CN114734711B - Preparation method of laminated glass - Google Patents

Abstract

The invention relates to a preparation method of laminated glass, which comprises the following steps: s1, cutting to obtain a first glass substrate and a second glass substrate; s2, respectively carrying out heat treatment on the first glass substrate and the second glass substrate; s3, arranging an adhesive layer between the first glass substrate and the second glass substrate for re-lamination, wherein the thermal shrinkage rate of the adhesive layer is less than or equal to 1.5%; s4, performing glue repairing treatment on the first glass substrate and the second glass substrate after the bonding: removing the adhesive layers beyond the four sides of the glass substrate, so that the adhesive layers on the four sides of the glass substrate are aligned with the edges of the glass substrate; s5, prepressing; s6, moving the pre-pressed first glass substrate and second glass substrate into an autoclave for final pressing, and obtaining the laminated glass. The preparation method provided by the invention only relates to one-time repair, simplifies the process flow, reduces the production time and improves the production efficiency; the prepared laminated glass has no corner collapse and peeling, avoids discharge and rubber strip waste sheets during film coating, and improves the glass quality.

Description

A method for preparing laminated glass

Technical Field

The invention belongs to the technical field of laminated glass, and particularly relates to a method for preparing laminated glass.

Background Art

Laminated glass is made by sandwiching a flexible middle layer between two or more pieces of glass and processed under high temperature and high pressure. The middle layer has good toughness, strong adhesion and good penetration resistance, so laminated glass has good impact resistance. Even when laminated glass is broken by impact, the fragments still stick to the middle layer and do not splash, so it has a safety protection effect on human body and property. At the same time, because the middle layer (especially PVB film) is a tough, transparent and flexible material, it can also absorb ultraviolet rays and sound waves, so laminated glass has anti-ultraviolet and sound insulation properties, and is widely used in the automotive and construction fields. Due to its excellent performance, and with the introduction of relevant policies on the use of safety glass in building curtain walls by local governments, the proportion of laminated glass in the architectural glass market has gradually increased.

At present, the most widely used method for producing laminated glass is the autoclave method, which is widely used in industrial production due to its mature technology and large production capacity. However, in the existing method of producing laminated glass, in order to prevent the problem of shrinkage, a margin of about 3mm beyond the four sides of the glass is usually reserved before entering the roller pressing furnace after the sheets are joined (this is the first glue repair, which is a necessary process because the purchased glue layer size is often wider than the glass size, and the glue layer is usually rolled, and the glass substrate is square). After the first glue repair, pre-pressing (the speed range of the glass substrate can only be 1.3-1.4m/min, and the pre-pressing heating temperature must be less than or equal to 240℃) and final pressing are performed. After the glass comes out of the autoclave, there is excess glue around the laminated glass, and the unloading personnel will remove the excess glue around the laminated glass (the second glue repair is to make the glue layer on the four sides of the glass aligned with the edge of the glass). During the glue repair process after unloading, due to the corners of the glass Stress concentration, personnel operate at a high speed to improve the efficiency of glue repair, and the force is difficult to control smoothly, which can easily cause the glass to break corners and peel, affecting the appearance quality; at the same time, because the preparation method of laminated glass places the autoclave vertically, the residual glue at the contact point between the bottom edge of the glass and the autoclave trolley (see the arrow in Figure 3) is squeezed and difficult to clean, which can easily lead to coating discharge. At the same time, the secondary glue repair will produce glue strips (see the arrow in Figure 2), which specifically refers to the glue layer between the two glass substrates. After pre-pressing and final pressing, part of the glue layer will overflow to the surface of one glass substrate. Because the glue layer and the glass substrate are molecularly bonded, the bond is extremely strong, and the glue layer overflowing to the surface of one glass substrate is sticky and difficult to remove. This part cannot be coated during coating, and the overall coating is uneven, resulting in scrap after coating. The entire production process requires two glue repairs, with many processes, a high scrap rate, and large losses.

Summary of the invention

The purpose of the present invention is to provide a method for preparing laminated glass, so as to solve the problems that the existing preparation of laminated glass requires two glue repairs, has many processes, a high scrap rate and large losses.

In order to achieve the above object, a technical solution adopted by the present invention is:

A method for preparing laminated glass comprises the following steps:

S1, cutting to obtain a first glass substrate and a second glass substrate, and pre-treating the first glass substrate and the second glass substrate;

S2, heat-treating the pre-treated first glass substrate and the second glass substrate respectively by a physical tempering method;

S3, setting a glue layer between the first glass substrate and the second glass substrate for lamination, wherein the thermal shrinkage rate of the glue layer is less than or equal to 1.5%;

S4, performing glue repair on the first glass substrate and the second glass substrate after being joined, including: removing the glue layer beyond the four sides of the first glass substrate and the second glass substrate, so that the glue layers on the four sides of the first glass substrate and the second glass substrate are respectively trimmed with the corresponding edges of the first glass substrate and the second glass substrate;

S5, pre-pressing the first glass substrate and the second glass substrate after the glue repair;

S6, moving the pre-pressed first glass substrate and the second glass substrate into an autoclave for final pressing to obtain the laminated glass.

Preferably, in step S5, the moving speed of the glass substrate during pre-pressing is greater than or equal to 1.5 m/min and less than or equal to 3 m/min.

Preferably, in step S5, the heating temperature during pre-pressing is 260°C-300°C.

Preferably, in step S3, the adhesive layer between the first glass substrate and the second glass substrate is PVB, and the thickness of the adhesive layer is in the range of 1-2 mm.

Preferably, in step S3, the adhesive layer between the first glass substrate and the second glass substrate is SGP, and the thickness of the adhesive layer is in the range of 1.5-2.5 mm.

Preferably, in step S6, the autoclave is kept at a temperature in the range of 130-135° C., a pressure in the range of 12-12.2 bar, a time in the range of 40-60 min, and is cooled to below 45° C. for exhaust.

Preferably, in step S6, the autoclave is kept at a temperature in the range of 135-138° C., a pressure in the range of 12.2-12.5 bar, a time in the range of 90-120 min, and is cooled to below 45° C. for exhaust.

Preferably, in step S5, after the first glass substrate and the second glass substrate are pre-pressed after the glue repair, the furnace temperature is controlled at 55-75°C.

Preferably, in step S2, the heat treatment process is as follows: the furnace temperature is controlled at 680-720°C, the first glass substrate and the second glass substrate are uniformly heated and controlled at 610-630°C, and then quickly and uniformly cooled to room temperature within a preset time threshold range.

Preferably, in step S6, if the adhesive layer between the first glass substrate and the second glass substrate is PVB, the autoclave is kept at a temperature of 130-135° C., a pressure of 12-12.2 bar, and a time of 40-60 min, and is cooled to below 45° C. for exhaust;

In step S6, when the adhesive layer between the first glass substrate and the second glass substrate is SGP, the autoclave is kept at a temperature of 135-138°C, a pressure of 12.2-12.5 bar, a time of 90-120 min, and is cooled to below 45°C for exhaust.

Due to the application of the above technical scheme, the present invention has the following advantages compared with the prior art: the preparation method provided by the present invention only involves one glue repair, which simplifies the process flow, reduces production time, and improves production efficiency; the prepared laminated glass does not have chipping and peeling, avoids discharge and waste of glue strips during coating, and greatly improves the quality of laminated glass; because there is no need to repair the glue after final pressing, the laminated glass after final pressing can be directly transferred to the coating chamber, realizing the mechanization and automation of laminated glass processing.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of the structure of the laminated glass of the present invention;

Figure 2 is a photo of a laminated glass obtained by the prior art preparation method with a glue strip on the outer surface;

FIG3 is a photograph of laminated glass obtained by the existing preparation method.

In the above attached figure:

1-first glass substrate, 2-glue layer, 3-second glass substrate.

DETAILED DESCRIPTION

The present invention will be further described below in conjunction with the embodiments shown in the accompanying drawings.

A method for preparing laminated glass comprises the following steps:

S1, cutting to obtain a first glass substrate 1 and a second glass substrate 3, and pre-processing the first glass substrate 1 and the second glass substrate 3, wherein the pre-processing includes chamfering, rough grinding or fine grinding;

The first glass substrate 1 and the second glass substrate 3 are cut out according to the required substrate type, thickness and size, and the first glass substrate 1 and the second glass substrate 3 are edge processed as required, including chamfering, rough grinding or fine grinding.

S2, heat-treating the first glass substrate 1 and the second glass substrate 3 respectively by a physical tempering method;

In step S2, the heat treatment process is as follows: the furnace temperature is controlled at 680-720°C, the first glass substrate 1 and the second glass substrate 3 are uniformly heated and controlled at 610-630°C, and then quickly and uniformly cooled to room temperature within a preset time threshold range.

If the thickness of the first glass substrate 1 and the second glass substrate 3 are both 6 mm, during full tempering: the furnace temperature is controlled at 680-720° C., the glass is uniformly heated to 610-630° C., then cooled uniformly to 350-450° C. at 10-12° C./s by a wind pressure of 2500-3000 Pa, and then cooled uniformly to room temperature at 10-12° C./s by a wind pressure of 700-1200 Pa. Specifically, the furnace temperature is controlled at about 700° C., and the glass is uniformly heated to about 620° C.

If the thickness of the first glass substrate 1 and the second glass substrate 3 are both 6 mm, during semi-tempered treatment: the furnace temperature is controlled at 680-720° C., the glass is uniformly heated to 610-630° C., and then uniformly cooled to 350-450° C. at 1.5-2.5° C./s by a wind pressure of 100-120 Pa, and then uniformly cooled to room temperature at 10-12° C./s by a wind pressure of 700-1200 Pa. Specifically, the furnace temperature is controlled at about 700° C., and the glass is uniformly heated to about 620° C.

S3. Use deionized pure water to clean and dry the first glass substrate 1 and the second glass substrate 3, and then set a glue layer between the first glass substrate 1 and the second glass substrate 3 to close the glass substrates. The first glass substrate 1 and the second glass substrate 3 are arranged opposite to each other, and the first glass substrate 1 and the second glass substrate 3 are equal in length and width. The heat shrinkage rate of the glue layer 2 is less than or equal to 1.5%, and 0.5-1.5% is optimal.

The heat shrinkage rate of the adhesive layer 2 is tested by the following method: a 100mm*100mm sample is placed in a vacuum drying oven at a heating temperature of 80°C for 15 minutes, and then the length change of the sample before and after heating is measured.

The thermal shrinkage rate of the adhesive layer 2 is mainly affected by the casting speed and tension during its production process. The thermal shrinkage rate can be reduced by reducing the casting speed and tension.

S4, performing adhesive repair on the first glass substrate and the second glass substrate after lamination, including: removing the adhesive layer 2 beyond the four sides of the first glass substrate and the second glass substrate, so that the adhesive layer 2 on the four sides of the first glass substrate and the second glass substrate is aligned with the corresponding edges of the first glass substrate and the second glass substrate. The entire preparation process involves only one adhesive repair, which greatly simplifies the process flow and greatly improves production efficiency. Lamination is carried out in a constant temperature room with a temperature range of 22-28°C and a humidity of 18%-28%.

In step S3, the adhesive layer 2 between the first glass substrate 1 and the second glass substrate 3 is PVB, the thickness of the PVB adhesive layer 2 is in the range of 1-2 mm, and the thickness can be 1.14, 1.52 or 1.9 mm, wherein the PVB adhesive layer 2 is located between the air surface of the first glass substrate 1 and the tin surface of the second glass substrate 3.

In step S3, the adhesive layer 2 between the first glass substrate 1 and the second glass substrate 3 is SGP, the thickness of the SGP adhesive layer 2 is in the range of 1.5-2.5 mm, and the thickness can be 1.52 or 2.28 mm, wherein the SGP adhesive layer 2 is located between the tin surface of the first glass substrate 1 and the tin surface of the second glass substrate 3.

S5. Pre-pressing the first glass substrate and the second glass substrate after the glue repair. During the pre-pressing, the moving speed of the glass substrate is greater than or equal to 1.5 m/min and less than or equal to 3 m/min. The pre-pressing heating temperature is 260° C.-300° C., and the rolling pressure is 6-8 bar. Pre-pressing at a faster speed and a higher temperature can prevent the glue layer 2 between the first glass substrate 1 and the second glass substrate 3 from shrinking inward toward the center, and can always keep the glue layers 2 on the four sides of the first glass substrate 1 and the second glass substrate 3 flush with the corresponding edges of the first glass substrate 1 and the second glass substrate 3.

In step S5, after the first glass substrate and the second glass substrate are pre-pressed after the glue is repaired, the furnace temperature is controlled at 55-75°C.

The first glass substrate 1 and the second glass substrate 3 after the glue repair are pre-pressed by a constant temperature convection process. Specifically, the first glass substrate 1 and the second glass substrate 3 after the glue repair are placed in a convection roller pressing furnace for convection heating. The convection roller pressing furnace includes a heating zone and a roller pressing zone arranged in sequence. The heating zone includes a plurality of convection wind boxes. Two sets of convection wind boxes are arranged on the left and right sides of the upper part of the first glass substrate 1 and the second glass substrate 3, and two sets of convection wind boxes are arranged on the left and right sides of the lower part. Each convection wind box corresponds to a 1.1KW fan, and the speed is controlled at 1000-1400r/min. There are multiple heating wires distributed in front of the fan. The fan is used to transfer the heat generated by the heating wire to the glass. Each heating wire is 3000W and is used to generate a heat source. The hot air is blown to the glass surface by the convection fan, so that gas convection is formed in the upper and lower spaces of the glass substrate, and the glass and the glue layer are quickly and evenly heated. The first glass substrate 1 and the second glass substrate 3 are heated by convection and then rolled in a rolling zone by a pressing roller, the pressing roller is an air pressure rubber roller, and the speed of the glass substrate is set to 1.5-3 m/min (meter/minute).

The constant temperature convection roller pressing process is adopted to avoid heating instability caused by temperature difference changes in the convection roller pressing furnace, and the adhesive layer 2 and the glass substrate are fully and evenly heated without large-area bubbles, thereby improving production quality.

Alternatively, the pre-pressing is performed using an infrared radiation heating furnace with a heating temperature of 260°C-300°C.

S6, moving the pre-pressed first glass substrate and the second glass substrate into an autoclave for final pressing to obtain a laminated glass. The autoclave is a cavity, and the pressure on each part of the laminated glass in the autoclave is balanced. During the final pressing process, the adhesive layer 2 shrinks very little and is basically invisible, which is equivalent to the adhesive layer 2 on the four sides of the first glass substrate 1 and the second glass substrate 3 being flush with the corresponding edges of the first glass substrate 1 and the second glass substrate 3.

In step S6, if the adhesive layer 2 between the first glass substrate 1 and the second glass substrate 3 is PVB, the autoclave is kept at a temperature of 130-135°C, a pressure of 12-12.2 bar, and a time of 40-60 min, and is cooled to below 45°C for exhaust.

In step S6, when the adhesive layer 2 between the first glass substrate 1 and the second glass substrate 3 is SGP, the autoclave is kept at a temperature of 135-138°C, a pressure of 12.2-12.5 bar, a time of 90-120 min, and is cooled to below 45°C for exhaust.

A laminated glass, referring to FIG1 , is prepared by the above-mentioned laminated glass preparation method. The laminated glass includes a first glass substrate 1, a second glass substrate 3, and a glue layer 2 bonded between the first glass substrate 1 and the second glass substrate 3. The glue layer 2 is PVB or SGP. If the glue layer 2 is PVB, the thickness of the glue layer is in the range of 1-2 mm; if the glue layer 2 is SGP, the thickness of the glue layer is in the range of 1.5-2.5 mm.

A device for implementing a method for preparing laminated glass, the device comprises a sheet-joining chamber, a pre-pressing chamber, an autoclave, a coating chamber, and a transfer mechanism, wherein the transfer mechanism is used to transfer a first glass substrate 1 and a second glass substrate 3 into the sheet-joining chamber, transfer a glass substrate that has undergone glue repair into the pre-pressing chamber, transfer a glass substrate that has undergone pre-pressing into the autoclave, and transfer a laminated glass that has undergone final pressing into the coating chamber. The transfer mechanism may be a robot.

Example

The specific steps for preparing laminated glass are as follows:

S1. Cutting out the first glass substrate 1 and the second glass substrate 3 according to the required substrate type, thickness and size, and performing edge processing on the first glass substrate 1 and the second glass substrate 3 as required, including chamfering, rough grinding or fine grinding. The thickness of the first glass substrate 1 and the second glass substrate 3 are both 6 mm;

S2, heat-treating the first glass substrate 1 and the second glass substrate 3 respectively by physical tempering method, when full tempering is performed: the furnace temperature is controlled at 700°C, the glass is uniformly heated to 620°C, then uniformly cooled to 400°C at 11°C/s by a wind pressure of 2800Pa, and then uniformly cooled to room temperature at 11°C/s by a wind pressure of 1000Pa;

S3, setting an adhesive layer between the first glass substrate 1 and the second glass substrate 3 to seal the substrate, wherein the adhesive layer 2 is PVB, the thermal shrinkage rate of the adhesive layer 2 is 1.3%, and the thickness is 1.52 mm;

S4, performing adhesive repair on the first glass substrate and the second glass substrate after lamination, removing the adhesive layer 2 beyond the four sides of the first glass substrate and the second glass substrate, so that the adhesive layer 2 on the four sides of the first glass substrate and the second glass substrate is aligned with the corresponding edges of the first glass substrate and the second glass substrate, and lamination is performed in a constant temperature room with a temperature range of 25° C. and a humidity of 23%.

S5. Pre-press the first glass substrate and the second glass substrate after the glue repair. The glass substrate travel speed is 2 m/min, the pre-pressing heating temperature is 280° C., the roller pressure is 6.5 bar, and after pre-pressing, the furnace temperature is controlled at 60° C.

S6. Move the pre-pressed first glass substrate and the second glass substrate into an autoclave for final pressing to obtain a laminated glass, wherein the autoclave has a holding temperature range of 132° C., a holding pressure range of 12.1 bar, a holding time range of 50 min, and is cooled to 25° C. for exhaust.

Comparative Example

The difference between this example and the embodiment is that it involves two glue repairs.

The specific steps for preparing laminated glass are as follows:

S1. Cutting out the first glass substrate 1 and the second glass substrate 3 according to the required substrate type, thickness and size, and performing edge processing on the first glass substrate 1 and the second glass substrate 3 as required, including chamfering, rough grinding or fine grinding. The thickness of the first glass substrate 1 and the second glass substrate 3 are both 6 mm;

S2, heat-treating the first glass substrate 1 and the second glass substrate 3 respectively by physical tempering method, when full tempering is performed: the furnace temperature is controlled at 700°C, the glass is uniformly heated to 620°C, then uniformly cooled to 400°C at 11°C/s by a wind pressure of 2800Pa, and then uniformly cooled to room temperature at 11°C/s by a wind pressure of 1000Pa;

S3, setting a glue layer between the first glass substrate 1 and the second glass substrate 3 for lamination, wherein the glue layer 2 is PVB, the heat shrinkage rate of the glue layer 2 is 8%, and the thickness is 1.52 mm, wherein a margin of glue layer of about 3 mm beyond the periphery of the glass substrate is reserved;

S4, performing adhesive repair on the first glass substrate and the second glass substrate after lamination, leaving an adhesive layer of 3 mm beyond the first glass substrate and the second glass substrate, and lamination is performed in a constant temperature room with a temperature range of 25° C. and a humidity of 23%;

S5, pre-pressing the first glass substrate and the second glass substrate after the glue repair, the glass substrate travel speed is 1.3m/min, the pre-pressing heating temperature is 240°C, the roller pressure is 6.5bar, and after pre-pressing, the furnace temperature is controlled at 60°C;

S6, moving the pre-pressed first glass substrate and the second glass substrate into an autoclave for final pressing, wherein the autoclave has a holding temperature range of 132° C., a holding pressure range of 12.1 bar, a holding time range of 50 min, and cooling to 25° C. for exhaust;

S7. Perform a second glue repair on the laminated glass after final pressing, remove the glue layer beyond the four sides of the glass, and make the glue layer on the four sides of the glass aligned with the edge of the glass.

The performance test data of laminated glass prepared by the two preparation processes are shown in Table 1:

Table 1 Comparison of performance test data of laminated glass prepared by two preparation processes

As can be seen from Table 1, the laminated glass prepared in the present application has no chipping or peeling at the corners, and the chipping or peeling ratio at the corners is reduced from 90% to 0%; 6 people can be reduced, saving 530,000 yuan in labor costs each year; avoiding interlayer coating discharge and waste of adhesive strips can save 15,000 square meters/year, saving a total of 2.25 million yuan in costs.

Advantages of preparing laminated glass using the laminated glass preparation method provided by the present application: 1) This method only involves one glue repair, which simplifies the process flow, reduces production time, and improves production efficiency; 2) After the glass is pre-pressed and finally pressed, the glue layer between the first glass substrate and the second glass substrate will not overflow to the outer surface of the substrate, and the laminated glass finally prepared will not have chipped corners or peeling, thereby avoiding discharge and waste of glue strips during coating, and greatly improving the quality of laminated glass; 3) Since there is no need to repair the glue after the final pressing, the laminated glass after the final pressing can be directly transferred to the coating chamber, thereby realizing mechanization and automation of laminated glass processing. Since the existing laminated glass preparation involves two glue repairs, the laminated glass after the final pressing needs to be transported to the glue repair room for glue repair during the second glue repair, and the laminated glass after the final pressing cannot be directly transported to the coating chamber. The present method involves one glue repair, and the laminated glass after the final pressing can be directly transported to the coating chamber through a transfer mechanism for coating.

The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims (1)

1. A method for preparing laminated glass, characterized in that it comprises the following steps: S1, cutting to obtain a first glass substrate and a second glass substrate, and pre-treating the first glass substrate and the second glass substrate; S2, heat-treating the pre-treated first glass substrate and the second glass substrate respectively by a physical tempering method; S3, setting a glue layer between the first glass substrate and the second glass substrate for lamination, wherein the thermal shrinkage rate of the glue layer is less than or equal to 1.5%; S4, performing glue repair on the first glass substrate and the second glass substrate after being joined, including: removing the glue layer beyond the four sides of the first glass substrate and the second glass substrate, so that the glue layers on the four sides of the first glass substrate and the second glass substrate are respectively trimmed with the corresponding edges of the first glass substrate and the second glass substrate; S5, pre-pressing the first glass substrate and the second glass substrate after the glue repair by a constant temperature convection process, specifically: placing the first glass substrate and the second glass substrate after the glue repair in a convection roller pressing furnace for convection heating, the convection roller pressing furnace comprising a heating zone and a roller pressing zone arranged in sequence, the heating zone comprising a plurality of convection bellows, two sets of convection bellows are respectively arranged on the left and right sides of the upper part of the first glass substrate and the second glass substrate, and two sets of convection bellows are respectively arranged on the left and right sides of the lower part; S6, moving the pre-pressed first glass substrate and the second glass substrate into an autoclave for final pressing to obtain the laminated glass; In step S2, the heat treatment process is as follows: the furnace temperature is controlled at 680-720° C., the first glass substrate and the second glass substrate are uniformly heated and controlled at 610-630° C., and then quickly and uniformly cooled to room temperature within a preset time threshold range; In step S3, the adhesive layer between the first glass substrate and the second glass substrate is PVB, and the thickness of the adhesive layer is in the range of 1-2 mm; or in step S3, the adhesive layer between the first glass substrate and the second glass substrate is SGP, and the thickness of the adhesive layer is in the range of 1.5-2.5 mm; In step S5, during pre-pressing, the moving speed of the glass substrate is greater than or equal to 1.5 m/min and less than or equal to 3 m/min; In step S5, the heating temperature during pre-pressing is 260°C-300°C; In step S5, after the first glass substrate and the second glass substrate are pre-pressed after the glue repair, the temperature out of the furnace is controlled at 55-75° C.; In step S6, if the adhesive layer between the first glass substrate and the second glass substrate is PVB, the autoclave is kept at a temperature of 130-135° C., a pressure of 12-12.2 bar, and a time of 40-60 min, and is cooled to below 45° C. for exhaust; In step S6, when the adhesive layer between the first glass substrate and the second glass substrate is SGP, the autoclave is kept at a temperature of 135-138°C, a pressure of 12.2-12.5 bar, a time of 90-120 min, and is cooled to below 45°C for exhaust.