LIGHT CONTROL BODY AND LIGHT CONTROL WINDOWPANE

Abstract

The present invention provides a light control body and a light control windowpane which are capable of preventing reduction in light control performance even when used in an environment exposed to strong light for a long period of time. Provided is a light control body including: a light control layer; and a visible light absorbing layer having a visible light transmittance Tv at a wavelength of 380 to 780 nm of 50% or lower.

Claims

1. A light control body comprising: a light control layer; and a visible light absorbing layer having a visible light transmittance Tv at a wavelength of 380 to 780 nm of 50% or lower.

2. The light control body according to claim 1, wherein the light control layer contains a functional liquid crystal material.

3. The light control body according to claim 1, wherein the visible light absorbing layer has a visible light transmittance Tv at a wavelength of 380 to 780 nm of 30% or lower.

4. The light control body according to claim 1, wherein the visible light absorbing layer has a maximum value of a UV light transmittance at a wavelength of 370 to 400 nm of 30% or lower.

5. The light control body according to claim 1, wherein the visible light absorbing layer does not have a polarization property.

6. The light control body according to claim 1, wherein the visible light absorbing layer is a resin layer containing a thermoplastic resin and a colorant.

7. The light control body according to claim 6, wherein the thermoplastic resin is at least one selected from the group consisting of a polyvinyl acetal resin, an ethylene-vinyl acetate copolymer resin, an ethylene-(meth)acrylic acid copolymer resin, and an ionomer resin.

8. The light control body according to claim 6, wherein the visible light absorbing layer contains a UV absorber.

9. The light control body according to claim 8, wherein the UV absorber is a compound having a benzotriazole structure.

10. A light control windowpane comprising a laminated glass comprising: a pair of glass sheets; and the light control body according to claim 6 interposed between the pair of glass sheets.

11. The light control body according to claim 1, wherein the visible light absorbing layer is a colored glass.

12. A light control windowpane comprising the light control body according to claim 11.

Description

DESCRIPTION OF EMBODIMENTS

[0066] Embodiments of the present invention are more specifically described below with reference to, but not limited to, the following examples.

Example 1

(1) Preparation of Visible Light Absorbing Layer

[0067] To 40 parts by weight of triethylene glycol di-2-ethylhexanoate (3GO) were added 0.06 parts by weight of Tinuvin 970 (produced by BASF SE) and 0.2 parts by weight of Tinuvin 326 (produced by BASF SE) as UV absorbers. To the mixture were added 0.0005 parts by weight of copper phthalocyanine, 0.022 parts by weight of carbon black, and 0.0001 parts by weight of anthraquinone as colorants. To the mixture was further added magnesium acetate tetrahydrate as an adhesion modifier in such a manner that the concentration of the magnesium element in the visible light absorbing layer was set to 160 ppm, followed by mixing. Thus, a plasticizer solution was prepared. The entire amount of the obtained plasticizer solution and 100 parts by weight of a polyvinyl butyral resin (average degree of polymerization: 1,700, acetyl group content: 0.9 mol %, hydroxy group content: 30.6 mol %, degree of butyralization: 68.5 mol %) were sufficiently kneaded using a mixing roll to prepare a resin composition.

[0068] The obtained resin composition was extruded using an extruder to provide a visible light absorbing layer (PVB1) having a thickness of 380 m. The obtained PVB1 was colored gray.

[0069] The obtained PVB1 was analyzed using a spectrophotometer (U-4100 produced by Hitachi High-Technologies Corporation) in conformity with JIS R 3106. The visible light transmittance Tv at a wavelength of 380 to 780 nm was 16% and the maximum value of the UV light transmittance at a wavelength of 370 to 400 nm was 15%.

(2) Production of Light Control Body

[0070] A PDLC film 1 (LC MAGIC produced by Toppan Printing Co., Ltd., 30 cm in length30 cm in width, three-layer structure of ITO-sputtered PET/polymer dispersed liquid crystal/ITO-sputtered PET) having a thickness of 150 m was provided as a light control layer.

[0071] A laminate in which the PVB1 and the light control layer were stacked in the order of PVB1/light control layer/PVB1 was heat-bonded under the conditions of 80 C. for 10 minutes. Thus, a light control body having a thickness of 910 m was obtained.

(3) Production of Laminated Glass

[0072] The obtained light control body was interposed between a pair of clear glass sheets (visible light transmittance: 90.4%) having a size of 2.5 mm in thickness30 cm in length30 cm in width to prepare a laminate. The obtained laminate was pressed under vacuum at 90 C. for 30 minutes using a vacuum laminator to be press-bonded. The press-bonded laminate was subjected to 20-minute press-bonding under the conditions of 14 MPa at 140 C. using an autoclave, thereby obtaining a laminated glass.

Example 2

(1) Preparation of Visible Light Absorbing Layer

[0073] To 40 parts by weight of triethylene glycol di-2-ethylhexanoate (3GO) were added 0.01 parts by weight of Eusorb UV-1990 (produced by Eutech Chemical Co., Ltd.) and 0.2 parts by weight of Tinuvin 326 (produced by BASF SE) as UV absorbers. To the mixture were added 0.001 parts by weight of copper phthalocyanine and 0.022 parts by weight of carbon black as colorants. To the mixture were further added magnesium acetate tetrahydrate as an adhesion modifier in such a manner that the concentration of the magnesium element in the visible light absorbing layer was set to 160 ppm, followed by mixing. Thus, a plasticizer solution was prepared. The entire amount of the obtained plasticizer solution and 100 parts by weight of a polyvinyl butyral resin (average degree of polymerization: 1,700, acetyl group content: 0.9 mol %, hydroxy group content: 30.6 mol %, degree of butyralization: 68.5 mol %) were sufficiently kneaded using a mixing roll to prepare a resin composition.

[0074] The obtained resin composition was extruded using an extruder to provide a visible light absorbing layer (PVB2) having a thickness of 380 m. The obtained PVB2 was colored blue.

[0075] The obtained PVB2 was analyzed using a spectrophotometer (U-4100 produced by Hitachi High-Technologies Corporation) in conformity with JIS R 3106. The visible light transmittance Tv at a wavelength of 380 to 780 nm was 6% and the maximum value of the UV light transmittance at a wavelength of 370 to 400 nm was 15%.

(2) Production of Light Control Body and Laminated Glass

[0076] A PDLC film 1 having a thickness of 150 m was prepared as a light control layer.

[0077] A laminate in which the PVB2 and the light control layer were stacked in the order of PVB2/light control layer/PVB2 was heat-bonded under the conditions of 100 C. for 10 minutes. Thus, a light control body having a thickness of 910 m was obtained.

[0078] A laminated glass was obtained as in Example 1, except that the obtained light control body was used.

Example 3

(1) Preparation of Visible Light Non-Absorbing Layer

[0079] To 40 parts by weight of triethylene glycol di-2-ethylhexanoate (3GO) was added 0.2 parts by weight of Tinuvin 326 (produced by BASF SE) as a UV absorber. To the mixture was further added magnesium acetate tetrahydrate as an adhesion modifier in such a manner that the concentration of the magnesium element in the visible light absorbing layer was set to 160 ppm, followed by mixing. Thus, a plasticizer solution was prepared. The entire amount of the obtained plasticizer solution and 100 parts by weight of a polyvinyl butyral resin (average degree of polymerization: 1,700, acetyl group content: 0.9 mol %, hydroxy group content: 30.6 mol %, degree of butyralization: 68.5 mol %) were sufficiently kneaded using a mixing roll to prepare a resin composition.

[0080] The obtained resin composition was extruded using an extruder to provide a visible light non-absorbing layer (PVB0) having a thickness of 380 m. The obtained PVB0 was clear and transparent.

[0081] The obtained PVB0 was analyzed using a spectrophotometer (U-4100 produced by Hitachi High-Technologies Corporation) in conformity with JIS R 3106. The visible light transmittance Tv at a wavelength of 380 to 780 nm was 88.5% and the maximum value of the UV light transmittance at a wavelength of 370 to 400 nm was 40%.

(2) Production of Light Control Body and Laminated Glass

[0082] A PDLC film 1 having a thickness of 150 m was provided as a light control layer.

[0083] A laminate in which the PVB1, the light control layer, and the PVB0 were stacked in the order of PVB1/light control layer/PVB0 was heat-bonded under the conditions of 100 C. for 10 minutes. Thus, a light control body having a thickness of 910 m was obtained.

[0084] A laminated glass was obtained as in Example 1, except that the obtained light control body was used.

Example 4

[0085] A light control body and a laminated glass were obtained as in Example 1, except that the light control layer used was not the PDLC film 1 but a PDLC film 2 (LC MAGIC reverse mode produced by Toppan Printing Co., Ltd., 30 cm in length30 cm in width, three-layer structure of ITO-sputtered PET/polymer dispersed liquid crystal/ITO-sputtered PET).

Example 5

(1) Preparation of Visible Light Absorbing Layer

[0086] To 100 parts by weight of an ethylene-vinyl acetate copolymer resin (EVAFLEX EV170 produced by Du Pont-Mitsui Polychemicals, vinyl acetate content: 33% by mass) were added 0.06 parts by weight of Tinuvin 970 (produced by BASF SE) and 1.07 parts by weight of Tinuvin 326 (produced by BASF SE) as UV absorbers. To the mixture were further added 0.00065 parts by weight of copper phthalocyanine and 0.00013 parts by weight of anthraquinone as colorants. The mixture was sufficiently kneaded using a mixing roll to prepare a resin composition.

[0087] The obtained resin composition was extruded using an extruder to provide a visible light absorbing layer (EVA1) having a thickness of 380 m. The obtained EVA1 was colored green.

[0088] The obtained EVA1 was analyzed using a spectrophotometer (U-4100 produced by Hitachi High-Technologies Corporation) in conformity with JIS R 3106. The visible light transmittance Tv at a wavelength of 380 to 780 nm was 28% and the maximum value of the UV light transmittance at a wavelength of 370 to 400 nm was 15%.

(2) Production of Light Control Body and Laminated Glass

[0089] A sputtered electrochromic film (obtained by sputtering 10 nm of ITO/100 nm of NiO.sub.2/300 nm of Ta.sub.2O.sub.5/120 nm of WO.sub.3/10 nm of ITO on a polyethylene terephthalate (PET) substrate) having a thickness of 50 m was provided as a light control layer.

[0090] A laminate in which the EVA 1 and the light control layer were stacked in the order of EVA1/light control layer/EVA1 was heat-bonded under the conditions of 100 C. for 10 minutes. Thus, a light control body having a thickness of 810 m was obtained.

[0091] A laminated glass was obtained as in Example 1, except that the obtained light control body was used.

Example 6

(1) Preparation of Visible Light Absorbing Layer

[0092] To 100 parts by weight of an ethylene-vinyl acetate copolymer resin (EVAFLEX EV170 produced by Du Pont-Mitsui Polychemicals, vinyl acetate content: 33% by mass) were added 0.06 parts by weight of Tinuvin 970 (produced by BASF SE) and 1.07 parts by weight of Tinuvin 326 (produced by BASF SE) as UV absorbers. To the mixture were further added 0.0005 parts by weight of copper phthalocyanine and 0.0001 parts by weight of anthraquinone as colorants. The mixture was sufficiently kneaded using a mixing roll to prepare a resin composition.

[0093] The obtained resin composition was extruded using an extruder to provide a visible light absorbing layer (EVA2) having a thickness of 380 m. The obtained EVA2 was colored green.

[0094] The obtained EVA was analyzed using a spectrophotometer (U-4100 produced by Hitachi High-Technologies Corporation) in conformity with JIS R 3106.

[0095] The visible light transmittance Tv at a wavelength of 380 to 780 nm was 35% and the maximum value of the UV light transmittance at a wavelength of 370 to 400 nm was 15%.

(2) Production of Light Control Body and Laminated Glass

[0096] A sputtered electrochromic film (obtained by sputtering of 10 nm of ITO/100 nm of NiO.sub.2/300 nm of Ta.sub.2O.sub.5/120 nm of WO.sub.3/10 nm of ITO on a polyethylene terephthalate (PET) substrate) having a thickness of 50 m was provided as a light control layer.

[0097] A laminate in which the EVA2 and the light control layer were stacked in the order of EVA2/light control layer/EVA2 was heat-bonded under the conditions of 100 C. for 10 minutes. Thus, a light control body having a thickness of 810 m was obtained.

[0098] A laminated glass was obtained as in Example 1, except that the obtained light control body was used.

Example 7

(1) Preparation of Visible Light Absorbing Layer

[0099] To 100 parts by weight of an ionomer resin (Himilan 1707 produced by Du Pont-Mitsui Polychemicals) were added 0.06 parts by weight of Tinuvin 970 (produced by BASF SE) and 0.2 parts by weight of Tinuvin 326 (produced by BASF SE) as UV absorbers. To the mixture were further added 0.0005 parts by weight of copper phthalocyanine, 0.022 parts by weight of carbon black, and 0.0001 parts by weight of anthraquinone as colorants. The mixture was sufficiently kneaded using a mixing roll to prepare a resin composition.

[0100] The obtained resin composition was extruded using an extruder to provide a visible light absorbing layer (ionomer) having a thickness of 380 m. The obtained ionomer was colored gray.

[0101] The obtained ionomer was analyzed using a spectrophotometer (U-4100 produced by Hitachi High-Technologies Corporation) in conformity with JIS R 3106. The visible light transmittance Tv at a wavelength of 380 to 780 nm was 16% and the maximum value of the UV light transmittance at a wavelength of 370 to 400 nm was 15%.

(2) Production of Light Control Body and Laminated Glass

[0102] A PDLC film 1 having a thickness of 150 m was provided as a light control layer.

[0103] A laminate in which the ionomer and the light control layer were stacked in the order of ionomer/light control layer/ionomer was heat-bonded under the conditions of 100 C. for 10 minutes. Thus, a light control body having a thickness of 910 m was obtained.

[0104] A laminated glass was obtained as in Example 1, except that the obtained light control body was used.

Example 8

(1) Preparation of Visible Light Absorbing Layer

[0105] To 40 parts by weight of triethylene glycol di-2-ethylhexanoate (3GO) was added 0.2 parts by weight of Tinuvin 326 (produced by BASF SE) as a UV absorber. To the mixture were added 0.0005 parts by weight of copper phthalocyanine, 0.022 parts by weight of carbon black, and 0.0001 parts by weight of anthraquinone as colorants. To the mixture was further added magnesium acetate tetrahydrate as an adhesion modifier in such a manner that the concentration of the magnesium element in the visible light absorbing layer was set to 160 ppm, followed by mixing. Thus, a plasticizer solution was prepared. The entire amount of the obtained plasticizer solution and 100 parts by weight of a polyvinyl butyral resin (average degree of polymerization: 1,700, acetyl group content: 0.9 mol %, hydroxy group content: 30.6 mol %, degree of butyralization: 68.5 mol %) were sufficiently kneaded using a mixing roll to prepare a resin composition.

[0106] The obtained resin composition was extruded using an extruder to provide a visible light absorbing layer (PVB3) having a thickness of 360 m. The obtained PVB3 was colored gray.

[0107] The obtained PVB3 was analyzed using a spectrophotometer (U-4100 produced by Hitachi High-Technologies Corporation) in conformity with JIS R 3106.

[0108] The visible light transmittance Tv at a wavelength of 380 to 780 nm was 16% and the maximum value of the UV light transmittance at a wavelength of 370 to 400 nm was 15%.

(2) Production of Light Control Body and Laminated Glass

[0109] A PDLC film 1 (LCMSGIC produced by Toppan Printing Co., Ltd.) having a thickness of 150 m was provided as a light control layer.

[0110] A laminate in which the PVB3 and the light control layer were stacked in the order of PVB3/light control layer/PVB3 was heat-bonded under the conditions of 100 C. for 10 minutes. Thus, a light control body having a thickness of 910 m was obtained.

[0111] A laminated glass was obtained as in Example 1, except that the obtained light control body was used.

Example 9

(1) Preparation of Visible Light Absorbing Layer

[0112] To 40 parts by weight of triethylene glycol di-2-ethylhexanoate (3GO) were added 0.06 parts by weight of Tinuvin 970 (produced by BASF SE) and 0.2 parts by weight of Tinuvin 326 (produced by BASF SE) as UV absorbers. To the mixture were added 0.0002 parts by weight of copper phthalocyanine, 0.011 parts by weight of carbon black, and 0.0001 parts by weight of anthraquinone as colorants. To the mixture was further added magnesium acetate tetrahydrate as an adhesion modifier in such a manner that the concentration of the magnesium element in the visible light absorbing layer was set to 160 ppm, followed by mixing. Thus, a plasticizer solution was prepared. The entire amount of the obtained plasticizer solution and 100 parts by weight of a polyvinyl butyral resin (average degree of polymerization: 1,700, acetyl group content: 0.9 mol %, hydroxy group content: 30.6 mol %, degree of butyralization: 68.5 mol %) were sufficiently kneaded using a mixing roll to prepare a resin composition.

[0113] The obtained resin composition was extruded using an extruder to provide a visible light absorbing layer (PVB4) having a thickness of 380 m. The obtained PVB4 was colored light gray.

[0114] The obtained PVB4 was analyzed using a spectrophotometer (U-4100 produced by Hitachi High-Technologies Corporation) in conformity with JIS R 3106. The visible light transmittance Tv at a wavelength of 380 to 780 nm was 45% and the maximum value of the UV light transmittance at a wavelength of 370 to 400 nm was 15%.

(2) Production of Light Control Body and Laminated Glass

[0115] A PDLC film 1 having a thickness of 150 m was provided as a light control layer.

[0116] A laminate in which the PVB4 and the light control layer were stacked in the order of PVB4/light control layer/PVB4 was heat-bonded under the conditions of 100 C. for 10 minutes. Thus, a light control body having a thickness of 910 m was obtained.

[0117] A laminated glass was obtained as in Example 1, except that the obtained light control body was used.

Comparative Example 1

[0118] A visible light non-absorbing layer (PVB0) having a thickness of 380 m was obtained as in Example 3.

[0119] A PDLC film 1 having a thickness of 150 m was provided as a light control layer.

[0120] A laminate in which the PVB0 and the light control layer were stacked in the order of PVB0/light control layer/PVB0 was heat-bonded under the conditions of 100 C. for 10 minutes. Thus, a light control body having a thickness of 910 m was obtained.

[0121] A laminated glass was obtained as in Example 1, except that the obtained light control body was used.

Comparative Example 2

(1) Preparation of Visible Light Absorbing Layer

[0122] To 40 parts by weight of triethylene glycol di-2-ethylhexanoate (3GO) was added 0.2 parts by weight of Tinuvin 326 (produced by BASF SE) as a UV absorber. To the mixture were added 0.0002 parts by weight of copper phthalocyanine and 0.0001 parts by weight of anthraquinone as colorants. To the mixture was further added magnesium acetate tetrahydrate as an adhesion modifier in such a manner that the concentration of the magnesium element in the visible light absorbing layer was set to 160 ppm, followed by mixing. Thus, a plasticizer solution was prepared. The entire amount of the obtained plasticizer solution and 100 parts by weight of a polyvinyl butyral resin (average degree of polymerization: 1,700, acetyl group content: 0.9 mol %, hydroxy group content: 30.6 mol %, degree of butyralization: 68.5 mol %) were sufficiently kneaded using a mixing roll. Thus, a resin composition was obtained.

[0123] The obtained resin composition was extruded using an extruder to provide a visible light absorbing layer (PVB5) having a thickness of 380 m. The obtained PVB5 was colored yellow.

[0124] The obtained PVB5 was analyzed using a spectrophotometer (U-4100 produced by Hitachi High-Technologies Corporation) in conformity with JIS R 3106. The visible light transmittance Tv at a wavelength of 380 to 780 nm was 83% and the maximum value of the UV light transmittance at a wavelength of 370 to 400 nm was 15%.

(2) Production of Light Control Body and Laminated Glass

[0125] A PDLC film 1 having a thickness of 150 m was provided as a light control layer

[0126] A laminate in which the PVB 5 and the light control layer were stacked in the order of PVB5/light control layer/PVB5 was heat-bonded under the conditions of 100 C. for 10 minutes. Thus, a light control body having a thickness of 910 m was obtained.

[0127] A laminated glass was obtained as in Example 1, except that the obtained light control body was used.

Comparative Example 3

(1) Preparation of Visible Light Absorbing Layer

[0128] To 40 parts by weight of triethylene glycol di-2-ethylhexanoate (3GO) were added 0.06 parts by weight of Tinuvin 970 (produced by BASF SE) and 0.2 parts by weight of Tinuvin 326 (produced by BASF SE) as UV absorbers. To the mixture were added 0.00015 parts by weight of copper phthalocyanine, 0.0095 parts by weight of carbon black, and 0.0001 parts by weight of anthraquinone as colorants. To the mixture was further added magnesium acetate tetrahydrate as an adhesion modifier in such a manner that the concentration of the magnesium element in the visible light absorbing layer was set to 160 ppm, followed by mixing. Thus, a plasticizer solution was prepared. The entire amount of the obtained plasticizer solution and 100 parts by weight of a polyvinyl butyral resin (average degree of polymerization: 1,700, acetyl group content: 0.9 mol %, hydroxy group content: 30.6 mol %, degree of butyralization: 68.5 mol %) were sufficiently kneaded using a mixing roll to prepare a resin composition.

[0129] The obtained resin composition was extruded using an extruder to provide a visible light absorbing layer (PVB5) having a thickness of 380 m. The obtained PVB6 was colored light gray.

[0130] The obtained PVB6 was analyzed using a spectrophotometer (U-4100 produced by Hitachi High-Technologies Corporation) in conformity with JIS R 3106. The visible light transmittance Tv at a wavelength of 380 to 780 nm was 55% and the maximum value of the UV light transmittance at a wavelength of 370 to 400 nm was 15%.

(2) Production of Light Control Body and Laminated Glass

[0131] A PDLC film 1 having a thickness of 150 m was provided as a light control layer.

[0132] A laminate in which the PVB6 and the light control layer were stacked in the order of PVB6/light control layer/PVB6 was heat-bonded under the conditions of 100 C. for 10 minutes. Thus, a light control body having a thickness of 910 m was obtained.

[0133] A laminated glass was obtained as in Example 1, except that the obtained light control body was used.

Evaluation

[0134] The laminated glasses obtained in the examples and comparative examples were evaluated by the following methods.

[0135] Tables 1 to 3 show the results.

(1) Evaluation on Change in Appearance and Color Tone Before and after Light Resistance Test

[0136] The obtained laminated glass was irradiated with xenon light for 500 hours under the conditions of a black panel temperature of 83 C., an in-chamber temperature of 50 C., and a humidity of 50% RH. The irradiance of xenon light was set to be 180 W/m.sup.2 when measured at a wavelength of 300 to 400 nm. Quartz was used as an inner filter and quartz (#275) was used as an outer filter. The xenon tester used was SX-75 produced by Suga Test Instruments Co., Ltd. The laminated glass of Example 3 was irradiated from the PVB1 side.

[0137] The change in appearance before and after the light resistance test was visually evaluated. The change in color tone was evaluated in terms of the color difference E using a spectrophotometer (U-4100 produced by Hitachi High-Technologies Corporation).

(2) Evaluation 1 on Light Control Performance Before and after Light Resistance Test

[0138] A voltage (2 V) was applied to the light control body in the obtained laminated glass, and the appearance of the laminated glass with and without voltage application was visually observed.

[0139] Next, the obtained laminated glass was irradiated with xenon light under the same conditions as those for the evaluation on change in appearance and color tone.

[0140] To the light control body in the laminated glass after the light resistance test was applied a voltage (2 V), and whether the laminated glass can perform similar light control to that before the light resistance test was visually observed. The case where similar light control was performed was evaluated as 0 (Good) and the case where similar light control was not performed was evaluated as x (Poor).

TABLE-US-00001 TABLE 1 Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Structure Visible light absorbing Type PVB1 PVB2 PVB1 PVB1 EVA1 RVA2 of light layer/visible light Color Gray Blue Gray Gray Green Green control non-absorbing layer Visible light 16 6 16 16 28 35 body transmittance Tv (%) Maximum value of UV 15 15 15 15 15 15 light transmittance (%) Light control layer PDLC1 PDLC1 PDLC1 PDLC2 Sputtered Sputtered electro- electro- chromic film chromic film Visible light absorbing Type PVB1 PVB2 PVB0 PVB1 EVA1 EVA2 layer/visible light Color Gray Blue Clear & Gray Green Green non-absorbing layer colorless Visible light 16 6 88.5 16 28 35 transmittance Tv (%) Maximum value of UV 15 15 40 15 15 15 light transmittance (%) Evaluation Change in appearance Change in appearance None None None None None None and color tone Change in color 1.5 1.5 1.5 1.5 1.5 2.0 before/after light tone (E) resistance test Light control Not under application Gray & Blue & Gray & Gray & Green & Green & performance of voltage opaque vopaque opaque transparent opaque opaque Under application Gray & Blue & Gray & Gray & Green & Green & of voltage transparent transparent transparent opaque transparent transparent Light control performance after light resistance test

TABLE-US-00002 TABLE 2 Comparative Comparative Comparative Example 7 Example 8 Example 9 Example 1 Example 2 Example 3 Structure Visible light absorbing Type Ionomer PVB3 PVB4 PVB0 PVB5 PVB6 of light layer/visible light Color Gray Gray Light gray Clear & Yellow Light gray control non-absorbing layer colorless body Visible light 16 16 45 88.5 83 55 transmittance Tv (%) Maximum value of UV 15 15 15 40 15 15 light transmittance (%) Light control layer PDLC1 PDLC1 PDLC1 PDLC1 PDLC1 PDLC1 Visible light absorbing Type Ionomer PVB3 PVB4 PVB0 PVB5 PVB6 layer/visible light Color Gray Gray Light gray Clear & Yellow Light gray non-absorbing layer colorless Visible light 16 16 45 88.5 83 55 transmittance Tv (%) Maximum value of UV 15 15 15 40 15 15 light transmittance (%) Evaluation Change in appearance Change in appearance None None None Whitened Whitened None and color tone Change in color 1.5 2.0 1.5 6.3 1.5 1.5 before/after light tone (E) resistance test Light control Not under application Gray & Gray & Gray & Gray & Yellow & Gray & performance of voltage opaque opaque opaque opaque opaque opaque Under application Gray & Gray & Gray & Gray & Yellow & Gray & of voltage transparent transparent transparent transparent transparent transparent Light control performance X X X after light resistance test
(3) Evaluation 2 on Change in Appearance and Color Tone Before and after Light Resistance Test

[0141] The laminated glasses obtained in Example 1 and Comparative Example 1 were irradiated with xenon light under the conditions of a black panel temperature of 80 C., an in-chamber temperature of 45 C., and a humidity of 50% RH for 100 hours, 250 hours, and 1,000 hours. The irradiance of xenon light was set to be 120 W/m.sup.2 when measured at a wavelength of 300 to 400 nm. Quartz was used as an inner filter and quartz (#275) was used as an outer filter. The xenon tester used was SX-75 produced by Suga Test Instruments Co., Ltd.

[0142] For determining the change in appearance before and after the light resistance test, the yellow index (YI), and the values L*, a*, and b* in the CIE 1976 (L*a*b*) color space were measured using a spectrophotometer (U-4100 produced by Hitachi High-Technologies Corporation), and the change was determined in terms of L*, a*, b*, YI, and the color difference E. The measurement was performed at 0 C. in conformity with JIS R 3106 and JIS Z 8722.

[0143] The test was carried out with and without voltage application (2 V) to the light control body in the laminated glass.

TABLE-US-00003 TABLE 3 100 250 1000 hr hr hr Example 1 With voltage L* 0.16 0.18 0.20 application a* 0.13 0.15 0.17 b* 0.02 0.04 0.06 YI 0.04 0.06 0.08 E 0.21 0.24 0.27 Without voltage L* 0.16 0.14 0.12 application a* 0.01 0.08 0.10 b* 0.01 0.13 0.17 YI 0.13 0.33 0.53 E 0.16 0.21 0.23 Comparative With voltage L* 0.16 1.24 Unmeasurable Example 1 application a* 0.22 1.02 Unmeasurable b* 0.02 1.88 Unmeasurable YI 0.20 1.43 Unmeasurable E 0.27 2.47 Unmeasurable Without voltage L* 0.18 0.73 1.02 application a* 0.01 0.63 1.68 b* 0.02 2.28 5.28 YI 0.24 1.64 6.64 E 0.18 2.48 5.63

INDUSTRIAL APPLICABILITY

[0144] The present invention can provide a light control body and a light control windowpane which are capable of preventing reduction in light control performance even when used in an environment exposed to strong light for a long period of time.