Interlayer film for colored laminated glass, and colored laminated glass

Abstract

The present invention aims to provide an interlayer film for a colored laminated glass which exhibits a visible light transmittance Tv of 5% or lower, small variation in visible light transmittance and an excellent appearance when incorporated in a laminated glass together with two clear glass plates in conformity with JIS R3202 (1996), and a colored laminated glass produced using the interlayer film for a colored laminated glass. Provided is an interlayer film for a colored laminated glass having, recesses on at least one surface, and exhibiting a visible light transmittance Tv of 5% or lower when incorporated in a laminated glass together with two clear glass plates in conformity with JIS R3202 (1996), the interlayer film for a colored laminated glass including a laminate of at least two layers including a first resin layer containing a thermoplastic resin and a colorant and a second resin layer containing a thermoplastic resin and no colorant, the elastic modulus E.sub.1 of the first resin layer and the elastic modulus B.sub.2 of the second resin layer having a ratio E.sub.1/E.sub.2 of 1.25 or more, the thickness t.sub.1 of the first resin layer and the thickness t.sub.2 of the second resin layer having a ratio t.sub.1/t.sub.2 of 2.0 or less.

Claims

1. An interlayer film for a colored laminated glass, the interlayer film having recesses on at least one surface thereof and exhibiting visible light transmittance Tv of 5% or lower when incorporated in a laminated glass together with two clear glass plates in conformity with JIS R3202 (1996), the interlayer film for a colored laminated glass comprising a laminate of at least two layers including a first resin layer containing a thermoplastic resin and a colorant and a second resin layer containing a thermoplastic resin and no colorant, wherein a tensile elastic modulus E.sub.1 of the first resin layer and a tensile elastic modulus E.sub.2 of the second resin layer have a ratio E.sub.1/E.sub.2 of 1.25 or more, the thickness t.sub.1 of the first resin layer and the thickness t.sub.2 of the second resin layer have a ratio t.sub.1/t.sub.2 of 2.0 or less, and a CV value of visible light transmittance (%) obtained by a following equation is 23.7% or less: CV value=standard deviation/average of visible light transmittance100.

2. The interlayer film for a colored laminated glass according to claim 1, comprising a laminate of at least three layers including a first resin layer interposed between two second resin layers.

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

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

Description

BRIEF DESCRIPTION OF DRAWINGS

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

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

(3) FIG. 3 is a 3D roughness image data obtained by the measurement using a 3D profilometer performed on a surface of an interlayer film for a laminated glass having recesses each having a groove shape with a continuous bottom on the surface.

DESCRIPTION OF EMBODIMENTS

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

Example 1

(5) (1) Preparation of a Resin Composition for First Resin Layers

(6) Polyvinyl alcohol having an average degree of polymerization of 1,700 was acetalized using n-butyraldehyde to provide polyvinyl butyral having an acetyl group content of 1 mol %, a butyral group content of 69 mol %, and a hydroxy group content of 30 mol % (hereafter, also referred to as PVB). To 100 parts by mass of the obtained PVB were added 40 parts by mass of triethylene glycol-di-2-ethylhexanoate (3GO) as a plasticizer and carbon black as a colorant, and they were sufficiently kneaded using a mixing roll to prepare a resin composition for first resin layers. The amount of the added colorant was set to 0.095% by mass in 100% by mass of the first resin layer and 0.038% by mass in 100% by mass of the entire interlayer film for a colored laminated glass to be obtained.

(7) (2) Preparation of a Resin Composition for Second Resin Layers

(8) To 100 parts by mass of the PVB was added 40 parts by mass of triethylene glycol-di-2-ethylhexanoate (3GO) as a plasticizer, and they were sufficiently kneaded using a mixing roll to prepare a resin composition for second resin layers.

(9) (3) Production of an Interlayer Film for a Colored Laminated Glass

(10) The obtained resin composition for first resin layers and resin composition for second resin layers were extruded from a co-extruder under the condition of an extrusion temperature of 200 C., thereby preparing a laminate having a two-layer structure (first resin layer/second resin layer).

(11) (4) Formation of Recesses

(12) A pair of embossing rolls having a large number of fine recesses and a large number of fine protrusions formed thereon was used as a device for transferring fine protrusions and recesses. The obtained laminate was passed through the embossing rolls. Thus, a laminate having a large number of fine recesses and a large number of fine protrusions formed thereon was prepared.

(13) Another pair of embossing rolls was further used as a device for transferring protrusions and recesses. The obtained laminate having a large number of fine recesses and a large number of fine protrusions formed thereon was passed through the embossing rolls, and to the both surfaces of the laminate were formed recesses having a surface roughness (Rz) of 31 m in which recesses each having a groove shape with a continuous bottom (shape of an engraved line) were formed in parallel to each other at equal intervals. Thus, an interlayer film for a colored laminated glass was obtained. The pairs of embossing rolls each include 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.

(14) The surface roughness Rz was measured by a method in conformity with JIS B-0601 (1994). The transferring conditions for formation of the recesses each having a groove shape (shape of an engraved line) were a temperature of a laminate of 95 C., a roll temperature of 130 C., and a press pressure of 500 kPa.

(15) The elastic modulus and thickness of each resin layer in the obtained interlayer film for a colored laminated glass were measured by the methods described above.

(16) The first resin layer had an elastic modulus E.sub.1 of 9.6 N/mm.sup.2 and a thickness t.sub.1 of 305 m. The second resin layer had an elastic modulus E.sub.2 of 7.0 N/mm.sup.2 and a thickness t.sub.2 of 455 m.

(17) (5) Production of a Colored Laminated Glass

(18) The obtained interlayer film for a colored laminated glass was sandwiched between a pair of clear glass plates (5 cm in length5 cm in width, 1.0 mm in thickness) to prepare a laminate. The obtained laminate was press-bonded under vacuum at 90 C. for 30 minutes using a vacuum laminator. The press-bonded laminate was further press-bonded for 20 minutes under 14 MPa at 140 C. using an autoclave. Thus, a colored laminated glass was obtained.

Examples 2 and 3

(19) An interlayer film for a colored laminated glass having a three-layer structure (second resin layer/first resin layer/second resin layer) was produced in which the amount of the colorant and the thickness of each resin layer were adjusted to the values as shown in Table 1, and a colored laminated glass was obtained. The interlayer film for a colored laminated glass and laminated glass were produced as in Example 1.

Comparative Example 1

(20) In the preparation of a resin composition for first resin layers, the amount of the added colorant was changed to 0.052% by mass in 100% by mass of the resulting first resin layer and 0.037% by mass in 100% by mass of the entire interlayer film for a colored laminated glass to be obtained. Using this resin composition for first resin layers, an interlayer film for a colored laminated glass having a three-layer structure in which the thickness of each resin layer was adjusted to the value as shown in Table 1 was produced and then a colored laminated glass was obtained as in Example 2.

Comparative Example 2

(21) In the preparation of a resin composition for first resin layers, the amount of the added colorant was changed to 0.043% by mass in 100% by mass of the resulting first resin layer and 0.037% by mass in 100% by mass of the entire interlayer film for a colored laminated glass to be obtained. Using this resin composition for first resin layers, an interlayer film for a colored laminated glass having a three-layer structure in which the thickness of each resin layer was adjusted to the value as shown in Table 1 was produced as in Example 2.

Examples 4 to 8, Comparative Examples 3 to 6

(22) An interlayer film for a colored laminated glass and a colored laminated glass were obtained as in Example 1, except that the amount of the plasticizer, the concentration of the colorant, and the thickness of each resin layer were changed as shown in Table 2.

(23) (Evaluation)

(24) The interlayer films for a laminated glass obtained in the examples and comparative examples were evaluated by the following method. Tables 1 and 2 show the results.

(25) (Measurement of Visible Light Transmittance)

(26) The visible light transmittance within a wavelength range of 380 to 780 nm was measured at an arbitrarily selected 20 sites on the obtained laminated glass using a spectrophotometer (U-4100 available from Hitachi High-Technologies Corporation) in conformity with JIS R 3106 (1998).

(27) The average and the standard deviation of the visible light transmittances measured at 20 sites were obtained. The obtained standard deviation was divided by the average of the visible light transmittances, and the quotient was centupled. The obtained value (standard deviation/average of visible light transmittance100) was defined as a CV value.

(28) The visible light transmittance of the clear glass plates used in the examples and comparative examples was 90.5%.

(29) TABLE-US-00001 TABLE 1 Example Example Example Comparative Comparative 1 2 3 Example 1 Example 2 Resin First resin layer Resin Kind PVB PVB PVB PVB PVB composition Parts by mass 100 100 100 100 100 Plasticizer Kind 3GO 3GO 3GO 3GO 3GO Parts by mass 40 40 40 40 40 Colorant Kind Carbon Carbon Carbon Carbon Carbon black black black black black % by mass 0.095 0.095 0.072 0.052 0.043 Second resin layer Resin Kind PVB PVB PVB PVB PVB Parts by mass 100 100 100 100 100 Plasticizer Kind 3GO 3GO 3GO 3GO 3GO Parts by mass 40 40 40 40 40 Interlayer Second resin layer Young's modulus E.sub.2 N/mm.sup.2 7.0 7.0 7.0 7.0 7.0 film for Thickness t.sub.2 m 455 235 180 110 55 laminated First resin layer Young's modulus E.sub.1 N/mm.sup.2 9.6 9.6 9.0 8.5 8.2 glass Thickness t.sub.1 m 305 300 400 540 650 Second resin layer Young's modulus E.sub.2 N/mm.sup.2 7.0 7.0 7.0 7.0 Thickness t.sub.2 m 225 180 110 55 Entire interlayer film Colorant % by mass 0.038 0.038 0.038 0.037 0.037 E.sub.1/E.sub.2 1.37 1.37 1.29 1.21 1.17 t.sub.1/t.sub.2 0.67 1.28 2.22 4.91 11.82 Evaluation Average of visible light transmittance Tv (%) 1.52 1.49 1.60 2.26 2.44 CV value of visible light transmittance (%) 25.8 24.6 24.4 31.2 38.5

(30) TABLE-US-00002 TABLE 2 Example 4 Example 5 Example 6 Example 7 Example 8 Resin First resin layer Resin Kind PVB PVB PVB PVB PVB composition Parts by mass 100 100 100 100 100 Plasticizer Kind 3GO 3GO 3GO 3GO 3GO Parts by mass 40 40 41 42 40 Colorant Kind Carbon black Carbon black Carbon black Carbon black Carbon black % by mass 0.171 0.183 0.176 0.289 0.123 Second resin layer Resin Kind PVB PVB PVB PVB PVB Parts by mass 100 100 100 100 100 Plasticizer Kind 3GO 3GO 3GO 3GO 3GO Parts by mass 40 40 39 38 40 Interlayer Second resin layer Young's modulus E.sub.2 N/mm.sup.2 7.0 7.0 8.1 9.3 7.0 film for Thickness t.sub.2 m 170 170 170 320 270 laminated First resin layer Young's modulus E.sub.1 N/mm.sup.2 11.0 11.2 10.1 12.0 9.8 glass Thickness t.sub.1 m 170 150 170 100 210 Second resin layer Young's modulus E.sub.2 N/mm.sup.2 7 7.0 8.1 9.3 7.0 Thickness t.sub.2 m 160 180 160 340 280 Entire interlayer film Colorant % by mass 0.058 0.055 0.060 0.038 0.034 E.sub.1/E.sub.2 1.57 1.60 1.25 1.29 1.40 t.sub.1/t.sub.2 1.06 0.83 1.06 0.29 0.75 Evaluation Average of visible light transmittance Tv (%) 1.93 3.96 2.06 1.52 4.80 CV value of visible light transmittance (%) 20.5 10.0 19.3 23.7 8.2 Comparative Comparative Comparative Comparative Example 3 Example 4 Example 5 Example 6 Resin First resin layer Resin Kind PVB PVB PVB PVB composition Parts by mass 100 100 100 100 Plasticizer Kind 3GO 3GO 3GO 3GO Parts by mass 41 40 41 39 Colorant Kind Carbon black Carbon black Carbon black carbon black % by mass 0.121 0.097 0.096 0.053 Second resin layer Resin Kind PVB PVB PVB PVB Parts by mass 100 100 100 100 Plasticizer Kind 3GO 3GO 3GO 3GO Parts by mass 39 40 40 41 Interlayer Second resin layer Young's modulus E.sub.2 N/mm.sup.2 8.1 7.0 7.0 6.1 film for Thickness t.sub.2 m 130 98 235 110 laminated First resin layer Young's modulus E.sub.1 N/mm.sup.2 8.9 9.2 8.3 9.3 glass Thickness t.sub.1 m 240 300 300 540 Second resin layer Young's modulus E.sub.2 N/mm.sup.2 8.1 7.0 7.0 6.1 Thickness t.sub.2 m 130 102 225 110 Entire interlayer film Colorant % by mass 0.058 0.058 0.038 0.038 E.sub.1/E.sub.2 1.09 1.32 1.18 1.52 t.sub.1/t.sub.2 1.85 2.94 1.00 4.91 Evaluation Average of visible light transmittance Tv (%) 1.95 2.02 1.58 1.62 CV value of visible light transmittance (%) 30.2 36.3 27.9 29.8

INDUSTRIAL APPLICABILITY

(31) The present invention can provide an interlayer film for a colored laminated glass which exhibits, when incorporated in a laminated glass together with two clear glass plates in conformity with JIS R3202 (1996), a visible light transmittance Tv of 5% or lower, small variation in visible light transmittance from portion to portion and an excellent appearance, and a colored laminated glass produced using the interlayer film for a colored laminated glass.