Abstract:
Un appareil de fabrication à base de verre comprend un appareil de distribution transportant du verre fondu dans une direction de déplacement (107). L’appareil de fabrication à base de verre comprend un premier rouleau de formage (701) comprenant une poche texturée qui reçoit le verre fondu et communique une forme définie correspondante au verre fondu (103). La poche texturée comprend une première extrémité de poche, une deuxième extrémité de poche et une région de poche centrale s’étendant de manière circonférentielle entre la première extrémité de poche et la deuxième extrémité de poche. L’appareil de fabrication à base de verre comprend un moule (113) positionné pour recevoir le verre fondu comprenant la forme définie à l’intérieur d’une cavité de moule (201) du moule. Les procédés pour fabriquer du verre sont également prévus. Figure 7
Abstract:
A glass ceramic or glass-ceramic sheet is formed by progressively reducing the thickness of the sheet by passing the sheet between successive pairs of counterrotating rollers. The average viscosity of the sheet is maintained between 5x104 and 109 P during the sheet forming operation.
Abstract:
A rod of material having a cross-sectional compsn. gradient is obtd. by simultaneously passing a core stream of one compsn. and a concentric annular sheathing stream of a different compsn. into a casting tube. Appts. includes at least two reservoirs having concentric discharge orifices through which the materials flow by gravity into a concentric casting tube. A heating system controls the temp. profile of the material as it flows through the tube and provision is made for controlling the rate of flow. From its outlet the materials pass in laminar flow to a concentric mould of greater cross-section. Pref. the compsn. gradient is controlled by adjusting the flow rates and temp. at a selected interface position between core and sheath.
Abstract:
Appts. comprises a mould having a porous cylindrical internal wall through which gas is injected to create a surface film separating the glass from the mould. Also claimed are glass rods formed by casting a glassy material in a molten state in a mould; and a method of shaping glassy material into rods in the mould, the material not being in direct contact with the mould wall. Pref. the mould wall is formed from graphite, stainless steel, nickel alloy, bronze, or ceramic. Casting may proceed continuously in an open-bottomed mould below which are guide rolls that control the discharge rate of the casting.
Abstract:
Producing a sheet from a vitreous material by pressing between contra-rotating rolls to reduce at least locally the thickness of the sheet (F) to a predetermined thickness. The thickness of the sheet is reduced progressively by a sequence of successive passes through the contra-rotating rolls (1i, 2i, 3i) whilst maintaining the average viscosity of the sheet between 5.104 and 109 poise, at least before the last pass between the rolls. The sheet is reduced from its initial thickness (e) in a succession of small steps (e1 , e2 , e3 ) in order to overcome problems associated with differential shrinkage. Also claimed are (I) a device consisting of a number of pairs of contra-rotating rolls (1i, 2i, 3i), a set of conveyors (4i ) and heating systems (5I) between the pairs of rolls, and, (II) a control plate for a flat screen for displaying cathode ray images, consisting of a network of electrodes carried by a glass sheet.
Abstract:
Glass-ceramics exhibiting a Vickers indentation crack initiation threshold of at least 15 kgf are disclosed. These glass-ceramics may be ion exchangeable or ion exchanged. The glass-ceramics include a crystalline and amorphous phases generated by subjecting a thin precursor glass article to ceramming cycle having an average cooling rate in the range from about 10 °C/minute to about 25 °C/minute. In one or more embodiments, the crystalline phase may comprise at least 20 wt% of the glass-ceramics. The glass-ceramics may include β-spodumene ss as the predominant crystalline phase and may exhibit an opacity ≥ about 85% over the wavelength range of 400-700nm for an about 0.8mm thickness and colors an observer angle of 10° and a CIE illuminant F02 determined with specular reflectance included of a* between -3 and +3, b* between -6 and +6, and L* between 88 and 97.
Abstract:
According to one embodiment, a method for forming a laminated glass sheet includes forming a multi-layer glass melt (300) from a molten core glass (106) and at least one molten cladding glass (126). The multi-layer glass melt (300) has a width Wm, a melt thickness Tm and a core to cladding thickness ratio TC:TCl. The multi-layer glass melt (300) is directed onto the surface of a molten metal bath (162) contained in a float tank (160). The width Wm of the multi-layer glass melt (300) is less than the width Wf of the float tank (160) prior to the multi-layer glass melt (300) entering the float tank (160). The multilayer glass melt (300) flows over the surface of the molten metal bath (162) such that the width Wm of the multi-layer glass melt (300) increases, the melt thickness Tm decreases, and the core to cladding thickness ratio TC:TCl remains constant as the multi-layer glass melt (300) solidifies into a laminated glass sheet. The invention also relates to the associated apparatus.
Abstract:
A fusion draw apparatus includes a pair of engagement rollers. At least one of the pair of engagement rollers includes a circumferential knife edge configured to cooperate with the other of the pair of engagement rollers to thin the edge portion or sever the edge portion from a central portion of the glass ribbon within the viscous zone of the glass ribbon. In further examples, fusion draw methods include the step of thinning the edge portion or severing the edge portion from the central portion of the glass ribbon within the viscous zone.