The release carriers of the prior art are made by applying a polyolefin, preferably polypropylene, onto a continuous sheet of release paper, passing the polypropylene covered paper around a chill roll and rolling the release carrier onto a core for further processing, storage, shipment and handling. Since the polypropylene is set while in contact with the chill roll, it takes on the inverted image of the roll. Therefore, it is critical that the surface of the chill roll be defect free.
Even if the chill roll is maintained defect free, dull streaks are created in the release carrier due to gauge bands (the difference in caliber or thickness) of the release paper in the machine direction. It is common for 3,000 laps of release carrier to be wound into a 42 inch diameter roll. Due to the cumulative effect of the gauge bands, the difference in diameter across the roll is typically as much as 1/4 inch. This leads to rubbing of the backside of the release paper against the adjacent polypropylene surface causing dull streaks in the high gloss polypropylene surface during handling and storage.
Presently, the surface defects are removed during manufacture of surface coverings such as vinyl floor coverings by pretreating the release carrier at the floor covering manufacturing site. As the release carrier is unrolled, the polypropylene is heated to a temperature greater than its melting point (in excess of 350.degree. F.) and planished. While the dull streaks are removed by this process, the planisher must be maintained defect free.
Further, no known prior art release carrier has been made having two different predetermined gloss levels in predetermined areas of the release carrier.
Davidson, U.S. Pat. No. 3,507,733, discloses the use of a polypropylene coated release carrier in the manufacture of an embossed decorative surface covering.
Erb et al., U.S. Pat. No. 3,773,545, discloses a process for controlling the surface gloss of a vinyl coated floor covering. In particular, they disclosed the use of a hot polishing roll on a cool vinyl coated substrate to improve the gloss.
O'Sullivan, U.S. Pat. No. 4,478,663, discloses the use of a highly polished chill roll which has depressions of an average depth of about 5 microns and an average area for each depression of less than 16,000 square microns.
As evidenced by O'Sullivan, the teachings of the present invention can also be applied to products composed of laminates of plastics and other materials used in a variety of packages and containers such as plastic bags.