2.
    发明专利
    未知

    公开(公告)号:FR2718075A1

    公开(公告)日:1995-10-06

    申请号:FR9403655

    申请日:1994-03-29

    Applicant: ESSILOR INT

    Abstract: A mould for prodn. of optical lenses partic. for spectacles consists of two mould shells (10A, 10B) around which is established an annual sealing sleeve (14) defining together the required mould cavity (15). The sealing sleeve (14) is made of synthetic heat shrinkable material which by heat application is constructed over the two mould shells. Initially the sealing sleeve extends over and beyond the two shells so that where shrunk in position it is driven annularly between the shells (21) in the form of an inverted `U' so locating them axially. Also claimed are lenses formed from such a mould.

    4.
    发明专利
    未知

    公开(公告)号:FR2673576A1

    公开(公告)日:1992-09-11

    申请号:FR9102827

    申请日:1991-03-08

    Applicant: ESSILOR INT

    Abstract: This procedure is of the kind in which the absorption, by a base-polymer material, of an additive composition enclosing at least one monomer capable of leading to a polymer of different refractive index is ensured. … According to the invention, by choosing a swelling composition as the additive composition, a first preform (P1) is produced, with a first geometry (G1), from a polymer material at a rate of advance sufficient for it to be self-supporting, a confinement volume (14) is defined between this first preform and an abutment element having a second geometry (G2) corresponding to a greater volume, and it is brought into contact there with a quantity of swelling additive composition sufficient for the swelling, to which it is then subjected, to cause it to match, under stress, this second geometry (G2). … Application, especially, to the production of ophthalmic lenses. … …

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