Conventionally, a packaging material using a PVA film has been widely used as a material for containing agricultural chemicals, medicines, dyes, detergents, fertilizers, cosmetics, sanitary products and the like. This packaging material is used for, for example, obtaining a solution of what is included in the container utilizing the water solubility of PVA, by directly casting the container into an aqueous medium to allow disintegration, dispersion or dissolution of the container, for the disposal of the packaging material opened when in use, by dumping the packaging material into water as it is, and for other purposes. However, because the PVA film absorbs moisture, the surface sometimes becomes sticky and tends to show blocking of film due to the adhesive property of the film in high humidity.
To prevent the blocking property, films are generally embossed. For example, an embossed water soluble film has been proposed, which has a thickness of a concave part of 15-25 μm, and a tensile strength of the film of 2.5-4.5 kg/mm2 (JP-A-7-290567).
While the above-mentioned film shows improved dispersibility and dissolution in water, mechanical strength and the like, it is otherwise with regard to resistance to blocking, appearance to impart an impression of high quality, resistance to pinholes and the like and these aspects have not been considered sufficiently.
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