Water-soluble film and packaging

Abstract

To provide: a water-soluble film that has excellent peelability from a support when produced and that also has excellent transparency and sealing properties; a drug packaging that uses the water-soluble film; and a production method for a water-soluble film that has the abovementioned excellent characteristics. A water-soluble film that contains a polyvinyl alcohol resin, wherein the fluorine fraction (F1S) of all elements as found by analyzing a first surface of the water-soluble film by x-ray photoelectron spectroscopy is 1 to 25 mol%, and the fluorine fraction (F1B) of all elements as found by analyzing a plane that is at a depth of 0.1 [mu]m from the first surface by x-ray photoelectron spectroscopy is no more than 0.5 mol%.

Description

technical field [0001] The present invention relates to a polyvinyl alcohol resin-containing water-soluble film suitable for packaging various medicines, and a package using the same. Background technique [0002] Conventionally, water-soluble films have been widely used in various chemicals such as detergents and agricultural chemicals, and packages containing seeds, and the demand has been increasing due to their simplicity. [0003] As a water-soluble film used for this purpose, a PVA film mainly composed of a polyvinyl alcohol resin (hereinafter, sometimes referred to as PVA) is widely used. In order to improve various physical properties of the PVA film, various techniques have been proposed. For example, a water-soluble film having improved water solubility by blending various additives such as a plasticizer or using modified PVA has been proposed (for example, Patent Document 1). [0004] The water-soluble film disclosed in Patent Document 1 improves water solubilit...

AI Technical Summary

Problems solved by technology

[0012] However, in the technology of Patent Document 2, it is necessary to use a large amount of fluorine-containing surfactants, and it is difficult to cope with environmental pollution caused by halogen substances that has become a problem in recent years.

Moreover, the affinity between hydrophobic fluorine-containing substances and PVA is low, so it causes phase separation in the film, which easily impairs the transparency of the film.

Moreover, when this technology is applied to water-soluble films, if the film contains more fluorine-containing surfactants, sealing between films based on water and / or heat is carried out after packaging the contents (hereinafter, sometimes When it is called a seal), a poor seal often occurs and the contents leak from the seal

[0013] On the other hand, if the technology of Patent Document 3 is applied to a water-soluble film, the water-soluble film tends to stick to each other due to moisture absorption compared with the optical film, and the film is prone to adhesion between the films when the roll is unwound, etc. Wrinkles or breaks due to friction

In addition, forming a strong fluororesin layer on a support such as a roller or a conveyor belt is also likely to increase the cost from the viewpoint of maintenance of the material surface and the support.

Images