INTERLAYER FILM FOR LAMINATED GLASS, ROLL-SHAPED BODY, LAMINATED GLASS, METHOD FOR MANUFACTURING INTERLAYER FILM FOR LAMINATED GLASS, AND METHOD FOR MANUFACTURING ROLL-SHAPED BODY

Abstract

The present invention aims to provide an interlayer film for a laminated glass, which can exhibit high deaeration properties during preliminary pressure bonding and enables production of a highly transparent laminated glass, a roll, a laminated glass, a method for producing the interlayer film for a laminated glass, and a method for producing the roll. The present invention relates to an interlayer film for a laminated glass, having a large number of recesses and a large number of projections on at least one surface, the interlayer film for a laminated glass having a thickness with a difference between a maximum thickness and a minimum thickness of less than 40 m at each of a central portion, one end portion, and an other end portion in a width direction that is orthogonal, in the same plane, to a machine direction of the film in production of the interlayer film for a laminated glass, the thickness being measured along 3 m in the machine direction of the film in production of the interlayer film for a laminated glass at the central portion, the one end portion, and the other end portion in the width direction.

Claims

1. An interlayer film for a laminated glass, having a large number of recesses and a large number of projections on at least one surface, the interlayer film for a laminated glass having a thickness with a difference between a maximum thickness and a minimum thickness of less than 40 m at each of a central portion, one end portion, and an other end portion in a width direction that is orthogonal, on the same plane, to a machine direction of the film in production of the interlayer film for a laminated glass, the thickness being measured along 3 m in the machine direction of the film in production of the interlayer film for a laminated glass at the central portion, the one end portion, and the other end portion in the width direction.

2. The interlayer film for a laminated glass according to claim 1, wherein the interlayer film for a laminated glass has a thickness with a difference between a maximum thickness and a minimum thickness of 30 m or less at each of the central portion, the one end portion, and the other end portion in the width direction that is orthogonal, on the same plane, to the machine direction of the film in production of the interlayer film for a laminated glass, the thickness being measured along 3 m in the machine direction of the film in production of the interlayer film for a laminated glass at the central portion, the one end portion, and the other end portion in the width direction.

3. A roll comprising the interlayer film for a laminated glass according to claim 1 wound up in a machine direction of the film in production of the interlayer film for a laminated glass.

4. 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.

5. A method for producing the interlayer film for a laminated glass according to claim 1, comprising an extrusion step of extruding a raw material resin composition from a die using an extruder, the extruder having a variation in delivery pressure during the extrusion step of 5 kg/cm.sup.2 or less, the die having a variation in temperature during the extrusion step of 20 C. or less.

6. A method for producing the roll according to claim 3, comprising: an extrusion step of extruding a raw material resin composition from a die using an extruder to form an interlayer film for a laminated glass; and a winding step of winding the interlayer film for a laminated glass into a roll in an extrusion direction of the extruded interlayer film for a laminated glass, the extruder having a variation in delivery pressure during the extrusion step of 5 kg/cm.sup.2 or less, the die having a variation in temperature during the extrusion step of 20 C. or less.

7. A roll comprising the interlayer film for a laminated glass according to claim 2 wound up in a machine direction of the film in production of the interlayer film for a laminated glass.

8. A laminated glass comprising: a pair of glass plates; and the interlayer film for a laminated glass according to claim 2 interposed between the pair of glass plates.

9. A method for producing the interlayer film for a laminated glass according to claim 2, comprising an extrusion step of extruding a raw material resin composition from a die using an extruder, the extruder having a variation in delivery pressure during the extrusion step of 5 kg/cm.sup.2 or less, the die having a variation in temperature during the extrusion step of 20 C. or less.

10. A method for producing the roll according to claim 7, comprising: an extrusion step of extruding a raw material resin composition from a die using an extruder to form an interlayer film for a laminated glass; and a winding step of winding the interlayer film for a laminated glass into a roll in an extrusion direction of the extruded interlayer film for a laminated glass, the extruder having a variation in delivery pressure during the extrusion step of 5 kg/cm.sup.2 or less, the die having a variation in temperature during the extrusion step of 20 C. or less.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0073] FIG. 1 is a schematic view for explaining a method for measuring the thickness of an interlayer film for a laminated glass at a central portion, one end portion, and an other end portion in the width direction of the film.

DESCRIPTION OF EMBODIMENTS

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

Example 1

[0075] To 100 parts by mass of a polyvinyl butyral resin (hydroxy group content: 30 mol %, degree of acetylation: 1 mol %, degree of butyralization: 69 mol %, average degree of polymerization: 1700) were added 40 parts by mass of triethylene glycol-di-2-ethylhexanoate (3GO) as a plasticizer, 0.5 parts by mass of 2-(2-hydroxy-3-t-butyl-5-methylphenyl)-5-chlorobenzotriazole (Tinuvin326 produced by Basf SE) as an ultraviolet light shielding agent, and 0.5 parts by mass of 2,6-di-t-butyl-p-cresol (BHT) as an antioxidant, and kneaded with a mixing roll sufficiently to give a resin composition.

[0076] The obtained resin composition was extruded from an extruder to form a single layer interlayer film for a laminated glass having a width of 100 cm. The interlayer film was wound into a roll. At this time, a lip die with a lip interval of 1.2 mm was used. The variation in delivery pressure of the extruder was set to 3 kg/cm.sup.2 or less and the variation in temperature of the die was set to 10 C. or less.

Examples 2 to 8, Comparative Examples 1 to 5

[0077] An interlayer film for a laminated glass was obtained as in Example 1, except that the extrusion conditions were changed within a range that the variation in delivery pressure of the extruder was 5 kg/cm.sup.2 or less and the variation in temperature of the die was 20 C. or less.

Example 9

(Preparation of a Resin Composition for Protective Layers)

[0078] To 100 parts by weight of a polyvinyl butyral resin (a hydroxy group content: 30 mol %, degree of acetylation: 1 mol %, degree of butyralization: 69 mol %, average degree of polymerization: 1700) 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 (Tinuvin326 produced by Basf SE) as an ultraviolet light shielding agent, and 0.5 parts by weight of 2,6-di-t-butyl-p-cresol (BHT) as an antioxidant, and kneaded with a mixing roll sufficiently to give a resin composition for protective layers.

(Preparation of a Resin Composition for Sound Insulation Layers)

[0079] To 100 parts by weight of a polyvinyl butyral resin (hydroxy group content: 23 mol %, degree of acetylation: 12 mol %, degree of butyralization: 65 mol %, average degree of polymerization: 2300) were added 60 parts by weight of triethylene glycol-di-2-ethylhexanoate (3GO) as a plasticizer, and kneaded with a mixing roll sufficiently to give a resin composition for sound insulation layers.

(Production of an Interlayer Film for a Laminated Glass)

[0080] The resin composition for sound insulation layers and the resin composition for protective layers were co-extruded to form an interlayer film for a laminated glass (width: 100 cm) having a triple layer structure including a protective layer (thickness: 350 m), a sound insulation layer (thickness: 100 m), and a protective layer (thickness: 350 m) stacked in said order in the thickness direction. The formed interlayer film for a laminated glass was wound into a roll. At this time, a lip die with a lip interval of 1.2 mm was used. The variation in delivery pressure of the extruder was set to 3 kg/cm.sup.2 or less and the variation in temperature of the die was set to 10 C.

Example 10

[0081] An interlayer film for a laminated glass was obtained as in Example 9, except that the extrusion conditions were changed within a range that the variation in delivery pressure of the extruder was 5 kg/cm.sup.2 or less and the variation in temperature of the die was 20 C. or less.

(Evaluation)

[0082] The interlayer films for a laminated glass obtained in the examples and the comparative examples were evaluated by the following methods.

[0083] Table 1 shows the results.

(1) Evaluation of Variation in Thickness in the Machine Direction of Interlayer Film for a Laminated Glass

[0084] The variation in thickness in the machine direction of the interlayer film for a laminated glass was evaluated by the method shown in FIG. 1.

[0085] First, the interlayer film for a laminated glass was drawn out from the roll and cut at 3 m or longer in the machine direction to give a test sample with a size of 3 m1 m. The obtained test sample was planarly left to stand at 20 C. and 30% RH or less for 24 hours, and the measurement was performed thereon.

[0086] The thickness of the interlayer film for a laminated glass was measured continuously at 1.5 m/min using a micrometer (KG601B-type wide-range electronic micrometer produced by Anritsu Corporation) along the dotted line 41 along the central portion in the width direction and the dotted lines 42 and 43 along the end portions (at a position shifted toward the central portion in the width direction from the edge by a distance corresponding to 5% of the width of the interlayer film for a laminated glass) in the width direction on the test sample after standing. The measurement was performed at 20 C. and 30% RH or less.

[0087] The difference between the maximum thickness and the minimum thickness was calculated for each of the central portion, the one end portion, and the other end portion in the width direction of the interlayer film for a laminated glass based on the obtained data.

(2) Evaluation of Deaeration Properties Upon Preliminary Pressure Bonding

[0088] Six pairs of transparent float glass plates (100 cm in length50 cm in width2 mm in thickness) were prepared. The test sample (size: 3 m1 m) obtained in the evaluation of the variation in thickness in the machine direction was cut into six pieces (size: 1 m0.5 m). The test sample was cut in such a manner that the direction of a 3-m side of the test sample and the direction of a 1-m side of the cut sample piece were in parallel with each other. The resulting six test sample pieces were sandwiched between the six pairs of transparent float glass plates, respectively, thereby preparing six laminates. The obtained laminates were heated in a heating oven until the temperature of the laminates (preliminary pressure bonding temperature) reached 50 C. to 70 C., and transferred between nip rolls (nip pressure by air cylinder: 5 kg/cm.sup.2, linear velocity: 5 m/min), thereby performing preliminary pressure bonding.

[0089] The total light transmittance of the preliminary pressure-bonded laminates was measured with a haze meter (TC-H3DP produced by Tokyo Denshoku Co., Ltd.) in accordance with JIS-K7105. The case where the average total light transmittance of six laminates was 60% or higher was rated Excellent (). The case where the average total light transmittance was 50% or higher but lower than 60% was rated Good (). The case where the average total light transmittance was 40% or higher but lower than 50% was rated Not good (). The case where the average total light transmittance was less than 40% was rated Poor (x).

TABLE-US-00001 TABLE 1 Variation in film thickness Deaeration properties upon in machine direction (m) preliminary pressure bonding End Central End Structure Temperature portion portion portion of film condition Transmittance Example 1 15 23 17 Single layer 50 Example 2 15 23 17 Single layer 70 Example 3 30 22 29 Single layer 50 Example 4 30 22 29 Single layer 70 Example 5 30 29 30 Single layer 50 Example 6 20 18 20 Single layer 70 Example 7 38 31 25 Single layer 50 Example 8 39 27 30 Single layer 70 Example 9 24 19 23 Triple layer 70 Example 10 28 39 30 Triple layer 50 Comparative 42 40 43 Single layer 50 x Example 1 Comparative 42 40 43 Single layer 70 Example 2 Comparative 48 49 51 Single layer 50 x Example 3 Comparative 48 49 51 Single layer 70 x Example 4 Comparative 30 40 50 Single layer 50 Example 5

INDUSTRIAL APPLICABILITY

[0090] The present invention can provide an interlayer film for a laminated glass, which can exhibit high deaeration properties during preliminary pressure bonding and enables production of a highly transparent laminated glass. The present invention also can provide a roll, a method for producing the interlayer film for a laminated glass, and a method for producing the roll.

REFERENCE SIGNS LIST

[0091] 1: Interlayer film for a laminated glass [0092] 2: Roll [0093] 3: Test sample [0094] 41: Dotted line along the central portion in the width direction on the test sample 3 [0095] 42, 43: Dotted line along the end portion in the width direction on the test sample 3