EP0208257B1 - Procédé de métallisation par transfert - Google Patents

Procédé de métallisation par transfert Download PDF

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Publication number
EP0208257B1
EP0208257B1 EP86109038A EP86109038A EP0208257B1 EP 0208257 B1 EP0208257 B1 EP 0208257B1 EP 86109038 A EP86109038 A EP 86109038A EP 86109038 A EP86109038 A EP 86109038A EP 0208257 B1 EP0208257 B1 EP 0208257B1
Authority
EP
European Patent Office
Prior art keywords
hot
metallic layer
transfer
melt
lamination
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Revoked
Application number
EP86109038A
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German (de)
English (en)
Other versions
EP0208257A2 (fr
EP0208257A3 (en
Inventor
Alfred Schad
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hoechst AG
Original Assignee
Hoechst AG
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Filing date
Publication date
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Application filed by Hoechst AG filed Critical Hoechst AG
Publication of EP0208257A2 publication Critical patent/EP0208257A2/fr
Publication of EP0208257A3 publication Critical patent/EP0208257A3/de
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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B44—DECORATIVE ARTS
    • B44C—PRODUCING DECORATIVE EFFECTS; MOSAICS; TARSIA WORK; PAPERHANGING
    • B44C1/00—Processes, not specifically provided for elsewhere, for producing decorative surface effects
    • B44C1/10—Applying flat materials, e.g. leaflets, pieces of fabrics
    • B44C1/14—Metallic leaves or foils, e.g. gold leaf
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H19/00—Coated paper; Coating material
    • D21H19/02—Metal coatings
    • D21H19/04—Metal coatings applied as foil

Definitions

  • the invention relates to a transfer metallization method in which a metal layer is applied to a transfer medium and is transferred from it to a manufacturing body by lamination and subsequent delamination.
  • Such a method is already known from DE-A 2 907 186.
  • an extremely thin metal coating is applied to a film, then the metal layer or the carrier provided for coating is provided with a lacquer coating, and then the metal-coated film and the carrier to be coated are combined to form a laminate.
  • the lacquer coating is then allowed to harden, and then the carrier and the film are separated again.
  • the metal layer remains on the carrier, which leads to a mirror-like metallic surface with a highly polished appearance.
  • the so-called wet lamination process in which the curing time of the lacquer is shortened by the fact that the lacquer is largely dried by the application of heat after the layers have been brought together, has the disadvantage that the plastic film on which the metal layer is initially applied and by is applied due to the action of heat which is later to be separated again, is so severely impaired that reuse of the film is not possible or is possible only to a limited extent because the film shrinks and wrinkles occur in the process.
  • Hardening of the lacquer layer by UV rays which is also described, fails due to the impermeability of the support material provided for the coating, usually paper, or the reflection of the rays on the metal layer.
  • DE-A 2 015 623 describes a method for connecting and detaching a surface material to or from a base using a reflow material as a binder.
  • polyester films are also described as a base, but these still leave something to be desired in view of the desired easy removal of the surface material.
  • EP-A 0 175 259 describes as prior art according to Art. 54 (3) EPC a transfer metallization film made of polypropylene. An adhesive for metal transfer is not specified in this document.
  • the object of the present invention was to develop an economically advantageous process for the transfer metallization of manufacturing bodies, with which a rapid setting of the connecting layer, by means of which the metallic coating is fixed on the carrier material provided for the coating, can be made possible, with which in particular metallized Manufacturing body continuously, ie can be produced without intermediate storage, but in which the plastic film required for the transfer of the metal layer is nevertheless treated carefully and can therefore be reused as often as possible.
  • the metal layers used can be layers of one of the metals gold, silver, copper, nickel, tin, aluminum or mixtures or alloys of at least two of these metals, preferably of aluminum.
  • the metal layer has a thickness in the range from 10 to 200 nm. In order for the metal coating to give the manufacturing body a uniform surface gloss, it must have a high degree of homogeneity and must not have an island structure. A thickness of at least about 10 nm is required so that even after the metal layer has been transferred from the transfer medium to the manufacturing body, a discontinuous island structure does not arise, but rather a continuous structure is achieved.
  • the thickness should preferably not be more than 200 nm.
  • the particularly suitable thickness of the metal layer is in the range from 10 to 100 nm.
  • a film which has a metallic coating described above is known, for example, from DE-A 2 828 576.
  • Films made of polypropylene or polyester are used as transmission means in the context of the present invention.
  • a suitable film The basis of polypropylene is described, for example, in DE-A 3 434 298, suitable polyester films consist, for example, of polyethylene terephthalate, are biaxially oriented and heat-set. Polyester films have a coating on one or both sides, which is transferred to the paper during the transfer process because it can be easily removed from the polyester film. For example, lacquers based on nitrocellulose are used as coating agents.
  • sheet-like shaped bodies can be used as manufacturing bodies, in particular those which are in web, sheet or sheet form and have a rough or smooth surface.
  • Suitable materials from which the shaped bodies can consist are e.g. Paper, cardboard, wood, leather, rubber, plastic as well as any paintable material.
  • a hot-melt medium is to be understood as meaning various resins, some of which are also known under the name "hot-melt" (hot-melt adhesive).
  • hot melt adhesives usually consist of a combination of ethylene vinyl acetate copolymers with a low molecular weight resin or wax.
  • the ethylene-vinyl acetate copolymer imparts cohesion and binding power to the hot-melt adhesive and determines the viscosity and heat resistance; the resin additionally promotes the adhesive properties and essentially determines the color and smell of the hot-melt adhesive; the wax is the most crystalline component of the hot melt adhesive, which in particular also determines the softening point.
  • an oligomeric ethylene is used in combination with ethylene vinyl acetate copolymers.
  • hot melt adhesives consist of branched, low molecular weight polyethylene and other resins, including also atactic polypropylene.
  • Other hot melt adhesives made from thermoplastic block copolymers are also known which have more or less rubber-like properties.
  • Other hot melt adhesives based on polyamides or polyesters can also be used. The properties and compositions of hot melt adhesives are e.g. described by T. Quinn in "The 1984 Packaging Encyclopedia", pages 54 and 55.
  • the hot melt adhesive is normally applied in a liquid state at elevated temperatures.
  • the temperatures are usually in the range of 70 to 200 ° C, depending on the type of hot melt adhesive used.
  • the hot melt adhesive develops its maximum adhesion at temperatures below 50 ° C.
  • the time for the maximum adhesion to form, with appropriate cooling, is in the range from 0.2 to 50 seconds.
  • Devices for applying the hot-melt adhesive are described, for example, by C. Scholl in "The 1984 Packaging Encyclopedia", pages 209 to 211.
  • the layer thickness with which the hot-melt adhesive is expediently applied depends on the surface quality of the manufacturing body provided for coating. For very rough surfaces such as in the case of leather or foamed polystyrene materials, layer thicknesses in the range from 10 to 30 ⁇ m are appropriate, preferably from 15 to 30 ⁇ m, for comparatively smooth surfaces of substrates such as e.g. Plastic or paper can be used advantageously hot melt adhesive layers in the range of 5 to 25 microns, preferably from 15 to 25 11m.
  • the hot-melt adhesives can be applied either to the surface of the fabrication body intended for coating with metal or to the metal layer of the transfer medium or to both, using the method according to the invention.
  • the application method preferred according to the invention for hot melt adhesive is the roller application method.
  • the hot-melt medium is to be intermediate-extruded when the manufacturing body is brought together with the transfer agent carrying the metal layer, polyethylene or copolymers of polyethylene.
  • the polyethylene can preferably be plasticized in an extruder and is pressed through a slot nozzle exactly into the gap which is formed by the surface of the fabrication body intended for coating with metal and the metal layer on the transfer medium during the assembly.
  • the desired layer thickness of the polyethylene corresponds to the layer thicknesses already specified for the hot melt adhesive.
  • the temperature of the melt is 250 to 300 ° C.
  • the lamination of the manufacturing body provided for the coating, in particular the sheet-like shaped body in web form, with the transfer film carrying the metal layer is expediently carried out by bringing the webs together by means of rollers, preferably at elevated temperature.
  • bringing them together for the purpose of lamination by means of rollers is described for example in DE-A 2 907 186.
  • the lamination is carried out at an elevated temperature.
  • the temperatures which are preferably used in the lamination are in the range from 80 to 200.degree.
  • the specified temperature control causes, in particular, that the hot-melt medium on the one hand binds well to the metal coating and on the other hand has a sufficiently high viscosity to remove all unevennesses that are normally a certain roughness be able to fill the surface of the manufacturing body.
  • the laminate of manufacturing body, hot-melt medium, metal layer and transfer film is preferably cooled so that the hot-melt medium develops its maximum adhesive force more quickly, preferably the laminate is cooled to such an extent that the hot-melt medium solidifies and has a temperature below 60 ° C.
  • the cooling can be effected by blowing with cold air or by cooling rollers through which coolant flows; preferred to achieve faster cooling, both methods combined.
  • the transfer film After cooling, the transfer film is removed again from the laminate of fabrication body, meanwhile solidified hot-melt medium, metal layer and transfer film.
  • the metal layer held by the cooled hot-melt adhesive or the cooled polyethylene, adheres to the manufacturing body and gives it a metallic, highly polished appearance.
  • the transfer film can be used again in the process. The delamination is also done on rollers as described in DE-A 2 907 186.
  • metallized moldings in particular paper webs, can be produced economically in a continuous process, which have a decorative appearance and in which the metallic layer adheres permanently to the paper base.
  • FIG. 1 shows a schematic representation of a method according to the invention, in which a hot-melt adhesive is applied to a sheet-like shaped body and in which a metal layer is then transferred from a film to the sheet-like shaped body.
  • FIG. 2 shows a schematic representation of a method according to the invention, in which polyethylene is extruded from a slot die between a sheet-like shaped body and a metallized film.
  • the paper web 1 used as a sheet-like shaped body is coated with hot-melt adhesive 4 at the roller station 5/5 '.
  • the paper 1 coated with hot-melt adhesive 4 then arrives at the roller station 6/6 ', in which the lamination of the paper web 1 coated with hot-melt adhesive 4 with the foil 2 made of thermoplastic plastic carrying the metal layer 3 is carried out.
  • the rollers 6/6 ' are preferably heated.
  • the laminate of plastic film 2, metal layer 3, hot-melt adhesive 4 and paper web 1 is passed on from the roller station 6/6 'to the roller station 7/7', at which the plastic film 2 is pulled off the laminate again.
  • the paper web 1 coated with the adhesive layer made of hot-melt adhesive 4 and the metal layer 3 is wound up on a winding station (not shown) or fed straight to further processing.
  • FIG 2 taking into account the individual reference numerals, it is shown how, according to the method according to the invention at the roller station 8/8 ', between the paper web 1 inserted as a sheet-like shaped body and the plastic film 2 covered with the metal layer 3, polyethylene 11 is extruded from the slot nozzle.
  • the laminate of paper web 1, polyethylene 11, metal layer 3 and plastic film 2 formed at the roll station 8/8 ' is then passed on to the roll station 9/9' and there the plastic film 2 is separated for reuse, the rolls 9/9 'are preferably cooled .
  • the paper web 1 coated with polyethylene 11 and metal layer 3 is wound up on a winding station, not shown, or is fed straight to a further processing station.

Landscapes

  • Laminated Bodies (AREA)
  • Extrusion Moulding Of Plastics Or The Like (AREA)

Claims (15)

1. Procédé de métallisation par transfert, dans lequel on dépose une couche métallique sur un agent de transfert (2), et on la transfert à partir de celui- ci par stratification (6, 6') suivie de déstratification (7, 7') sur un corps de fabrication, dans lequel on met en oeuvre comme agent de transfert (2) des feuilles de polypropylène ou polyester thermofixées et orientées biaxialement par étirage, on munit la feuille de polyester avant son utilisation d'un vernis facilement détachable, on dépose un milieu liquide fondu à chaud (4) entre la couche métallique (3) de l'agent de transfert et la surface du corps de fabrication (I) prévue pour le revêtement, puis on réunit par stratification le corps de fabrication (I) et l'agent de transfert (2) muni de la couche métallique (3), et dans lequel on retire ensuite l'agent de transfert (2) du stratifié (1, 3, 4).
2. Procédé selon la revendication 1, caractérisé en ce que l'on emploie comme métal l'or, l'argent, le cuivre, le nickel, l'étain, l'aluminium ou des mélanges ou alliages d'au moins un de ces métaux, de préférence l'aluminium.
3. Procédé selon la revendication 1 ou 2, caractérisé en ce que la couche métallique possède une épaisseur comprise entre 10 et 200 nm, de préférence 10 à 100 nm.
4. Procédé selon l'une quelconque des revendications 1 à 3, caractérisé en ce que l'on emploie comme corps de fabrication des corps de formage de forme plate, en particulier ceux sous forme de bandes, de feuilles ou de plaques et qui possèdent une surface lisse ou rugueuse.
5. Procédé selon la revendication 4, caractérisé en ce que les matériaux pouvant constituer les corps de formage sont choisis dans le groupe comprenant le papier, le carton, le bois, le cuir, le caoutchouc et les matières synthétiques.
6. Procédé selon l'une quelconque des revendications 1 à 5, caractérisé en ce que l'on utilise comme milieu liquide fondu à chaud des colles fondues à chaud que l'on dépose à l'état liquide à des températures élevées se situant dans la gamme de 70 à 200°C, soit sur la surface du corps de fabrication prévue pour le revêtement métallique ou sur la couche métallique de l'agent de transfert ou sur les deux.
7. Procédé selon la revendication 6, caractérisé en ce que l'épaisseur de la couche d'enduction avec la colle fondue se situe dans la plage de 5 à 30 wm, de préférence 15 à 30 pm.
8. Procédé selon l'une quelconque des revendications 1 à 5, caractérisé en ce que l'on utilise comme milieu liquide fondu à chaud du polyéthylène, que l'on plastifie dans une extrudeuse et que l'on soumet à une extrusion en sandwich à travers une filière à fente exactement dans la fente qui se forme lors de l'assemblage de la surface du corps de fabrication prévue pour le revêtement métallique et la couche métallique de l'agent de transfert.
9. Procédé selon la revendication 8, caractérisé en ce que l'on soumet à une extrusion en sandwich le polyéthylène sous une épaisseur de couche dans la plage de 5 à 30 !lm, de préférence de 15 à 30 !lm.
10. Procédé selon l'une des revendications 1 à 9, caractérisé en ce que l'on réalise la stratification du corps de fabrication prévu pour le revêtement, en particulier du corps de formage de forme plate en bande, avec la feuille de transfert portant la couche métallique par assemblage des bandes au moyen de rouleaux, de préférence à température élevée.
11. Procédé selon la revendication 10, caractérisé en ce que les températures mises en oeuvre lors de la stratification se situent dans la plage de 80 à 200°C.
12. Procédé selon l'une des revendications 1 à 11, caractérisé en ce qu'après la stratification on refroidit le stratifié formé par le corps de fabrication, le milieu liquide fondu, la couche métallique et la feuille de transfert.
13. Procédé selon la revendication 12, caractérisé en ce que l'on refroidit le stratifié jusqu'à ce que le milieu liquide fondu se solidifie et présente une 'température de préférence en-dessous de 60°C.
14. Procédé selon la revendication 12 ou 13, caractérisé en ce que le refroidissement est effectué par insufflation d'air froid ou au moyen de rouleaux refroidisseurs traversés par un agent de refroidissement, de préférence au moyen d'une combinaison des deux méthodes.
15. Procédé selon l'une des revendications 1 à 14, caractérisé en ce que, immédiatement après le refroidissement, l'on retire la feuille de transfert du stratifié formé par le corps de fabrication, le milieu fondu à chaud qui s'est entretemps solidifié, la couche métallique et la feuille de transfert.
EP86109038A 1985-07-10 1986-07-02 Procédé de métallisation par transfert Revoked EP0208257B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3524571 1985-07-10
DE19853524571 DE3524571A1 (de) 1985-07-10 1985-07-10 Transfermetallisierungsverfahren

Publications (3)

Publication Number Publication Date
EP0208257A2 EP0208257A2 (fr) 1987-01-14
EP0208257A3 EP0208257A3 (en) 1987-12-23
EP0208257B1 true EP0208257B1 (fr) 1990-06-13

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ID=6275374

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Application Number Title Priority Date Filing Date
EP86109038A Revoked EP0208257B1 (fr) 1985-07-10 1986-07-02 Procédé de métallisation par transfert

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EP (1) EP0208257B1 (fr)
JP (1) JPS6213340A (fr)
DE (2) DE3524571A1 (fr)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4203208A1 (de) * 1992-02-05 1993-08-12 Hoechst Ag Beschichtungsmittel fuer kunststoffolien
DE4320141A1 (de) * 1993-06-17 1994-12-22 Iduso Gmbh Vierlagige Verbundfolie mit dem Aufbau Papier-Silikon-Kunststoff-Metall
FR2736649B1 (fr) * 1995-07-10 1997-10-10 Bordage Michel Procede et dispositif pour fixer au moins une matiere sur une base, notamment souple, telle que tissu ou cuir, et objet ainsi obtenu
FR2899513B1 (fr) * 2006-04-10 2012-05-11 Textiles Plastiques Chomarat Procede de fabrication d'un complexe incluant une couche de support presentant une texture specifique

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2015623A1 (en) * 1969-04-28 1970-11-12 Pfeifer, Charles F,, New Cannan, Conn, (V.Sf.A.) Binding and detaching a surface-material to/ - from a substrate molten binder
FR2258954A1 (en) * 1974-01-24 1975-08-22 Ato Emballage Div Polypapier S Metallisation of thin flexible papers, sheets or fabrics - by transfer from metallised film to a melt adhesive coating
WO1983001418A1 (fr) * 1981-10-21 1983-04-28 Dennison Mfg Co Metallisation d'organes de support
US4490409A (en) * 1982-09-07 1984-12-25 Energy Sciences, Inc. Process and apparatus for decorating the surfaces of electron irradiation cured coatings on radiation-sensitive substrates

Also Published As

Publication number Publication date
DE3671863D1 (de) 1990-07-19
JPS6213340A (ja) 1987-01-22
DE3524571A1 (de) 1987-01-15
EP0208257A2 (fr) 1987-01-14
EP0208257A3 (en) 1987-12-23

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