SURFACE TREATED FILLERS FOR POLYESTER FILMS Russian patent published in 2023 - IPC C08J5/18 B29C48/08 B32B27/20 B32B27/36 C08K3/26 C08K9/04 

FIELD: polyester films.

SUBSTANCE: polyester films, a method for their production and use. Proposed is a film for producing products containing at least one polyester in an amount ranging from 20.0 to <70 wt.%, selected from polyethylene terephthalate, polybutylene terephthalate, polytrimethylene terephthalate, polyethylene naphthalate, polyethylene furanoate; a thermoplastic polymer selected from a polyolefin comprising polypropylene, polyethylene, polybutylene, and a surface-treated filler material product in an amount ranging from >30 to 78.0 wt% in relation to the total weight of the layer, where the surface-treated filler material product contains A) at least one ground filler material containing calcium carbonate having a weighted median particle size d₅₀ ranging from 1.7 to 2.6 mcm, and B) a treatment layer on the surface of at least one pulverized filler material containing calcium carbonate that contains stearic acid, or at least one monosubstituted succinic anhydride, consisting of succinic anhydride, the monosubstituted group of which is selected from alkenyl, where the product material surface-treated filler contains a layer of processing in an amount of from 0.6 to 2.3 wt% in relation to the total dry weight of at least one crushed filler material containing calcium carbonate. Also proposed is a method for producing the said film, the use of a surface-treated filler material in the composition of the product film, an article containing the film, and the use of the film in packaging products.

EFFECT: proposed films have a reduced density, high opacity and good mechanical properties.

21 cl, 3 tbl, 3 ex