AU2425588A - Process for transferring motifs applied by dye to one motif carrier on to another carrier, in particular textiles - Google Patents

Abstract

In a process for transferring motifs applied by dye to one motif carrier on to another carrier, in particular textiles which can be washed at temperatures up to 95C, the motif side of the motif carrier is brought into contact with the other carrier. Transfer is effected by means of transfer fluid and under pressure. The motifs are produced from a laundry-fast dye or from a dye which is rendered laundry-fast by admixture with an additive during transfer.

Description

Transfer of ink-applied motifs from a motif substrate to

another substrate. in particular textiles

The present invention relates to a process f or

transferring ink-applied motifs from a motif substrate to another substrate, in particular textiles which are

washable at up to 95"C, by bringing this motif substrate with the motif side into contact with this other sub strate and effecting the transfer by means of a transfer liquid and under pressure. In textile printing technology it is known to

print a black and white or colored image onto a first image carrier, for example a sheet or strip of paper, and to print the image from this image carrier in a second

step onto the final substrate, in particular a textile

fabric. These processes are referred to as transfer

printing processes. They are carried out either as damp transfer processes or as dry transfer processes. In the

damp transfer process, a prefinished paper is printed

with dye and resin. The transfer takes place on a calen der at high temperature under pressure and with simul

taneous exposure to the vapor of a suitable agent. In the

dry transfer process, the paper is printed with pigment colorant and a thermoplastic synthetic resin, so that the

transfer can be carried out at elevated temperature on a hot calender without additional vaporing agent. Problems arise here in particular due to the

necessary elevated temperature with which the textile

fabric needs to be treated. As a consequence of this

elevated temperature, the textile fabric becomes register prob distorted, so that there are appreciable The individual colors no lems in the transfer of colors.

or flow into one another. Furthermore, longer coincide unsuitable for transfer these processes are completely produced by a conventional ring for example an image printing process here is printing process. A conventional or flexographic print understood as meaning letterpress intaglio printing ing, planographic or offset printing, printing. In or knife intaglio printing and screen to be printed are letterpress printing, the elements is flat or cylindrical. raised while the printing plate and non Planographic printing, where printing same plane, is based on the printing elements are in the by fact that the printing areas are made water-repellent

treatment. They can be inked with a pasty chemical areas are made oil printing ink; the non-printing absorb any printing ink. The repellent, they do not printing) or printing plate is either flat (lithographic The inking unit is com cylindrical (offset printing). the lithographic bined with a damping unit which moistens

or offset plate before inking. elements are .In intaglio printing, the printing

by etching or engraving. The printing plate, recessed has the excess of ink which is flooded with liquid ink, a doctor blade, so that removed from it, for example by printing elements. The ink remains only in the recessed by a printing paper is pressed against the printing plate the ink is sucked out of cylinder, as a result of which the wells onto the paper. plate consists In screen printing, the printing (metal or nylon of a- screen of ink-permeable material is forced manually or in screen). The pasty printing ink a squeegee through a screen printing press by means of printing stock. Neither the holes of the screen onto the transfer process are the damp transfer nor the dry as are produced by suitable for transferring such images conventional printing processes. 1,771,863 describes a DE Offenlegungsschrift known process whereby images produced on an original are conferred to a new substrate, for example art paper, made of textile mat substrate, for example a surface erial, wood, stone or the like. In this form of transfer, an intermediary support which is not moisture is used in the form of a laminate the following layers in sensitive and which consists of a soluble middle the stated order: a support layer, layer layer, a clearcoat layer and a pressure-sensitive of this process of sizing substance. The disadvantages of image transfer and are in particular the inaccuracy image areas. Further the presence of badly transferred extremely compli more, the intermediary substrate is an cated object. then described in DE According to the process these difficulties are Offenlegungsschrift 1,771,863, layer which covers the avoided when the printing ink of adhesive and when a sheet image is coated with a layer a pressure-sensi or the like which has been coated with the adhesive side tive sizing substance is pressed with whereupon the sheet or against the printing ink layer, is peeled off the printing ink layer, leaving the like behind the sizing substance, and the sizing substance has it a previously prepared intermediary pressed onto is not moisture-sensitive and which con support which above the other, viewed from the pressure sists one sizing substance, of a clearcoat layer, an sensitive is readily detachable from the adhesive layer which support clearcoat layer, and a base layer, for example of whereupon material or some other support material [sic], the original support is removed from the printing ink support is applied with the layer and the intermediary the new support, printing ink layer present thereon onto support and whereupon the base layer of the intermediary layer. the adhesive layer are removed from the clearcoat

It is immediately apparent from the description known process is not of these complicated steps that this of motifs to a in any way suitable for the mass transfer much too compli large number of articles. The process is a lot of time cated and resource-intensive and requires and costly inter and skill on the part of the operative

mediary substrates. the transfer GB Patent 423,727 likewise describes surface. Here of images from a first surface to a second a fluid which softens the starting motif is treated with the intermediary substrate. The the surface of in intermediary substrate is paper which has been coated a complex and resource-intensive manner with various substances. Thereafter the original motif chemical causes substrate is treated with a further reagent which the substrate to dissolve, so that the substrate becomes from the motif then present on the inter detachable mediary substrate. Finally, the motif is then transferred

The from the intermediary substrate to the new substrate.

fluid applied to the original motif is a fluid which

a fluid dissolves the original substrate for the-motif or

which softens the surface of the intermediary substrate.

This process too has the above-described disadvantages. makes A process described in DE Patent 2,757,630 a printing it possible for the first time to transfer, by from a flexible process, conventional printing ink motifs original substrate, for example a printed paper, to a new

substrate, in particular a leather or wood substrate, the

motif being detached from the original substrate by

application of a liquid.

In this process, the new substrate is wetted with

ink-dissolving liquid, preferably a neutral non an

alkaline nonionic surfactant and oil and hydrocarbon

is containing solvent. Thereafter the original substrate onto the wetted placed with the side bearing the motif surface of the new substrate and is pressed down thereon.

Finally, the original substrate is peeled off the new

substrate.

This process has admittedly appreciable advan

tages, but is essentially directed to the transfer of

photocopies and does not meet industrial requirements, in

particular because of the low washability or low wash resistance and the low color quality or brilliance. It

has been found that in the printing of textiles it has

the significant disadvantage that the transferred motifs

become paler and paler with every wash. It is an object of the present invention to

eliminate the abovementioned disadvantages and in par

ticular to develop a process which permits inexpensive and rapid image transfer, in particular to textile

substrates, in such a way that the images become per

manent on these textile substrates. This object is achieved when the motifs are

produced in a washfast ink or in an ink which in the

course of the transfer has added to it an additive which renders the ink washfast. The two possibilities have equally advantageous

effects. Preferred washfast inks are oxidative inks.

These inks do not in general contain any hardener, but

harden .automatically within a predetermined period.

However, after hardening they are no longer detachable by an ink-dissolving liquid, so that they are then no longer transferrable from a motif substrate to another substrate either. For this reason, there are additives for these

oxidative inks which prevent hardening. It is thus within the purview of the invention that the motif is produced by means of oxidative inks and is transferred immediately or, depending on the retarding agent, within a predeter mined time to the other substrate. If, for example, a four-colored print is to be carried out, first the yellow plate is printed onto the motif substrate.

As soon as the yellow print has become hard at

the surface, the blue plate is printed, followed after

the surface hardening of the blue print by the red plate

and finally the print with the black plate. This sequence

is merely illustrative and can be varied in the interests

of the process. A motif produced in such a way can then

be used at once and for example be placed onto a T-shirt.

On application of the transfer liquid the hardened

surface of the ink is broken, and the ink can penetrate into the textile fabric. The transfer liquid also dis

rupts the hardened surfaces of the subsequent ink layers,

so that they can likewise penetrate into the textile.

Once on the textile, relatively rapid hardening takes

place because the oxidative ink is now exposed to the air

on all sides and can harden more rapidly.

.The same is true of paper is used as the motif

substrate. Here too the oxidative ink hardens not only

from the surface but also from the back through the

paper. The situation is different, however, if the motif

is applied for example to a foil because in this case the

oxidative ink is not exposed to the air from the back. The motif substrate thus also determines the shelf life of the oxidative ink motifs.

All this must be taken into account in particular so that this re in the addition of a retarding agent, in the use of oxidative inks. quires certain experience for by However, this slight disadvantage is compensated without the addition of har the high wash resistance

dener. ink is in However, the advantage of an oxidative fine microstructures become particular also that very accuracy. In this transferrable with 100 percent register any waste material, as way the process does not produce is the case with the existing processes. The correspond the inks form a very ing cost saving is 60 to 80%. Since

firm bond with the textile substrate, they, once hard,

can be chemically treated or hot pressed without impair

ing the motif in any way. the process is A further appreciable advantage of

that the transfer of the motif takes place completely

material can without added heat, so that even synthetic material conse be treated. Cotton as well as synthetic dimensional change, so that quently does not undergo any cannot be distorted either. The image is the motifs

transferred to the textile substrate completely colorfast

number of washes. and persists through a large the production Whereas it used to be necessary in by four-color of for example 100 newly printed substrates to take place, the printing for 400 printing operations that is, for example present process is highly efficient; the screen is exposed 100 times in screen printing, proof and through the screen with the drawn reproduction four printing 100 four-colored motifs are produced in each motif then requires a operations. The transfer of the total to 104 further printing operation. This brings alone indicates the substantial prints. This number saving in time, since 296 prints fewer are necessary. Motifs produced in this manner, more correctly motif substrates, are safely storable, motif-bearing which in turn leads to an appreciable cost saving. that On a fundamental note it must be stressed it was not possible to using the earlier processes print to a textile transfer for example a four-colored that material by one of the transfer processes mentioned; of an image is, it was not possible to print an original distortion, register onto a certain substrate. Fabric the direct transfer of an problems and the like prevented for example, since the original four-colored print with a so-called carrousel. printing was generally done consists of at In four-color printing, the carrousel of which one color least four individual stations in each A manual carrousel is applied to the printing substrate. while an automated requires at least five operatives, the register carrousel requires at least two. However, carrousel accuracies are even worse with the automated due to the constant than with the manual one. This is stations. Even need to center the corresponding carrousel which occurs as the the small degree of fabric distortion lifts off leads to a register preceding carrousel station subsequent carrousel inaccuracy in respect of the costs for a manual station. In addition, the acquisition high, as are the fixed or automated carrousel are very costs for the corresponding personnel. What is more, a carrousel takes up significantly more space. it is possible to However, by the present process also physical inks. These use not only oxidative inks but inks, can be redissolved physical inks, unlike oxidative and motifs produced there by an ink-dissolving liquid, life. This is also with therefore have a longer shelf diluent which is added connected in particular with the during drying. How to physical inks and which evaporates with all other inks. ever, the process is also possible proppps As for the rest, it is immaterial for the technique according to the invention by which printing The motif can be produced the desired motif is produced. printing not only by letterpress printing, planographic screen printing. In each or intaglio printing but also by to seek out the most cost case, it will be necessary is able to produce the effective option. Every printer obligation to buy motifs himself, so that there is no inks. Both oxi from a certain source as with existing readily avail dative and physical inks are commercially able. the Preference is incidentally given to printing that, after the transfer motifs the wrong way round, so round. This is to the substrate, they are the right way in fact the essential difference from the process des a transfer takes cribed in DE Patent 2,757,630, wherein This prior art process is place the wrong way round. i.e. motifs which generally used to transfer photocopies, are the right way round, to a substrate the wrong way round.

However, for the present process the very oppo motif itself the site is intended, namely to produce the to the T-shirt or wrong way round, so that the transfer way round. The the like gives an image which is the right round also makes fact that the transfer is the right way

script characters onto an appro it possible to print transferred with the priate substrate. The printing inks process adjust to every textile fiber, abovementioned

i.e. not only a natural fiber but also a synthetic fiber,

with full retention of the color brilliance of the image.

substrate is washable without limitations, the The wash resistance. transferred image showing a very high

The transfer liquid to be used is in particular

of an organic solvent as men a liquid which consists for example in DE Patent 2,757,630. They are tioned totally nontoxic. commercially readily obtainable and are by fatty The highest suitability appears to be possessed

acid esters, specifically butyl acetate. this solvent may have added to it an Furthermore,

orange oil, which has proved to be oil, in particular particular as regards the particularly advantageous, in lights and color fastness of the transferred motif.

The further proposed additive soybean lecithin

concentrate, which is a detergent-active substance,

ensures that the surface tension not only of the new

substrate, for example the textile fiber, but also of the

original motif substrate, i.e. the image surface, is

reduced and hence that better wetting takes place.

To neutralize the odor of the proposed transfer

liquid, which in some cases is considered unpleasant, the

solvent has further added to it citric acid, in an amount

to ten percent by volume. However, to prevent of up

overacidification of the solvent on the other hand, which

can lead to damage of the wetted surfaces, the solvent

has in turn added to it a salt which brings about

neutralization.

It has further been found, surprisingly, that the

addition of an oak bark extract to the solvent leads to and its an appreciable improvement in the image quality durability.

Finally, the inventor has found from long experi

ments that an addition of so-called litanide brings about

improvement in the image quality after a significant process complete evaporation of the transfer liquid. The

leads in particular to an appreciably higher wash resis

tance; tannic acid migration is likewise substantially

eliminated, so that the image quality on leather or the

like is likewise significantly improved.

If certain inks are used to produce the motifs, hardener to the ink it can prove to be necessary to add a

itself or to the transfer liquid in the course of the

process.

The latter option is preferred because a motif in

by the an ink without hardener is more easily detachable and the hardener transfer liquid from the motif substrate inks on a substrate is not added until stability of the soluble on the is desired, so that the inks are indeed after transfer to motif substrate but are made insoluble the hardener in the the textile substrate by addition of

transfer liquid. increase Further innovations connected with the

resistance concern the motif substrate in the wash substrate harbors itself. As indicated above, the motif of the hardening of appreciable uncertainties in respect when it is made of an in particular oxidative inks cellulose material, i.e. when for example absorbent

normal paper is used. Even in this case there are such

from paper to paper that it is very large differences needs to be difficult to lay down how much of a retarder

added to the ink for it not to become hard within a

predetermined period. proposes a motif The present invention therefore of different substrate formed from at least two layers prefer densities. The layer which bears the motif should On the other hand, ably be impermeable to the motif ink. liquid. The it should be permeable to the transfer here to be possessed highest suitability has been found commercially available by a motif substrate which is under the name Chromolux paper. Chromolux paper consists of paper coated on one side forming a closed surface which side, the coated prevents penetration of the motif ink. From the back,

Chromolux is like a permeable paper. If the transfer

liquid is applied to this layer, it penetrates the coated the side from the back as well and incipiently dissolves motif ink which is then transferred to the new substrate. The transfer liquid can be applied by various on methods, the particular method depending in particular the motif substrate and the new substrate. Of possible

methods, impregnating, spraying or spread application coating must be considered equivalent. In non-industrial wetting production, i.e. in series production [sic], the be sufficient. by means of pens or sprayers can also These pens at the same time exert pressure on motif

substrate and new substrate. Furthermore, spongelike

in which case a applicator means are also conceivable, certain portioning of the transfer liquid to be applied should follow. For example, appropriate portioning takes a solid material place when the application means used is forms having a nonplanar surface. The nonplanar surface its holes in which the transfer liquid stays by virtue of the own forces of adhesion and is only sucked off as solid material is placed on the motif substrate or the

new substrate. In individual cases it can prove to be advisable to transfer the transfer liquid through a nonwoven. This reduces the amount of liquid to be applied, which leads to a further cost saving.

For the purposes of the present invention it is

immaterial whether the motif substrate is placed on the

new substrate or the new substrate is placed on the motif

substrate. Furthermore, it is also possible to place

motif substrate and substrate against one another and to

exert pressure from both sides. The invention is not

limited in any way in that respect.

In a later industrial process, it is proposed to

guide the motif substrate over rolls impregnated with

transfer liquid and then to introduce the motif substrate

together with the new substrate into a nip formed by two

pressure rolls. In this way it is possible for example to

print continuous webs of wallpaper in industry.

The process according to the invention is herein

after briefly illustrated once more by reference to the

drawing, which shows in its only figure a schematic block

diagram of the process according to the invention for

transferring ink-applied motifs from a motif substrate to

another .substrate, in particular textiles.

In a first process step, a motif is applied to a motif substrate, for example by four-color printing. The

particular printing method is not important; preferred

motif substrates are described above.

This motif substrate is brought into contact in

a press with the surface or new substrate to be printed, which has been wetted with transfer liquid shortly beforehand or is wetted with transfer liquid in the course of placing into the press. The transfer liquid incipiently dissolves the motif ink and bonds to the new substrate, the process of bonding being speeded up and improved by additional pressure.

After the press has been opened, motif substrate

and new substrate are separated from each other, with the

motif remaining adhered to the new substrate.

Which presses are used for the present process

according to the invention is immaterial. They can be

hydraulic, pneumatic, electromagnetic or similar presses.

Even manual pressure, as exerted for example when images

are transferred by means of ink-dissolving liquid present

in pens, is sufficient in individual cases. Depending on

which quantities or numbers of printed substrates are

produced, the press will likewise be adapted to the

necessary requirements. The range can extend up to fully

automatic presses operated in three shifts. Here too there is a clear manifestation of the advantage that the

image to be transferred, irrespective of how many prints

it consists of, is transferred as a whole and there are

consequently no register problems which could be elimi

nated only to a small extent by additional human

intervention.

Not only motif substrates but also ink-dissolving

liquid and presses are easily handleable materials and

objects. This makes it possible to fit out a mobile printing works which on request makes on-site visits to apply prints also for example to immobile or difficult to-move objects. It is always possible, using an appro priate press, to apply motifs also to walls, tables, chairs and the like. The effect may be summarized once more as fol lows: No existing process, irrespective of whether it is a damp transfer, a dry transfer or for example a hot transfer process, makes it possible to transfer original images to any desired substrate. Existing printing processes only make this possible directly on a printing press itself, but these printing presses are costly and therefore only utilizable in industrial processes.

Furthermore, images printed directly for example onto a textile substrate by a printing press leave a lot to be desired in respect of crispness, register accuracy and

even depth of field or color brilliance. The process according to the invention, by

contrast, makes it possible for the first time to trans

fer an original image, whether it is a print, a photo

graph, a photocopy, a row of characters or the like,

directly from a motif substrate to another substrate.

This opens up a completely new industry, since this

process can be used not only by private persons, such as craft workers, and small businesses but also by large

businesses.

It is here completely immaterial whether the intention is to transfer an image which has been produced in asingle-color or in a multi-color print. Crispness, register accuracy and, in the case of black and white images, the depth of field correspond to those properties of the original image.

Since the process does not employ any heat, no distortion of the printing substrate takes place either, so that this substrate retains the same shape before and after printing.

The image applied to a washable substrate is resistant to washing irrespective of whether it is a natural or synthetic substrate. The same is true of dry cleaning, which likewise cannot harm the image. Ironing

is perfectly possible.

Emphasis must be given in particular to the low costs, and the low space and personnel requirements. Any private person is able by himself to transfer desired images to any desired substrate, but it is also possible for any printer to produce his own motifs and to apply

these rapidly and without waste to substrates in short and long runs.

Claims (1)

1. A process for transferring ink-applied motifs

from a motif substrate to another substrate, in par ticular textiles, which are washable at up to 95*C, by bringing this motif substrate with the motif side into

contact with this other substrate and effecting the transfer by means of a transfer liquid and under pres

sure, which comprises producing the motifs in a washfast

ink or in an ink which in the course of the transfer has

added to it an additive which renders the ink washfast.

2. A process as claimed in claim 1, wherein the motifs are produced in an oxidative ink.

3. A process as claimed in claim 2, wherein the oxidative ink has added to it an additive which prevents

hardening of the ink.

4. A process as claimed in claim 2 or 3, wherein the motif is produced the wrong way round by four-color printing, in which case the particular successive colors

are applied immediately after the brief drying of the

preceding color.

5. A process as claimed in claim 1, wherein the motifs are produced in physical inks.

6. A process as claimed in claim 5, wherein the physical inks are admixed with a diluent in such a way that they are redissolved by the transfer liquid.

7. A process as claimed in at least one of claims 1

to 6, wherein the transfer liquid has added to it a hardener for the inks.

claims 1 8. A process as claimed in at least one of of to 7, wherein the transfer liquid consists essentially an organic solvent. as claimed in claim 8, wherein the 9. A process formula solvent is a fatty acid ester of the general 2 R 1-C-0-R

0

where

R 1 is hydrogen or alkyl of 1-6 carbon atoms or hydroxy

ethyl and of 2 or 3 R 2 is alkyl of 1-6 carbon atoms or hydroxyalkyl

carbon atoms or one or two free hydroxyl groups.

A process as claimed in claim 8 or 9, wherein the 10.

solvent is butyl acetate.

11. A process as claimed in any one of claims 8 to

10, wherein oil is added to the solvent.

12. A process as claimed in claim 11, wherein the oil

is an orange oil, sweet. 3-4 ml 13. A process as claimed in claim 12, wherein

of orange oil are added per liter of solvent. claims 8 14. A process as claimed in at least one of it as a surfac to 13, wherein the solvent has added to in an tant a soybean lecithin concentrate, preferably

amount of 3-5 grams per liter of solvent.

15. A process as claimed in at least one of claims

to the solvent. 8-14, wherein citric acid is added the 16. A process as claimed in claim 15, wherein to 10% by volume. proportion of citric acid is up

17. A process as claimed in at least one of claims 1

to 16, wherein salt, preferably sodium chloride, is added

to the solvent.

18. A process as claimed in at least one of claims 1

to 17, wherein oak bark extract is added to the solvent.

19. A process as claimed in at least one of claims 8

to 18, wherein litanide is added to the solvent.

20. A process as claimed in at least one of claims 1

to 19, wherein the motif substrate is formed from at

least two layers of different densities.

21. A process as claimed in claim 20, wherein one

layer is impermeable to the motif ink.

22. A process as claimed in claim 21, wherein one or

other layer is permeable to the transfer liquid.

23. A process as claimed in any of claims 20 to 22,

wherein one layer is formed from cellulose while the

other layer is formed essentially of a plastic.

24. A process as claimed in claim 23, wherein the

motif substrate is Chromolux paper.

25. A process as claimed in at least one of claims 1

to 24, wherein the transfer liquid is applied by impreg

nating the motif substrate and/or the other substrate.

26. A process as claimed in at least one of claims 1

to 24, wherein the transfer liquid is applied by

spraying.

27. A process as claimed in at least one of claims 1

to 24, wherein the transfer liquid is applied by spread

coating.

28. A process as claimed in at least one of claims 1

to 24, wherein the transfer liquid is applied by wetting

by means of pens. 29. A process as claimed in at least one of claims 1 to 24, wherein the transfer liquid is applied by a

spongelike application means.

30. A process as claimed in at least one of claims 1 to 24, wherein the transfer liquid is applied by a solid material having a nonplanar surface.

31. A process as claimed in at least one of claims 1 to 24, wherein the transfer liquid is applied through a nonwoven.

32. A process as claimed in at least one of claims 1

to 31, wherein the motif substrate is placed on/against the other substrate or the other substrate is placed

on/against the motif substrate. 33. A process as claimed in claim 32, wherein the

contact pressure is produced by hand.

34. A process as claimed in claim 32, wherein the

contact pressure is produced by means of an automated

press, for example a hydraulic, pneumatic, electro

magnetic or similar press, in particular by means of a

pressure pad.

35. A process as claimed in claim 32, wherein the

contact pressure is produced between at least two rolls between which the motif substrate and the other substrate

are guided together.