Interlayer for laminated glass, and laminated glass

An interlayer film for laminated glass comprising:

• a first layer containing a polyvinyl acetal resin and a plasticizer;
• a second layer containing a polyvinyl acetal resin and a plasticizer;
• and
• a third layer containing a polyvinyl acetal resin and a plasticizer,
• wherein the second layer is laminated on a first surface of the first layer and the third layer is laminated on a second surface side of the first layer that is opposite to the first surface,
• wherein a degree of acetylation of the polyvinyl acetal resin in the first layer is greater than 10 mol % and less than 25 mol %,
• wherein a concentration of hydroxyl groups of the polyvinyl acetal resin in the first layer is different from a concentration of hydroxyl groups of the polyvinyl acetal resin in the second layer,
• wherein at least one of the first layer and the second layer contains a filler and a content of the filler is 5 parts by weight or greater with respect to 100 parts by weight of the polyvinyl acetal resin in a layer containing the polyvinyl acetal resin and the filler, and
• wherein, provided that a thickness of the interlayer film for laminated glass is T, a thickness of the first layer is 0.15 T or less, and
• wherein the filler is silica particles.