Kuraray Co., Ltd.

Sayaka Shimizu

Minoru Okamoto

Osamu Kazeto

Mitsunori Asada

Provided are a water-soluble film that causes less deformation of the package during storage, while maintaining excellent solubility in water, and is capable of suppressing the occurrence of tears and the like, a production method thereof, and a package using the water-soluble film. A water-soluble film of the present invention includes a polyvinyl alcohol resin. The water-soluble film has an amount (A1) of crystalline component of 60% or less and an amount (A2) of constrained amorphous component from 10% to 50%, the amounts being obtained from a spin-spin relaxation curve byH pulse NMR measurement of the water-soluble film in deuterated methanol. A ratio (A1/A2) of the amount (A1) of crystalline component to the amount (A2) of constrained amorphous component is preferably from 0.1 to 5.

Water-soluble film, method of manufacturing same, and package

Provided are a water-soluble film capable of maintaining good mechanical strength even when packaging a liquid detergent and the like while maintaining excellent water solubility of the water-soluble film and a package using the same. A water-soluble film of the present invention includes a polyvinyl alcohol resin. When a crystallinity index calculated for a first surface is Fd1 and a crystallinity index calculated for a second surface opposed to the first surface is Fd2 for FT-IR measurement of respective two surfaces of the water-soluble film by ATR technique using a diamond prism, the Fd1 and the Fd2 are 0.22≤Fd1≤0.72, 0.2≤Fd2≤0.65 and Fd1/Fd2≥1.1.

Water-soluble film and package

Provided are a water-soluble film having excellent solubility in water and capable of reducing the stickiness of the contact surfaces to each other at the edges during storage in rolls, a production method thereof, and a package using the water-soluble film. A water-soluble film of the present invention includes a polyvinyl alcohol resin. The water-soluble film satisfies a formula (1) below when amounts of crystalline component are respectively (A1), (A1), and (A1), the amounts being obtained from a spin-spin relaxation curve byH pulse NMR measurement of the water-soluble film immediately after, 60 seconds after, and 180 seconds after the water-soluble film is immersed in a mixed solution of deuterated water and deuterated methanol mixed at a volume ratio of 1:1 at 5° C.

There is provided a water-soluble film containing polyvinyl alcohol resin, wherein a ratio RSm (LD/TD) is 1.2 or greater and 2.5 or less, where the RSm (LD/TD) is the ratio of an average length RSm (LD) of roughness curve elements on at least one film surface in the longitudinal direction to an average length RSm (TD) of roughness curve elements on the same film surface in the transverse direction. This allows provision of a water-soluble film that can be suitably used for manufacturing a package with excellent uniformity of seal strength, even for manufacturing a package with excellent uniformity of seal strength during high-speed sealing; and a package using the film.

A water-soluble film is provided that is excellent in film transparency and water solubility and inhibits sticking between the films. A water-soluble film includes a polyvinyl alcohol resin, wherein a crystallite size obtained from an X-ray profile obtained by wide-angle X-ray measurement is from 4.0 to 5.5 nm and a degree of crystallization obtained from the X-ray profile is from 10.0% to 25.0%, and an external haze is from 7.0% to 30.0%.

Provided are a water-soluble PVA film having good water sealing properties in addition to excellent water solubility while maintaining mechanical strength of the water-soluble PVA film and a package using the same. A water-soluble film of the present invention includes a polyvinyl alcohol resin. When a crystallinity index calculated using a diamond prism is Fd1 and a crystallinity index calculated using a germanium prism is Fg1 for FT-IR measurement of a first surface of the water-soluble film by ATR technique, Fd1 and Fg1 are 0.25≤Fd1≤0.65 and Fd1/Fg1>1. Fd1 and Fg1 are preferably Fd1/Fg1≤1.5.

Provided are a water-soluble film capable of inhibiting sticking between the films while maintaining excellent water solubility and a package using the same. A water-soluble film of the present invention includes a polyvinyl alcohol resin. When a crystallinity index calculated using a diamond prism is Fd1 and a crystallinity index calculated using a germanium prism is Fg1 for FT-IR measurement of a first surface of the water-soluble film by ATR technique, Fd1 and Fg1 are Fd1≤0.65 and Fd1/Fg1<1. Fd1 is preferably Fd1≥0.25.

Provided are a water-soluble film preferably used for production of a package that has excellent surface gloss and has excellent anti-blocking properties, and a package using the same. A water-soluble film includes a polyvinyl alcohol resin, wherein the water-soluble film has a glossy surface with an average height SRc(G) of 1.8 μm or less and a maximum height SRz(G) of 20 μm or more and 50 μm or less.

A water-soluble film is provided that is capable of achieving deformation resistance during pouch storage as well as excellent water solubility of the film and excellent reduction in undissolved residues. A water-soluble film includes a polyvinyl alcohol-based resin, wherein a crystal long period Ds obtained from an X-ray profile obtained by small-angle X-ray scattering measurement in a water/methanol mixed solvent (volume ratio: 2/8) is from 10.0 to 30.0 nm and a rate of increase (DS−Da)/Da of the crystal long period Ds to a crystal long period Da obtained by small-angle X-ray scattering measurement before immersion in the solvent is 30% or more and 130% or less.

Water-soluble film and packaging material

The present invention provides a monolayer base film for hydraulic transfer printing that is excellent in water solubility and allows high resolution transfer printing without rupture even in high speed printing and a film for hydraulic transfer printing using the same. The present invention is a base film for hydraulic transfer printing comprising a polyvinyl alcohol resin, the base film forming a printing layer to be transferred to an article by hydraulic transfer printing. In this base film for hydraulic transfer printing, the base film for hydraulic transfer printing has an amount (A1) of crystalline component of 60% or less and an amount (A2) of constrained amorphous component from 10% to 50%, the amounts being obtained from a spin-spin relaxation curve byH pulse NMR measurement of the base film in deuterated methanol, and a moisture content from 1 to 5 mass %.

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Okayama, Japan

Sayaka Shimizu