Method and apparatus for manufacturing pressure sensitive adhesive label stocks with printing under adhesive and product produced thereby

Abstract

A method and apparatus for making adhesive-backed labels. Glassine paper stock is unwound from a roll, coated with photo-cationic silicone and exposed to wavelength-controlled illumination to cure. Hot melt adhesive is applied over the silicone. Simultaneously, label stock is fed with the coated glassine paper to laminating rollers where the two are joined. Illumination is provided by a dichroic reflector.

Description

FIELD OF THE INVENTION AND CROSS-REFERENCE TO RELATED APPLICATION [0001] This invention relates to self-adhesive labels and the like and, more particularly, to a method and apparatus for efficiently manufacturing pressure sensitive self-adhesive label stock in such a way as to allow printing on the adhesive side. This application is a divisional of U.S. Ser. No. 10 / 210,212, filed Aug. 1, 2002, and claims priority thereto.BACKGROUND OF THE INVENTION [0002] It is known in the art to apply printed adhesive-backed labels to containers for products such as liquid soap and detergent, shampoo, food products and vitamins to name only a few. Self-adhesive labels are generally made in such a way as to require the removal of a “release paper” from the adhesive side of the label before it is applied to the container. Removal of the release paper exposes the pressure sensitive adhesive, permitting the label to be applied to the container. Slight pressure is then applied to create the adhesive bo...

AI Technical Summary

Benefits of technology

[0011] According to a first aspect of the present invention, a method for manufacturing pressure sensitive adhesive labels or label stock is provided, which method is simpler and more expeditious to carry out than the prior art manufacturing method described above. In particular, the method of the present invention eliminates the need for multiple lamination passes, long curing times and the associated de-reeling and re-reeling or re-winding steps described above.

[0014] One of the numerous advantages which obtains from the inventive method is the ability to preprint on the reverse side of the face stock before the adhesive is applied thereby to eliminate the need for subsequently de-laminating the pressure sensitive adhesive label stock at a point downstream in the overall manufacturing process. Moreover the preprinted label stock is laminated with the adhesive after printing, thus eliminating the likelihood for blurred printing on the reverse side of the label stock.

Problems solved by technology

The adhesive which constitutes a layer between the face stock and the silicone is typically water based and, therefore, requires relatively long air drying time.

Secondly, the prior art method described above requires numerous de-reeling and re-reeling or re-winding steps and multiple lamination steps.

Thirdly, the prior art method described above makes it particularly difficult to print on the reverse side of the label stock; i.e., the side to which the adhesive is relatively strongly bonded.

This gives rise to blurry, less definite printing and typically requires protection of the printed adhesive through the addition of, for example, UV varnish or UV glued film.

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