Provided is an interlayer film for laminated glass which is excellent in sound insulation property and has improved sound insulation performance not only in a coincidence region but also in a mass-dominated region. The interlayer film for laminated glass includes a sound insulating layer which is formed from a composition (A) containing at least one resin (a1) selected from a thermoplastic resin and a thermosetting resin, wherein a tan δ obtained when a dynamic viscoelasticity of a sheet, which is obtained by molding the composition (A) to have a thickness of 0.8 mm, is measured at a frequency of 0.3 Hz in a tension mode has a maximal value at a temperature T.sub.A (° C.), T.sub.A (° C.) is in a range of −50 to 50° C., and the tan δ at T.sub.A (° C.) is 2.5 or more.

The present invention relates to resin particles including a residue unit represented by the following general formula (1) and having a volume average particle diameter equal to or more than 5 μm and equal to or less than 2000 μm, and a method for producing thereof. Furthermore the present invention relates to a fluororesin comprising a residue unit represented by a general formula (1) and having a weight average molecular weight Mw in a range of 5×10.sup.4 to 3×10.sup.5, and a yellow index of a heat-melted molded product (thickness 3 mm) after 24 h at 280° C. of equal to or less than 6, and a method for producing thereof. ##STR00001## In the formula (1), Rf.sub.1, Rf.sub.2, Rf.sub.3, and Rf.sub.4 are each independently one of the groups consisting of a fluorine atom, a linear perfluoroalkyl group having 1 to 7 carbon atoms, a branched perfluoroalkyl group having 3 to 7 carbon atoms, or a cyclic perfluoroalkyl group having 3 to 7 carbon atoms. The perfluoroalkyl group may have an ethereal oxygen atom. Further, Rf.sub.1, Rf.sub.2, Rf.sub.3, and Rf.sub.4 may be linked to one another to form a ring having 4 or more and 8 or less carbon atoms, and the ring may include an ethereal oxygen atom.

An object of the present disclosure is to provide an antenna cover base material that is coated with a fluoropolymer-containing film and that has excellent durability of water sliding. The present disclosure pertains to an antenna cover base material coated with a fluoropolymer-containing film, the film having the properties of a water sliding velocity of 150 mm/s or more at an inclination angle of 30°, and an average surface roughness (Ra) of 1 μm or less.

An object of the present disclosure is to provide a film that has high water slidability, and a substrate having a surface covered with the film. The present disclosure provides a film having the properties of a sliding velocity of 150 mm/s or more at an inclination angle of 30° and an average surface roughness (Ra) of 1 μm or less, and further provides a substrate having a surface covered with the film.

A polymer film comprising polyvinyl acetal and a laminated glass manufactured using the same are provided. At least one surface of the polymer film has a void volume (Vv) value at a material ratio of 10% ranging from 2 μm.sup.3/μm.sup.2 to 18 μm.sup.3/μm.sup.2, wherein the void volume (Vv) and material ratio are defined in accordance with ISO 25178-2:2012.

A polymer film comprising polyvinyl acetal and a laminated glass manufactured using the same are provided. At least one surface of the polymer film has a void volume (Vv) value at a material ratio of 10% ranging from 2 μm.sup.3/μm.sup.2 to 18 μm.sup.3/μm.sup.2, wherein the void volume (Vv) and material ratio are defined in accordance with ISO 25178-2:2012.

A method of producing a polyvinyl butyral resin composition including: preparing a reaction composition including i) a polyvinyl alcohol resin, ii) a butanal, and iii) a butanoic acid; and obtaining the polyvinyl butyral resin composition, wherein a conversion rate of butanal is 77% or more.

A method of producing a polyvinyl butyral resin composition including: preparing a reaction composition including i) a polyvinyl alcohol resin, ii) a butanal, and iii) a butanoic acid; and obtaining the polyvinyl butyral resin composition, wherein a conversion rate of butanal is 77% or more.

A polymer film comprising polyvinyl acetal and a laminated glass manufactured using the same are provided. At least one surface of the polymer film has a void volume (Vv) value at a material ratio of 10% ranging from 2 μm.sup.3/μm.sup.2 to 18 μm.sup.3/μm.sup.2, wherein the void volume (Vv) and material ratio are defined in accordance with ISO 25178-2:2012.

A polymer film comprising polyvinyl acetal and a laminated glass manufactured using the same are provided. At least one surface of the polymer film has a void volume (Vv) value at a material ratio of 10% ranging from 2 μm.sup.3/μm.sup.2 to 18 μm.sup.3/μm.sup.2, wherein the void volume (Vv) and material ratio are defined in accordance with ISO 25178-2:2012.