Interlayer for laminated glass, laminated glass, and production method for interlayer for laminated glass

Abstract

The present invention provides an interlayer film for a laminated glass which is easily peelable without autohesion even after storage in a stacked state, a laminated glass prepared using the interlayer film for a laminated glass, and a method for producing the interlayer film for a laminated glass. The present invention provides an interlayer film for a laminated glass, having a large number of recesses on at least one surface, the at least one surface having the recesses having an arithmetical mean height Sa of 200 nm or more as measured in conformity with ISO 25178.

Claims

1. An interlayer film for a laminated glass, having a plurality of recesses on at least one surface, the at least one surface having the recesses has an arithmetical mean height Sa of 200 nm or more and 3,000 nm or less as measured in conformity with ISO 25178.

2. The interlayer film for a laminated glass according to claim 1, wherein the at least one surface having the recesses has an arithmetical mean height Sa of 250 nm or more and 3,000 nm or less as measured in conformity with ISO 25178.

3. The interlayer film for a laminated glass according to claim 1, wherein the plurality of recesses on the at least one surface each have a groove shape with a continuous bottom.

4. The interlayer film for a laminated glass according to claim 3, wherein the recesses each having a groove shape with a continuous bottom are regularly adjacent and parallel to each other.

5. The interlayer film for a laminated glass according to claim 3, further having a plurality of protrusions on the at least one surface having the recesses, wherein the surface has an arithmetical mean height Sa of 200 nm or more as measured for apexes of the protrusions in conformity with ISO 25178.

6. The interlayer film for a laminated glass according to claim 3, having a plurality of recesses on both surfaces, wherein the recesses on both surfaces each have a groove shape with a continuous bottom, and an intersection angle between the recesses each having a groove shape with a continuous bottom on one surface and the recesses each having a groove shape with a continuous bottom on the other surface is 10 or more.

7. The interlayer film for a laminated glass according to claim 3, further having a plurality of protrusions on each surface having the recesses, wherein the protrusions have a radius of rotation R of 200 m or less.

8. The interlayer film for a laminated glass according to claim 1, wherein each surface having the recesses has a ten-point average roughness Rz of 10 m or more as measured in conformity with JIS B 0601 (1994).

9. 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.

10. An interlayer film for a laminated glass, having a plurality of recesses and a plurality of protrusions on at least one surface, the plurality of recesses each having a groove shape with a continuous bottom, the at least one surface having the recesses has an arithmetical mean height Sa of 200 nm or more and 3,000 nm or less as measured in conformity with ISO 25178, and the at least one surface has an arithmetical mean height Sa of 200 nm or more as measured for apexes of the protrusions in conformity with ISO 25178.

11. A laminated glass comprising: a pair of glass plates; and the interlayer film for a laminated glass according to claim 10 interposed between the pair of glass plates.

12. A method for producing the interlayer film for a laminated glass according to claim 1, the method comprising the step of: forming a plurality of recesses on at least one surface of the interlayer film for a laminated glass by an embossing roll method using an embossing roll produced by a production process, the production process including: an embossing roll production step 1 of forming protrusions and recesses on a metal roll by blasting with an abrasive material, an embossing roll production step 2 of grinding a portion of each protrusion on the metal roll having the protrusions and recesses into a flat surface portion, and an embossing roll production step 3 of forming protrusions and recesses on the metal roll by blasting with an abrasive material finer than the abrasive material used in the embossing roll production step 1.

13. The method for producing the interlayer film for a laminated glass according to claim 12, wherein the abrasive material to be used in the embossing roll production step 3 has a grain diameter at a cumulative height of 3% in conformity with JIS R6001 (1998) of 150 m or less, and a grain diameter at a cumulative height of 94% in conformity with JIS R6001 (1998) of 11 m or more.

14. A method for producing the interlayer film for a laminated glass according to claim 1, the method being intended to form a plurality of recesses on at least one surface of the interlayer film for a laminated glass by an embossing method in which melt fracture phenomena are controlled, the method comprising the steps of: extruding a resin composition for forming an interlayer film for a laminated glass from a die; and cooling the extruded interlayer film for a laminated glass in a cooling water tank, a distance between the die and the cooling water tank being adjusted to 250 mm or less in the cooling.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIG. 1 shows a schematic view of an exemplary interlayer film for a laminated glass, having recesses on a surface, in which the recesses each having a groove shape with a continuous bottom are adjacent and parallel to each other at equal intervals.

(2) FIG. 2 shows a schematic view of an exemplary interlayer film for a laminated glass, having recesses on a surface, in which the recesses each having a groove shape with a continuous bottom are adjacent and parallel to each other at equal intervals.

(3) FIG. 3 shows a schematic view of an exemplary interlayer film for a laminated glass, having recesses on a surface, in which the recesses each having a groove shape with a continuous bottom are adjacent and parallel to each other at unequal intervals.

(4) FIG. 4 shows a schematic view of an exemplary interlayer film for a laminated glass, having a blockish pattern on a surface.

(5) FIG. 5 shows a schematic view of an exemplary interlayer film for a laminated glass, having a spherical pattern on a surface.

(6) FIG. 6 shows schematic views explaining an interval Sm between recesses and a radius of rotation R of a protrusion.

(7) FIG. 7 shows a schematic view explaining an intersection angle .

DESCRIPTION OF EMBODIMENTS

(8) Embodiments of the present invention are more specifically described in the following with reference to, but not limited to, examples.

Example 1

(9) (1) Preparation of a Resin Composition

(10) Polyvinyl alcohol having an average degree of polymerization of 1,700 was acetalized with n-butyraldehyde to give polyvinyl butyral (acetyl group content: 1 mol %, butyral group content: 69.1 mol %, hydroxy group content: 30 mol %). To 100 parts by mass of the polyvinyl butyral was added 40 parts by mass of triethylene glycol-di-2-ethylhexanoate (3GO) as a plasticizer, and kneaded well with a mixing roll to give a resin composition.

(11) (2) Production of an Interlayer Film for a Laminated Glass

(12) The obtained resin composition was extruded from an extruder into an interlayer film for a laminated glass having a uniform thickness.

(13) (3) Formation of First Shape

(14) In accordance with Production Example 1, the first shape was formed on both surfaces (a first surface and a second surface) of the interlayer film for a laminated glass.

(15) Here, an embossing roll produced by the following method was used.

(16) First, in the embossing roll production step 1, a surface of the metal roll was blasted with an abrasive material (#36) made of aluminum oxide at a discharge pressure of 5010.sup.4 Pa. The surface of the roll after the embossing roll production step 1 had a ten-point average roughness Rz of 65 m as measured in conformity with JIS B 0601 (1994).

(17) Next, in the embossing roll production step 2, partial grinding was performed with a grinding stone (#400 to 1000). The surface of the roll after the embossing roll production step 1 had a ten-point average roughness Rz of 40 m as measured in conformity with JIS B 0601 (1994).

(18) Next, in the embossing roll production step 3, blasting was performed with an abrasive material (#320) made of aluminum oxide at a discharge pressure of 5010.sup.4 Pa.

(19) The obtained embossing rolls were paired up and used as a device for transferring a pattern of protrusions and recesses to form the first shape on both surfaces of the obtained interlayer film for a laminated glass. The transferring conditions were adjusted as follows to obtain desired roughness: a temperature of the interlayer film for a laminated glass of 80 C., a temperature of the rolls of 145 C., a linear velocity of 10 m/min, a line width of 1.5 m, and a linear pressure of 1 to 100 kN/m. The obtained interlayer film for a laminated glass had a thickness of 760 m.

(20) (4) Measurement of Protrusions and Recesses on a First Surface and a Second Surface

(21) (4-1) Sa Value Measurement

(22) The surface of the interlayer film for a laminated glass was measured using a three-dimensional white light interference microscope (ContourGT-K available from Bruker AXS GmbH) in a 1 mm square field of view at an objective lens magnification of 115 times, an internal lens magnification of 0.5 times, and a resolution set to Full resolution to obtain images. The obtained images were subjected to planarization and noise removal processes, and further subjected to Maskdata process to extract data on the heights of only the protrusions. Coarse protrusions and recesses were removed from the extracted data region using a Gaussian filter, and the arithmetical mean height Sa was calculated by the method specified in ISO 25178. Analytical software Vision64 included in the apparatus was used in image processing. Conditions for the planarization and noise removal processes involved performing the first processing Terms Removal (F-Operator) on Analysis Toolbox under the analysis condition Tilt only (Plane Fit), performing the second processing Statistic Filter under the analysis conditions Filter type: Sigma and Filter size: 5, and further performing the processing data Restore by selecting the analysis condition Legacy, selecting Restore Edge condition, and setting Iteration condition to a value for sufficient data complement. In the third step Mask data to extract image data on only the protrusions, the Height threshold of a histogram displayed under the analysis condition Histogram Mask was determined to be between 0.2 and 0.2 m, and data on height regions equal to or more than the threshold was extracted under the condition Mask: Left. In order to remove coarse protrusions and recesses, the fourth processing Gaussian Regression Filter was performed under the analysis conditions Short wavelength pass, order: 2, Type: Regular, and Long wavelength cutoff: 0.025 mm, and advance setup was performed under initial conditions. The image data after the first processing through the third processing was subjected to the fourth processing S parameters-height under the analysis condition Removal tilt: True. The resulting Sa was used as the arithmetical mean height Sa value. Nine points in a 10 cm square of the interlayer film for a laminated glass were measured such that these points were 3 cm or more distant from each other. The average of the measurement values is used as the Sa value.

(23) (4-2) Rz Value Measurement

(24) The ten-point average roughness (Rz) on both surfaces of the obtained interlayer film was measured by the method in conformity with JIS B-0601 (1994). The measuring instrument used was Surfcorder SE300 available from Kosaka Laboratory Ltd. The measurement was performed using a stylus profilometer at a cut-off value of 2.5 mm, a standard length of 2.5 mm, an evaluation length of 12.5 mm, and a measurement rate of 0.5 mm/s, with a stylus having a tip radius of 2 m and a tip angle of 60. The stylus was moved in a direction parallel to the direction of sheet flow.

Examples 2 and 3 and Comparative Examples 1 and 2

(25) An interlayer film for a laminated glass was produced in the same manner as in Example 1 except the followings: a different type of the blasting agent was used in the embossing roll production step 3 to produce an embossing roll for forming the first shape; and the pressure of the press for transferring a pattern of protrusions and recesses was adjusted to obtain a desired Rz value. Then, the protrusions and recesses on both surfaces of the interlayer film were measured.

Example 4

(26) (1) Preparation of a Resin Composition

(27) Polyvinyl alcohol having an average degree of polymerization of 1,700 was acetalized with n-butyraldehyde to give polyvinyl butyral (acetyl group content: 1 mol %, butyral group content: 69.1 mol %, hydroxy group content: 30 mol %). To 100 parts by mass of the polyvinyl butyral were added 40 parts by mass of triethylene glycol-di-2-ethylhexanoate (3GO) as a plasticizer, and kneaded well with a mixing roll to give a resin composition.

(28) (2) Production of an Interlayer Film for a Laminated Glass

(29) The obtained resin composition was extruded from an extruder into an interlayer film for a laminated glass having a uniform thickness.

(30) (3) Formation of First Shape

(31) The first shape was formed on a surface of the interlayer film for a laminated glass by the same method as in Example 3.

(32) (4) Formation of Second Shape

(33) Protrusions and recesses each having a groove shape with a continuous bottom were formed by the following procedure on the interlayer film for a laminated glass on which the first shape was formed. A pair of rolls including a metal roll having a surface milled with a triangular oblique line-type mill and a rubber roll having a JIS hardness of 45 to 75 was used as a device for transferring a pattern of protrusions and recesses. The interlayer film for a laminated glass having the first shape was passed through the device for transferring a pattern of protrusions and recesses, thereby forming protrusions and recesses on a first surface of the interlayer film for a laminated glass. The recesses each having a groove shape with a continuous bottom were parallel to each other at equal intervals. The transferring conditions employed here were a temperature of the interlayer film for a laminated glass of 70 C., a temperature of the rolls of 140 C., a linear velocity of 10 m/min, and a linear pressure of 1 to 100 kN/m. Then, the same operation was performed on a second surface of the interlayer film for a laminated glass to form recesses each having a groove shape with a continuous bottom. Here, the intersection angle between the recesses each having a groove shape with a continuous bottom (shape of an engraved line) formed on the first surface and the recesses each having a groove shape with a continuous bottom (shape of an engraved line) formed on the second surface was adjusted to 20. The obtained interlayer film for a laminated glass had a thickness of 760 m.

(34) (5) Measurement of Protrusions and Recesses on First Surface and Second Surface after Formation of Second Shape

(35) (5-1) Sa Value Measurement

(36) The surface of the interlayer film for a laminated glass was measured using a three-dimensional white light interference microscope (ContourGT-K available from Bruker AXS GmbH) in a 1 mm square field of view at an objective lens magnification of 115 times, an internal lens magnification of 0.5 times, and a resolution set to Full resolution to obtain images. The surface of the interlayer film for a laminated glass was measured using a three-dimensional white light interference microscope (ContourGT-K available from Bruker AXS GmbH) in a 1 mm square field of view at an objective lens magnification of 115 times, an internal lens magnification of 0.5 times, and a resolution set to Full resolution to obtain images. The obtained images were subjected to planarization and noise removal processes. Data on the heights of only the protrusions was further extracted by the Mask data processing. Coarse protrusions and recesses were removed from the extracted data region using a Gaussian filter. Then, the arithmetical mean height Sa value was calculated by a method specified by ISO 25178. Analytical software Vision64 included in the apparatus was used in image processing. Conditions for the planarization and noise removal processes involved performing the first processing Terms Removal (F-Operator) on Analysis Toolbox under the analysis condition Tilt only (Plane Fit), performing the second processing Statistic Filter under the analysis conditions Filter type: Sigma and Filter size: 5, and further performing the processing data Restore by selecting the analysis condition Legacy, selecting Restore Edge condition, and setting Iteration condition to a value for sufficient data complement. In the third step Mask data to extract image data on only the protrusions, the Height threshold of a histogram displayed under the analysis condition Histogram Mask is determined to be between 0.2 and 0.2 m, and data on height regions equal to or more than the threshold is extracted under the condition Mask: Left. In order to remove coarse protrusions and recesses, the fourth processing Gaussian Regression Filter was performed under the analysis conditions Short wavelength pass, order: 2, Type: Regular, and Long wavelength cutoff: 0.025 mm, and advance setup was performed under initial conditions. The image data after the first processing through the third processing was subjected to the fourth processing S parameters-height under the analysis condition Removal tilt: True. The resulting Sa was used as the arithmetical mean height Sa value.

(37) Nine points in a 10 cm square of the interlayer film for a laminated glass were measured such that these points were 3 cm or more distant from each other. The average of the measurement values was used as the Sa value.

(38) (5-2) Apex Sa Value Measurement

(39) The surface of the interlayer film for a laminated glass was measured using a three-dimensional white light interference microscope (ContourGT-K available from Bruker AXS GmbH) in a 1 mm square field of view at an objective lens magnification of 115 times, an internal lens magnification of 0.5 times, and a resolution set to Full resolution to obtain images. Analytical software Vision64 included in the apparatus was used in image processing. Conditions for the planarization and noise removal processes involve performing the first processing Terms Removal (F-Operator) on Analysis Toolbox under the analysis condition Tilt only (Plane Fit), performing the second processing Statistic Filter under the analysis conditions Filter type: Sigma and Filter size: 5, and further performing the processing data Restore by selecting the analysis condition Legacy, selecting Restore Edge condition, and setting Iteration condition to a value for sufficient data complement. In the third step Mask data to extract image data on only the protrusions, the Height threshold of a histogram displayed under the analysis condition Histogram Mask was determined to be between 0.2 and 0.2 m, and data on height regions equal to or more than the threshold is extracted under the condition Mask: Left. In order to remove coarse protrusions and recesses, the fourth processing Gaussian Regression Filter was performed under the analysis conditions Short wavelength pass, order: 2, Type: Regular, and Long wavelength cutoff: 0.025 mm, and advance setup was performed under initial conditions. The image data after the first processing through the third processing was subjected to the fourth processing S parameters-height under the analysis condition Removal tilt: True. The resulting Sa was used as the arithmetical mean height Sa value. Nine points in a 10 cm square of the interlayer film for a laminated glass were measured such that these points were 3 cm or more distant from each other. The average of the measurement values was used as the Sa value.

(40) (5-3) Rz Value Measurement

(41) The ten-point average roughness (Rz) on both surfaces of the obtained interlayer film was measured by the method in conformity with JIS B 0601 (1994). The measurement instrument used was Surfcorder SE300 available from Kosaka Laboratory Ltd. The measurement was performed using a stylus profilometer at a cut-off value of 2.5 mm, a standard length of 2.5 mm, an evaluation length of 12.5 mm, and a measurement rate of 0.5 mm/s, with a stylus having a tip radius of 2 m and a tip angle of 60. The measurement environment was 23 C. and 30 RH %. The stylus was moved in a direction perpendicular to the direction of the grooves in the shape of engraved lines.

(42) (5-4) Sm Measurement

(43) An optical microscope (e.g., DSX-100 available from Olympus Corporation) was used to observe the first surface and the second surface of the obtained interlayer film for a laminated glass (observation range: 4 mm4 mm), and the interval between adjacent recesses was measured for every pair of adjacent recesses. Then, the shortest distances between deepest bottoms of adjacent recesses were averaged to determine the interval Sm of the recesses.

(44) (5-5) Measurement of Radius of Rotation R of Protrusion

(45) The interlayer film was cut in a direction perpendicular to the recesses in the shape of engraved lines and in the film thickness direction. The cross section was observed using a microscope (e.g., DSX-100 available from Olympus Corporation) and photographed at a magnification of 277 times. The obtained image was enlarged to 50/20 mm. In this state, the radius of an inscribed circle at the apex of a protrusion shape was determined as the radius of rotation of the tip of the protrusion, using measurement software included in accessory software. Thus, the radius of rotation R of the protrusion was measured. The measurement environment was 23 C. and 30 RH %.

Examples 5 to 8

(46) An interlayer film for a laminated glass was produced in the same manner as in Example 4 except the followings: a different type of the fine blasting agent as shown in Table 1 was used in the embossing roll production step 3 to produce an embossing roll for forming the first shape; the embossing shape and the pitch width for forming the second shape were changed as shown in Table 1; and the linear pressure for forming the second shape was adjusted to 1 to 100 kN/m to obtain desired roughness. Then, the protrusions and recesses on both surfaces of the interlayer film were measured.

(47) (Evaluation)

(48) The interlayer films for a laminated glass obtained in Examples 1 to 8 and Comparative Examples 1 and 2 were evaluated for autohesion by the following method. Table 1 shows the results.

(49) The interlayer film for a laminated glass obtained in each of the examples and comparative examples was cut into a size of 150 mm in length and 150 mm in width to obtain a test specimen. Two test specimens thus obtained were stacked, and a glass plate (weight: 5.8 kg) was placed thereon with a release paper as a means of releasing treatment interposed therebetween. The release paper was prepared by silicone coating of a base paper. In this state, the test specimens were left for 48 hours in a constant temperature and humidity bath adjusted to a temperature of 30 C. and a humidity of 30%. Then, 2 cm end portions of the two test specimens were peeled from each other, and the end portions of the two test specimens were fixed with 15 cm wide grippers, respectively. The 180 peel strength between the two test specimens was measured in conformity with JIS K-6854-3 (1999) at a peel rate of 50 cm/min in an environment of a temperature of 23 C. and a humidity of 30%, and the average peel strength (N/15 cm) of a peeling distance from 50 mm to 200 mm was calculated. The other conditions conformed to JIS K-6854-3 (1994). The obtained value was used as the autohesion force of the interlayer film for a laminated glass.

(50) For peeling by a machine transporting interlayer films for a laminated glass or by human power, the autohesion force is preferably 20 N/15 cm or less, more preferably 13 N/15 cm or less, still more preferably 10 N/15 cm or less.

(51) TABLE-US-00001 TABLE 1 Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Composition of Polyvinyl Average degree of 1700 1700 1700 1700 1700 1700 interlayer film butyral resin polymerization of PVA Butyralation degree 69 69 69 69 69 69 (mol %) Acetylation degree 1 1 1 1 1 1 (mol %) Hydroxy group content 30 30 30 30 30 30 (mol %) Amount (parts by mass) 100 100 100 100 100 100 Plasticizer Type 3GO 3GO 3GO 3GO 3GO 3GO Amount (parts by mass) 40 40 40 40 40 40 First shape Formation Fine blast size (mesh) #320 #320 #320 #320 #320 #320 method (Production Example 1) Pattern of Sa (nm) 490 467 284 284 284 284 protrusions Rz (m) 24 21 15 15 15 15 and recesses on first surface Pattern of Sa (nm) 520 460 286 286 286 286 protrusions Rz (m) 23 21 16 16 16 16 and recesses on second surface Second shape Formation Embossing type (shape) Engraved Engraved Engraved method lines lines lines Pattern of Sa (nm) 223 220 240 protrusions Apex Sa (nm) 265 266 265 and recesses Rz (m) 40 33 35 on first Sm (m) 300 180 184 surface Radius of rotation R (m) 60 55 55 Pattern of Sa (nm) 221 208 251 protrusions Apex Sa (nm) 255 269 274 and recesses Rz (m) 40 33 34 on second Sm (m) 300 175 180 surface Radius of rotation R (m) 60 55 58 Intersection angle () between 20 20 10 engraved lines Evaluation Autohesion (N/15 cm) 5.8 7.6 17.0 14.5 12.8 15.2 Comparative Comparative Example 7 Example 8 Example 1 Example 2 Composition of Polyvinyl Average degree of 1700 1700 1700 1700 interlayer film butyral resin polymerization of PVA Butyralation degree 69 69 69 69 (mol %) Acetylation degree 1 1 1 1 (mol %) Hydroxy group content 30 30 30 30 (mol %) Amount (parts by mass) 100 100 100 100 Plasticizer Type 3GO 3GO 3GO 3GO Amount (parts by mass) 40 40 40 40 First shape Formation Fine blast size (mesh) #320 #320 #320 #800 method (Production Example 1) Pattern of Sa (nm) 284 284 170 172 protrusions Rz (m) 15 15 9 22 and recesses on first surface Pattern of Sa (nm) 286 286 168 181 protrusions Rz (m) 16 16 10 18 and recesses on second surface Second shape Formation Embossing type (shape) Engraved Engraved method lines lines Pattern of Sa (nm) 211 202 protrusions Apex Sa (nm) 265 266 and recesses Rz (m) 33 33 on first Sm (m) 183 190 surface Radius of rotation R (m) 54 57 Pattern of Sa (nm) 216 240 protrusions Apex Sa (nm) 269 260 and recesses Rz (m) 33 30 on second Sm (m) 181 177 surface Radius of rotation R (m) 58 55 Intersection angle () between 45 90 engraved lines Evaluation Autohesion (N/15 cm) 9.8 8.0 52.0 28.0

Example 9

(52) (1) Preparation of a Resin Composition

(53) Polyvinyl alcohol having an average degree of polymerization of 1,700 was acetalized with n-butyraldehyde to give polyvinyl butyral (acetyl group content: 1 mol %, butyral group content: 69.1 mol %, hydroxy group content: 30 mol %). To 100 parts by mass of the polyvinyl butyral were added 40 parts by mass of triethylene glycol-di-2-ethylhexanoate (3GO) as a plasticizer, and kneaded well with a mixing roll to give a resin composition.

(54) (2) Production of an Interlayer Film for a Laminated Glass and Formation of First Shape

(55) While an interlayer film for a laminated glass was formed, the first shape was also formed in conformity with Production Example 2.

(56) Specifically, while an interlayer film for a laminated glass was formed, the first shape was also formed in conformity with the embossing method in which melt fracture phenomena are controlled, under the following conditions: an extrusion amount per die width of 440 kg/hr.Math.m, a temperature of the film surface immediately after being extruded from the die of 200 C., a resin pressure at the die inlet of 80 kgf/cm.sup.2, and a water temperature in the water tank for cooling the film of 20 C. to 30 C. Here, the distance between the die and the surface of the cooling water tank was 50 mm.

(57) The obtained interlayer film for a laminated glass had a thickness of 760 m. The Sa value and the Rz value were measured by the same methods as in Example 1.

Examples 10 and 11 and Comparative Example 3

(58) An interlayer film for a laminated glass was produced in the same manner as in Example 9, except that the distance between the die and the surface of the cooling water tank for forming the first shape was changed as shown in Table 2, and the protrusions and recesses on both surfaces of the interlayer film were measured.

Example 12

(59) (1) Preparation of a Resin Composition

(60) Polyvinyl alcohol having an average degree of polymerization of 1,700 was acetalized with n-butyraldehyde to give polyvinyl butyral (acetyl group content: 1 mol %, butyral group content: 69.1 mol %, hydroxy group content: 30 mol %). To 100 parts by mass of the polyvinyl butyral were added 40 parts by mass of triethylene glycol-di-2-ethylhexanoate (3GO) as a plasticizer, and kneaded well with a mixing roll to give a resin composition.

(61) (2) Production of an Interlayer Film for a Laminated Glass and Formation of First Shape

(62) While an interlayer film for a laminated glass was formed, the first shape was also formed in conformity with Production Example 2.

(63) An interlayer film for a laminated glass was produced in the same manner as in Example 9, except that the distance between the die and the surface of the cooling water tank was changed as shown in Table 2, and the first shape was formed on both surfaces of the interlayer film.

(64) The obtained interlayer film for a laminated glass had a thickness of 760 m. The Sa value and the Rz value were measured by the same methods as in Example 1.

(65) (3) Formation of Second Shape

(66) Protrusions and recesses each having a groove shape with a continuous bottom were formed by the following procedure on the interlayer film for a laminated glass on which the first shape was formed. A pair of rolls including a metal roll having a surface milled with a triangular oblique line-type mill and a rubber roll having a JIS hardness of 45 to 75 was used as a device for transferring a pattern of protrusions and recesses. The interlayer film for a laminated glass having the first shape was passed through the device for transferring a pattern of protrusions and recesses, thereby forming protrusions and recesses on a first surface of the interlayer film for a laminated glass. The recesses each having a groove shape with a continuous bottom were parallel to each other at equal intervals. The transferring conditions employed here were a temperature of the interlayer film for a laminated glass of 70 C., a temperature of the rolls of 140 C., a linear velocity of 10 m/min, and a linear pressure of 1 to 100 kN/m. Then, the same operation was performed on a second surface of the interlayer film for a laminated glass to form recesses each having a groove shape with a continuous bottom. Here, the intersection angle between the recesses each having a groove shape with a continuous bottom (shape of an engraved line) formed on the first surface and the recesses each having a groove shape with a continuous bottom (shape of an engraved line) formed on the second surface was adjusted to 20.

(67) After the formation of the second shape, the protrusions and recesses on the first surface and the second surface were measured by the same method as in Example 4.

Examples 13 to 16 and Comparative Examples 4 to 6

(68) An interlayer film for a laminated glass was produced in the same manner as in Example 12 except the followings: the distance between the die and the surface of the cooling water tank for forming the first shape was changed as shown in Table 2; the embossing shape and the pitch width for forming the second shape were changed as shown in Table 2; and the linear pressure for forming the second shape was adjusted to 1 to 100 kN/m to obtain desired roughness. Then, the protrusions and recesses on both surfaces of the interlayer film were measured.

(69) (Evaluation)

(70) The interlayer films for a laminated glass obtained in Examples 9 to 16 and Comparative Examples 3 to 6 were evaluated for autohesion by the same method as in Example 1. Table 2 shows the results.

(71) TABLE-US-00002 TABLE 2 Example 9 Example 10 Example 11 Example 12 Example 13 Example 14 Composition of Polyvinyl Average degree of 1700 1700 1700 1700 1700 1700 interlayer film butyral resin polymerization of PVA Butyralation degree 69 69 69 69 69 69 (mol %) Acetylation degree 1 1 1 1 1 1 (mol %) Hydroxy group content 30 30 30 30 30 30 (mol %) Amount (parts by mass) 100 100 100 100 100 100 Plasticizer Type 3GO 3GO 3GO 3GO 3GO 3GO Amount (parts by mass) 40 40 40 40 40 40 First shape Formation Distance between die and 50 100 200 100 50 200 method water surface (mm) (Production Example 2) Pattern of Sa (nm) 553 350 267 350 553 260 protrusions Rz (m) 30 22 23 22 30 17 and recesses on first surface Pattern of Sa (nm) 440 382 277 382 553 259 protrusions Rz (m) 29 20 20 20 30 18 and recesses on second surface Second shape Formation Embossing type (shape) Engraved Engraved Engraved method lines lines lines Pattern of Sa (nm) 302 400 208 protrusions Apex Sa (nm) 340 517 244 and recesses Rz (m) 42 42 40 on first Sm (m) 200 200 200 surface Tip R (m) 62 65 70 Pattern of Sa (nm) 303 404 200 protrusions Apex Sa (nm) 375 501 244 and recesses Rz (m) 44 44 44 on second Sm (m) 200 200 200 surface Tip R (m) 61 65 68 Intersection angle () between 20 20 90 engraved lines Evaluation Autohesion (N/15 cm) 7.8 11.0 16.0 8.5 5.7 6.0 Comparative Comparative Comparative Comparative Example 15 Example 16 Example 3 Example 4 Example 5 Example 6 Composition of Polyvinyl Average degree of 1700 1700 1700 1700 1700 1700 interiayer film butyral resin polymerization of PVA Butyralation degree 69 69 69 69 69 69 (mol %) Acetylation degree 1 1 1 1 1 1 (mol %) Hydroxy group content 30 30 30 30 30 30 (mol %) Amount (parts by mass) 100 100 100 100 100 100 Plasticizer Type 3GO 3GO 3GO 3GO 3GO 3GO Amount (parts by mass) 40 40 40 40 40 40 First shape Formation Distance between die and 200 50 300 300 300 300 method water surface (mm) (Production Example 2) Pattern of Sa (nm) 260 543 145 145 145 145 protrusions Rz (m) 17 17 20 20 20 20 and recesses on first surface Pattern of Sa (nm) 259 560 136 136 136 136 protrusions Rz (m) 18 21 20 20 20 20 and recesses on second surface Second shape Formation Embossing type (shape) Spherical Blockish Engraved Spherical Blockish method lines Pattern of Sa (nm) 220 452 110 130 138 protrusions Apex Sa (nm) 222 540 138 132 136 and recesses Rz (m) 33 38 40 33 38 on first Sm (m) 500 500 200 500 500 surface Tip R (m) 88 Pattern of Sa (nm) 274 458 136 133 133 protrusions Apex Sa (nm) 250 582 134 133 138 and recesses Rz (m) 34 40 44 34 40 on second Sm (m) 499 501 204 499 501 surface Tip R (m) 80 Intersection angle () between 90 90 engraved lines Evaluation Autohesion (N/15 cm) 6.7 4.0 30.0 23.3 24.1 23.7

Examples 17 and 18

(72) An interlayer film for a laminated glass was produced in the same manner as in Example 1 except the followings: polyvinyl butyral having a composition as shown in Table 3 was used; a different type of the blasting agent was used in the embossing roll production step 3 to produce an embossing roll for forming the first shape; and the pressure of the press for transferring a pattern of protrusions and recesses was adjusted to obtain a desired Rz value. Then, the protrusions and recesses on both surfaces of the interlayer film were measured.

Examples 19 to 21

(73) An interlayer film for a laminated glass was produced in the same manner as in Example 4 except the followings: polyvinyl butyral having a composition as shown in Table 3 was used; a different type of the fine blasting agent as shown in Table 3 was used in the embossing roll production step 3 to produce an embossing roll for forming the first shape; the embossing shape and the pitch width for forming the second shape were changed as shown in Table 3; and the linear pressure for forming the second shape was adjusted to 1 to 100 kN/m to obtain desired roughness. Then, the protrusions and recesses on both surfaces of the interlayer film were measured.

(74) (Evaluation)

(75) The interlayer films for a laminated glass obtained in Examples 17 to 21 were evaluated for autohesion by the same method as in Example 1. Table 3 shows the results.

(76) TABLE-US-00003 TABLE 3 Example 17 Example 18 Example 19 Example 20 Example 21 Composition of Polyvinyl Average degree of 1700 1700 1700 1700 1700 interlayer film butyral resin polymerization of PVA Butyralation degree 69.9 68.4 68.4 69.9 68.4 (mol %) Acetylation degree 1.2 0.7 0.7 1.2 0.7 (mol %) Hydroxy group content 29 30.9 30.9 29 30.9 (mol %) Amount (parts by mass) 100 100 100 100 100 Plasticizer Type 3GO 3GO 3GO 3GO 3GO Amount (parts by mass) 40 40 40 40 40 First shape Formation Fine blast size (mesh) #320 #320 #320 #320 #320 method (Production Example 1) Pattern of Sa (nm) 490 501 501 290 285 protrusions Rz (m) 24 25 25 16 16 and recesses on first surface Pattern of Sa (nm) 520 519 519 294 288 protrusions Rz (m) 23 22 22 16 16 and recesses on second surface Second shape Formation Embossing type (shape) Engraved Engraved Engraved method lines lines lines Pattern of Sa (nm) 450 243 245 protrusions Apex Sa (nm) 500 270 266 and recesses Rz (m) 35 39 38 on first Sm (m) 195 200 198 surface Radius of rotation R (m) 50 60 55 Pattern of Sa (nm) 440 221 240 protrusions Apex Sa (nm) 503 255 261 and recesses Rz (m) 35 40 38 on second Sm (m) 180 199 198 surface Radius of rotation R (m) 50 60 50 Intersection angle () between 20 90 90 engraved lines Evaluation Autohesion (N/15 cm) 5.8 5.9 5.0 7.5 7.3

Examples 22 and 23

(77) An interlayer film for a laminated glass was produced in the same manner as in Example 9 except the followings: polyvinyl butyral having a composition as shown in Table 4 was used; and the distance between the die and the surface of the cooling water tank for forming the first shape was changed as shown in Table 4. Then, the protrusions and recesses on both surfaces of the interlayer film were measured.

Example 24

(78) An interlayer film for a laminated glass was produced in the same manner as in Example 12 except the followings: polyvinyl butyral having a composition as shown in Table 4 was used; the distance between the die and the surface of the cooling water tank for forming the first shape was changed as shown in Table 4; the embossing shape and the pitch width for forming the second shape were changed as shown in Table 4; and the linear pressure for forming the second shape was adjusted to 1 to 100 kN/m to obtain desired roughness. Then, the protrusions and recesses on both surfaces of the interlayer film were measured.

(79) (Evaluation)

(80) The interlayer films for a laminated glass obtained in Examples 22 to 24 were evaluated for autohesion by the same method as in Example 1. Table 4 shows the results.

(81) TABLE-US-00004 TABLE 4 Example 22 Example 23 Example 24 Composition of Polyvinyl Average degree of 1700 1700 1700 interlayer film butyral resin polymerization of PVA Butyralation degree 69.9 68.4 69.9 (mol %) Acetylation degree 1.2 0.7 1.2 (mol %) Hydroxy group content 29 30.9 29 (mol %) Amount (parts by mass) 100 100 100 Plasticizer Type 3GO 3GO 3GO Amount (parts by mass) 40 40 40 First shape Formation Distance between die and 50 50 200 method water surface (mm) (Production Example 2) Pattern of Sa (nm) 553 588 260 protrusions Rz (m) 37 40 17 and recesses on first surface Pattern of Sa (nm) 483 570 259 protrusions Rz (m) 38 42 18 and recesses on second surface Second shape Formation Embossing type (shape) Engraved lines method Pattern of Sa (nm) 208 protrusions Apex Sa (nm) 244 and recesses Rz (m) 40 on first Sm (m) 200 surface Tip R (m) 70 Pattern of Sa (nm) 200 protrusions Apex Sa (nm) 244 and recesses Rz (m) 44 on second Sm (m) 200 surface Tip R (m) 68 Intersection angle () between 90 engraved lines Evaluation Autohesion (N/15 cm) 7.5 7.0 6.0

Example 25

(82) (Preparation of a Resin Composition for a Protective Layer)

(83) Polyvinyl alcohol having an average degree of polymerization of 1,700 was acetalized with n-butyraldehyde to give polyvinyl butyral (acetyl group content: 1 mol %, butyral group content: 69 mol %, hydroxy group content: 30 mol %). To 100 parts by mass of the polyvinyl butyral were added 36 parts by mass of triethylene glycol-di-2-ethylhexanoate (3GO) as a plasticizer, and kneaded well with a mixing roll to give a resin composition for protective layers.

(84) (Preparation of a Resin Composition for an Intermediate Layer)

(85) Polyvinyl alcohol having an average degree of polymerization of 3,000 was acetalized with n-butyraldehyde to give polyvinyl butyral (acetyl group content: 12.5 mol %, butyral group content: 64.2 mol %, hydroxy group content: 23.3 mol %). To 100 parts by mass of the polyvinyl butyral were added 76.5 parts by mass of triethylene glycol-di-2-ethylhexanoate (3GO) as a plasticizer, and kneaded well with a mixing roll to give a resin composition for intermediate layers.

(86) (Production of an Interlayer Film for a Laminated Glass)

(87) The obtained resin composition for intermediate layers and resin composition for protective layers were co-extruded using a co-extruder to form an interlayer film for a laminated glass having a triple layer structure including a first protective layer made of the resin composition for protective layers, an intermediate layer made of the resin composition for intermediate layers, and a second protective layer made of the resin composition for protective layers, stacked in the stated order. The extrusion conditions were set such that the first and second protective layers each had a thickness of 350 m and the intermediate layer had a thickness of 100 m in an interlayer film for a laminated glass to be obtained after formation of protrusions and recesses.

(88) Subsequently, protrusions and recesses were formed on an interlayer film for a laminated glass in the same manner as in Example 1 except the followings: a different type of the blasting agent was used in the embossing roll production step 3 to produce an embossing roll for forming the first shape; and the pressure of the press for transferring a pattern of protrusions and recesses was adjusted to obtain a desired Rz value. Then, the protrusions and recesses on both surfaces of the interlayer film were measured.

Example 26 and Comparative Examples 7 and 8

(89) An interlayer film for a laminated glass was produced in the same manner as in Example 25 except the followings: a different type of the blasting agent was used in the embossing roll production step 3 to produce an embossing roll for forming the first shape; and the pressure of the press for transferring a pattern of protrusions and recesses was adjusted to obtain a desired Rz value. Then, the protrusions and recesses on both surfaces of the interlayer film were measured.

Example 27

(90) An interlayer film for a laminated glass was produced and the first shape was formed thereon in the same manner as in Example 25 except the followings: a different type of the blasting agent was used in the embossing roll production step 3 to produce an embossing roll for forming the first shape; and the pressure of the press for transferring a pattern of protrusions and recesses was adjusted to obtain a desired Rz value.

(91) Protrusions and recesses each having a groove shape with a continuous bottom were formed by the following procedure on the interlayer film for a laminated glass on which the first shape was formed. A pair of rolls including a metal roll having a surface milled with a triangular oblique line-type mill and a rubber roll having a JIS hardness of 45 to 75 was used as a device for transferring a pattern of protrusions and recesses. The interlayer film for a laminated glass having the first shape was passed through the device for transferring a pattern of protrusions and recesses, thereby forming protrusions and recesses on a first surface of the interlayer film for a laminated glass. The recesses each having a groove shape with a continuous bottom were parallel to each other at equal intervals. The transferring conditions employed here were a temperature of the interlayer film for a laminated glass of 70 C., a temperature of the rolls of 140 C., a linear velocity of 10 m/min, and a linear pressure of 1 to 100 kN/m. Then, the same operation was performed on a second surface of the interlayer film for a laminated glass to form recesses each having a groove shape with a continuous bottom. Here, the intersection angle between the recesses each having a groove shape with a continuous bottom (shape of an engraved line) formed on the first surface and the recesses each having a groove shape with a continuous bottom (shape of an engraved line) formed on the second surface was adjusted to 20.

Examples 28 to 33 and Comparative Example 9

(92) An interlayer film for a laminated glass was produced in the same manner as in Example 27 except the followings: polyvinyl butyral having a composition as shown in Table 6 or 7 was used; a different type of the fine blasting agent as shown in Table 6 or 7 was used in the embossing roll production step 3 to produce an embossing roll for forming the first shape; the embossing shape and the pitch width for forming the second shape were changed as shown in Table 6 or 7; and the linear pressure for forming the second shape was adjusted to 1 to 100 kN/m to obtain desired roughness. Then, the protrusions and recesses on both surfaces of the interlayer film were measured.

(93) (Evaluation)

(94) The interlayer films for a laminated glass obtained in Examples 25 to 33 and Comparative Examples 7 to 9 were evaluated for autohesion by the same method as in Example 1. Tables 5 to 7 show the results.

(95) TABLE-US-00005 TABLE 5 Example 25 Example 26 Example 27 Example 28 First and Polyvinyl Average degree of 1700 1700 1700 1700 second butyral resin polymerization of PVA protective Butyralation degree 69 69 69 69 layers (mol %) Acetylation degree 1 1 1 1 (mol %) Hydroxy group content 30 30 30 30 (mol %) Amount (parts by mass) 100 100 100 100 Plasticizer Type 3GO 3GO 3GO 3GO Amount (parts by mass) 36 36 36 36 Structure Thickness (m) 350 350 350 350 Intermediate Polyvinyl Average degree of 3000 3000 3000 3000 layer butyral resin polymerization of PVA Butyralation degree 64.2 64.2 64.2 64.2 (mol %) Acetylation degree 12.5 12.5 12.5 12.5 (mol %) Hydroxy group content 23.3 23.3 23.3 23.3 (mol %) Amount (parts by mass) 100 100 100 100 Plasticizer Type 3GO 3GO 3GO 3GO Amount (parts by mass) 76.5 76.5 76.5 76.5 Structure Thickness (m) 100 100 100 100 Interlayer Structure Arrangement First protective First protective First protective First protective film as a layer/ layer/ layer/ layer/ whole Intermediate Intermediate Intermediate Intermediate layer/ layer/ layer/ layer/ Second Second Second Second protective layer protective layer protective layer protective layer Thickness (m) 800 800 800 800 First shape Formation Fine blast size (mesh) #320 #320 #320 #320 method (Production Example 1) Pattern of Sa (nm) 480 450 290 290 protrusions Rz (m) 23 20 16 16 and recesses on first surface Pattern of Sa (nm) 511 455 280 280 protrusions Rz (m) 23 20 16 16 and recesses on second surface Second Formation Embossing type (shape) Engraved lines Engraved lines shape method Pattern of Sa (nm) 222 219 protrusions Apex Sa (nm) 270 270 and recesses Rz (m) 41 34 on first Sm (m) 299 182 surface Radius of rotation R (m) 70 54 Pattern of Sa (nm) 220 210 protrusions Apex Sa (nm) 260 270 and recesses Rz (m) 40 34 on second Sm (m) 299 178 surface Radius of rotation R (m) 70 56 Intersection angle () between 20 20 engraved lines Evaluation Autohesion (N/15 cm) 5.7 7.4 14.3 12.9

(96) TABLE-US-00006 TABLE 6 Example 29 Example 30 Example 31 Example 32 First and Polyvinyl Average degree of 1700 1700 1700 1700 second butyral resin polymerization of PVA protective Butyralation degree 69 69 69 69.9 layers (mol %) Acetylation degree 1 1 1 1.1 (mol %) Hydroxy group content 30 30 30 29 (mol %) Amount (parts by mass) 100 100 100 100 Plasticizer Type 3GO 3GO 3GO 3GO Amount (parts by mass) 36 36 36 39 Structure Thickness (m) 350 350 350 350 Intermediate Polyvinyl Average degree of 3000 2300 1700 2300 layer butyral resin polymerization of PVA Butyralation degree 64.2 64.2 64.2 77.8 (mol %) Acetylation degree 12.5 12.5 12.5 1.5 (mol %) Hydroxy group content 23.3 23.3 23.3 20.7 (mol %) Amount (parts by mass) 100 100 100 100 Plasticizer Type 3GO 3GO 3GO 3GO Amount (parts by mass) 76.5 76.5 76.5 79 Structure Thickness (m) 100 100 100 100 Interlayer Structure Arrangement First protective First protective First protective First protective film as a layer/ layer/ layer/ layer/ whole Intermediate Intermediate Intermediate Intermediate layer/ layer/ layer/ layer/ Second Second Second Second protective layer protective layer protective layer protective layer Thickness (m) 800 800 800 800 First shape Formation Fine blast size (mesh) #320 #320 #320 #320 method (Production Example 1) Pattern of Sa (nm) 290 289 300 280 protrusions Rz (m) 16 15 16 16 and recesses on first surface Pattern of Sa (nm) 280 300 310 285 protrusions Rz (m) 16 17 17 16 and recesses on second surface Second Formation Embossing type (shape) Engraved lines Engraved lines Engraved lines Engraved lines shape method Pattern of Sa(nm) 205 210 212 210 protrusions Apex Sa (nm) 283 290 303 290 and recesses Rz (m) 34 34 35 34 on first Sm (m) 190 195 198 191 surface Radius of rotation R (m) 53 55 57 55 Pattern of Sa (nm) 220 231 225 215 protrusions Apex Sa (nm) 278 301 299 280 and recesses Rz (m) 33 35 32 35 on second Sm (m) 175 174 173 175 surface Radius of rotation R (m) 55 60 60 60 Intersection angle () between 90 90 90 90 engraved lines Evaluation Autohesion (N/15 cm) 7.8 7.9 7.8 7.7

(97) TABLE-US-00007 TABLE 7 Comparative Comparative Comparative Example 33 Example 7 Example 8 Example 9 First and Polyvinyl Average degree of 1700 1700 1700 1700 second butyral resin polymerization of PVA protective Butyralation degree 68.5 69 69 69 layers (mol %) Acetylation degree 0.5 1 1 1 (mol %) Hydroxy group content 31 30 30 30 (mol %) Amount (parts by mass) 100 100 100 100 Plasticizer Type 3GO 3GO 3GO 3GO Amount (parts by mass) 36 36 36 36 Structure Thickness (m) 350 350 350 350 Intermediate Polyvinyl Average degree of 1700 3000 3000 3000 layer butyral resin polymerization of PVA Butyralation degree 67 64.2 64.2 64.2 (mol %) Acetylation degree 8 12.5 12.5 12.5 (mol %) Hydroxy group content 25 23.3 23.3 23.3 (mol %) Amount (parts by mass) 100 100 100 100 Plasticizer Type 3GO 3GO 3GO 3GO Amount (parts by mass) 75 76.5 76.5 76.5 Structure Thickness (m) 100 100 100 100 Interlayer Structure Arrangement First protective First protective First protective First protective film as a layer/ layer/ layer/ layer/ whole Intermediate Intermediate Intermediate Intermediate layer/ layer/ layer/ layer/ Second Second Second Second protective layer protective layer protective layer protective layer Thickness (m) 800 800 800 800 First shape Formation Fine blast size (mesh) #320 #320 #800 #800 method (Production Example 1) Pattern of Sa (nm) 282 160 150 175 protrusions Rz (m) 16 9 22 23 and recesses on first surface Pattern of Sa (nm) 290 155 187 150 protrusions Rz (m) 16 10 19 16 and recesses on second surface Second Formation Embossing type (shape) Engraved lines Engraved lines shape method Pattern of Sa (nm) 205 130 protrusions Apex Sa (nm) 288 155 and recesses Rz (m) 35 31 on first Sm (m) 188 183 surface Radius of rotation R (m) 52 55 Pattern of Sa (nm) 208 134 protrusions Apex Sa (nm) 270 151 and recesses Rz (m) 36 32 on second Sm (m) 173 174 surface Radius of rotation R (m) 52 60 Intersection angle () between 90 20 engraved lines Evaluation Autohesion (N/15 cm) 7.5 53.1 29.0 25.0

Example 34

(98) A resin composition for an intermediate layer and a resin composition for a protective layer were obtained in the same manner as in Example 25, except that polyvinyl butyral having a composition as shown in Table 8 was used. The obtained resin composition for an intermediate layer and the obtained resin composition for a protective layer were co-extruded from a co-extruder into an interlayer film for a laminated glass including three layers, i.e., a first protective layer formed from the resin composition for a protective layer, an intermediate layer formed from the resin composition for an intermediate layer, and a second protective layer formed from the resin composition for a protective layer, which were stacked in the stated order. While the interlayer film for a laminated glass was formed, the first shape was also formed in conformity with Production Example 2.

(99) Specifically, while an interlayer film for a laminated glass was formed, the first shape was also formed in conformity with the embossing method in which melt fracture phenomena are controlled, under the following conditions: an extrusion amount per die width of 440 kg/hr.Math.m, a temperature of the film surface immediately after being extruded from the die of 200 C., a resin pressure at the die inlet of 80 kgf/cm.sup.2, and a water temperature in the water tank for cooling the film of 20 C. to 30 C. Here, the distance between the die and the surface of the cooling water tank was 100 mm.

(100) In the obtained interlayer film for a laminated glass, the first protective layer and the second protective layer both had a thickness of 350 m and the intermediate layer had a thickness of 100 m. The Sa value and the Rz value were measured by the same methods as in Example 1.

Examples 35 and 36 and Comparative Example 10

(101) An interlayer film for a laminated glass was produced in the same manner as in Example 34, except that the distance between the die and the surface of the cooling water tank for forming the first shape was changed as shown in Table 8, and the protrusions and recesses on both surfaces of the interlayer film were measured.

(102) (Evaluation)

(103) The interlayer films for a laminated glass obtained in Examples 34 to 36 and Comparative Example 10 were evaluated for autohesion by the same method as in Example 1. Table 8 shows the results.

(104) TABLE-US-00008 TABLE 8 Comparative Example 34 Example 35 Example 36 Example 10 First and Polyvinyl Average degree of 1700 1700 1700 1700 second butyral resin polymerization of PVA protective Butyralation degree 69.9 68.5 68.5 69.9 layers (mol %) Acetylation degree 1.1 0.5 0.5 1.1 (mol %) Hydroxy group content 29 31 31 29 (mol %) Amount (parts by mass) 100 100 100 100 Plasticizer Type 3GO 3GO 3GO 3GO Amount (parts by mass) 39 36 36 39 Structure Thickness (m) 350 350 350 350 Intermediate Polyvinyl Average degree of 2300 2300 3000 2300 layer butyral resin polymerization of PVA Butyralation degree 77.8 67 67 77.8 (mol %) Acetylation degree 1.5 8 8 1.5 (mol %) Hydroxy group content 20.7 25 25 20.7 (mol %) Amount (parts by mass) 100 100 100 100 Plasticizer Type 3GO 3GO 3GO 3GO Amount (parts by mass) 79 75 75 79 Structure Thickness (m) 100 100 100 100 Interlayer Structure Arrangement First protective First protective First protective First protective film as a layer/ layer/ layer/ layer/ whole Intermediate Intermediate Intermediate Intermediate layer/ layer/ layer/ layer/ Second Second Second Second protective layer protective layer protective layer protective layer Thickness (m) 800 800 800 800 First shape Formation Distance between die and 100 200 200 300 method water surface (mm) (Production Example 2) Pattern of Sa (nm) 388 278 295 140 protrusions Rz (m) 25 23 23 18 and recesses on first surface Pattern of Sa (nm) 374 290 278 137 protrusions Rz (m) 22 22 23 18 and recesses on second surface Second Formation Embossing type (shape) shape method Pattern of Sa (nm) protrusions Apex Sa (nm) and recesses Rz (m) on first Sm (m) surface Tip R (m) Pattern of Sa (nm) protrusions Apex Sa (nm) and recesses Rz (m) on second Sm (m) surface Tip R (m) Intersection angle () between engraved lines Evaluation Autohesion (N/15 cm) 10.2 16.0 15.8 39.0

Example 37

(105) (Production of an Interlayer Film for a Laminated Glass and Formation of First Shape)

(106) While an interlayer film for a laminated glass was formed, the first shape was also formed in the same manner as in Example 34.

(107) (Formation of Second Shape)

(108) Protrusions and recesses each having a groove shape with a continuous bottom were formed by the following procedure on the interlayer film for a laminated glass on which the first shape was formed. A pair of rolls including a metal roll having a surface milled with a triangular oblique line-type mill and a rubber roll having a JIS hardness of 45 to 75 was used as a device for transferring a pattern of protrusions and recesses. The interlayer film for a laminated glass having the first shape was passed through the device for transferring a pattern of protrusions and recesses, thereby forming protrusions and recesses on a first surface of the interlayer film for a laminated glass. The recesses each having a groove shape with a continuous bottom were parallel to each other at equal intervals. The transferring conditions employed here were a temperature of the interlayer film for a laminated glass of 70 C., a temperature of the rolls of 140 C., a linear velocity of 10 m/min, and a linear pressure of 1 to 100 kN/m. Then, the same operation was performed on a second surface of the interlayer film for a laminated glass to form recesses each having a groove shape with a continuous bottom. Here, the intersection angle between the recesses each having a groove shape with a continuous bottom (shape of an engraved line) formed on the first surface and the recesses each having a groove shape with a continuous bottom (shape of an engraved line) formed on the second surface was adjusted to 20. After the formation of the second shape, the protrusions and recesses on the first surface and the second surface were measured by the same method as in Example 4.

Example 38 and Comparative Example 11

(109) An interlayer film for a laminated glass was produced in the same manner as in Example 37 except the followings: polyvinyl butyral having a composition as shown in Table 9 was used; the distance between the die and the surface of the cooling water tank for forming the first shape was changed as shown in Table 9; the embossing shape and the pitch width for forming the second shape were changed as shown in Table 9; and the linear pressure for forming the second shape was adjusted to 1 to 100 kN/m to obtain desired roughness. Then, the protrusions and recesses on both surfaces of the interlayer film were measured.

(110) (Evaluation)

(111) The interlayer films for a laminated glass obtained in Examples 37 and 38 and Comparative Example 11 were evaluated for autohesion by the same method as in Example 1. Table 9 shows the results.

(112) TABLE-US-00009 TABLE 9 Comparative Example 37 Example 38 Example 11 First and Polyvinyl Average degree of 1700 1700 1700 second butyral resin polymerization of PVA protective Butyralation degree 69.9 68.5 68.5 layers (mol %) Acetylation degree 1.1 0.5 0.5 (mol %) Hydroxy group content 29 31 31 (mol %) Amount (parts by mass) 100 100 100 Plasticizer Type 3GO 3GO 3GO Amount (parts by mass) 39 36 36 Structure Thickness (m) 350 350 350 Intermediate Polyvinyl Average degree of 2300 2300 1700 layer butyral resin polymerization of PVA Butyralation degree 77.8 67 67 (mol %) Acetylation degree 1.5 8 8 (mol %) Hydroxy group content 20.7 25 25 (mol %) Amount (parts by mass) 100 100 100 Plasticizer Type 3GO 3GO 3GO Amount (parts by mass) 79 75 75 Structure Thickness (m) 100 100 100 Interlayer Structure Arrangement First protective First protective First protective film as a layer/ layer/ layer/ whole Intermediate Intermediate Intermediate layer/Second layer/Second layer/Second protective layer protective layer protective layer Thickness (m) 800 800 800 First shape Formation Distance between die and 100 200 300 method water surface (mm) (Production Example 2) Pattern of Sa (nm) 388 260 135 protrusions Rz (m) 26 17 19 and recesses on first surface Pattern of Sa (nm) 374 259 133 protrusions Rz (m) 22 18 18 and recesses on second surface Second Formation Embossing type (shape) Engraved lines Engraved lines Engraved lines shape method Pattern of Sa (nm) 320 209 98 protrusions Apex Sa (nm) 367 254 129 and recesses Rz (m) 44 43 37 on first Sm (m) 200 201 199 surface Tip R (m) 60 70 88 Pattern of Sa (nm) 33 209 105 protrusions Apex Sa (nm) 380 250 133 and recesses Rz (m) 44 43 41 on second Sm (m) 200 200 180 surface Tip R (m) 63 68 80 Intersection angle () between 20 90 90 engraved lines Evaluation Autohesion (N/15 cm) 8.8 6.5 28.0

INDUSTRIAL APPLICABILITY

(113) The present invention provides an interlayer film for a laminated glass which is easily peelable without autohesion even after storage in a stacked state, a laminated glass prepared using the interlayer film for a laminated glass, and a method for producing the interlayer film for a laminated glass.

REFERENCE SIGNS LIST

(114) 1 arbitrarily selected one recess 2 recess adjacent to the arbitrarily selected one recess 3 recess adjacent to the arbitrarily selected one recess A interval between the recess 1 and the recess 2 B interval between the recess 1 and the recess 3 10 interlayer film for a laminated glass 11 recess having a groove shape with a continuous bottom on a first surface 12 recess having a groove shape with a continuous bottom on a second surface 20 protrusions and recesses on a first surface or a second surface 21 recess having a groove shape with a continuous bottom 22 protrusion