| 摘要 |
<p>The invention relates to a molded part made of a thermoplastic elastomer material, more particularly a homopolymer charged with polypropylene and rubber having extremely low hardness. Said part can be used as a label, publicity support or the like. The inventive part is very thin and generally flat and has a smooth face while the opposite face has a raised perimetrical strip (that may or be not be subdivided into individual projections). The inner part of said strip has a central surface portion, which is depressed relative to the above-mentioned strip, said central portion being intended for receiving a corresponding ornamentation serving as a labeling (silk screening, pad printing, etc.) or laminar accessory (sticker or the like) while preserving the antislip properties of said part. The part is produced by submarine gate molding, without the use of a toggle lever, cold casting, that makes it possible to mold the part while avoiding that the physical properties of the material, particularly its highly anisotropic character, could result in structural defects that would make it impossible to correctly apply the above-mentioned surface ornamentation or cause deterioration of the latter once it has been applied. The production method involves the following steps: closing the press of the injection machine; introducing the thermoplastic material with the desired dying material into the screw device; heating the cylinder of the screw device until the material that has been introduced melts; turning the screw device at a high speed with a low counter-pressure; allowing the material that has been introduced into the press to cool off; opening the press and the molds located therein and actuating the ejectors that are provided with rotating rollers in combination with means driving the bottom of the impression to 'sweep' the parts until they are dragged out of the press; and ejecting the cold casts.</p> |
