JPH026183A - Thermal transfer sheet - Google Patents

Abstract

PURPOSE: To form a transparent film suitable used for overhead transparent projection by forming a coat including a transfer medium consisting of haloganted hydrocarbon containing organic dye. CONSTITUTION: A coat including a transfer medium consisting of halogenated hydrocarbon containing organic dye is formed on a carrier. The coat has preferably a thickness of 1-10 μ, and preferably a thickness of 2-30 wt.% dye. The transfer medium contains at least 80 wt.% halogenated hydrocarbon preferable at least 90 wt.%, in particular, 95-100 wt.%. The halogenated hydrocarbon has a softening point of 50 deg.C at least and preferably of 50-100 deg.C. The halogenated hydrocarbon is chlorinated paraffin preferably containing a 65-75 wt.% chlorine component, and this is obtained by chlorinated paraffin or a paraffin mixture having 18-35 carbon atoms.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF APPLICATION This invention relates to thermal transfer materials useful in thermal transfer processes.

In the case of conventional thermal transfer methods, transfer sheets or films made of paper or glass material have on one side a coating consisting of a pigment and a wax, such as carnauba wax, paraffin wax, montan wax or beeswax. When a thermal head activated by an input color signal corresponding to the coloring of the colored original generates heat on the other side of the transfer sheet or film, the wax coating melts and re-images the colored original. Transferred to a material or duplication sheet.

This type of method is used, for example, in the UK *r't' No. 2069160.
Described in the issue of Rete Inle.

In JP-A No. 58-162678, since some defects of waxes commonly used, especially some paraffin waxes that cause progressive deterioration in recording properties, appear,
It has been proposed to use pigments with chlorinated paraffin waxes that are easily miscible with other waxes commonly used in wax transfer printing. In particular, for carbon black, chlorinated paraffin of Xt (m, p, 50-56°G)
and an ink composition containing carnauba wax tubes.

Unfortunately, pigments, when used with the waxes described in the prior art for this purpose, give coatings with insufficient transparency for some applications; however, some dyes, rather pigments, When used with some halogenated hydrocarbons, the amorphous nature of the halogenated hydrocarbon thermal transfer media allows for overhead transparent projection.
It has been found that a transparent film suitable for use in ns-parency projects can be obtained.

SUMMARY OF THE INVENTION Accordingly, the present invention provides a thermal transfer sheet taken from a support having thereon a coating comprising a transferable medium comprising a halogenated hydrocarbon containing an organic dye.

The support used when producing the transfer sheet according to the invention is suitably a gelastec film or paper having a thickness of 6 to 25 .mu.m.

Specific examples of such supports include polyethylene terephthalate film, polyethylene film, polyethylene film, polystyrene film, glassine paper,
Synthetic paper and laminated paper.

The coating preferably has a thickness t of 1 to 10 microns and preferably contains a total amount of 2 to 30 Jk of dye.

The transfer medium is a halogenated hydrocarbon of at least 803k
n, more preferably at least 90, especially 95
Contains ~100mk chi.

The residual portion of the transferable medium may consist of waxes such as carnauba wax, paraffin wax and emollients such as stearic acid, chlorostearic acid and oleic acid.

The halogenated hydrocarbon preferably has a softening point 'I: of at least 50°C, more preferably from 50 to 100°C.

The halogenated hydrocarbon preferably has a chlorine content of 65 to 7511
-r chlorinated paraffins, which are obtained by chlorination on paraffins or paraffin mixtures having from 18 to 65 carbon atoms.

As mentioned above, chlorinated paraffins may be single paraffins or
? , may be based on a paraffin mixture. However, although single chlorinated paraffins can be produced and are known, common commercially available fabrics consist of mixtures obtained by chlorinating mixed paraffins having a range of carbon chain lengths. . For example,
The so-called C18-26-halafine fraction, which may be used to produce the chlorinated paraffins used, may contain small amounts of paraffins with chain lengths outside the abovementioned range.

Chlorinated paraffin can be produced by chlorinating excessively supplied paraffin to a desired chlorine content using known methods. Any known method for producing chlorinated paraffin may be used, and these generally consist of passing chlorine gas through gold liquid paraffin at temperatures above about 8 ff'C.

The chlorinated paraffin''1-fc coating present in the transfer sheet according to the present invention may contain any additives normally incorporated into the chlorinated paraffin composition, namely stabilizers and modifiers. The chlorinated paraffins obtained usually contain a stabilizer or a mixture of stabilizers to impart photostability, vertical stability and storage stability to the composition. Epoxidized epoxides such as soybean oil.

The dyes present in the transfer sheet of the present invention are preferably soluble in halogenated hydrocarbons. This solubility distinguishes dye systems from pigments which are generally largely insoluble in the medium in which they are used.

Convenient dyes generally do not have water solubilizing groups or ionic groups such as disulfonate groups. Examples of suitable dyes include dyes classified by the Color Index as disperse dyes or solvent dyes. If the preferred dye has excessive solubility, chemical classification is not straightforward except to take into account that some colors may be associated with specific chromophores. Most dyes are based on azo, anthraquinone, triarylmethane or pennzodifuranones.

If desired, pigments may be included in the transferable medium together with dyes in order to achieve the desired combination of high lightfastness, high transparency and good visual yields. Work. Suitable pigments are inorganic, but preferred pigments are organic.

Examples of suitable organic pigments are azo, diazo, thioindigo,
Pigments of the anthraquinone, anthanthrone, isobenzonthrone or triphendioxazine series, vat dye pigments, phthalocyanine pigments (e.g. steel phthalocyanine, its nuclear halogenated derivatives and copper tetraphenyl and octaphenyl phthalocyanine), quinacridone pigments, dispersions, bases and mordant dye lakes and especially alpha and beta forms of copper 7j10 cyanine and carbon black, which are advantageously classified as organic pigments due to their dispersion properties.

Such pigments are classified by, for example, Co1our Index (
The second edition, 1956, is published in the sixth edition, 1971, under the heading "Pigments" in the second volume, and in subsequent authorized revisions.

Suitable inorganic pigments include transparent iron oxides.

The pigment is preferably formulated as a dispersion by grinding in a suitable organic solvent with a dispersant and/or a fluidizing agent, and mixing the dispersed metal halogenated hydrocarbon and dye. The use of a suitable dispersant has been found to be M* in obtaining a good transfer sheet since the chlorinated paraffin has minimal dispersibility.

If all pigments are used, any suitable dispersant known in the pigment art may be used, but preferred dispersants are those made from hydroxy fatty acids, namely hydroxystearic acid, ricinoleic acid and caprolactone, or mixtures thereof. Polymeric dispersants with derived bath-solvating chains. Particularly preferred dispersants are those in which alkylamines, particularly polyalkyleneimines, are also incorporated; such dispersants are described in British Patent No. 1.373,660, European Patent Application No. 158,406 and European Patent Application No. 158,406; 208
, No. 041.

Suitable superplasticizers are described in British Patent Nos. 1,508,576 and 2,108,143. English 8
! The superplasticizer of 1% License No. 1.508.576 is a direct ammonium salt of a colored acid, in which at least 6 chains attached to the Nl1A atoms of the substituted ammonium ion contain 19 to 60 carbon atoms. exists. In this loincloth preferred fluidizing agent for use with phthalocyanine pigments, the colored acid contains an average of 1 to 2 sulfonic acid groups per
Steel 7 talocyanine sulfonic acid. Colored acids themselves, rather than ammonium salts, may also be used as fluidizing agents.

The fluidizing agent of British Patent No. 2,108,143 has two monovalent end groups on the azo group (one end group does not carry acid substituents and other ionic substituents; the end group of has a substituted single ammonium base)
It is a water-insoluble diazotized adduct consisting of a central divalent group without any substituents or ionic substituents. Such superplasticizers are useful in increasing the fluidity of pigment and wax dispersions in organic liquids so that the dispersions can advantageously be milled and applied to a support.

Although suitable dye/pigment compositions may contain up to 1% of pigment 95, such as 10 to 90 Jkts, preferred compositions contain pigment 40 to 60 Jkts.

The coating a may be applied to the support as a melt, but is preferably applied as a solution or dispersion in an organic solvent such as tetrahydrofuran, toluene or methyl imbutyl ketone.

When used in heat transfer methods, a striking gray scale effect is observed, increasing uniformly with increasing thermal energy transferred from the support to the copy sheet and using a nine-color lid.

Next, the non-invention will be explained by examples, but the present invention is not limited to these examples.

Example 1 CI solvent blue
) 36 (2&i, solid chlorinated C1a = za-paraffin in tetrahydrofuran (981)
72%) (,1411)f) Temperature in solution L, 7'j.

This solution is applied to a 6 micron thick polyester film with a 43 bar (-0,001 inch wire bond) and dried to yield a clear colored film. When used in the thermal transfer printing process, the resulting batches had excellent clarity and brightness.

Example 2 Diazotized 5-amino-4-cyano-3-methylisothea dye formed by coupling with zoether-m-)luison (11), a mixture of chlorinated paraffins in tetrahydrofuran (991) 15&
) in a solution of The paraffin mixture was 90% chlorinated paraffin as described in Example 1 and chlorinated C14-1'F-
It consisted of 10% paraffin (40% C2).

The solution was passed through a 6 micron thick polyester film with the t-43 IC par and, when dried, yielded a transparent amber film with a lower melting point than the film described in Example 1.

This is suitable for use in transfer printing.

Example 6 Example 2) @all repeated, but the chlorinated 014-1°-paraffin was replaced with stearic acid of the same xil. This solution was applied to a thin polyester film with a bar to /i63 as in Example 1) , a transparent colored film was obtained upon drying. The same film has a lower melting point than the compound machine described in Example 1.
? and is suitable for transfer printing.

Example 4 CI Solvent Yell o -(5olvent Yell
ow) 93 (2II) t-1 A mixture of the friend-accumulated paraffins described in Example 2 (14I of tetrahydrofuran (
98.1 solution. This bath solution 'tA3% was applied to a polyester film having a thickness of 6 μm, and when dried, a transparent colored film was obtained.

This material is suitable for transfer printing.

Example 5 The procedure of Example 4 was repeated, but with chlorinated C14-1.

- Paraffin was replaced with chlorinated stearic acid (C1) 35%). This solution 1163 was applied to Birch thin polyester film and, when dried, yielded a transparent colored film suitable for transfer printing.

Example 6 Diazotized p-chloroaniline gold 6-dia2-6-hydroxy-4-methyl-1-octylpyrid-2-one (6
g) The dye produced by coupling with solid chlorinated cxs~26-paraffin (C
~72%) (13g) of tetrahydrofuran (97g)
It was dissolved in a solution inside. Above this solution, bar (
A clear colored film was obtained which was applied to a 6 micron thick polyester film (0,001 inch wire bond) and dried. When used in a thermographic printing process, the resulting image had excellent clarity and brightness.

Examples 7-62 The entire procedure described in Example 6 was repeated. However, the dye used in Example 6 was now replaced with the dye listed in the table below. The table also shows the dye stock used and the color of the resulting film.

The stearic acid used in Examples 6 and 7-32 may be replaced with palmitic acid or carnauba wax. Any of these materials may be suitably used at levels of 5 to 10 halogenated paraffins.

Example 36 Toluene (48,1, Pigment Blue
t Blup ) 15:3 (40 g), dispersant 8 (8,F) as described in European Patent Application No. 208,041 and European Patent Application No. 208
A mixture of Superplasticizer 1 (4 g) as described in CI41 was milled with 3 mx gas beads on a flatbed shaker for 24 hours. This dispersion was mixed with C18-2 having a chlorine content of 70%.
6 - A 10% solution of a chlorinated aliphatic hydrocarbon in toluene (
(103z5.F) gave a fine dispersion with a pigment/dye content of 4.4%. The dye used in this example was 1,4-bis-isozologylaminoanthraquinone.

Example 64 Toluene (51,!i'), l? G,,l tread (
Pigment Red) 48: 2 (35,
! i') and European Patent Application Publication No. 20804
A mixture of Dispersant 8 (141) described in No. 1 was ground by three people for 24 hours in a flatbed shaker together with Russ beads.

When this dispersion is diluted with a 10% solution of C18-26-chlorinated aliphatic hydrocarbons in toluene (also containing magneto dye 8.759 *') (894.3 g) with a chlorine content of 70%, the pigment/ A fine dispersion containing a dye content of 4.4 k was obtained.

The dye used in this example was N diazotized 5-amino-4-cyano-3-methylinthiazole.

The product obtained by coupling with N-diethyl-m-)luidine was 7, Example 35. Methyl isobutyl ketone (52,9), Pigment Yellow 12 (30 g), European Patent Application No. 208
[ ] Dispersion liquid 8 (12 g) and 5o described in No. 41
A mixture of LspERsE22000 (6y) was added to 3j
It was ground for 24 hours on a flatbed shaker with III glass beads. This dispersion was mixed with C18 to C18 having a chlorine content of 70q6.
26 10% solution of chlorinated aliphatic hydrocarbon in methyl isobutyl ketone (also contains 7.5 g of yellow dye) (752,
Dilution with 2 g) gave a fine dispersion with 4.4 weights of pigment/dye.

The dye used in this example was diazotized 4-chloroaniline'1
It was a product obtained by coupling with r1-n-butyl-5-cyano-4-methyl-6-hydroxypyrido-2-one.

Claims (1)

Claims: 1. A thermal transfer sheet consisting of a support having thereon a coating comprising a transfer medium consisting of a halogenated hydrocarbon containing an organic dye. 2. A sheet according to claim 1, wherein the coating contains 2 to 30% by weight of dye. 3. The sheet according to claim 1 or claim 2, wherein the transferable medium contains at least 80% by weight of halogenated hydrocarbon. 4. The sheet of claim 3, wherein the transferable medium contains at least 90% by weight of halogenated hydrocarbon. 5. The sheet according to claim 4, wherein the transferable medium contains 95 to 100% by weight of halogenated hydrocarbon. 6. A sheet according to any one of claims 1 to 5, wherein the halogenated hydrocarbon has a softening point of at least 50°C. 7. The sheet according to claim 6, wherein the halogenated hydrocarbon has a softening point in the range of 50 to 100C. 8. Claims 1 to 8, wherein the halogenated hydrocarbon is a chlorinated paraffin having a chlorine content of 65 to 72% by weight, obtained by chlorinating a paraffin or a paraffin mixture having 18 to 35 carbon atoms. Sheet listed in any one of the items up to 7. 9. Claim 1, wherein the dye is soluble in halogenated hydrocarbons.
The sheet according to any one of claims 1 to 9. 10. The sheet according to any one of claims 1 to 9, wherein the dye is one of azo, anthraquinone, triarylmethane, or penzdifuranone. 11. Claim 1, wherein the transferable medium contains a dye and a pigment.
The sheet according to any one of claims 1 to 10. 12. The sheet according to claim 11, wherein the pigment is an organic pigment. 13. The sheet according to claim 11 or 12, wherein the transferable medium contains a pigment dispersant and/or a fluidizing agent. 14. The sheet according to any one of claims 11 to 13, wherein the dye and pigment are present in a weight ratio of 90:10 to 10:90. 15. The sheet according to claim 14, wherein the dye and pigment are present in a weight ratio of 60:40 to 40:60.