A heat-shrinkable polyester film is provided, which has excellent high humidity storage stability, and effectively suppresses a breakage phenomenon of the film at the time of thermal shrinkage. A heat-shrinkable polyester film derived from a polyester resin composition including a crystalline polyester resin of 10% to 70% by weight satisfies the following configurations (a) and (b): (a) when upper yield point stresses in a stress-strain curve in an MD direction that orthogonally intersects a main shrinkage direction as measured before and after storage for 30 days under high humidity conditions of 23 C. and 50% RH are designated as E1 (MPa) and E2 (MPa), respectively, the E2 and E1 satisfy the following relational expression (1):

[00001]$\begin{array}{cc}0E2-E110& \left(1\right)\end{array}$ (b) a thermal shrinkage ratio A1 (main shrinkage direction at 98 C. for 10 seconds) has a value of 30 to 80%.

A method comprises providing a substrate, coating onto the substrate a composition comprising 3-30 weight percent based on total weight of the composition of a polyimide; a solvent comprising cyclopentanone in an amount of at least 70, preferably at least 80, more preferably at least 90 weight percent based on total weight of the solvent; and 0-15 weight % of one or more pigments, wherein the polyimide is soluble in the cyclopentanone at room temperature in the range of 5 to 30 weight percent, drying form a solid film on the substrate having a thickness of 1 to 5 micrometers. A composition useful in such method and an article made from such method are also disclosed.

Provided is a biaxially oriented polyester film in which poor flatness that may be caused during heat processing is suppressed. In the biaxially oriented polyester film, the content rate of an ester constituting unit derived from an isophthalic acid component is 0.5-5.0 mol % with respect to 100 mol % of all ester constituting units, the amount of change in haze of the film is 5.0% or less, the intrinsic viscosity of constitutional polyester resins is 0.59-0.65 dl/g, the average value of storage moduli is 5.0-7.610.sup.8 [Pa], the acid value of the film is 40-60 eq/ton, and the relational expression is satisfied: X(Ymax.sup.3Ymin.sup.3)0.0591(XYmin.sup.3)+0.005, where X is the storage modulus at 170 C., and Y is the film thickness per 1000 mm in the transverse direction with Ymax as the maximum value and Ymin as the minimum value.

A method of recovering a polymer material including: providing an extrudate formed from an article comprising the polymer material; contacting the extrudate with a solvent to form a mixture; separating the mixture from the contacted extrudate and recovering the polymer material from the mixture.

Provided in the present application is an identifiable substrate, including a base film and a marking layer, the base film including an identifying surface, the marking layer is an ink coating, in which the marking layer is laminated with the identifying surface of the base film; a surface tension of the identifying surface is D1; a surface tension of the marking layer is D2; and a thickness of the marking layer H satisfies 0.8 mH(D1/D2)5 m. In the present solution, the relative surface tension of the base film and the marking layer reflects the surface effect of the lamination between the base film and the marking layer. A thickness range of the marking layer is determined based thereon, so that the ink load on the surface of the base film is effectively controlled within the threshold value of the base film.

A method is provided of manufacturing a wind turbine blade shell member (36, 38), the method comprising the steps of providing a blade mould (96) for the blade shell member, arranging one or more layers of fibre material in the moulding cavity to provide a fibre layup (97), and providing a pre-manufactured spar cap member (62). The surface of the spar cap member is treated with a primer composition to provide a primer-treated surface. Heat is then applied to the primer-treated surface of the spar cap member to provide an activated surface, for improving the bonding in a subsequent resin co-infusion of the spar cap member and the fibre layup.

A thin plate molding material includes a resin composition containing a resin component and a filling material, and a reinforced fiber with a predetermined fiber length. The content ratio of the reinforced fiber is a predetermined ratio. The mixing ratio of the resin component is a predetermined ratio.

There is provided a method of coating a substrate comprising applying a first mixture where the first mixture reacts to form covalent bonds to the substrate surface and where the unreacted parts of the first mixture undergo diffusive mixing with a second layer, which is applied on top of the first mixture. This avoids creation of a weak layer, which may otherwise give lower adhesion. The adhesion as well as mechanical properties including the scratch resistance are improved.

Provided is a ternary biodegradable polymer composition including biodegradable PLA, amorphous PHA, and PBAT, and a method of preparing the same, and more specifically a composition in which amorphous PHA acts as a compatibilizer for PLA and PBAT, thereby improving the tensile strength, impact strength, and transparency of the ternary biodegradable polymer composition. The ternary biodegradable polymer composition uses a biomass-based biodegradable polymer such as PLA or aPHA and a petroleum-based biodegradable resin such as PBAT to increase the content of the biomass-based biodegradable polymer while minimizing the content of the petroleum-based biodegradable resin, thereby providing a more environmentally friendly biodegradable plastic composition.

A heat-shrinkable polyester film is provided, in which the loss coefficient and the like are controlled in a plurality of temperature regions, and which has excellent wrinkle resistance characteristics. The heat-shrinkable polyester film is a heat-shrinkable polyester film derived from a polyester resin composition containing 30% to 90% by weight of an amorphous polyester resin and 10% to 70% by weight of a crystalline polyester resin with respect to the total amount, in which (a) a loss coefficient obtained using a dynamic viscoelasticity measuring apparatus has a first loss coefficient peak in a temperature region of below 100 C.; (b) a loss coefficient obtained in the same manner has a second loss coefficient peak in a temperature region of 100 C. or higher; and (c) a heat shrinkage ratio obtained when the film is immersed in hot water at 80 C. for 10 seconds is 30% or more.