| 摘要 |
PROBLEM TO BE SOLVED: To obtain an interlayer for laminated sheet glass excellent in blocking resistance during the storage, handling operating efficiency when inserting the interlayer and deaerating properties in a preliminary press-bonding step by forming fine embossments having a specified surface roughness, recessed parts of a specified shape and protruding parts having a specified height and a specified base area on both surfaces of a thermoplastic resin sheet. SOLUTION: This interlayer for laminated sheet glass is obtained by forming embossments composed of fine unevennesses on both surfaces of a thermoplastic resin sheet such as a plasticized polyvinyl acetal. At this time, the surface roughness of the embossments on at least one surface is regulated to 0<Rvk / Rz <=0.25. The Rz (μm) is the average roughness of 10 points specified by DIN4768 and the Rvk is a converted valley depth determined from the Abbot's load curve specified by DIN4762 and 4776. The valley bottom of the recessed parts is a smooth plane and the sum total of the base area of the protruding parts having 20-100μm height is 25-55% based on the base area. The maximum diametral length of the base surface is preferably <=10 times based on the height and the diametral length intersecting the diametral length at right angles is preferably >=0.2 thereof.
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