Patent ID: 11945192
Assignee: SEKISUI CHEMICAL CO., LTD.
Field: Surface technology, coating (Chemistry)
Classification: CPC B  Y | IPC B

Claim 0:
1. An interlayer film for laminated glass having one end, and the other end being at an opposite side of the one end,
the other end having a thickness that is larger than a thickness of the one end,
the interlayer film as a whole having a wedge angle of 0.1 mrad or more,
an absolute value A in all sections A located every 150 mm in a measurement of partial wedge angles being 0.06 mrad or more and 0.4 mrad or less,
the measurement of partial wedge angles including measuring partial wedge angles of the interlayer film by steps 1 to 4 in this order,
the step 1 of selecting points A at 2-mm intervals starting at a position of 20 cm from the one end toward the other end of the interlayer film as a starting point and ending at a position of 20 cm from the other end toward the one end of the interlayer film as an ending point,
the step 2 of calculating a partial wedge angle A in each partial region A of 40 mm centered at each of the points A in a direction connecting the one end and the other end,
the step 3 of setting sections A every 150 mm from the starting point toward the ending point,
the step 4 of, in each section A, selecting a maximum value and a minimum value of all partial wedge angles A in partial regions A where the points A exist in the section A, and determining the absolute value A of difference between the maximum value and the minimum value,
the interlayer film containing a combination of (1) polyvinyl acetal resin consisting of polyvinyl acetal resin (X) that is obtained by acetalizing polyvinyl alcohol with an aldehyde, the aldehyde consisting of at least one of propionaldehyde, n-butyraldehyde, and isobutyraldehyde, and (2) plasticizer consisting of at least one of triethylene glycol di-2-ethylhexanoate and triethylene glycol di-2-ethylbutyrate,
the interlayer film having a region where the thickness increases from the one end side to the other end side,
the interlayer film having a portion where an increment of the thickness increases from the one end side to the other end side in the region where the thickness increases from the one end side to the other end side, or having a portion where an increment of the thickness decreases from the one end side to the other end side in the region. where the thickness increases from the one end side to the other end side.