DE674838C - Process for producing edge protection for multilayer, shatterproof glasses - Google Patents

Description

To protect many products made of multilayer safety glass, especially those with an intermediate layer of cellulose derivatives, processes have long been used which provide an airtight seal for the intermediate layer from the effects of the weather, in particular from moisture. By applying all kinds of paint to the Edge of the glass, e.g. B. by paint, asphalt, pitch and similar substances, by filling in the Edge of the glasses between these with putty, pitch, etc., an effective edge protection was sought to achieve. It has also been suggested by spraying or dusting one liquid metal layer to achieve a seal on the edges of the glass composite.

The previous procedures were associated with a lot of work and relatively high costs. Attempts have also been made while combining the elastic intermediate layer with the covering glass panes on the outer edge of the elastic intermediate layer a corresponding Insert metal ring. Similar measures which, however, only have a mechanical task, namely to hold two panes of glass together, have been described many times been. For example, the cohesion of panes of glass separated by a space, where partly air, partly a transparent, elastic material the gap fills, done by applying an annular seal over the edges of the glass composite protrudes. Even on optical rimless lenses, the lens edge is enameled afterwards to avoid light reflections is branded, provided. Furthermore, for the production of fog-free gas mask glasses, in which the moisture is absorbed by water-absorbing substances such as gelatine or the like lying on the inside of the gas masks, is tied, the attachment of an elastic bandage, e.g. B. made of rubber, proposed but which only mechanically holds the glass together, without a

To achieve sealing to the outside.

The method according to the invention aims at a substantial simplification of the edge sealing of multilayer glass by using foils made of organic thermoplastics, such as cell horn, cellulose derivatives, or from condensation products, polymers or Similar materials are used, these foils are placed around ίο the edge to be protected without closing it overlap, and firmly connects with this. This can either be done with an adhesive, with which one glued the foils with the edge, or the foils can also be solved by solution or Swelling agent made gluable, heated or by applying weak pressure to the area to be protected Glass edge can be placed and fastened with it. Of course, any of the above can be used or similar measures can also be applied collectively. Instead of foil strips you also take closed foil rings, which then z. B-. more rounded or oval over the edge Glasses are pulled after the rings have been stretched a little in the heat, for example. When they cool down, they contract again and lie firmly around the edge of the glass, the seal them airtight. Also by gluing, be it by an adhesive or by swelling desFölienringes or the like, the same result can be achieved.

The foil or the foil ring can be colorless, transparent, colored, with an inscription or otherwise be provided with ornaments or the like.

The thickness of the film or the film ring can be between 0.1 mm and below, but also up to several millimeters. The height of the foil or the foil ring can be exactly that Thickness of the glass to be protected, but it can also be less, as well as it it is also possible that they are slightly over the edge of the glass protrudes. The latter type has the advantage that when clamping glasses in Frames, the pressure does not act directly on the glass, but on the edge protection, which Safety glass is therefore protected from shattering when the socket is tightened. The solution this task has been attempted earlier by creating a step-like composite, :> o in which the disc with the larger diameter carries the elastic intermediate layer, which acts as a seal acts against the edge of the socket.

In general, it will be sufficient if the glasses have cut edges, in certain cases however, it may be desirable to have the edge processed before or after the edge sealing to undertake.

-In most cases, that will be enough the edge protection creates a simple flat edge. But it can also under certain circumstances it may be desirable to have the edge in the form of a profile, e.g. B. a bulge or a facet, to train, as is often the case with spectacle lenses that are used in relatively narrow frames must be, is necessary. Previously this had to be done by grinding a facet of Hand or by means of a faceting machine.

The invention makes it possible to bypass the grinding by having the Provides the edge strip or ring with a corresponding facet profile, i.e. not the ring as a flat, rather than a profiled band. This is achieved in a single operation an edge sealing and faceting, which are otherwise associated with quite substantial costs is.

As tests have shown, the edge protection according to the invention is an excellent one Protection against the ingress of moisture. Multilayer eyeglass lenses applied to the are provided with edge protection in the manner described, can be left in the boiling state for several hours Water lie without any significant change in the intermediate layer at the edges would have occurred.

The method described is not only suitable for spectacle lenses, but can also be used for all forms and uses of safety glass can be used. For more complicated ones and larger slices, however, will primarily use open ones Foil tapes and not closed rings are more advisable.

Claims (1)

Claim: Method of making edge protection for multilayer shatterproof Glasses, in particular for spectacle glasses made of safety glass, characterized in that smooth or shaped bands or rings made from organic thermoplastics placed around the edge of the glass to be protected without overlapping it be attached to this.