JP6820928B2 - Low-E glass heat treatment method and system - Google Patents

Description

Embodiments of the present invention relate to heat treatment methods and systems for Low-E glass.

In recent years, in the era of high value, countries around the world have selected the solution of energy problems as a top priority issue and are urgently preparing for countermeasures. One of the measures is to reduce energy consumption through technologies that can reduce energy loss and increase efficiency in major energy use sectors such as industrial sites and buildings.

In a building, windows and doors have about 8 to 10 times lower heat insulation properties than walls, so heat loss through doors and windows is the heat loss of the entire building. It is so serious that it accounts for about 25% to about 45% of the total.

Therefore, Low-E glass (LOW-Emissivity Glass) is used in order to reduce heat loss in doors and windows. Low-E glass has a structure in which one side of ordinary glass is coated with a metal film having high infrared reflectance, and has a single-layer or multi-layer structure. The metal film transmits visible light to improve indoor daylighting, reflects infrared rays to reduce heat transfer indoors and outdoors, and suppresses changes in indoor temperature as much as possible.

Low-E glass is composed of hard Low-E (hard low-E) by a pyrolysis method and soft Low-E (software low-E) by a sputtering method, depending on the coating manufacturing method. It can be roughly divided into.

In the hard Low-E manufacturing method, a metal solution or metal powder is sprayed onto the flat glass during the manufacturing process of the float flat glass to perform thermal coating. The coating material is usually a single material of metal oxide (eg SnO ₂ ). The merit of the existing hard Low-E manufacturing method is that since the thermal coating is performed, the coating hardness and durability are strong, and as a result, heat treatment such as strengthening can be performed. However, there is a drawback that the hue is simple and the coating film is turbid because the use of a plurality of metals is restricted.

On the other hand, in the soft Low-E manufacturing method, a float plate glass that has already been produced is provided as a metal target plate of a separate vacuum chamber, and a metal such as silver (Ag), titanium (Titanium), or stainless steel (Stainless Steel) is used. Produced by coating with a multi-layer thin film. The merit of the existing soft Low-E manufacturing method is that it has high transparency, various hues can be realized through the use of a plurality of metals, and it is excellent in optical performance and thermal performance. However, the coating hardness and durability are weaker than those of Hard Low-E, and there is a drawback that a separate edge stripping processing facility is required when manufacturing the double glazing.

As described above, at present, a new manufacturing technique for Low-E glass that compensates for the shortcomings of the hard Low-E manufacturing method and the soft Low-E manufacturing method and has improved radiation performance is desired.

The present invention has been devised to solve the problems of the above-mentioned conventional techniques, and an object thereof is to improve the efficiency of radiation performance of Low-Emissivity glass used for doors and window systems. It is to provide a heat treatment method and system of Low-E glass which can be improved well and can make up for the shortcomings of Low-E glass by the existing manufacturing method.

In order to achieve the above-mentioned object, according to one aspect of the present invention, a step of carrying a glass plate having a metal film formed on one side onto one side of a transport device and a step of carrying the glass plate from one side of the transport device to the other Before or after the step of selectively heat-treating the metal film using the microwave of the first temperature and the step of heat-treating the metal film using the microwave in the first region of the transport direction toward the side of the transport direction. A method for heat-treating Low-E glass, which comprises a step of selectively heat-treating the metal film with a laser beam having a second temperature in a second region located at the front end or the rear end of the first region. Provided.

In one embodiment, preferably, in the step of heat treatment using the microwave, the metal film is selectively heated to a depth of 1 μm from the surface.

In one embodiment, preferably, in the step of heat treatment using the microwave, the metal film is heated in a temperature atmosphere of 200 ° C. to 500 ° C.

In one embodiment, the frequency of the microwave is preferably several GHz and the width of the microwave is 10 cm to 15 cm.

In one embodiment, the metal film preferably contains silver (Ag) as a main component.

In one embodiment, preferably, the conductivity of the metal film is greater than the conductivity of copper (Cu) at the first temperature.

In one embodiment, preferably the Low-E glass heat treatment method is located before or after the step of heat treatment using the microwave, preferably before or after the first region in the transport direction. Further including a step of selectively heat-treating the metal film with a laser beam having a second temperature different from the first temperature in the second region. The second temperature may be higher than the first temperature, but the present invention is not limited to this, and can be changed according to the arrangement relationship.

In one embodiment, preferably, in the step of heat-treating with the laser beam, the metal film is heated in a temperature atmosphere of 500 ° C. to 650 ° C.

In one embodiment, preferably, the preheating temperature is lower than the first temperature in front of the first region in the transport direction before the step of using the microwave or heat treatment with the laser beam. It further comprises the step of preheating the glass plate or the metal film.

In one embodiment, preferably, in the step of heat treatment with the laser beam, the metal film is selectively heated from the surface to a depth of 1 μm with a line beam orthogonal to the transport direction.

In one embodiment, preferably, in the step of heat-treating with the laser beam, the metal film is heated in a temperature atmosphere of 500 ° C. to 650 ° C.

In one embodiment, preferably, the Low-E glass heat treatment method is such that the first region in front of the first region in the transport direction is prior to the step of using the microwave or heat treating with the laser beam. Further includes a step of preheating the glass plate or the metal film at a preheating temperature lower than the temperature of the above.

In order to achieve the above-mentioned object, according to the other aspect of the present invention, a transport device that carries in a glass plate having a metal film formed on one side from one side and a transport device that carries in the glass plate from one side to the other. A microwave module which is arranged in a first region in a transport direction toward the side and emits a microwave of a first temperature, and a laser module which is arranged at the front end or the rear end of the microwave module. The microwave module selectively heat-treats the surface of the metal film with the microwave, and the laser module is located in a second region located at the front end or the rear end of the first region in the transport direction. A heat treatment system for Low-E glass is provided, which selectively heat-treats the metal film with a laser beam at a second temperature.

In one embodiment, preferably, the microwave module selectively heats from the surface of the metal film to a depth of 1 μm. Further, preferably, the microwave module heats the metal film in a temperature atmosphere of 200 ° C. to 500 ° C. Further, preferably, the frequency of the microwave is several GHz, and the width of the microwave is 10 cm to 15 cm.

In one embodiment, the metal film preferably contains silver (Ag) as a main component. It should be noted that preferably, a dielectric layer is provided between the metal film and the glass plate.

In one embodiment, preferably, the Low-E glass heat treatment system is provided in a second region located in front of or behind the first region in the transport direction and is different from the first temperature. A laser module for selectively heat-treating a metal film with a laser beam having a temperature of 2 is further provided.

In one embodiment, preferably, the laser module extends in a direction orthogonal to or intersecting the transport direction and heats the metal film with a line beam having a beam width of 1 mm or less.

In one embodiment, preferably, the laser module heats the metal film in a temperature atmosphere of 500 ° C. to 650 ° C.

In one embodiment, preferably, the Low-E glass heat treatment system uses the glass plate or the glass plate or the glass plate at a preheating temperature lower than the first temperature at the front end of the microwave module and the laser module with reference to the transport direction. Further provided is a preheating device for preheating the metal film.

As described above, according to the embodiment of the present invention, the radiation performance of the Low-E glass is improved by selectively heating and heat-treating the coating film of the Low-E glass (low-emissivity glass). Can be done.

Further, since the glass is heated at a high temperature instantaneously under the condition that the glass is not broken, the metal film can be selectively heat-treated without damaging the metal film. Since the coating film is selectively heated, there is an advantage that the temperature can be easily controlled and a large area of glass can be evenly heat-treated.

Furthermore, by further performing laser beam heating, preheating, or a combination thereof in addition to heating using microwaves, surface selective heating using microwaves can be efficiently applied to significantly improve the performance of Low-E glass. It can be improved and the existing problems in the manufacturing process can be solved.

That is, it is possible to solve the problem that the Low-E glass manufactured during the heat treatment with the existing hot air cannot be cut, and it is possible to solve the problem that the radiation performance is difficult to adjust. In addition, it is possible to reduce the replacement cost of the lamp when using the existing flash lamp, and to improve the slow takt time or cycle time of the Low-E glass. it can. In addition, it is possible to prevent the occurrence of glass discoloration that occurs when an existing electron beam is used, and it is possible to reduce a relatively high energy consumption.

It is a schematic block diagram for the heat treatment system of Low-Emissivity Glass by one Embodiment of this invention. It is a graph for demonstrating the operation principle of the microwave module used in the heat treatment system of Low-E glass of FIG. It is an HR-TEM image of the Low-E glass for demonstrating the heat treatment performance of the microwave module of FIG. It is sectional drawing for demonstrating the glass plate for Low-E glass which can be adopted in the heat treatment system of Low-E glass according to embodiment of this invention. It is a schematic block diagram for the heat treatment system of Low-E glass according to another embodiment of this invention. It is a schematic cross-sectional view with respect to the part of the preheating apparatus of the glass convection oven for explaining the structure of a part of the heat treatment system of Low-E glass of FIG. It is a figure which shows the operating state of the laser module which can be adopted in the heat treatment system of Low-E glass by still another Embodiment of this invention. FIG. 5 is a schematic cross-sectional view of a portion of the laser module for explaining the configuration and operating principle of the laser module used in the Low-E glass heat treatment system of FIG. 7. It is a figure which shows the arrangement form of the microwave module and the laser module which can be adopted in the heat treatment system of Low-E glass by still another Embodiment of this invention. It is a flowchart for demonstrating the heat treatment method of Low-E glass by still another Embodiment of this invention.

The present invention can be modified in various ways and may have various embodiments, but specific embodiments are illustrated in the drawings and described in detail. However, this is not intended to limit the invention to any particular embodiment and should be understood to include any modifications, equivalents or alternatives contained within the ideas and technical scope of the invention. is there. The same components are designated by the same reference numerals for ease of description of each drawing.

Terms such as first, second, A, and B can be used to describe the various components, but these components should not be limited by these terms. These terms are used only to distinguish one component from another. For example, within the scope of the rights of the present invention, the first component can be named the second component, and similarly, the second component can also be named the first component. is there. The terms and / or include any one of a combination of a plurality of related entries or a plurality of related entries.

When one component is mentioned to be "connected" to another, or when it is mentioned to be "connected", it may be directly connected to the other component or directly connected. It should be understood that other components may intervene between them. On the other hand, when one component is mentioned to be "directly connected" to another, or when it is mentioned to be "directly connected", the other component is between them. It should be understood that it does not exist.

The terms used herein are merely used to describe a particular embodiment and are not intended to limit the invention. The singular expression includes multiple expressions in the context, unless otherwise noted. In the present specification, terms related to "including", "providing", "having", etc. are the features, numbers, stages, operations, components, parts, or combinations thereof described above the specification. Is merely to indicate the existence of, and does not preclude the existence or addability of one or more other features, numbers, stages, actions, components, parts or combinations thereof. Should be understood.

Also, in this specification, unless there is room for misunderstanding, when a subscript or superscript of one character has another subscript or superscript, the subscript is for ease of display. Alternatively, it can be displayed in the same form as other subscripts or superscripts of superscripts.

Unless otherwise noted herein, any term used herein, including technical or scientific terms, is generally understood by those with ordinary knowledge in the technical field to which the present invention belongs. It has the same meaning as the one. Commonly used terms such as those defined in a dictionary should not be construed as having a meaning consistent with the contextual meaning of the relevant description and are ideal unless expressly defined herein. It is not interpreted as a formal or overly formal meaning.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic configuration diagram for a heat treatment system of Low-Emissivity Glass according to an embodiment of the present invention.

Referring to FIG. 1, the Low-E glass heat treatment system 100 according to the present embodiment includes a transfer device 20 and a microwave module 30. The Low-E glass heat treatment system 100 may include a glass convection oven in which the microwave module 30 is arranged and a chamber that performs a corresponding function.

The transfer device 20 may be assembled in a glass convection oven or chamber to transfer the glass plate 10 from the outside to the inside of the oven or the chamber and from the inside to the outside again. A metal film may be formed in advance on one side of the glass plate 10.

The metal film may be referred to as a Low-E coating layer, and the conductivity or conductivity of the metal film is copper (Cu) at a temperature (hereinafter referred to as a first temperature) formed on the metal film by microwaves. ) May be greater than the conductivity. The metal film may be silver (Ag) or may contain silver (Ag) as a main component.

The glass plate 10 may be loaded from one side of the transport device 20 and transported to the other side of the transport device 20, for example, in the first direction D1. The conveyor belt type 20 may be a conveyor belt type.

In the Low-E glass heat treatment system 100 of the present embodiment, the portion where the glass plate 10 having the metal film formed on one side is carried into the transfer device 20 may be referred to as a loading zone Z0, and may be referred to as a microwave. The portion where the wave module 30 is arranged may be referred to as a microwave zone Z2, and the portion where the glass plate 10 on which the crystallized metal film is formed is carried out from the transport device 20 is a carry-out zone (carry-out zone). It may be called unloading zone) Z6.

In the microwave zone Z2, the surface of the metal film on the glass plate 10 may be selectively heated by the microwave 32 forming a temperature atmosphere (200 to 500 ° C.). Here, the microwave module 30 may control the microwave 32 so that the metal film is heated to a depth of 1 μm or less from the surface of the metal film.

The frequency of the microwave 32 may be several GHz, and the width of the microwave 32 may be 10 cm to 15 cm. The longitudinal direction of the microwave 32 may be orthogonal to the first direction D1, and the width of the microwave 32 may be the wave width in the first direction D1.

The frequency and width of the microwave 32 described above can be adjusted according to the conductivity of the metal film. For example, if the conductivity of the metal film is high, it may be heated to a relatively shallow depth because the conductivity on the surface of the metal film is high at the same frequency and temperature. That is, in the present embodiment, the intensity of the microwave is increased so that the microwave heat treatment can selectively heat the surface of the metal film below a predetermined depth corresponding to the threshold value at which the surface current of the metal film starts to decrease sharply. The frequency or irradiation width may be determined.

FIG. 2 is a graph for explaining the operating principle of the microwave module used in the heat treatment system for Low-E glass of FIG.

Referring to FIG. 2, in the present embodiment, the metal film on the glass plate heated by the microwave module has a surface at a microwave output density (power) or energy of a predetermined intensity (Pa) or more supplied. It has a predetermined surface current from to a predetermined depth t1.

Such properties can be an important factor in uniformly heat-treating a large-area glass plate to crystallize a metal film. That is, it is uniform enough to avoid damage or breakage of the glass layer so that the thermal stress inside the glass plate does not exceed the burst coefficient of the glass, and it can be used as a condition for rapid heating within a short time. is there. In the present embodiment, the surface of the metal film is selectively heated to a depth of 1 μm or less, preferably shallower than 1 μm, from the surface of the metal film by using a microwave module. At this time, the metal film may be silver (Ag) or a material containing silver (Ag) as a main component.

The metal film is copper, gold, Chromium, aluminum, Tungsten, zinc, brass, Nickel, iron, bronze. It may further contain at least one substance selected from (Bronze), platinum (platinum) and the like. In that case, the conductivity of the metal film is usually low, and the heating depth of the surface of the metal film is deep under the same microwave surface selective heating conditions. Therefore, in order to uniformly heat-treat a large-area glass plate, Microwave irradiation conditions such as microwave frequency and wave width may be adjusted so that the surface selective heating depth by microwave is 1 μm or less.

FIG. 3 is an HR-TEM image of Low-E glass for explaining the heat treatment performance of the microwave module of FIG.

The Low-E glass heat treatment system according to the present embodiment selectively heats the surface of the metal film on the glass plate by using the characteristic of microwave (microwave) that the glass surface absorption rate is high.

The glass plate for use as Low-E glass includes a glass layer 11 and a Low-E layer (low), as shown in the high resolution (HR) transmission electron microscope (TEM) image of FIG. -Emissivity layer) 12 and a metal layer 13 may be provided. In the present embodiment, the glass layer 11 may be referred to as a glass substrate, and the metal layer 13 may be a platinum (Pt) layer.

As described above, in the present embodiment, the metal film on the large-area glass plate for Low-E glass can be uniformly crystallized by using the microwave characteristic that the glass surface absorption rate is high.

Further, the higher the conductivity of the metal film, the shallower the penetration depth due to surface selective heating. Therefore, in the present embodiment, a material containing silver (Ag) or silver (Ag) as a main component is used as the metal film. It can be used to control the surface penetration depth of the microwave to the metal film to be 1 μm or less, whereby the heat treatment performance can be improved.

Further, when laser processing / heat treatment is performed in the production of Low-E glass, microwave heat treatment can be performed before laser beam heat treatment to improve the efficiency of laser processing / heat treatment.

FIG. 4 is a cross-sectional view for explaining a glass plate for Low-E glass that can be adopted in the heat treatment system for Low-E glass according to the embodiment of the present invention.

Referring to FIG. 4, the glass plate 10 according to the present embodiment may include a glass layer 11, a Low-E layer 12 on the glass layer, and a metal film 13 on the Low-E layer. The metal film 13 can be crystallized after the heat treatment. The Low-E layer 12 may be formed of zinc oxide or the like, and the metal film 13 may be formed of silver (Ag).

Further, the glass plate 10 may further include a first dielectric 14 disposed between the glass layer 11 and the Low-E layer 12. The first dielectric 14 may be formed of a material such as titanium oxide, and may be referred to as a first dielectric layer.

Further, the glass plate 10 may further include another Low-E layer 15 disposed on the metal layer 13 on the upper side of the glass layer 11, and may be on the other Low-E layer 15. The second dielectric 16 may be laminated. The second dielectric 16 may be formed of a nitride film such as silicon nitride.

According to this embodiment, the metal film 13 can be efficiently crystallized by using a microwave module, whereby the production efficiency of Low-E glass can be improved, and the produced Low-E glass can be improved. Performance can be improved. The performance of Low-E glass includes reflection performance.

FIG. 5 is a schematic configuration diagram for a heat treatment system for Low-E glass according to another embodiment of the present invention.

Referring to FIG. 5, the Low-E glass heat treatment system 100A according to the present embodiment includes a transfer device 20, a microwave module 30, and a preheater (preheater) 40. The Low-E glass heat treatment system 100A can enhance the effect of surface-selective heating of the metal film on the glass plate 10 by microwaves by performing the preheating step in advance.

The preheating device 40 may be arranged on one side of the transport device 20. The portion of the transport device 20 on which the preheating apparatus 40 is arranged or the portion where the preheating step is performed may be referred to as a preheating zone (preheater zone) Z1. The preheating zone Z1 may be located next to the carry-in zone or may be arranged so as to overlap most of the carry-in zone.

The preheating temperature may be lower than the temperature of the microwave heat treatment (first temperature). The preheating temperature may be about 200 ° C. or lower, or may be the temperature on the metal film.

The preheating device 40 may be arranged as a hot air device, a heater, or the like. By using the preheating device 40, the entire glass plate 10 having a metal film formed on its surface can be heated. Preheating can be performed by using various methods under the condition that the glass plate 10 is not broken. However, the preheating atmosphere and conditions are not particularly limited as long as the metal film can be preheated to about 200 ° C. before the microwave heat treatment.

After the preheating step, the surface of the metal film on the glass plate 10 is selectively heated by the microwave 32 in the microwave zone Z2, and then the glass plate and the crystallized metal film are gradually heated in the slow cooling zone Z4. Can be cooled to.

FIG. 6 is a schematic cross-sectional view of a portion of the preheater of the glass convection oven for explaining the configuration of a portion of the Low-E glass heat treatment system of FIG.

Referring to FIG. 6, the Low-E glass heat treatment system according to the present embodiment may include a glass convection oven. The glass convection oven may include a frame 80 and a chamber 90 fixed on top of the frame 80. The chamber 90 may include a vacuum chamber.

A hot air device may be arranged on the upper part of the chamber 90. The hot air device may include a heater 41, a blower 42, and a pipe 43 that connects the heater 41 and the blower 42 to the internal space of the chamber 90 so that fluid can communicate with each other.

A transport device may be assembled in the chamber 90. The transport device includes a rotary shaft 22 that penetrates the chamber 90 in a direction orthogonal to the transport direction of the glass plate 10, a roller 23 that is assembled to the rotary shaft 22 and rotates, and a motor 25 that applies a driving force to the rotary shaft 22. May be good. The motor 25 may be arranged on one side outside the chamber 90.

The glass convection oven described above may be configured to be movable by wheels arranged at the lower end.

FIG. 7 is a schematic configuration diagram for a heat treatment system of Low-Emissivity Glass according to still another embodiment of the present invention.

Referring to FIG. 7, the Low-E glass heat treatment system 100H according to the present embodiment includes a transfer device 20, a microwave module 30, a laser module 50, mirrors 61, 62, and a camera 70. In the Low-E glass heat treatment system 100H, the metal film on the glass plate 10 is heat-treated with a microwave using the surface selection method, and then heat-treated again with a laser beam using the surface selection method to efficiently crystallize the metal film. As a result, the radiation performance of the metal film or the Low-E glass with the metal film is greatly improved.

The laser module 50 may be operated so that the heat treatment temperature in the metal film is about 500 ° C. to about 650 ° C. The laser module 50 may irradiate the laser beam 52 diagonally in the direction opposite to the transport direction of the glass plate 10, but the present invention is not limited to this, and the laser beam is obliquely irradiated in the transport direction. It may be arranged to irradiate. Needless to say, depending on the embodiment, a plurality of laser modules that emit laser beams diagonally in the transport direction and in directions opposite to the transport direction can be used.

Further, in order to increase the heat treatment efficiency of the laser beam 52, a mirror that reflects the laser beam 52 on the metal film on the glass plate 10 may be arranged again.

The mirror may include a first mirror 61 and a second mirror 62. The first mirror 61 may be arranged below the glass plate 10 and reflect the laser beam 52 traveling from the laser module 50 through the glass plate 10. The second mirror 62 may reflect the laser beam reflected from the first mirror 61 on the glass plate 10 again. According to such a reflection structure, the laser beam has at least one staggered traveling path and can penetrate the glass plate 10 a plurality of times.

The laser beam 52 may have a line beam shape that is parallel to the main surface or the upper surface of the glass plate 10 and extends in a direction orthogonal to the transport direction D1 of the glass plate 10. By using a high-power large-scale line beam (laser beam), a large-area glass plate can be efficiently and uniformly heat-treated.

The camera 70 is for monitoring the crystallized metal film on the glass plate 10 exiting through the slow cooling zone Z4. The camera 70 is a component of the monitoring system and can be connected to the monitor of the monitoring system via a wired or wireless network.

The camera 70 and the monitor are examples of a monitoring system and are means for confirming the state of the crystallized metal film and the state of the heat treatment of the glass plate 10, and are configured to perform functions corresponding to such means. If it is an element, it is not particularly limited.

The portion of the transport device 20 on the other end side where the monitoring process is performed is referred to as a monitoring zone Z5. At least a part of the monitoring zone Z5 may overlap with the carry-out zone.

FIG. 8 is a schematic cross-sectional view of the laser module portion for explaining the configuration and operating principle of the laser module adopted in the heat treatment system for Low-E glass of FIG.

Referring to FIG. 8, the laser module 50 used in the Low-E glass heat treatment system according to the present embodiment may be configured in consideration of the speed of the flat glass production line.

The laser module 50 may include a large number of laser heads or may include a laser diode array. The laser module 50 may be arranged at a predetermined distance L1 from the glass plate 10. The separation distance may be about 250 mm to about 300 mm.

The laser beam 52 may have a shape in which the overall beam width becomes wider in the longitudinal direction D2 of the line beam as it advances from the laser module 50 to the glass plate 10 or the first mirror 61. The beam width of the line beam may be 1 mm.

When the line beam having the above-mentioned beam width is used, there is an advantage that the selective heating of the surface of the metal film by the laser beam can be uniformly performed on the transfer device of a large glass plate having a predetermined production speed or transfer speed. The transport speed may be 50 mm / s to 150 mm / s.

FIG. 9 is a diagram showing a modified example of the arrangement form of the microwave module and the laser module that can be adopted in the heat treatment system for Low-E glass according to still another embodiment of the present invention.

Referring to FIG. 9, the Low-E glass heat treatment system 100K according to the present embodiment includes a transfer device 20, a microwave module 30, a laser module 50, mirrors 61, 62, and a camera 70. In the Low-E glass heat treatment system 100K, the metal film on the glass plate 10 is heat-treated by the surface selection method using the laser module 50, and the metal film is efficiently heat-treated by the surface selection method using the microwave module 30. It is crystallized, which greatly improves the radiation performance of the metal film or the Low-E glass with the metal film.

The laser module 50 can be operated so that the heat treatment temperature in the metal film is about 500 ° C. to about 650 ° C. The laser module 50 may irradiate the laser beam 52 diagonally in the direction opposite to the transport direction of the glass plate 10, but the present invention is not limited to this, and the laser beam is obliquely irradiated in the transport direction. It may be arranged to irradiate. Needless to say, depending on the embodiment, a plurality of laser modules that emit laser beams diagonally in the transport direction and in directions opposite to the transport direction can be used.

As described above, according to the present embodiment, the heat treatment temperature of the metal film can be controlled by combining at least one or more microwave modules 30 and at least one or more laser modules 50. According to such a method, the surface of the metal film can be selectively heat-treated at a high temperature, and the metal film can be efficiently crystallized.

FIG. 10 is a flowchart for explaining a heat treatment method for Low-E glass according to still another embodiment of the present invention.

Referring to FIG. 10, the heat treatment method for Low-E glass according to the present embodiment is a main step of selectively heating only a portion having a predetermined thickness on the surface of a metal film on a glass plate using a microwave module. In addition, a preheating process using a hot air device, a heater, or the like and a secondary selective surface heat treatment process using a laser beam may be further included.

In the present embodiment, a case where preheating with hot air, surface selective heat treatment with microwaves, and surface selective heat treatment with a laser beam are performed in the order described will be mainly described.

First, the glass plate may be carried into one side of the transport device (S121). A metal film may be arranged on one side of the glass plate. The metal film may be preformed on the glass plate by a method such as injection, coating, or sputtering. The transport device may transport the glass plate at a transport speed of 50 mm / s to 150 mm / s.

The surface of the metal film on the glass plate may then be selectively heated to a depth of less than 1 μm using microwaves in the microwave zone (S123). The metal film heated by microwaves can be crystallized.

The surface of the metal film may then be secondarily and selectively heated using a laser beam in the laser mirror zone (S124). The metal film heated by the laser beam can be crystallized.

Then, the glass plate or the metal film may be gradually cooled by using a heat exchanger in the slow cooling zone (S125).

Next, the glass plate on which the crystallized metal film is formed (hereinafter, referred to as Low-E glass or Low-E glass semi-finished product) may be carried out from the transport device (S126).

According to the present embodiment, the metal film on the glass plate is preheated by a hot air device, primarily heated by a microwave, and secondarily heated by a laser beam to obtain Low-E glass having excellent radiation performance. Can be manufactured. That is, the metal film on the Low-E coating layer can be crystallized without damaging the Low-E coating layer by selectively heating the surface of the metal film on the glass plate.

On the other hand, in the present embodiment, the step (S123) of selectively heat-treating the surface of the metal film using microwaves is performed before the step (S124) of selectively heat-treating the surface of the metal film using a laser beam. It is not limited to the above, and may be performed after the heat treatment step using a laser beam. In that case, the temperature of the surface of the metal film by the laser beam (second temperature) based on the temperature of the surface of the metal film by the microwave (first temperature) is based on the arrangement relationship between the microwave module and the laser module. ) Is preferably higher than the first temperature. However, the temperature of the surface of the metal film by the laser module may be lower than the first temperature depending on the process conditions such as the arrangement of the modules, the material of the metal film, and the thickness. For example, a plurality of laser modules may be arranged before and after the microwave module, respectively, in which case the plurality of laser modules may be controlled to operate at different metal film surface temperatures.

Further, in the present embodiment, before the step (S123) of heat treatment using microwaves and the step (S124) of heat treatment using a laser beam, a glass plate, a metal film, or a glass plate, a metal film, or a glass plate, a metal film, or a metal film is used in a preheating zone using a hot air device. A step (S122) of preheating both of these may be further included. In this case, when the metal film is rapidly heated to a relatively high temperature by a microwave module or a laser module, there is an advantage that the heat diffusion or heat dispersion of the metal film can be efficiently assisted by using the preheat treatment. is there.

Thus, according to rapid selective thermal processing (RSTP) methods and systems that use the combined energy of hot air and microwaves and laser beams, 600 ° C. to 700 ° C. for heat treatment of metal films of Low-E glass. It is possible to efficiently realize a temperature atmosphere of ° C., which makes it possible to increase the efficiency of the Low-E glass for the heat treatment process, and the low of a large area with ultra-high efficiency without damage to the glass layer and the Low-E layer. -E There is an advantage that heat treatment of a uniform metal film of glass can be easily performed. The ultra-high efficiency, large area Low-E glass may include a heat insulating glass panel having a thickness of 250 mm and dimensions of 800 mm × 1600 mm or more.

On the other hand, in the above-described embodiment, the heat treatment using microwaves can be replaced with the heat treatment by an induction heater (induction heater) using an induction coil or a heating body (mold insulator). In such an induction heating method, instead of conductivity, surface selective heating can be performed according to the electrical resistivity and relative magnetic permeability of the material. The electrical resistivity refers to the electrical resistance of an object having a unit length or a unit volume of a certain object. The relative magnetic permeability of a material is a value obtained by dividing the magnetic permeability of a pure material by the magnetic permeability of a vacuum, and can be calculated with reference to 1, which is the relative magnetic permeability of copper.

That is, in induction heating, the magnetic field line density (magnetic flux density) represented by the number of magnetic field lines that vertically pass through a unit area of the metal film is controlled so as to selectively heat the metal film to 1 μm or less from the surface. It may be realized. The induction heater for induction heating may be arranged closer to the metal film than the microwave module.

Although the above description has been made with reference to the preferred embodiments of the present invention, those skilled in the art will not deviate from the ideas and areas of the present invention described in the claims below. It should be understood that the present invention can be modified and modified in various ways.

Claims (7)

A step of carrying a glass plate having a metal film formed on one side to one side of a transport device, and
A step of selectively heat-treating the metal film using microwaves at a first temperature in a first region in a transport direction from one side of the transport device to the other side.
Before or after the step of heat treatment using the microwave, the metal film is selected by using a laser beam at a second temperature in a second region located at the front end or the rear end of the first region in the transport direction. Including the step of heat-treating
The metal film is mainly composed of silver and contains one or more substances selected from copper, gold, chromium, aluminum, tungsten, zinc, brass, nickel, iron, bronze, and platinum.
The thermal conductivity of the metal film heat-treated by microwaves at the first temperature is larger than the thermal conductivity of copper at the first temperature, and the first temperature is 200 ° C. to 500 ° C. The width of the microwave is 10 cm to 15 cm, the width direction of the microwave is the same as the transport direction, and in the step of heat treatment using the microwave, the metal film is heated to a depth of 1 μm from the surface. And
A second temperature for heat treating the metal film by the laser beam is 500 ° C. to 650 ° C., wherein the laser beam is a line beam, the width of the line beam Ri der below 1 mm, the line beam Orthogonal to the transport direction,
A method for heat-treating Low-E glass. Wherein in the step of heat treatment with a laser beam, it is heated to a depth 1μm from the surface of the metal film in the line beam, the heat treatment method of the Low-E glass according to claim 1. Before the step of heat treatment with the microwave or before the step of heat treatment with the laser beam, the glass plate or the metal at a preheating temperature lower than the first temperature in front of the first region in the transport direction. The method for heat-treating Low-E glass according to claim 1, further comprising a step of pre-heat-treating the film. A Low-E glass heat treatment system to which the Low-E glass heat treatment method according to claim 1 is applied.
The transport device that carries in a glass plate with a metal film formed on one side from one side, and
A microwave module disposed in the first region in the transport direction from one side to the other of the transport device and emitting microwaves at the first temperature.
A laser module arranged at the front end or the rear end of the microwave module,
With
In the microwave module, the surface of the metal film is selectively heat-treated with the microwave.
The laser module selectively heat-treats the metal film with a laser beam at the second temperature in the second region located at the front end or the rear end of the first region in the transport direction .
The metal film is mainly composed of silver and contains one or more substances selected from copper, gold, chromium, aluminum, tungsten, zinc, brass, nickel, iron, bronze, and platinum.
The thermal conductivity of the metal film heat-treated by the microwave at the first temperature is larger than the thermal conductivity of copper at the first temperature, and the first temperature is 200 ° C. to 500 ° C. The width of the microwave is 10 cm to 15 cm, the width direction of the microwave is the same as the transport direction, and the microwave module heats from the surface of the metal film to a depth of 1 μm.
The second temperature for heat-treating the metal film by the laser beam is 500 ° C. to 650 ° C., the laser beam is a line beam, the width of the line beam is 1 mm or less, and the line beam is said. Orthogonal to the transport direction,
Low-E glass heat treatment system. The laser module heats the metal film from the surface to a depth of 1 μm with the laser beam.
The Low-E glass heat treatment system according to claim 4 . The Low-E glass heat treatment system according to claim 4 , wherein a dielectric layer is provided between the metal film and the glass plate. A preheating device for preheating the glass plate or the metal film at a preheating temperature lower than the first temperature at the front end of the microwave module and the laser module with reference to the transport direction is further provided .
The transport device transports the glass plate at a transport speed of 50 mm / s to 150 mm / s.
The Low-E glass heat treatment system according to claim 4 , wherein the laser module comprises a large number of laser heads or laser diode arrays for the line beam.