Abstract:
In the coloring of bodies of glass by diffusion of coloring ions from a treatment medium into surface layers thereof, the repeatability of the resulting coloration is improved by controlling not only the treatment temperature and composition of the medium and the treatment time, but also by controlling the electrical potential within the medium between a pair of electrodes in contact therewith. Preferably, for electrodes of specified composition and structure, this potential is maintained at a value between -600 mV and +300 mV.
Abstract:
Bodies made of soda-lime-silica glass of ordinary composition and containing a small concentration of reducing ions at least in surface layers thereof and having no visible coloration are given a yellow coloration by diffusing a substance into such surface layers from a contacting medium which is composed of a mixture of metal salts containing between 0.01% and 3% by weight of a silver salt furnishing reducible silver metal ions capable of being reduced by the reducing ions in the glass in such a manner as to give the glass a yellow coloration. The diffusion step is conducted under concentration, temperature and time conditions which do not give a significant visible coloration to the glass. Subsequent to the diffusion, the glass bodies are heat-treated at a temperature above the strain point of the glass to develop a yellow coloration.
Abstract:
A method for modifying the radiation-transmitting properties of an article composed of at least one sheet having a substantial degree of transparency to radiation and at least one layer or sheet disposed adjacent the at least one sheet and forming a screen which serves to impart to the article as a whole a reduced degree of transparency to such radiation, the method involving reducing the transparency-attenuating effect of the screen in at least one zone of the article so as to give the article different transparencies at different zones thereof. Articles having a certain degree of transparency to radiation and having different degrees of transparency at different zones thereof.
Abstract:
Method and apparatus for chemically treating glass, e.g., chemical tempering, wherein different areas of the glass are subjected to different treatment. For example, certain areas may be subjected to a stronger treatment than others to provide different areas of the glass with different characteristics.
Abstract:
An article containing at least one glass sheet which has been chemically tempered to create tensile stresses in an internal zone thereof and compressive stresses in external layers thereof, the chemical tempering being carried out in such a manner that, for at least a portion of the sheets, the arithmetic product of the thickness of such internal zone and of the maximum tensile stress in such zone is within a given range of values for which the sheet will fracture into large fragments under the impact of a small projectile and will fracture into small noncutting fragments under an impact of a large body approximating a human being.
Abstract:
A method and apparatus for producing sheet glass drawn from a molten glass bath in a drawing kiln in which a forward current of hot glass flows upon a return current of cooler glass flowing in the opposite direction by intercepting a portion of the forward current at a point directly downstream of the point where the glass is drawn from the bath for causing only glass from the intercepted portion of the forward current to be drawn.
Abstract:
A procedure for forming curved, tempered glass sheets by chemically tempering the sheets by means of a diffusion process and then bending the sheets to the desired curved form while the sheets are at a raised temperature which gives them a viscosity of no less the 10**10 poises, whereby the sheets can be bent after tempering without having to be subjected to extremely high temperatures.