Ultrafine particle dispersion composition, composition for interlayer for laminated glass, interlayer and laminated glass

The present invention relates to an ultrafine particle dispersion composition containing infrared ray shielding ultrafine particles (hereinafter referred to as "ultrafine particles"), a composition for an interlayer for a laminated glass, an interlayer employing it, and a laminated glass. Particularly, it relates to a fine particle dispersion composition wherein ultrafine particles are uniformly dispersed and whereby it is possible to obtain shaped resin products excellent in transparency and having the ultrafine particles uniformly dispersed, by incorporating it to various shaped resin products. Further, it relates to a composition for an interlayer capable of forming an interlayer which is transparent and excellent in the infrared ray shielding performance and which has a small haze value, when used as an interlayer for a laminated glass, an interlayer employing it, and a laminated glass. By incorporating and dispersing infrared ray shielding ultrafine particles having an average particle size of from 10 to 60 nm and a volume ratio of ultrafine particles having particle sizes of at least 60 nm being at most 15% of all particles, in a plasticizer, it is possible to obtain an ultrafine particle dispersion composition having the ultrafine particles uniformly dispersed. By using this composition, it is possible to obtain a laminated glass or an interlayer of a laminated glass, which has a small haze value and which is excellent in the infrared ray shielding performance.