Fire-protection and safety composite glass panel

Abstract: A fire protective glass panel for use in a fire protective window, door, and partition wall, which comprises at least one sheet of fireproof glass plate 21 and a fluorocarbon resin film 31 of a chain molecular structure type bonded to a face of the glass plate and which has non-shattering property as well as fire protection property. The fireproof glass plate is a heat-resistant and light transparent crystallized glass plate. Alternatively, the fireproof glass plate is a wire glass plate. The fluorocarbon resin film has a thickness of 0.02-1 mm and is made of one of FEP, PFA, PCTFE, ETFE, and PVDF.

Description: Background of the Invention: The present invention relates to a glass panel for fire protection and, in particular, to such a glass panel having nonshattering property as well as fire resistant or fireproof property. In order to prevent the spreading of fire, a door, a window, or a partition wall are made of fire resistant or fire proof materials, for example, iron or steel. However, iron and steel are not light transparent and are, therefore, not desired for the window. Further, the door and the partition are often desired to be made of light transparent materials. As a glass material for use in fire protection doors, windows, partitions and other fire protection structures, a fireproof or fire resistant glass plate is known in the art. A typical fireproof glass plate is a wire glass which is a sheet glass with woven wire mesh embedded in the center of the sheet. Another type of fireproof glass plate is made of a heat-resistant and light transparent crystallized glass plate. An example of such crystallized glass plate is, "Fire Lite" glass plate which is made by Nippon Electric Glass Company Limited, a corporation in Japan, and is available in commerce. The crystallized glass consists of 3-5 wt.% Li 2 O, 20-35 wt.% Al 2 O 3 , 55-70 wt.% SiO 2 , 1-3 wt.% TiO 2 , 1-4 wt.% ZrO 2 , 1-5 wt.% P 2 O 5 , 0-4 wt.% Na 2 O, and 0-4 wt.% K 2 O, with the total amount of Na 2 O and K 2 O being 0.5 -4 wt.%. The crystallized glass contains beta-quartz or beta-eucriptite solid solution crystals. The crystallized glass is disclosed as a heat resistant glass in U.S. Patent No. 3,282,712. The crystallized glass plate has been tested according to the Notification No. 1125 of the Ministry of Construction of Japan and allowed to be used as a fireproof glass for use in a fire protective door, window, partition and other fire protections. A conventional soda glass plate is low in mechanical impact resistance and in thermal shock. Therefore, it is readily broken and shattered by such impact or shock. Safety glass is also known in the art which is improved in mechnical strength and has nonshattering property. As typical safety glasses, there are known laminated glass and glass covered with a thin plastic film. However, these safety glasses have no fire protection US-A-3 373 076 describes transparent glass laminates having improved performances up to temperatures of about 177°C and comprising an amorphous high molecular weight chlorotrifluoroethylene-tetrafluoroethylene-vinylidene fluoride terpolymer. Although the wire glass is effective as a safety glass, it tends to broken by a certain strength of mechanical impact to form a through hole. Therefore, wire glass is not acceptable as safety glass. Summary of the Invention: Therefore, it is an object of the present invention to provide a fire protection glass panel which has excellent resistance and mechanical strength. According to the present invention, a fire-protection and safety composite glass panel is obtained which comprises a fireproof glass plate with opposed faces and a layer of fluorocarbon resin film of a chain molecular structure type bonded on one of the opposed faces. The panel preferably comprises another layer of the fluorocarbon resin film bonded on the other face. The fireproof glass plate is made of a heat-resistant and light transparent crystallized glass, or alternatively, a wire glass. The crystallized glass preferably consists of 3-5 wt.% Li 2 O, 20-35 wt.% Al 2 O 3 , 55-70 wt.% SiO 2 , 1-3 wt.% TiO 2 , 1-4 wt.% ZrO 2 , 1-5 wt.%, P 2 O 5 , 0-4 wt.% Na 2 O and 0-4 wt.% K 2 O, the total amount of Na 2 O and K 2 O being 0.5-4 wt.% said crystallized glass containing beta-quartz solid solution crystals. The fluorocarbon resin film is preferably made of one of fluorinated ethylene propylene (FEP), tetrafluoroethylene perfluoroalkoxyl ethylene copolymer (PFA), polychlorotrifluoroethylene (PCFE), ethylene tetrafluoroethylene copolymer (ETFE), and polyvinyliden fluoride (PVDF). The fluorocarbon resin film preferably has a thickness of 0.02-1 mm. According to another aspect of the present invention, a fire-protection and safety composite glass panel is obtained which comprises a plurality of glass plates laminated with a layer of fluorocarbon resin film of the chain molecular structure type between adjacent glass plates. At least one of the glass plates is a fireproof glass plate. According to further aspects of the present invention, a fire protective window is obtained which comprises window glass in accordance with the above first aspect and a sash for the window glass. According to a still further aspect of the present invention there is provided a fume protective door comprising a glass panel and a frame for the glass panel, wherein the glass panel is a composite glass panel in accordance with the above first aspect. Brief Description of the Drawings: Figs. 1 to 9 and 10 are cross-sectional views of samples in examples of Nos. 1 to 9 and 10; Figs. 11 to 13 and 14 are cross-sectional views of samples in comparative examples of Nos. 1 to 3 and 4; Fig. 15 is a view illustrating impact resistant test of samples; Fig. 16 is a front view of a fire-protective window using the composite glass panel according to the present invention; and Fig. 17 is a perspective view of a fire-protective door using the composite glass panel according to the present invention. Description of the Invention: Briefly speaking, the present invention attempts to provide the safety or nonshattering property to a fireproof or fire-resistant glass plate by laminating a layer of the fluorocarbon resin film of a chain molecular structure type thereto. The fluorocarbon resin of the chain molecular structure type has a unit structure represented by the following: where X, X′, and X'' are one of H, Cl, F, -CF3, -O-CF2-CF2-CF3, and the like. Because of a strong interatomic binding of such as C-C and C-F, and of a barrier effect of F atoms covering the carbon chain, the fluorocarbon resin is incombustible. The fluorocarbon resin is known to be excellent in chemical stability, heat resistance, wear resistance, light transparency, and mechanical properties such as extension and tensile strength. The fluorocarbon resin film can be joined onto a surface of the fireproof or fire resistant glass plate by the thermo compression bonding or by use of adhesive agent. Even if a combustible adhesive is used, it is covered with the incombustible fluorocarbon resin film and it is prevented from firing. When the fluorocarbon film is melted by the further heating, the molten fluorocarbon resin encloses the adhesive so that the adhesive is also prevented from firing. The resultant composite glass plate has the fluorocarbone resin film laminated onto the glass plate and is provided with the nonshattering property and excellent impact absorption without reduction of incombustibility, light transparence, chemical stability and others. Therefore, the composite glass panel is useful for fire protective windows, doors, partitions and others. Further, it is provided with high mechanical strength and nonshattering property and is, therefore, useful as a safety or nonshattering glass plate for windows, doors, and other partition walls. As several examples of the fluorocarbone resin of the chain molecular structure type, there are known, as typical ones, fluorinated ethylene propylene (FEP), tetrafluoroethylene perfluoroalkoxyl ethylene copolymer (PFA), polychlorotrifluoroethylene (PCFE), ethylene tetrafluoroethylene copolymer (ETFE), and polyvinylidene fluoride (PVDF). The fluorocarbon resin film used in the present invention can have a desired thickness but preferably, of 0.02-1 mm thickness. Now, description will be made as to examples of the present invention and comparative examples. Example 1 Referring to Fig. 1, a sheet of "Fire Lite" glass plate 21, that is a heat-resistant light transparent crystallized glass plate, was prepared with a dimension of 2000x900x5 mm. A PFA film 31 with a thickness of 50 µm was bonded onto one side surface of the glass sheet or plate 21 to form a sample of a composite glass panel. The bonding war performed by the thermo compression bonding with pressure of 12 Kg/cm 2 at a temperature of 330 o C. Example 2 Referring to Fig. 2, an FEP film 32 with a thickness of 100 µm was bonded by a silicone adhesive agent onto one surface of the glass plate 21 similar to that in Example 1 to form a sample of the composite glass panel. Example 3 Referring to Fig. 3, a sheet of "Fire Lite" glass plate 21 was prepared with a dimension of 2000x900x8 mm. Two sheets of PFA film 31 with a thickness of 50 µm were bonded by use of acrylic adhesive onto both side surfaces of the glass plate 21 to form a sample of a composite glass panel. Example 4 Two "Fire Lite" glass plates 21 similar to that in Fig. 1 were prepared. Referring to Fig. 4, a film 32 of FEP with a thickness of 125 µm was held between those two glass plates 21 and was bonded thereto to form a sample of the composite glass panel. The bonding was performed by the thermo compression bonding by a pressure of 12 Kg/cm 2 at a temperature 280 o C. Example 5 The "Fire Lite" glass plate 21 similar to that in Example 1 and a sheet of conventional soda glass plate 22 with a dimension of 2000x900x3 mm were prepared. Referring to Fig. 5, a film 31 of PFA with a thickness of 150 µm was held between the glass plates 21 and 22 and was bonded thereto to form a sample of the composite galss panel. The bonding was performed by the thermo compression bonding by a pressure of 12 Kg/cm 2 at a temperature 330 o C. Example 6 The "Fire Lite" glass plate 21 similar to that in Example 1 and two sheets of soda glass plate 22 with a dimension of 2000x900x6 mm were prepared. Referring to Fig. 6, the "Fire Lite" glass plate 21 was interposed between two soda glass plates 22 and 22. Two films 32 of FEP with a thickness of 200 µm were held between the glass plates 22 and 21 and between glass plates 21 and 22. Then, those three glass plates were bonded through those FEP films 32 to form a laminated glass panel as a sample of the composite glass panel. The bonding was performed by the thermo compression bonding by a pressure of 12 Kg/cm 2 at a temperature 280 o C. Example 7 A piece of wire glass plate 23 with a dimension of 1900x900x6.8 mm was cut from a wire glass plate which was available in commerce. Referring to Fig. 7, a film 31 of PFA with a thickness of 50 µm was bonded onto one side surface of the wire glass plate piece 23. The bonding was performed by the thermo compression bonding by a pressure of 12 Kg/cm 2 at a temperature 330 o C. Example 8 Referring to Fig. 8, a film 32 of FEP with a thickness of 100 µm was bonded by use of a silicone adhesive agent onto one side surface of the wire glass plate piece 23 similar to that in Example 7 to form a sample of a composite glass panel according to the present invention. Example 9 Referring to Fig. 9, a film 32 of FEP with a thickness of 125 µm was held between two pieces of wire glass plate 23 similar to that in Example 7 and was bonded thereto under pressure of 12 Kg/cm 2 , at a temperature of 280 o C. Thus, a sample of the composite glass panel was produced. Example 10 Referring to Fig. 10, a film 31 of PFA with a thickness of 150 µm was held between a wire glass piece 23 similar to that in Example 7 and a soda glass piece 22 with a dimension of 1900x900x5 mm and was bonded thereto under a pressure of 12 Kg/cm 2 at a temperature of 330 o C. Thus, a smaple of the composite glass panel. Comparative Example 1 Two pieces of soda glass plate 22 were cut out with a dimension of 2000x900x5 mm. Referring to Fig. 11, a film 33 of polyvinyl butyral (PVB) with a thickness of 1 mm was held between the soda glass plate pieces 22 and was bonded thereto under a pressure of 12 Kg/cm 2 at a temperature of 170 o C thus, a comparative sample was produced. Comparative Example 2 Referring to Fig. 12, a PVB film 33 with a thickness of 1 mm was held between a "Fire Lite" glass plate piece 21 similar to that in Example 1 and a soda glass plate piece 22 of a dimension of 2000x900x3 mm and was bonded thereto under a pressure of 12 Kg/cm 2 at a temperature of 170 o C. Thus, a comparative sample was produced. Comparative Example 3 Referring to Fig. 13, a PFA film 31 with a thickness of 50 µm was bonded onto a side surface of a soda glass plate piece 22 under a pressure of 12 Kg/cm 2 at a temperature of 330 o C. Thus, a comparative sample was produced. Comparative Example 4 Referring to Fig 14, a PVB film 33 with a thickness of 1 mm was held between a wire glass plate piece similar to that in Example 7 and a soda glass plate piece 22 with a dimension of 1900x900x5 mm and was bonded under a pressure of 12 Kg/cm 2 at a teperature of 170 o C. Thus, a comparative sample was produced. These samples and comparative samples were subjected to the following impact-resistant, firing, smoking, and fire-resistant tests. Now, the impact-resistant test will be described. Referring to Fig. 15, one of those samples and comparative samples in the above-described Examples and Comparative Examples is disposed as a test piece S at a predetermined position of an iron frame 41. The iron frame 41 has a hook 42 on its top to which an end of a wire 43 is connected while a weight 44 being connected to the other end of the wire 43. The weight has a mass of 45 Kg. The distance from the hook 42 to the centre of the weight 44 is adjusted to 1524 mm. The weight 44 and the wire 43 are turned about the hook 42 so that the weight 44 is brought up at a level H higher than a free position. Then, the weight 44 is freed and collides with the test piece S. The collision is repeated with gradual increase of the level H one by one. The impact resistant factor of the test piece S is represented by the maximum level H max of the weight which cannot make a through hole in the test piece but makes a total amount of broken and fallen glass fragments 50 grams or less. The firing and the smoking tests are carried out by heating a test piece in a gas heating furnace according to the standard heating curve by the Notification No. 1125 of the Ministry of Construction of Japan. The test piece is observed as regards whether or not the test piece smokes and fires. The fire-resistant test is carried out by heating one side surface of the test piece by a gas firing flame according to the standard heating curve and observing whether or not a through hole is made in the test piece and whether or not the flame blows to an opposite side surface of the test piece. The time duration from start of heating to occurrence of any one of those phenomena represents the fire-resistant factor of the test piece. Table 1 shows a result of those tests for the samples and comparative samples in the above-described Examples 1-10 and Comparative Examples 1-4. According to the test result shown in Table 1, the samples in Examples 1-10 by the present invention are excellent in the impact resistance and do neither fire nor smoke. Further, the samples of Examples 1-6 have a fire resistance of 180 minutes or more and samples of Examples 7-10 have a fire resistance of 20 minutes or more. However, the samples of Comparative Examples 1-4 have a degraded fire resistance although they are excellent in the impact resistance. In the comparative sample 1, both of soda glass plate pieces 22 thermally cracked to form a through hole about 8 minutes after the start of heating. In the comparative sample 2, a soda glass plate piece 22 at a nonheated side thermally cracked and fell off about 6 minutes after start of heating and then the PVB film 33 was evaporated and fired. In the comparative sample 3, the soda glass plate piece 22 thermally cracked about three minutes and fell off about six minutes after start of heating. In the comparative sample 4, the soda glass plate piece 22 at the nonheated side thermally cracked after start of heating and the PVB film was evaporated and fired about five minutes after start of heating. Referring to Fig. 16, a window is shown which comprises a glass plate 51 and a sash 52 for the glass plate 51. The composite glass panel according to the present invention is used for the glass plate so that the window is a fire protective and safety window. Referring to Fig 17, a fire protection and safety door is also shown which comprises a glass plate 61 made of the composite glass panel and a door frame 62. The door is installed in an opening 63.

Claims: A fire-protection and safety composite glass panel comprising a fireproof glass plate with opposed faces and a layer of fluorocarbon resin film of a chain molecular structure type bonded on one of said opposed faces. A composite glass panel as claimed in claim 1, which further comprises another layer of said fluorocarbon resin film bonded on the other face. A fire-protection and safety composite glass panel comprising a plurality of glass plates laminated with a layer of fluorocarbon resin film of a chain molecular structure type between adjacent glass plates, at least one of said glass plates being a fireproof glass plate. A composite glass panel as claimed in claim 1, claim 2 or claim 3 wherein said fireproof glass plate is made of a heat-resistant and light transparent crystallized glass. A composite glass panel as claimed in claim 4, wherein said crystallized glass consists of 3-5 wt.% Li 2 O, 20-35 wt.% Al 2 O 3 , 55-70 wt.% SiO 2 , 1-3 wt.% TiO 2 , 1-4 wt.% ZrO 2 , 1-5 wt.% P 2 O 5 , 0-4 wt.% Na 2 O, and 0-4 wt.% K 2 O, the total amount of Na 2 O and K 2 O being 0.5 -4 wt.%, said crystallized glass containing beta-quartz solid solution crystals. A composite glass panel as claimed in any one of claims 1 to 5 wherein said fireproof glass plate is made of a wire glass. A composite glass panel as claimed in any one of claims 1 to 6 wherein said fluorocarbon resin film is made of one of fluorinated ethylene propylene (FEP), tetrafluoroethylene perfluoroalkoxyl ethylene copolymer (PFA), polychlorotrifluoroethylene (PCFE), ethylene tetrafluoroethylene copolymer (ETFE), and polyvinylidene fluoride (PVDF). A composite glass panel as claimed in any one of claims 1 to 7 wherein said fluorocarbon resin film has a thickness of 0.02-1 mm. A fire protective window comprising a window glass, and a sash for said window glass, said window glass comprising a composite glass panel as claimed in any one of claims 1 to 8. A fire protective door comprising a glass panel and a frame for said glass panel, said glass panel comprising a composite glass panel as claimed in any one of claims 1 to 8.

Inventors: KATAGI KIYOSHI, SAKAMOTO AKIHIKO, SHIBUYA TAKEHIRO, KATAGI, KIYOSHI, SAKAMOTO, AKIHIKO, SHIBUYA, TAKEHIRO
Applicants: NIPPON ELECTRIC GLASS CO, NIPPON ELECTRIC GLASS COMPANY, LIMITED
Application year: 1991
Main classification: B32B17
IPC codes: B32B17, C03C10, C03C17