The present application is related to a co-assigned and co-filed United States patent application entitled Microembosser for Faster Production of Holographic Labels. This related application is incorporated herein by reference.
The present invention concerns microembossing, printing, laminating, and diecutting technologies, especially as used in the manufacture of holographic labels or stickers.
Microembossing is a process of imprinting or cutting microscopic grooves into a layer of material, sometimes called a substrate. One use of microembossing is to emboss a hologramxe2x80x94a three-dimensional image of an objectxe2x80x94on a paper-thin substrate of reflective plastic. The embossed substrate can then be used as part of a holographic label.
Holographic labels are used on a variety of articles of manufacture for security, authenticity, or aesthetic appeal. For example, holographic labels are used on compact discs, computer software, cosmetics, watches, and sporting goods. Other uses include clothing hang tags, automobile-registration certificates, fine-jewelry certificates, concert and sporting-event tickets, recreational passes, credit cards, passports, driver licenses, postage stamps, government bonds and certificates, and so forth.
Producing holographic labels or stickers generally entails a multi-pass process, which begins with forming a specific diffractive pattern, for example, a five-by-five array of 25 three-dimensional bald eagle images, on a thin rectangular sheet of metal known as a stamping shim. Using the stamping shim like a printing plate, a microembosser repeatedly imprints or embosses the array of bald eagles onto a long section of metalized polyester film, called a web. The embossed film is then typically rolled and loaded into a separate laminating machine, which laminates, or glues, a pressure-sensitive adhesive material to the back of the web, forming the peel-away part of each sticker.
The laminated web is then rolled and loaded onto a printer, which prints images at designated positions on the web. For example, one could print a ring of white stars around each of the 25 embossed eagle images, using a printing plate which includes a corresponding five-by-five array of 25 star rings. To ensure proper registration, or alignment, of the array of star rings with the array of eagle images, some printers include special controls that adjust relative position of the printing plate and the web during printing. However, these controls generally limit printing speed and waste some of the web, which is rolled up as it exits the printer.
The manufacturing process then continues by loading the rolled web of embossed and printed images onto a separate, stand-alone diecutter which cuts each star-encircled eagle image from the web to form a sticker of a certain shape. The diecutter typically includes a die cylinder (or steel-rule die) with a specific pattern of raised cutting edges on its surface. For example, the die cylinder could include a five-by-five array of 25 square-shaped cutting edges that corresponds to the array of star-encircled eagles on the web. In operation, the die cylinder rolls over the web of star-encircled eagle images, cutting out each image as a separate square-shaped sticker. To ensure registration of the array of square-shaped cutting edges with the array of star-encircled eagles, it is often necessary to stop diecutting to manually adjust position of the die cylinder or the web.
One problem with this process is its use of separate, stand-alone machines for embossing, laminating, printing, and diecutting. This means that the web must be unrolled, rerolled, and transferred from one machine to the next, ultimately slowing the manufacturing process. Moreover, the web stretches and contracts during and after each stage of manufacture, often requiring adjustments to correct registration of embossed, printed, and/or diecut patternsxe2x80x94a procedure which further slows the manufacturing process. Accordingly, there is a need for a better way of making holographic stickers and labels.
To address this and other needs, the inventors have developed an in-line rotary microembosser for use with a rotary laminator, printer, and/or diecutter. One embodiment, or implementation, of the invention includes a rotary microembosser operatively coupled in line with a rotary laminator, a rotary printer, a rotary diecutter, or another web processing device to concurrently process a continuous web. This exemplary arrangement not only eliminates one or more of the machine-transfer and machine-loading delays which occur when using a separate embosser, laminator, printer, and diecutter, but also reduces the need to correct registration errors at each separate machine. Accordingly, this and various other embodiments of the invention reduce the time required to manufacture products, such as holographic labels.