Classifications

• • C—CHEMISTRY; METALLURGY
  • C03—GLASS; MINERAL OR SLAG WOOL
  • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
  • C03B23/00—Re-forming shaped glass
  • C03B23/02—Re-forming glass sheets
  • C03B23/023—Re-forming glass sheets by bending
  • C03B23/0235—Re-forming glass sheets by bending involving applying local or additional heating, cooling or insulating means
• • C—CHEMISTRY; METALLURGY
  • C03—GLASS; MINERAL OR SLAG WOOL
  • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
  • C03B23/00—Re-forming shaped glass
  • C03B23/02—Re-forming glass sheets
  • C03B23/023—Re-forming glass sheets by bending
  • C03B23/025—Re-forming glass sheets by bending by gravity
  • C03B23/0256—Gravity bending accelerated by applying mechanical forces, e.g. inertia, weights or local forces
• • C—CHEMISTRY; METALLURGY
  • C03—GLASS; MINERAL OR SLAG WOOL
  • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
  • C03B23/00—Re-forming shaped glass
  • C03B23/02—Re-forming glass sheets
  • C03B23/023—Re-forming glass sheets by bending
  • C03B23/025—Re-forming glass sheets by bending by gravity
  • C03B23/0258—Gravity bending involving applying local or additional heating, cooling or insulating means
• • C—CHEMISTRY; METALLURGY
  • C03—GLASS; MINERAL OR SLAG WOOL
  • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
  • C03B23/00—Re-forming shaped glass
  • C03B23/02—Re-forming glass sheets
  • C03B23/023—Re-forming glass sheets by bending
  • C03B23/03—Re-forming glass sheets by bending by press-bending between shaping moulds
  • C03B23/0305—Press-bending accelerated by applying mechanical forces, e.g. inertia, weights or local forces
• • C—CHEMISTRY; METALLURGY
  • C03—GLASS; MINERAL OR SLAG WOOL
  • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
  • C03B23/00—Re-forming shaped glass
  • C03B23/02—Re-forming glass sheets
  • C03B23/023—Re-forming glass sheets by bending
  • C03B23/03—Re-forming glass sheets by bending by press-bending between shaping moulds
  • C03B23/0307—Press-bending involving applying local or additional heating, cooling or insulating means
• • C—CHEMISTRY; METALLURGY
  • C03—GLASS; MINERAL OR SLAG WOOL
  • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
  • C03B23/00—Re-forming shaped glass
  • C03B23/02—Re-forming glass sheets
  • C03B23/023—Re-forming glass sheets by bending
  • C03B23/035—Re-forming glass sheets by bending using a gas cushion or by changing gas pressure, e.g. by applying vacuum or blowing for supporting the glass while bending
  • C03B23/0352—Re-forming glass sheets by bending using a gas cushion or by changing gas pressure, e.g. by applying vacuum or blowing for supporting the glass while bending by suction or blowing out for providing the deformation force to bend the glass sheet
  • C03B23/0355—Re-forming glass sheets by bending using a gas cushion or by changing gas pressure, e.g. by applying vacuum or blowing for supporting the glass while bending by suction or blowing out for providing the deformation force to bend the glass sheet by blowing without suction directly on the glass sheet
• • C—CHEMISTRY; METALLURGY
  • C03—GLASS; MINERAL OR SLAG WOOL
  • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
  • C03B23/00—Re-forming shaped glass
  • C03B23/02—Re-forming glass sheets
  • C03B23/023—Re-forming glass sheets by bending
  • C03B23/035—Re-forming glass sheets by bending using a gas cushion or by changing gas pressure, e.g. by applying vacuum or blowing for supporting the glass while bending
  • C03B23/0352—Re-forming glass sheets by bending using a gas cushion or by changing gas pressure, e.g. by applying vacuum or blowing for supporting the glass while bending by suction or blowing out for providing the deformation force to bend the glass sheet
  • C03B23/0357—Re-forming glass sheets by bending using a gas cushion or by changing gas pressure, e.g. by applying vacuum or blowing for supporting the glass while bending by suction or blowing out for providing the deformation force to bend the glass sheet by suction without blowing, e.g. with vacuum or by venturi effect

Definitions

• the invention relates to a method for the production of a molded glass article with a predetermined geometry, the use of a
• the document US 2010/0000259 A1 essentially describes the bending of glasses with the preferential use of medium-wave IR radiation, which is preferably absorbed in the glass.
• WO 2011/000012 A1 describes a laser-heated bending press of materials.
• A area to be lowered in m 2 ;
• d thickness of the glass in m
• I length of the heated line in m.
• Viscosity determines the rate of deformation and need only be sufficiently low to ensure deformation in finite time.
• WO 2005/042420 A1 discloses a method for producing a glass molded part with polygonal plate-shaped and optionally at least partially bulged base surface and at least one limb bent along an edge of the base surface with the following steps:
• Peripheral area of the glass plate is heated to a temperature that larger than that of the central portion of the glass plate, so that the latter is deformed on the Formpatrize by its own weight.
• the thus deformed glass plate is pressed by a molding die whose dimensions correspond to the outer dimensions of the glass product.
• WO 20/055587 A1 likewise discloses a method for deforming a flat glass.
• the object of the invention is to find a method for the shape-free production of a molded glass article with a predetermined geometry, which overcomes the disadvantages of the prior art described. Furthermore, it is an object of the invention to produce molded glass articles with high surface quality inexpensive and easy and in particular to avoid post-processing steps.
• the object is achieved according to claim 1 by a method for the shape-free production of a molded glass article having a predetermined geometry, wherein the method has at least the following steps:
• Starting glass is maintained, is not exceeded by 10 13 dPas, wherein the heating by means of at least one laser beam along a closed line, and
• the object is achieved according to claim 19 by a molded glass article obtained from a starting glass, which has at least one reduction T for which applies
• A surface of the starting glass to be lowered in m
• ⁇ surface tension of the heated starting glass N / m
• the surface of the molded glass article after deformation has no impurities of greater than 1 pm, in particular greater than 0.1 pm.
• A, d, p, B, ⁇ and I can be measured on the shaped glass article (see also Figure 6).
• impurities are meant essentially surface defects that may be caused by mold contact.
• form-free according to the invention means in particular that the heated part does not come into contact with a mold.
• the starting glass used is a flat glass which is shaped by means of the method according to the invention to obtain a shaped glass article.
• a soda-lime glass, a borosilicate glass or an aluminosilicate glass is preferably used as the starting glass.
• the starting glass is preheated.
• the preheating is preferably carried out in a separate oven.
• heating parameters in particular the viscosity to be maintained of the starting glass in the partial region
• deformation parameters in particular the deformation time and deformation force
• the heating of the subarea is effected by means of at least one burner or by means of IR radiation.
• the sub-area is particularly preferably scanned with a frequency of the laser beam of at least 2 Hz.
• the entire subarea can be heated simultaneously or in a chronological order.
• the heating is along a closed line.
• the heating can be carried out in such a way that a predetermined thermal gradient is set between the partial region and the remaining regions of the starting glass.
• the heat card is preferably used by means of suitable measuring methods
• thermal image sensor measured and / or is the Deformation by means of suitable measuring methods, in particular by means of optical sensors and / or acoustic sensors, measured.
• the additional force can act in particular on the heated starting glass by applying overpressure and / or underpressure.
• the further force can be exerted by a pressure gradient over the starting glass.
• the further force can also be transmitted via a mechanical punch, which preferably acts on locations of the glass plate which are at high viscosity.
• the resulting glass article preferably has no impurities (pits) with a dimension of greater than 1 ⁇ m, in particular greater than 0.1 ⁇ m.
• the glass article obtained has a half-shell-shaped
• TemperaturA / iskosticiansverlaufes can also represent other geometries. In particular, those which have sections already lowered over the plane of the original glass pane.
• the glass article produced by the method according to the invention can be used for electronic devices, in particular as part of a housing or a screen.
• FIG. 1 shows a flowchart with preferred method steps.
• Figure 2 shows the production of a recess in a flat glass, which is kept outside during the deformation and a novel invention
• FIG. 3 shows the lowering of an area in a flat glass, which is kept outside during the deformation, as well as a section according to the invention
• Figure 4. shows the lowering of the edge region of a flat glass, which is held inside during the deformation and a novel invention
• FIG. 5 shows the shaping of a flat dome in a flat glass and a glass article according to the invention. Top in top view and bottom along the
• FIG. 1 shows an exemplary flowchart with preferred
• Temperature (viscosity) - time-course can be achieved.
• the force is adjusted via the size of the pressure gradient across the glass.
• the starting glass flat glass
• the starting glass flat glass
• FIG. 2 shows the production of a depression in an aluminosilicate flat glass (deformed flat glass 1), which was kept outside during the deformation.
• the heating of a starting glass was carried out in the partial area 2 to a temperature such that a viscosity of 10 7 to 10 13 dPas was obtained in this partial area, and in the partial area 3 to a temperature such that a viscosity of 10 4 in this partial area until 10 8 dPas was obtained.
• the heating was carried out in such a way that a viscosity of the starting glass was not fallen below 10 13 dPas at the points at which the starting glass was held.
• the thus heated starting glass was through
• FIG. 3 shows the production of an asymmetrical recess in a flat glass (deformed flat glass 1), which was kept outside during the deformation.
• the heating of a starting glass (flat glass) took place in the subregions 2, 3, 4, 5 and 6 to different temperatures, so that different viscosities were obtained in these subregions.
• Heating was carried out in such a way that a viscosity of the starting glass was not fallen below 10 13 dPas at the points at which the starting glass was held. The thus heated starting glass was through
• FIG. 4 shows the deformation of the edge region of a flat glass which was held inside during the deformation.
• the deformation was controlled purely by the time-viscosity-force exposure, that is, there was no two-dimensional form contact, so that no expensive forms accrue.
• a flat glass (starting glass) was at least partially brought to a temperature which corresponded to a viscosity of 10 13 dPas.
• the flat glass was held in an area that should not be deformed. In this area, the glass remained at a viscosity> 10 13 dPas, so that no damage to the glass surface could result from the support. In some areas, the viscosity has now been lowered so much that "sagging" or subsidence of partial areas of the flat glass has occurred, the minimum viscosity values being in the range of 10 8 dPas or even 10 5 dPas, depending on the thickness of the glass and desired
• the time-viscosity-force curve was chosen so that the deformation came to a standstill at a time when the desired shape or a desired intermediate shape was achieved.
• Starting glass penetrate different depths and thus act in different depths of the starting glass.
• other sources of heat were also used, especially when a small amount of deformation was desired that required a low viscosity gradient.
• a planar thermal image sensor was used.
• sensors can also be used which detect the position of the deformed glass. In one embodiment, these sensors were used to determine the final geometry. In another embodiment, these sensors were used to control the process. In particular, ultrasonic sensors and / or optical
• the flat glass to be formed was taken up by a frame, so that portions could deform inside the flat glass.
• the flat glass can also be supported centrally, so that the edges can be deformed. In any case, the bearing surface was so
• the corresponding bending point can then, depending on the lever length, be adjusted to an average viscosity, eg in the range 0 9 dPas to 10 8 dPas.
• Figure 5 shows, for example, the production of a flat dome in a flat glass 1, e.g. the guidance of the finger can serve for a touch-sensitive screen (touch screen). The heating took place here in subarea 3.
• the glasses thus formed were preferably used in mobile or non-mobile electronic devices as cover glasses (cover glasses).
• cover glasses cover glasses.
• Table shows surface properties of glass articles according to the invention, which were formed from flat glasses with a dimension 1150 ⁇ 850 mm by the method according to the invention:
• Inventive glass articles or glass articles produced according to the invention preferably have a thickness tolerance ⁇ 50 ⁇ m, a thickness variation ⁇ 50 ⁇ m, a warp ⁇ 0.05% and a waviness ⁇ 150 nm (the last two values refer to the undeformed region of the glass article). LIST OF REFERENCE NUMBERS

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• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Organic Chemistry (AREA)
• Mechanical Engineering (AREA)
• Re-Forming, After-Treatment, Cutting And Transporting Of Glass Products (AREA)

Applications Claiming Priority (4)

Publications (2)

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ID=51206244

Family Applications (1)

Country Status (3)

Cited By (2)

Families Citing this family (5)

Citations (8)

Family Cites Families (8)

• 2014
  • 2014-01-20 DE DE201410200921 patent/DE102014200921A1/de not_active Ceased
  • 2014-02-03 WO PCT/EP2014/000272 patent/WO2014121914A2/de active Application Filing
  • 2014-02-05 TW TW103103922A patent/TW201437158A/zh unknown

Patent Citations (8)

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