In displaying and selling packaged goods, it is generally important to apply visible markings such as product identifiers, instructional material, corporate logos, trademarks and the like to the visible portions of a container for commercial purposes such as sales promotion of the goods packaged in the container. Such visible markings are generally applied directly to the visible portions of a container by various techniques including printing, embossing, etching and the like either directly onto the side walls of the container or by attaching to the container a film or wrapper having the visible markings thereon.
Various types of printed films and methods for labeling packaged goods are used throughout the packaging industry. For example, U.S. Pat. No. 6,908,687 teaches oriented or hot-blown shrink films containing a modifier component such as a plastomer and/or metallocene catalyzed ethylene-propylene copolymer, wherein the label can be coated or metallized.
U.S. Pat. No. 5,190,609 discloses a stable pressure sensitive shrink label. The heat shrink labels are formed from a polyolefin, such as a polypropylene, and have a permanent acrylic pressure-sensitive adhesive on one side. A metallized layer and open style graphics are disclosed, wherein the graphics may be protected by varnish or a second layer of heat shrinkable polyolefin material.
U.S. Pat. No. 6,303,233 discloses an uniaxially heat-shrinkable, biaxially oriented, multilayer film having a polypropylene-containing core layer, wherein metal coatings can be deposited on the multilayer film structure without the development of any noticeable crazing of the metal upon shrinking.
U.S. Pat. No. 6,127,024 discloses a battery label having a single heat-shrinkable polymeric layer, a graphic layer composed of a printed metallized layer or an ink layer, and a UV cured, heat, electron beam, or polymerized varnish layer having geometric patterns on the two linearly extending edges that correspond to the portion of the label that extends beyond and wraps around the rims of the battery.
EP 0122495 discloses films of biaxially oriented polypropylene laminated to an olefin polymeric film. The films are used as decorative wrapping paper having a metallized surface laminated thereon.
The present invention is a metallized shrinkable label composed of a shrinkable film base with a graphic applied to at least a portion of the lower surface of the shrinkable film. The graphic of the instant label is composed of a metallic coating and a shrink-resistant coating, wherein the shrink-resistant coating is printed in a predetermined pattern with defined gaps. Some embodiments embrace the shrink-resistant coating applied on the lower surface of the metallic coating, whereas other embodiments embrace the metallic coating applied on the lower surface of the shrink-resistant coating. In further embodiments, the metallized shrinkable label contains a pigmented ink applied to at least a portion of the lower surface of the shrinkable film base or the shrink-resistant coating. Methods for producing a metallized shrinkable label of the present invention are also provided.
Using conventional methods, metallized shrink films discolor when subjected to the heat required to shrink the film onto a container or product. It has now been found that discoloration is minimized when a shrink-resistant protective coating is used in combination with a metallic coating. In particular, when the shrink-resistant protective coating is applied to the metallic coating in a predetermined pattern with defined gaps and heat is applied to shrink the film, the gaps in the pattern close to produce substantially continuous protective and metallic coating layers without pleating, folding or overlapping. Accordingly, the present invention is a metallized shrinkable label and method of manufacturing the same.
Metallized shrinkable label 10 is composed of translucent shrinkable film base 16 with graphic 18 applied on at least a portion of the lower surface of the shrinkable film base 16. A graphic is intended to include, patterns (e.g., diamonds, circles, squares, etc.), images, text, barcodes and the like which cover 1% to 100% of the total surface area of the label when applied to a container or product. Graphic 18 is composed of a metallic coating 20 combined with shrink-resistant protective coating 22 as shown in
In one embodiment, graphic 18 is created by applying metallic coating 20 to the lower surface of shrinkable film base 16 and applying shrink-resistant protective coating 22 in a predetermined pattern with defined gaps 24 onto the lower surface of metallic coating 20 (
For the purposes of the present invention, the term “upper” is used to describe the layer which would be on the outer surface of a container (e.g., tube or bottle) or product when metallized shrinkable label 10 is applied as a label. As such, the term “lower” refers to the surface which would be in contact or adjacent to the container or product.
Shrinkable film base 16 can be a single ply or multi ply material that exhibits shrinkage up to sixty percent (60%) at temperatures exceeding, e.g., one hundred forty degrees Fahrenheit (140°F. or 60° C.). Suitable materials for use as shrinkable film base 16 include, but are not limited to, the polyvinyl chloride (PVC), polystyrene, polyethylene, PETG (glycol modified PET polymer) and polyolefin families of shrink film bases which provide a wide range of physical and performance film characteristics. Film characteristics play an important role in the selection of a particular film and may differ for each type of packaging or labeling application. Thus, the particular shrinkable film base employed is readily selected by the skilled artisan based on the container or product and end use thereof.
Shrink-resistant coating 22 can be composed of any clear, printable polymer material which exhibits minimal shrinkage and protects metallic coating 20 from discoloration. In particular embodiments, shrink-resistant coating 22 has three characteristics which are distinct from the varnish-style protective coatings known in the art. In one embodiment, shrink-resistant coating 22 is surfactant-free. Generally, varnishes have surfactants as part of the formula, since the purpose of a varnish is to protect the surface and simultaneously provide a surface which will allow the package to slide through subsequent processing equipment, e.g., guide rails, conveyors, etc. The instant shrink-resistant coating lacks surfactants, however, provides a “mirror-like” smooth surface to promote flow and adhesion of other inks to be printed thereon.
In another embodiment, shrink-resistant coating 22 significantly reduces the haze value of the label. Generally, shrink sleeve films have a haze factor which negatively affects the sheen of reverse-printed reflective inks such as metallic inks. The instant shrink-resistant coating causes a significant reduction in the haze factor, hence enhancing reflective appearance and sheen of metallic coatings.
In a further embodiment, shrink-resistant coating 22 retards shrinkage of under- or over-printed metallic coatings at the selective areas at which the shrink-resistant coating is printed. Since reflective inks such as metallic inks lose luster and sheen upon shrinking, the instant shrink-resistant coating effectively retains the high sheen of the reflective ink. Accordingly, a shrink-resistant or shrink-retardant protective coating as used herein is a coating that exhibits reduced shrinkage upon exposure to the heat required to shrink a shrinkable film base. Suitable shrink-resistant coatings include solvent-based, water-based or curable coating materials including epoxies, urethanes, acrylates, acrylics, and derivatives and combinations thereof which can be printed in a predetermined pattern with gaps onto the lower surface of shrinkable film base 16 or metallic coating 20. In particular embodiments, shrink-resistant coating 22 is applied or printed in predetermined patterns (e.g., diamonds, squares, bars, crosses, etc) using conventional printing techniques such as offset, letter press, gravure, silk screen, flexography, digital or combinations thereof.
Because shrink-resistant coating 22 is printed in discrete locations, i.e., patterns with gaps, the uncoated gaps 24 of the pattern close when the film base shrinks, thereby forming a continuous or substantially continuous graphic layer on the lower surface of shrinkable film base 16. See
In some embodiments, metallic coating 20 is applied only on surfaces printed with shrink-resistant coating 22 (see
Metallic coating 20 can be any typical metal including, but not limited to, aluminum, copper, silver or chromium. Particularly suitable metallic coatings include metallic inks such as a Mirasheen™ inks and high reflective index coatings such as an aluminum coating, wherein the metal is applied by a conventional printing method or applied by a vacuum metallization and de-metallization process. Advantageously, coating a vacuum-metallized graphic area with a shrink-resistant coating protects the sheen; without such a coating, the metal crazes up and a considerable amount of sheen is lost.
In particular embodiments, metallized shrinkable label 10 further has a pigmented coating or ink 26 applied to at least a portion of the lower surface of shrinkable film base 16 (
The metallized shrinkable label of the present invention can be supplied on rolls, sheets or die-cut for use on a variety of articles of manufacture including containers (e.g., squeeze tubes, bottles, cans, and the like) for consumable or purchased goods or products such as personal care products (e.g., soaps, shampoos, make-up, insect repellents, and the like); first aid products (e.g., ointments, sunscreens, and the like); cleaners (e.g., detergents and cleaning solutions); paints; and foodstuffs (e.g., yogurt, cheese-like products, jelly, and the like). In some embodiments, the label is removable, i.e., not adhered to the surface of the container product. In other embodiments, the label is secured to the article by adhesive, e.g., between the leading end of the label and the container and by adhesive between the overlapping leading end and trailing end of the label. This method is a significant improvement in the manufacture of metallized shrinkable labels because the product label is not discolored during the application and shrinking process thereby enhancing the package appearance.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/US07/66279 | 4/10/2007 | WO | 00 | 12/12/2008 |
Number | Date | Country | |
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60744757 | Apr 2006 | US |