FR2690873A1 - Pattern transfer sheet for colour pattern transfer - has a support layer and polyethylene@ film with an adhesive bond - Google Patents

Abstract

The pattern transfer sheet, for heat transfer, has a support layer and a film such as of polyethylene. An adhesive is sprayed on one surface of the film for bonding to the support. The structure is calendered so that the polyethylene film gives the right side of the image to be transferred with the film. The paper support can be peeled off after heat and pressure has been applied to bond the patterned sheet to the substrate. USE/ADVANTAGE - The material is for the transfer of coloured patterns or lettering by heat and pressure. The transfer is cheap and gives an effective patterning action.

Description

The present invention relates to the field of complex sheets used to receive polychrome prints or inscriptions and possibly capable of being transferred by thermal transfer to a final substrate.

We know complex sheets consisting essentially of a support including paper and generally coated with a plurality of surface layers capable of receiving markings in particular colored by various means which can then be transferred to a final substrate, in particular a fabric , and more especially a garment such as a T-shirt, the colored markings being applied to the receiving face of the fabric and impregnating the textile fibers by heat transfer by hot pressure, after which the paper support can be removed leaving on the definitive substrate the colored marking carried over definitively.

In the known techniques, a film is used of a material sensitive to heat, in particular thermoplastic, and having received the colored impressions and markings which are integral with or adhering to this material, which by thermal pressure is impregnated and imbedded in the textile fibers thereby ensuring the final deposition of the markings on the new textile substrate, the pigmented and marked parts being further protected from any external attack by the layer of hot-melt material deposited on the fabric, while the initial support paper can be peeled and removed.

The invention relates to developments in techniques for preparing such transfer sheets so as to considerably improve their performance while reducing the cost price and involving the production.

To this end, the invention relates first of all to a process for manufacturing a transfer sheet capable of receiving markings or possibly polychrome representations on one face of the sheet constituting its front and formed of a film transferable to heat, in thus allowing the transfer of inscriptions or representations on a final substrate such as a fabric, this in a manner known per se, and the method is characterized in that a support sheet is prepared on the one hand and a film or film of synthetic material such as polyethylene, an adhesive is sprayed onto one face of said film and the adhesive-coated side of said film is transferred to the support, after which the whole is calendered in order to obtain a filming whose polyethylene sheet constitutes the front receiving the transferable inscriptions with the film, the paper support being peelable after hot pressing and adhesion of the film e marked on its final substrate.

Preferably, calendering for lamination of polyethylene film paper is carried out at a temperature between room temperature and 600 C.

The adhesive preferably consists of a solution varnish.

And more especially the varnish is applied in the form of a spray of liquid / gas emulsion, in particular of mist or aerosol.

The invention also relates to a transfer sheet capable of being obtained according to the above method and characterized in that it consists of a support formed of a polyester film. Optionally, the support is made of paper, the receiving face of the polyethylene film having a polished and uniform surface finish and consisting in particular of coated paper, glossy paper, calendered paper or crystal paper. The support sheet comprises on its receiving face of the polyethylene film (covered with adhesive) a layer of a material which conducts heat, in particular a metallic film such as an aluminum foil, the layer of conductive material being obtained. in particular by vacuum metallization, from aluminum, steel, chrome.

According to an important development of the invention, the support sheet, in particular polyester, comprises on its receiving face of the adhesive-coated film a metallization layer obtained in particular by vacuum metallization, from aluminum, steel, chromium.

Even more especially, the adhesive is chosen with properties having a low affinity with polyethylene by allowing easy separation after transfer and by facilitating the peeling operation of the support sheet, the adhesive thus remaining present on the support sheet and being evacuated with the latter after peeling, leaving the polyethylene film in the naked state remaining outside, trapping on its surface the pigments constituting the markings or colored representations.

More particularly, the polyethylene film consists of a film with a thickness between 20 and 60 microns and preferably with a thickness close to 30 microns.

The invention also relates to the use of a transfer sheet, obtained according to the above method, characterized in that the deposit of inscriptions, representations or markings, in particular polychrome, is made on the bare face of the polyethylene film by markers of known type comprising pigment inks compatible with the polyethylene film, in particular based on organic solvents and in particular alcohol, oil, synthetic resin.

The invention also relates to the use of a transfer sheet, in accordance with the above process, characterized in that the filing of inscriptions or markings is done by automatic means possibly controlled by electronic or computer means, in particular by a thermal printer, deposition of ink by thermal sublimation, deposition of powdered pigments, printing from one or more photos, in particular offset printing.

The printing also relates to a kit for carrying out the transfer of the specified type, characterized in that it comprises at least one and preferably a plurality of sheets conforming to the above specifications and a plurality of means for writing or markings such as pencils capable of depositing compatible inks or pigments and having affinities with the polyethylene sheet.

According to yet another development, the invention relates to a method of implementing the transfer sheet according to the above characteristics and in which the sheet after receipt of the inscriptions, markings or colored representations, is applied to a final substrate such as a fabric by application of pressure and heat, such as an iron, for a period of the order of 15 seconds at a temperature of 1500.

Other characteristics and advantages of the invention will emerge from the description which follows and which is given in relation to a particular embodiment presented by way of nonlimiting example and with reference to the appended drawings in which
Figure 1 shows a schematic view of the continuous production of a transfer sheet according to the invention.

Figure 2 shows a cutout of said transfer sheet receiving by manual marking the inscriptions desired by the user.

Figure 3 represents the transfer of the sheet on a substrate such as a T-shirt, while Figure 4 represents the final product obtained that is to say the transfer of inscriptions on the garment such as the T-shirt .

Figure 5 shows a sectional view of a sheet for full color printing by a thermal printer and the
Figure 6 a variant for printing on color printer by sublimation ink.

It can be seen from the assembly of FIGS. 1 to 3 that there is a film coating suitable for making a transfer sheet from an assembly comprising a base support sheet 2 (FIG. 1) associated, preferably according to a advantageous embodiment, to a surface metallization layer 3 added by vacuum metallization.

On this base sheet 2 metallized at 3 is added the surface film 5 on which the adhesive layer 4 has been previously placed and in the interface.

The assembly can be made as expected using known techniques and as shown in Figure 2.

The support sheet formed of a polyester film 2 and comprising the surface layer of vacuum metallization is delivered by the coil 11 to a calendering assembly 12a, 12b.

This calendering assembly receives at the same time in the lower position from the reel 10 the polyethylene film or film of appropriate thickness, for example 30 microns.

On the face of the polyethylene film having to meet the metallic face of the sheet 2 is reported, by liquid emulsion in gas, a varnish diluted in an appropriate solvent from the nebulization assembly 13.

Thus, as can be seen in FIG. 2, the calendering device absorbs and joins together the sheet of metallized paper 2 on which the polyethylene film is attached.

According to a variant, the polyethylene film could be deposited, as soon as it extrudes on site, on the substrate formed from the metallized polyester complex.

The assembly is then routed downstream to a cutter assembly 14 to produce the stack 15 of the complex sheets according to the invention and as shown in FIG. 2.

This sheet is adapted to receive by surface transfer to the free face of the polyethylene film 5 markings for which the imagination or the source of inspiration of the user can give free rein.

These markings, illustrated in 6a, 6b, 6c, can be transferred by conventional means and manually, for example from marker pens whose ink is diluted in an organic solvent compatible with the polyethylene which thus receives the marking which becomes indelible after evaporation of the solvent on the surface of the polyethylene film 5.

Preferably, in the case of inscriptions, the markings 6b are produced in the form of images in a mirror of the definitive inscription.

We illustrated here the realization from a marker pen obtained manually.

However, any other form of registration by automatic means, in particular by a color thermal printer controlled by computer, or even sublimation of pigments, deposition of thermal powder, or else postponement by conventional printing processes; all these methods could be used as soon as the pigments or inks are compatible with the polyethylene sheet which receives them and stores them indelibly.

The implementation of the process beyond these phases is relatively conventional insofar as the preceding sheet, with the representations or markings appearing on its front, is applied to a support which must be its final substrate and which here consists of a T-shirt 7.

The transfer sheet, being applied to for example the chest of the T-shirt, requires a piezothermal application in the form of an iron maintained for 15 seconds at a temperature of the order of 1500.

One thus obtains a fusion or a softening of the polyethylene sheet which is imbricated in the meshes and fibers of the fabric and adheres to the latter by trapping between it and the fabric the markings previously described.

The metallized polyester sheet 3 can then be peeled, as seen in Figure 3, and removed leaving the inscriptions on the fabric appear.

The invention thus makes it possible to produce a surprisingly simple transfer paper under efficient and economical conditions.

The dosage and selection of the varnish makes it possible to obtain sufficient adhesion of the polyethylene sheet to its metallized support, adhesion which however remains sufficiently limited to allow, after thermal application under pressure, the metallized polyester sheet to peel very easily.

As the adhesive constituent varnish has very low affinity properties for polyethylene, this varnish therefore remains integral with the metallized polyester sheet and the polyethylene thus appears bare and glazed, providing the whole with an exceptional shine and coloring appearance.

The whole can then be worn, subject to successive cleaning and washing, while keeping its beautiful appearance; the colored pigments trapped behind the polyethylene sheet resistant to any attack and retaining their coloration.

The interposition of a metallized layer between the support and the polyethylene sheet also provides a particularly satisfactory effect during and after application and transfer to the final substrate.

The metallized layer in fact makes it possible on the one hand to obtain a perfect polish of the support, so that the polyethylene sheet on its outer face remains uniform, glazed and polished, consequently offering maximum gloss while its inner face is nested. and perfectly secured in the fibers and meshes of the fabric.

The metallic interface makes it possible, surprisingly, to obtain this conservation of the regular and polished surface condition of the polyethylene sheet, while at the same time it allows regularization in the effect of heat distribution. .

And in the case of raster representations, for example by printing, the singular and discrete points of the frame arrive, by the softening effect of the polyethylene sheet and of the pigmented areas which it supports, to widen , spread out and join together, thus obtaining a regular shade forming a flat, possibly showing gradations linked to the presence of discrete spots relating to several pigmentations, or at different densities.

So that we obtain not only a beautiful appearance in the brightness and the polish of the image, but also a perfect regularity in the respect of nuances, the quality obtained after transfer of the image on its substrate being superior to that of the initial support and reaching that of a photographic quality.

The use of a transfer sheet using a metallized complex, in particular polyester / aluminum / polyethylene has moreover a certain number of specific advantages.

It is inert to humidity and therefore dimensionally stable; it does not undergo any parasitic phenomenon linked to storage in humidity, for example a curled presentation.

Above all, the transfer to this polyester / aluminum / polyethylene complex has the advantage of allowing transfer and transfer of the polyethylene film supporting pigments at a lower temperature than in the case of the intermediate support sheet made of composite paper with polyethylene film.

It is in fact easily understood that the contribution of heat being made by the rear face of the sheet of paper, the intermediate metallized layer according to the invention constitutes a screen which regulates and distributes the contribution of calories to the polyethylene sheet, allowing its softening and its soft and regular impregnation on the secondary support or the definitive support in particular textile.

Due to a more regular and less sudden transfer of heat, the pigments adhering to the face of the polyethylene film in contact with the receiving substrate (for example textile) are less attacked and less risk of chemical or physical degradation; thus, thanks to the polyester / metal / polyethylene complex of the transfer sheet of the invention, the colors are respected and restored exactly after transfer to the final substrate.

The transfer support according to the invention formed of a polyester film complex metallization layer, coated with a polyethylene film allows peeling of the support cold after transfer has ended, which allows successive transfers to the same substrate by pressing. by removing the transfer sheet at the end of the operations.

Experience also shows that the images or representations thus obtained resist not only successive washing but aging, in particular to severe physical conditions such as heat or exposure to light.

It is thus possible, at the disposal of the layout designers, to make kits allowing the configurations which are envisaged to be carried over to projects, packaging, covers, etc., with different coloring tests.

The invention also makes it possible to produce, at low cost, transfer sheets made available, for educational purposes, to pupils or children of schools thus called upon to produce representations, drawings and symbolic images which can then be transferred to t-shirts. thus allowing everyone to display a characteristic image of their character or the personality they want to represent.

The invention also makes it possible to make such a sheet available to users in a catalog or a journal, either with a pre-print which will therefore make it possible for example during electoral campaigns or opinion campaigns to affirm or to display, for example on an item of clothing, an opinion on a specific subject.

The advertising applications of the invention are also very numerous, again allowing the provision and distribution to the public of inexpensive supports possibly including a pre-printed advertising message capable of being completed by each user according to their tastes. personal.

The invention also makes it possible to edit, in limited series, garments bearing inscriptions or representations, for example on the occasion of a local event or a one-off advertising campaign (a neighborhood store or an association of locally limited obedience which can thus, inexpensively and without incurring the expense of publishing a series of printed t-shirts, make clothing, in particular t-shirts, in a limited but sufficient quantity to respond to an event or a local or ad hoc campaign).

Among the various methods of application of the invention, there will be mentioned in particular the possibilities of producing intermediate support sheets or sheets comprising "pass partour" or "standard" patterns or representations, which can thus be produced in advance in stored quantities and marketed in standard formats and then used as needed.

It is thus easy and possible within the framework of the invention to produce intermediate support sheets comprising representations such as letters or symbols in particular pictograms, or standardized signage.

These standard sheets can then be easily purchased for making large inscriptions using any support on site and a pressure and heating element as simple as an iron.

It is thus possible to produce transfer sheets comprising large letters; by choosing the suitable letters, it is possible, by successive transfers, to make an inscription constituting a calico, this at an extremely low cost price.

This temporary banner can therefore be quickly available, for example during an exhibition or specific circumstances (sales, change of direction, public outdoor event, local advertising, etc.).

The transfer letters or transfer inscriptions thus produced on the intermediate support sheet of the invention can make it possible to carry out provisional inscriptions very quickly and under particularly economical conditions, for example when a markup stand is being held. a route, it is possible to perform on the walls of the stand representations, inscriptions, symbols by simple reports from the intermediate support sheet suitably made in advance and selected according to the circumstances.

But it is also possible, from the intermediate support sheets of the invention, to make definitive inscriptions of perfect aesthetics, for example on a shop window, a sign from a point of sale.

This avoids having to use the manual work of the "letter painter" or the technique of transferable letters after laser cutting.

The supports which have been mainly considered are of a textile nature, but the invention is not limited to this application.

In the first place, supports of a textile or paratextile nature such as nonwoven fabric (based on various fibers possibly associated with organic binders) can be used in particular in the context of a fleeting realization linked to a specific exposure.

It is also possible to use, outside of the fabric, a paper or cardboard support or a support made of synthetic material, wood, glass, metal or any support on which the softened polyethylene sheet will adhere.

Various arrangements, variants and embodiments can be developed and implemented using the elements previously described.

The deposition of the varnish on the face of the polyethylene film can be carried out as a variant in a liquid phase and by passing the polyethylene sheet over a source of varnish with the use of doctor blades or distribution cylinders or even by the implementation of doctors made up of threaded rods of known type and ensuring an equal distribution of the quantity of liquid product on the surface of the moving sheet.

According to yet another development of the invention, the polyethylene sheet could also be produced by extrusion immediately upstream of the lamination operation, the polyethylene sheet at the end of the extrusion being directly attached to the support sheet, in particular paper and more particularly in metallic paper.

The printing methods aimed at producing the images intended to be transferred to the final substrate are not limited to the methods previously listed and any mechanical printing, in particular offset but also typographic, heliographic, screen printing, flexographic printing, could be implemented.

The invention also relates to a more specific application of the polyester / metallized layer complex according to the invention and intended to serve as a support sheet for direct printing by computer-controlled printer, either a thermal printer or a sublimation printer.

There is shown in Figure 5 a sectional view of a sheet according to the invention capable of being used to receive a colored print from a thermal printer controlled by computer.

The sheet consists essentially of a core formed by a layer or a polyester film.

And unlike previous uses, the sheet no longer includes paper support here.

The central polyester layer 20 includes a vacuum metallization layer obtained from metal such as steel, aluminum or chromium. This layer 21 gives the sheet its metallized appearance known per se.

The metallization layer constitutes the front intended to receive the colored pigments.

Optionally, above this layer, you can add a uniform colored veil, especially white, when you want to work on a white background support; this veil, in particular the upper white 22, attached to the front consisting of the metallized layer 21 can be obtained by any means and the thickness of this layer will make it possible to measure the light effect and the coloring by finding a balance between the background color which is sought after and the effect of luminosity coming from the return of light radiations from the lower metallization layer 21 forming a reflecting mirror and consequently giving the sheet an exceptional luminosity and richness of coloration.

In the lower sublayer, the polyester sheet 20, with a thickness of between 50 and 180 microns, and preferably around 100 microns, can receive an antistatic layer 23 making it possible to facilitate the passage of the sheet through the machine.

Figure 6 represents a sheet intended for a polychrome printing on a machine controlled by computer and bringing back the colored pigments by thermal sublimation.

The sheet has the same elements and the same characteristics as what is shown in FIG. 5 with the particularity of receiving in the upper layer, constituting a receiving interface for the colored pigments, a veil of a cellulose varnish preferably in aqueous solution 24 .

The sheets and cutouts thus produced have remarkable conformational stability and in particular avoid the curling effect, that is to say the well-known curving of the paper-based printing sheets; the sheet of the invention, after passing through the machine, remains perfectly flat.

The sheets and supports thus printed can be kept for their value and their fine image.

The quality obtained, in particular in the context of a thermal sublimation machine, reaches the quality of a photographic reproduction.

In the case where the reproduction is intended to be transferred to another support, in particular to a clothing textile support, use will be made of a sheet having received a surface coating of a polyethylene film which constitutes the support receiving the pigments, either directly (in in the case of a colored thermal printing machine), or with a surface coating of cellulose varnish in the case of a thermal sublimation printing machine.

And the invention then makes it possible to obtain in a new way a transfer to a textile of an image reproduced initially on its support of the invention by thermal sublimation having a photographic quality, a quality which is found entirely in the report on the textile.

The quality of the reproduction comes in particular from the reaction and the physical properties of the metallization layer reacting in particular during the thermal transfer of the pigments, the conductive properties of the metallization layer being added and providing a synergistic effect to the rigorous flatness of the receiver support.

Claims (12)

1 - Process for the preparation of a transfer sheet capable of receiving imprints, markings or possibly polychrome representations on one face of the sheet constituting its front and formed of a film transferable to heat, thus allowing the transfer of inscriptions or representations to a final substrate such as a fabric, this in a manner known per se, and the method is characterized in that a support sheet is prepared on the one hand and a film or film of synthetic material such as polyethylene, an adhesive is sprayed onto one side of said film and the adhesive side of said film is transferred onto the support, after which the whole is calendered in order to obtain a film coating of which the polyethylene sheet constitutes the front receiving inscriptions transferable with the film, the paper support being peelable after hot pressing and adhesion of the marked film on its defined substrate if. 2 - Process according to claim 1, and characterized in that the calendering for the lamination of polyethylene film paper is carried out at a temperature between room temperature and 600 C. and the adhesive consists of a solution varnish applied in the form projection of liquid / gas emulsion, in particular of mist or aerosol. 3 - Transfer sheet capable of receiving markings or possibly polychrome representations on one face of the sheet constituting its front and formed of a film transferable to heat, thus allowing the transfer of the inscriptions or representations on a final substrate such as fabric, characterized in that it comprises a support, one face of which has a polished and uniform surface condition and capable of receiving a polyethylene film, itself covered with an adhesive film, the surface state being obtained by coated paper, glossy paper, calendered paper or crystal paper. 4 - transfer sheet according to claim 3, characterized in that the support consists of a polyester film and comprises on its receiving face of the polyethylene film, a metallization layer obtained in particular by vacuum metallization, from aluminum, steel or chrome. 5 - Transfer sheet according to one of claims 3 or 4, and characterized in that the adhesive is chosen with properties having a low affinity with polyethylene by allowing easy separation after transfer and by facilitating the peeling operation of the support sheet, the adhesive remaining present on the support and being removed with the latter after peeling, leaving the polyethylene film in the naked state to remain outside trapping on its surface the pigments constituting the markings or colored representations. 6 - Transfer sheet according to one of claims 3 to 5, and characterized in that the polyethylene film consists of a film of thickness between 20 and 60 microns and preferably of thickness close to 30 microns. 7 - Transfer sheet according to claim 3, characterized in that the support comprises, on-its receiving face of the polyethylene film, a layer of a: heat conductive material, in particular a metallic film such as a aluminum foil, backing sheet and metal sheet  forming a complex sheet.  8 - Use of a transfer sheet, according to one of claims 3 to 7 above, characterized in that the filing of inscriptions or markings is done by automatic means possibly controlled by electronic or computer means, in particular by a thermal printer, deposition of ink by thermal sublimation, deposition of pulverulent pigments, printing from one or more photographs, in particular offset printing. 9 - Sheet for receiving colored prints by a thermal type printer machine, and for implementing the method according to claim 1, the sheet consisting of a core formed of a polyester film of a thickness included between 50 and 180 microns and preferably of the order of 100 microns (20) to which a metallization layer (21) is added, in particular from aluminum, steel or chromium, the metallization layer constituting the front receptor for pigments thermally transferred by the machine. 10 - Sheet for colored prints according to claim 9, characterized in that it further comprises, above the metallization layer (21) a particularly white colored veil (22). 11 - Sheet according to claim 9, for colored prints from a computer-controlled printer and operating by thermal sublimation, characterized in that it consists of a core formed of a film (20) of polyester of a thickness of between 50 and 180 microns and in particular of the order of 100 microns on the front of which a metallization layer (21) is added, in particular from aluminum, steel or chromium, the metallization layer (21 ) comprising a surfacing obtained from a cellulosic varnish, in particular in aqueous solution (24). 12 - Sheet for colored printing according to claim 11, characterized in that it comprises above the metallization layer (21) a particularly white colored veil (22) then receiving the cellulosic surfacing receiving pigments deposited by sublimation.