INTERLAYER FOR LAMINATED GLASS, LAMINATED GLASS, AND LAMINATED GLASS SYSTEM

Abstract

The present invention aims to provide an interlayer film for a laminated glass that has a heating layer and a resin layer stacked on the heating layer, generates heat under application of a voltage and warms frozen glass to melt frost or ice, and is capable of preventing occurrence of corrosion. The present invention can also provide a laminated glass produced using the interlayer film for a laminated glass, and a laminated glass system produced using the laminated glass. Provided is an interlayer film for a laminated glass including: a heating layer; and a first resin layer stacked on a first surface side of the heating layer, the heating layer having a metal oxide layer stacked on at least one surface thereof.

Claims

1. An interlayer film for a laminated glass comprising: a heating layer; and a first resin layer stacked on a first surface side of the heating layer, the heating layer having a metal oxide layer stacked on at least one surface thereof.

2. The interlayer film for a laminated glass according to claim 1, wherein the heating layer comprises an alloy containing at least two metals selected from the group consisting of gold, silver, copper, platinum, palladium, titanium, and nickel.

3. The interlayer film for a laminated glass according to claim 1, wherein the heating layer has a surface resistivity of 10/ or lower.

4. The interlayer film for a laminated glass according to claim 1, wherein the metal oxide layer comprises at least one selected from the group consisting of titanium oxide, niobium oxide, silicon oxide, and zinc oxide.

5. The interlayer film for a laminated glass according to claim 4, wherein the metal oxide layer comprises at least one selected from the group consisting of titanium oxide, niobium oxide, and silicon oxide.

6. The interlayer film for a laminated glass according to claim 5, wherein the metal oxide layer comprises titanium oxide or niobium oxide.

7. The interlayer film for a laminated glass according to claim 1, wherein the first resin layer contains a thermoplastic resin.

8. The interlayer film for a laminated glass according to claim 7, wherein the thermoplastic resin is a polyvinyl acetal.

9. The interlayer film for a laminated glass according to claim 1, wherein the first resin layer contains a plasticizer.

10. The interlayer film for a laminated glass according to claim 1, wherein the first resin layer contains an alkali metal salt or an alkaline earth metal salt.

11. The interlayer film for a laminated glass according to claim 1, wherein the first resin layer contains a heat-ray absorbent.

12. The interlayer film for a laminated glass according to claim 1, further comprising a second resin layer stacked on a second surface side, an opposite side of the first surface side, of the heating layer.

13. A laminated glass comprising: a pair of glass plates; and the interlayer film for a laminated glass according to claim 1 interposed between the pair of glass plates.

14. A laminated glass system comprising: the laminated glass according to claim 13; and a voltage supply part for applying a voltage to the heating layer in the interlayer film for a laminated glass of the laminated glass.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0073] FIG. 1 is a schematic view showing an exemplary cross section in the thickness direction of the interlayer film for a laminated glass of the present invention.

DESCRIPTION OF EMBODIMENTS

[0074] Embodiments of the present invention are specifically described in the following with reference to, but not limited to, examples.

Example 1

(1) Preparation of Heating Layer

[0075] A polyethylene terephthalate (PET) film with a thickness of 50 m was used as a substrate. On the substrate was formed a niobium oxide layer with a thickness of 50 nm by sputtering with use of niobium oxide as a target under the conditions of the sputtering power of a 1,000 W direct current (DC), the atmospheric gas of argon, the gas flow rate of 50 sccm, and the sputtering pressure of 0.5 Pa.

[0076] Next, on the niobium oxide layer was formed a silver heating layer with a thickness of 10 nm by sputtering with use of silver as a target under the conditions of the sputtering power of a 1,000 W direct current (DC), the atmospheric gas of argon, the gas flow rate of 50 sccm, and the sputtering pressure of 0.5 Pa.

[0077] Further, on the heating layer was formed a niobium oxide layer with a thickness of 50 nm by sputtering with use of niobium oxide as a target under the conditions of the sputtering power of a 1,000 W direct current (DC), the atmospheric gas of argon, the gas flow rate of 50 sccm, and the sputtering pressure of 0.5 Pa.

(2) Preparation of Resin Layer

[0078] To 100 parts by weight of polyvinyl butyral (hydroxy group content of 30 mol %, degree of acetylation of 1 mol %, degree of butyralization of 69 mol %, average degree of polymerization of 1,700) were added 40 parts by weight of triethylene glycol di-2-ethylhexanoate (3GO) as a plasticizer, 0.5 parts by weight of 2-(2-hydroxy-3-t-butyl-5-methylphenyl)-5-chlorobenzotriazole (Tinuvin 326 available from BASF SE) as a UV blocking agent, and 0.5 parts by weight of 2,6-di-t-butyl-p-cresol (BHT) as an antioxidant. They were sufficiently kneaded with a mixing roll to prepare a composition. The obtained composition was extruded from an extruder to provide a single-layer resin film of polyvinyl butyral (PVB) with a thickness of 380 m.

(3) Production of Interlayer Film for a Laminated Glass

[0079] Two sheets of the resin film were prepared, and a substrate on which a heating layer and niobium oxide layers were formed was sandwiched between the two resin films. The laminate was thermal compression bonded to produce an interlayer film for a laminated glass having a laminated structure (first resin layer/niobium oxide layer/heating layer/niobium oxide layer/substrate/second resin layer). The thermal compression bonding was performed by a roll-to-roll method using a thermal compression bonding laminator (MRK-650Y type available from MCK Co., Ltd.) under the conditions of a heating temperature of 75 C., a bonding pressure of 1.0 kN, and a feed tension of 20 N. Laminating rolls used for the thermal compression bonding had upper and lower rolls both formed of rubber.

Examples 2 and 3

[0080] Interlayer films for a laminated glass were produced in the same manner as in Example 1, except that niobium oxide was changed to titanium oxide or silicon oxide.

Examples 4 to 6

[0081] Interlayer films for a laminated glass were produced respectively in the same manner as in Examples 1 to 3, except that sputtering was performed with use of APC (silver-palladium-copper alloy), in place of Ag, as a target to form an APC heating layer with a thickness of 10 nm and the thickness of the metal oxide layer was changed.

Comparative Examples 1 and 2

[0082] Interlayer films for a laminated glass were produced respectively in the same manner as in Examples 1 and 4, except that the metal oxide layer was not formed.

Example 7

[0083] The substrate used was a polyethylene terephthalate (PET) film with a thickness of 50 m. On the substrate was formed a titanium oxide layer with a thickness of 80 nm by sputtering with use of titanium dioxide (TiO.sub.2) as a target under the conditions of the sputtering power of a 1,000 W direct current (DC), the atmospheric gas of argon, the gas flow rate of 50 sccm, and the sputtering pressure of 0.5 Pa.

[0084] Next, on the titanium oxide layer was formed a silver heating layer with a thickness of 25 nm by sputtering with use of silver as a target under the conditions of the sputtering power of a 1,000 W direct current (DC), the atmospheric gas of argon, the gas flow rate of 50 sccm, and the sputtering pressure of 0.5 Pa.

[0085] Further, on the heating layer was formed a titanium oxide layer with a thickness of 80 nm by sputtering with use of titanium dioxide (TiO.sub.2) as a target under the conditions of the sputtering power of a 1,000 W direct current (DC), the atmospheric gas of argon, the gas flow rate of 50 sccm, and the sputtering pressure of 0.5 Pa.

[0086] An interlayer film for a laminated glass having a laminated structure (first resin layer/titanium oxide layer/heating layer/titanium oxide layer/substrate/second resin layer) was produced in the same manner as in Example 1, except that the obtained substrate with a titanium oxide layer, a heating layer, and a titanium oxide layer formed thereon was used.

(Evaluation)

[0087] The interlayer films for a laminated glass obtained in the examples and comparative examples were evaluated by the following methods.

[0088] Table 1 shows the results.

(1) Evaluation of Heat Generation Properties (Temperature Attained by Heat Generation, Planar Heat Generation Properties and High-Temperature Heat Generation Properties)

[0089] To each end of the obtained laminated glass was attached a single-sided copper foil tape STS-CU42S (Sekisui Techno Shoji Nishi Nihon Co., Ltd.) as an electrode. A DC 12 V/4.2 A power source (S8JX-N05012DC available from OMRON Corporation) and the electrodes were connected using an alligator cable.

[0090] A 12 V voltage was applied to the laminated glass at 25 C. for seven minutes. The temperature (surface temperature) attained by heat generation at a central portion of the laminated glass surface after the seven minutes voltage application was measured using a contact-type thermometer. Here, the temperature attained by heat generation of X C. refers to a temperature increase of X C. on the basis of 25 C. before application of a voltage. For example, when the temperature attained by heat generation is 20 C., the temperature of the laminated glass is 45 C. Further, the difference in the surface temperature between the vicinity of an end portion (1 cm inside the end portion) and the central portion of the laminated glass was obtained. The planar heat generation properties and high-temperature heat generation properties were evaluated based on the following criteria.

[Evaluation Criteria of Planar Heat Generation Properties and High-Temperature Heat Generation Properties]

[0091] (Good): The temperature increased uniformly throughout from the vicinity of the end portion to the central portion of the laminated glass (difference in temperature between the vicinity of the end portion and the central portion after the temperature increase was 4 C. or lower) and the temperature attained by heat generation was 20 C. or higher.
(Average): The temperature increased uniformly throughout from the vicinity of the end portion to the central portion of the laminated glass (difference in temperature between the vicinity of the end portion and the central portion after the temperature increase was 4 C. or lower) and the temperature attained by heat generation was lower than 20 C.
x (Poor): The temperature did not increase or the temperature increase was not uniform between the end portion and the central portion of the laminated glass (difference in temperature between the vicinity of the end portion and the central portion after the temperature increase was higher than 4 C.)

(2) Evaluation of Occurrence of Corrosion

[0092] The obtained interlayer film for a laminated glass was cut into a piece of 30 cm in length30 cm in width. Separately, two clear glass plates (30 cm in length30 cm in width2.5 mm in thickness) were prepared. The obtained interlayer film piece was sandwiched between the two clear glass plates, and held in a vacuum laminator at 90 C. for 30 minutes to be vacuum pressed. Thus, a laminate was obtained. The interlayer film part protruding from the glass plates of the laminate was cut, thereby preparing a laminated glass. The obtained laminated glass was subjected to evaluation of corrosion using a thermohygrostat oven (ESPEC Corp.) under the conditions of 80 C. and 90% RH.

[0093] The obtained laminated glass was placed in the oven, and its appearance after a lapse of every predetermined time period was visually checked. In this evaluation, the interlayer film for a laminated glass was observed a day later, 7 days later, and 14 days later.

(Good): No defective appearance (no spot-like pattern due to agglomeration)
x (Poor): Defective appearance (spot-like pattern due to agglomeration present)

TABLE-US-00001 TABLE 1 Exam- Exam- Exam- Exam- Exam- Exam- Exam- Comparative Comparative ple 1 ple 2 ple 3 ple 4 ple 5 ple 6 ple 7 Example 1 Example 2 Interlayer film First resin layer PVB PVB PVB PVB PVB PVB PVB PVB PVB for a laminated Metal Type Nb.sub.2O.sub.5 TiO.sub.2 SiO.sub.2 Nb.sub.2O.sub.5 TiO.sub.2 SiO.sub.2 TiO.sub.2 glass oxide layer Thickness (nm) 50 50 50 70 70 70 80 Heating Type Ag Ag Ag APC APC APC Ag Ag APC layer Thickness (nm) 10 10 10 10 10 10 25 10 10 Metal Type Nb.sub.2O.sub.5 TiO.sub.2 SiO.sub.2 Nb.sub.2O.sub.5 TiO.sub.2 SiO.sub.2 TiO.sub.2 oxide layer Thickness (nm) 50 50 50 70 70 70 80 Substrate PET PET PET PET PET PET PET PET PET Second resin layer PVB PVB PVB PVB PVB PVB PVB PVB PVB Evaluation Heat generation properties Corrosion 1 day later x x 7 days later x x 14 days later x x

INDUSTRIAL APPLICABILITY

[0094] The present invention can provide an interlayer film for a laminated glass that has a heating layer and a resin layer stacked on the heating layer, generates heat under application of a voltage and warms frozen glass to melt frost or ice, and is capable of preventing occurrence of corrosion. The present invention can also provide a laminated glass produced using the interlayer film for a laminated glass, and a laminated glass system produced using the laminated glass.

REFERENCE SIGNS LIST

[0095] 1 Interlayer film for a laminated glass [0096] 2 Heating layer [0097] 3 Substrate [0098] 4 Metal oxide layer [0099] 5 First resin layer [0100] 6 Second resin layer