Polishing product element, particularly for finishing optical lenses

Abstract

A polishing element of the pad type for finishing mineral or organic optical lenses. The polishing element includes a base plate on which fibers are deposited by flocking them onto the surface of the aforesaid base plate in orthogonal fashion, with the aforesaid fibers consisting of viscose and / or polyamide fibers that are affixed onto the base plate by means of an adhesive. The adhesive is based on polyurethane.

Description

RELATED APPLICATION [0001] The present application claims priority to French Application No. 03 13541 filed Nov. 19, 2003. TECHNICAL FIELD [0002] This invention concerns a polishing product element for finishing optical lenses. BACKGROUND OF THE INVENTION [0003] Optical lenses undergo several transformative steps in order to attain their required geometrical shape and final transparency. [0004] The surfacing of optical lenses, with a concave or convex face, includes at least three major steps: [0005] rough shaping, which makes it possible to attain the general profile, [0006] fine grinding, which makes it possible to smooth the surface, and [0007] polishing, which further refines the surface and imparts transparency to the lens. [0008] Taking into account the diversity of the profiles in optical lenses, specific supports, called “pads,” have been developed that can be mounted in a removable manner on rigid or non-rigid rotating supports, called “tools,” and that are used as componen...

AI Technical Summary

Benefits of technology

[0014] It is the goal of this invention to improve the performance further, especially concerning longevity, by proposing pads that can consecutively polish several optical lens surfaces without impairing the polishing quality or the duration and efficiency of each successive polishing operation performed with the pad before it is finally discarded.

[0017] In comparison with known pads, including those according to FR 2 794 390, such pads, when used on tools having a coating made of a plastic foam onto which the pads are affixed by means of an adhesive, have shown a remarkable ability to polish successively a considerably higher number of surfaces with the same pad while using a conventional polishing liquid. Thus, tests have shown that a single pad was capable of polishing about twenty or more surfaces as compared with only a few surfaces at best with a conventional pad, and this in a notably reduced time due to a considerably increased resistance of the fibers to being pulled off, resulting from the association of a base plate made of a cotton fabric with an adhesive based on polyurethane.

[0018] According to another embodiment of this invention, which is even more effective, the base plate consists of a foam, in particular of polyurethane, with the pad then being placed directly on the smooth and hard surface of a tool without its conventional flexible coating and being attached by means of an adhesive. Such a pad makes it possible to polish more than one hundred surfaces with the same efficiency as before, thus confirming the excellent resistance of the fibers to being pulled off.

[0019] The greater longevity of the pad results from the fact that the connection with the tool is much more durable thanks to the polyurethane foam base plate that provides a barrier between the polishing liquid and the adhesive, which barrier is interposed between the pad and the tool and makes it possible to profit, for a much longer time from the excellent anchorage of the fibers obtained via the polyurethane based adhesive, i.e., to polish a much higher number of surfaces with the same pad before the latter detaches from the tool, this detachment being inevitable but the time of which is pushed back thanks to this invention.

Problems solved by technology

Lenses are now mostly organic and the difficulties that arise involve not only the technical in the production of the profiles but also the manufacturing lead times for, on the one hand, production on demand within the shortest possible turnaround and, on the other hand, an increase in productivity.

Images