene and acrylic ester resin and
Polyterpene resin
Polystyrene and acrylic ester resin and
Ethyl cellulose
Polystyrene and polybutene isomer resin
and ethyl cellulose
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

drawn up and left to harden and solidify by evaporation of the solvent.

It is a critical feature of the process according to the invention that the incompatible film-forming Binder must be dissolved together in the solvent or solvents used, so that they are in the same solution and not as separate layers. In most cases a single solvent can be found that dissolves both film-forming substances. In other cases it is necessary to use a combination of miscible solvents, each of which is one of the dissolves film-forming substances, so that there is a single solution.

Any additives, such as pigments, fillers, dyes, oils and other substances, that are in the transfer layer to be incorporated are preferably with a small amount of the solvent premixed to form a slurry which is then added to the resin solution.

In the following examples some compositions according to the invention are listed, which are different Contain additives that make the masses suitable for the intended use. These Masses are for illustrative purposes only and should not be viewed as limiting. In each Case are the special masses for pulling on a flexible base, such as paper or plastic film, suitable for conventional solvent coating processes at normal room temperature, and the solidification the coating is carried out by evaporation of the volatile organic solvent.

Example 5 example 1

35.

Components parts by weight

Polystyrene 1.2

Ethyl cellulose 1,2

Magnetic iron oxide 18.1

Toluene 79.5

B e i s ρ i e 1 2

Components part by weight

Polystyrene 1.2

Ethyl cellulose 1,2

Tone 16.8

Milori blue 1.5

Toluene 79.3

Example 3

Components parts by weight

Polyterpene resin 1.0

Acrylic ester resin 0.9

Hectographic blackness 13.7

Toluene 9 x 84.4

60

B e i s ρ i e 1 4

Components parts by weight

Polystyrene 2.4

Acrylic ester resin 1,2

Magnetic Fjsen Oxide 20.0

Toluene 76.4

Components parts by weight

Polystyrene 0.73

Ethyl cellulose 0.73

Polybutene isomer resin 0.40

Lanolin 0.61

Milori blue 1.10

Tone 12.33

Toluene 43.20

. Methyl isobutyl ketone 11.00

Example 6

Components parts by weight

Polystyrene 8.7

Ethyl hydroxyethyl cellulose 2.5

chlorinated polyphenylene resin 2.5

Refined rapeseed oil 9.8

Sulphonated vegetable oil 0.5

Bluewood black 10.0

Indulin oleate 4.0

Ethyl acetate 62.0

As already stated above, the essential aspect of the invention is based on the finding that a frangible transfer layer of two thermoplastic film-forming binders may be formed, provided that they are present in proportions such that at least 10 percent by weight of each resin is incompatible with the remainder of the resin content. Thus can in cases where the two resins used are completely incompatible with one another, the second resin present in an amount corresponding to 10 percent by weight up to 90 percent by weight of the total resin content be. In the case of partial compatibility, for example 50% compatibility, must the second resin in an amount corresponding to 20 percent by weight up to 80 percent by weight of the total resin content be present, since both at 20% and at 80% in each case 10% of that in a smaller amount the existing resin are incompatible.

It is quite difficult to set limits on the percentage of resin that can be used in the Transmission layer may be present. This can be done in cases where a completely resinous Transfer layer, free of coloring agents and other additives, is desired to achieve, however Generally, an undercoat, overcoat and / or receiving layer is applied to the Promote fragility of the resinous transfer layer. Suitable undercoats and / or topcoats for this purpose are described in U.S. Patent No. 2,912,344. Suitable receiving covers having an affinity for the present resinous transfer coatings are thin resinous coatings that are applied to adhesive sticky materials such as butadiene styrene polymers, polyisobutenes, Acrylic resins or the like. Are built up, the small amounts of suitable fillers, such as clay, for Contain a reduction in the sticky feel of the coatings, while at the same time their absorption capacity retained for the resinous transfer layers.

Although the present transfer layers consist only of the resinous binders can, these are preferably used for binding

309 541/149

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larger amounts of colorants, for example hecto- copies, result than it would with usual hectographic graphic dyes, pigments, including magne transfer sheets is possible, in general table pigments, or other functional additives. only about 25 to 50 percent by weight of a hectare-es it was found that the binder contained a graphic dye. According to this Amounts of at least about 10 percent by weight of the embodiment of the invention include the entire dry transfer layer present between lying hectographic transfer sheets got to. see about 10 and 20 percent by weight resinous

Preferably, the present transfer binders, about 70 to 90 percent by weight uncoated, are free from large amounts of additives that dissolve, in particulate form, which do not consist of temperature-stable solids, are insoluble in volatile organic solvents, for example oils, fats, waxes Od. The like., Is and, optionally, up to 20 percent by weight since such additives have a tendency to make other additives such. B. oil, wax or filler. This layer migrates or exudes, or the proportions thereof have been found to change equally satisfactorily when the layer is exposed to heat or instead of cold in the case of magnetic pigments, which affects the fragility of the hectographic dyes in the manufacture of the transfer layer . Even if magnetic sheets or ribbons,
Such additives may be advantageous in some cases. Although in many cases it is preferred, they should never be present in amounts such as excessively large amounts of fillers, that they exceed the amount of the dry matter, such as talc and clay, too Avoid the tendency of the resin binder 20 present to cause the transfer layer to become somewhat brittle and exceed the transfer coats. to make dirty when attacking, the-

The greatest advantage of the invention is believed to be like fillers in varying amounts the avoidance of the coatings previously necessary for the production of, if desired, in order to increase the fragile fragile resinous layers and / or the cost of the coatings. The invention enables z. B. to lower resinous over- 25 same, without practically the clarity and Produce support layers that have only about 10% stability of the present transfer layers by weight Binding material and up to 90 weight is disrupted. This is common in the percentage area of hectographic dye or magnetism is desirable where a number of over-the-counter tables Contain pigment. Due to the use of support and recording sheets superimposed Such transfer layers will make it possible to write 30 and at the same time to a large one z. B. to produce hectographic stencil sheets, the number, for example eight or more, individual to produce far more sharp and clear hectographic spirit 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 pressure is transferable, thereby characterized in that the layer contains a binder which is completely free of waxes and wax-like materials and made of at least two different synthetic thermoplastic materials film-forming substances that are at least partially incompatible with one another and which are present in proportions such that 10 to 50 percent by weight of the total film-forming Substance content are incompatible with the remaining part of the film-forming substance content. 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 transfer element according to one of the preceding claims, characterized in that the layer up to Contains 90 percent by weight of a coloring material. 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 part 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 of 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 substance and 90 to 10 weight percent of at least one other thermoplastic film- _{-forming substance, which practically completely with the first material incompatible, be resolved. 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 _v hektografischer undissolved dye is used as a coloring material which is insoluble in the volatile organic solvent. 14. The method according to claim 12, characterized in that a coloring material is used magnetic pigment is used.