This invention relates to a a one-step process for making a polymer composite suspension for coating plastic films characterized in that a first polymer is synthesized in-situ optionally in the presence of other polymers and in the presence of clay. Preferably the polymer composite suspension comprises a) 1.0 to 11.0 wt % of clay or silane modified clay, b) 0.1 to 10.0 wt % of poly (acrylic acid), which is a copolymer of acrylic acid (AA) with at least one other monomer selected from 2-ethylhexyl acrylate (ERA), β-carboxyethyl acrylate (β-CEA), methacrylamidoethyl ethylene urea (WAM II) and ethoxylated behenyl methacrylate (β-EHA), c) 1.0 to 15.0 wt % of other polymers, preferably poly (vinyl alcohol) and d) 70 to 97 wt % of water or mixture of water with 2-propanol. The coating films made from the suspensions show good barrier capabilities against water vapor and oxygen can be used to make barrier layers on or within plastic films for packaging applications. The invention also relates to methods for making silane modified clay usable in the process for making the suspensions.

This invention relates to a a one-step process for making a polymer composite suspension for coating plastic films characterized in that a first polymer is synthesized in-situ optionally in the presence of other polymers and in the presence of clay. Preferably the polymer composite suspension comprises a) 1.0 to 11.0 wt % of clay or silane modified clay, b) 0.1 to 10.0 wt % of poly (acrylic acid), which is a copolymer of acrylic acid (AA) with at least one other monomer selected from 2-ethylhexyl acrylate (ERA), β-carboxyethyl acrylate (β-CEA), methacrylamidoethyl ethylene urea (WAM II) and ethoxylated behenyl methacrylate (β-EHA), c) 1.0 to 15.0 wt % of other polymers, preferably poly (vinyl alcohol) and d) 70 to 97 wt % of water or mixture of water with 2-propanol. The coating films made from the suspensions show good barrier capabilities against water vapor and oxygen can be used to make barrier layers on or within plastic films for packaging applications. The invention also relates to methods for making silane modified clay usable in the process for making the suspensions.

A gas barrier film formed of a cured product of a mixture including a polycarboxylic acid, a polyamine compound, and a polyvalent metal compound, in which in an infrared absorption spectrum of the gas barrier film, an area ratio of an amide bond represented by B/A is equal to or less than 0.380, an area ratio of a carboxylic acid represented by C/A is equal to or less than 0.150, and an area ratio of carboxylate represented by D/A is equal to or more than 0.520.

A gas barrier film formed of a cured product of a mixture including a polycarboxylic acid, a polyamine compound, and a polyvalent metal compound, in which in an infrared absorption spectrum of the gas barrier film, an area ratio of an amide bond represented by B/A is equal to or less than 0.380, an area ratio of a carboxylic acid represented by C/A is equal to or less than 0.150, and an area ratio of carboxylate represented by D/A is equal to or more than 0.520.

The invention provides a multilayer film comprising a substrate film and a coating layer arranged on at least one surface of the substrate film, wherein the coating layer contains an oxazoline group and comprises an acrylic resin, the coating layer has a thickness (D) of 5-150 nm, and the ratio (Pl/P2) of the peak intensity (P1) of a peak that has an absorption maximum in a region of 1655±10 cm.sup.−1 to the peak intensity (P2) of a peak that has an absorption maximum in a range of 1580±10 cm.sup.−1 in the total reflection infrared absorption spectrum of the coating layer and the thickness (D) of the coating layer fulfill the relationship represented by the formula: 0.03≤(Pl/P2)/D≤0.15.

The invention provides a multilayer film comprising a substrate film and a coating layer arranged on at least one surface of the substrate film, wherein the coating layer contains an oxazoline group and comprises an acrylic resin, the coating layer has a thickness (D) of 5-150 nm, and the ratio (Pl/P2) of the peak intensity (P1) of a peak that has an absorption maximum in a region of 1655±10 cm.sup.−1 to the peak intensity (P2) of a peak that has an absorption maximum in a range of 1580±10 cm.sup.−1 in the total reflection infrared absorption spectrum of the coating layer and the thickness (D) of the coating layer fulfill the relationship represented by the formula: 0.03≤(Pl/P2)/D≤0.15.

In a gas-barrier aluminum deposition film according to one embodiment of the present invention, a seed coating layer containing functional groups of at least one type selected from among a hydroxyl group (—OH), an amine group (—NH), and a carboxylic acid group (—COOH) is formed on a thermoplastic plastic base film to form a seed molecular layer that enables uniform deposition of aluminum, such as AlOx or AlNx, through chemical reaction, on a surface of the coating layer, with aluminum atoms vaporized at the initial stage of aluminum deposition, thereby inducing uniform deposition of an aluminum layer to be subsequently deposited. Therefore, it is possible to provide a deposited film having superior oxygen and water vapor barrier properties compared to existing aluminum deposition films.

Methods for making films including a water-soluble polymeric material and a vapor-deposited inorganic coating are disclosed. The method comprises providing a layer of water-soluble polymeric material and vapor depositing an inorganic coating to at least one surface of the layer of water-soluble polymeric material, wherein the inorganic coating comprises a metal oxide. The method further comprises forming a plurality of microfractures extending along the surface of the inorganic coating.

Methods for making films including a water-soluble polymeric material and a vapor-deposited inorganic coating are disclosed. The method comprises providing a layer of water-soluble polymeric material and vapor depositing an inorganic coating to at least one surface of the layer of water-soluble polymeric material, wherein the inorganic coating comprises a metal oxide. The method further comprises forming a plurality of microfractures extending along the surface of the inorganic coating.

A method of applying a gas-impermeable coating includes forming a polyelectrolyte complex suspension. The polyelectrolyte complex suspension is applied to a substrate. The substrate having the polyelectrolyte complex applied thereon is treated. The treating reduces salt content of the polyelectrolyte complex. The treating results in a gas-impermeable coating being formed on the substrate