Adhesive bonding and miscellaneous chemical manufacture – Methods – Surface bonding and/or assembly therefor
Patent
1991-06-24
1993-08-24
Heitbrink, Jill L.
Adhesive bonding and miscellaneous chemical manufacture
Methods
Surface bonding and/or assembly therefor
156233, 156235, B29C 5900, G03H 102
Patent
active
052385167
DESCRIPTION:
BRIEF SUMMARY
The invention relates to a method for producing a material embodying an interference pattern, for example a holographic image, in which the interference pattern is introduced into a transparent layer situated on a plastic base film, a substrate being applied onto the opposite side of the transparent layer and the plastic base film being removed. Such method is known from U.S. Pat. No. 4,758,296. According to said patent, a resin layer containing a diffractive pattern is covered with a polyester film. In order to make a transfer film (i.e., a hot-stamping foil) said polyester film is treated for moderate adhesion to the resin layer, so that the resin layer will remain attached until it is later adhered to another surface.
The moderate adhesion of the polyester film to the resin layer is obtained by applying a separate release layer on the plastic base film and subsequently applying the resin layer on the release layer.
This known method is beset by a number of disadvantages. As the first disadvantage, mention is made of the fairly high costs associated with this method. All these stem from the fairly large number of layers which have to be applied to one another. The finished product, for example a sheet printed with holographic images, is consequently expensive. This method is therefore less suitable for producing wide strips of sheet-type material such as, for example, luxury packaging paper.
The object of the invention is to provide a method which is less expensive. This is achieved by applying a liquid lacquer containing a plasticizer and having a contact angle of zero degrees with respect to the plastic base film, said lacquer being capable of forming a releasable bond with the surface of the plastic base film, to a smooth major surface of said plastic base film, forming the interference pattern in the finished lacquer layer, and stripping off the plastic base film from the lacquer layer with the substrate. A saving is now achieved by omitting the step of applying a separate release layer. Surprisingly, the lacquer layer appears to form an excellent medium for introducing a holographic image into it.
The step of applying a liquid lacquer layer having a contact angle of zero degrees with respect to the base film, which lacquer layer is capable of forming a releasable bond with the surface of the plastic base film, to a smooth major surface of said plastic base film, is in itself known form EP-B-34392. However, in said patent it is not recognized that said lacquer layer is surprisingly well fit for forming a holographic image into it.
According to a first variant of the embodiment of the method according to the invention, the plastic base film is holographically printed with the aid of a printing device, such as an impression cylinder, embodying the negative of the interference pattern and the transparent release layer is then applied to the printed side of the plastic base film in a manner such that the interference pattern is imaged in the transparent release layer. When the transparent release layer is applied to the printed side of the plastic base film, the release layer is also shaped in accordance with the holographic image.
In this variant of the embodiment, it is particularly attractive to use a plastic base film which can be used a number of times in the production process such as is described in said European Patent No. 34,392. In that case, the plastic base film has only to be printed once with a hologram, while a large number of products having a holographic image can nevertheless be obtained by transferring the holographic image on the plastic base film in all cases directly to the transparent release layer. The expensive printing device, for example an impression cylinder, is therefore saved and it is only necessary to provide it once for a good impression in the plastic base film in order to obtain a large number of holographic imprints with a correspondingly high quality.
As the second variant of the embodiment, it is also possible that the transparent release layer is applied to the pla
REFERENCES:
patent: 3882207 (1975-05-01), Hannan et al.
patent: 3922416 (1975-11-01), Ryan
patent: 4629647 (1986-12-01), Sander
patent: 4631222 (1986-12-01), Sander
patent: 4631223 (1986-12-01), Sander
patent: 4758296 (1988-07-01), McGrew
patent: 5104471 (1992-04-01), Antes et al.
van der Laan Edward J.
van Suylekom Gijsbertus
Heitbrink Jill L.
Koninklijke Emballage Industrie Van Leer B.V.
LandOfFree
Method for embossing holograms does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for embossing holograms, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for embossing holograms will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-825962