WATER-SOLUBLE PACKAGING FILM

Abstract

The present invention provides a water-soluble packaging film which is capable of inhibiting roll contamination, which has favorable unwinding properties to pass through processing steps smoothly, thereby improving the productivity, and which has enhanced water solubility, chemical resistance, visibility, and packaging properties. The present invention relates to a water-soluble packaging film including: polyvinyl alcohol; a plasticizer; and starch, the starch being applied to a front surface and a rear surface of the water-soluble packaging film, the starch being applied in an amount of 0.001 to 0.10 g per 1 m.sup.2 of the water-soluble packaging film, the water-soluble packaging film having a contact angle with distilled water measured by the sessile-drop method of 20° to 50°.

Claims

1. A water-soluble packaging film comprising: polyvinyl alcohol; a plasticizer; and starch, the starch being applied to a front surface and a rear surface of the water-soluble packaging film, the starch being applied in an amount of 0.001 to 0.10 g per 1 m.sup.2 of the water-soluble packaging film, the water-soluble packaging film having a contact angle with distilled water measured by the sessile-drop method of 20° to 50°.

2. The water-soluble packaging film according to claim 1, wherein the polyvinyl alcohol has a saponification degree of 80 to 99.9 mol %.

3. The water-soluble packaging film according to claim 1, wherein the polyvinyl alcohol has a standard deviation (σ) of saponification degree distribution of 0.1 to 1.0 mol %.

4. The water-soluble packaging film according to claim 1, wherein the polyvinyl alcohol in a 4% by weight aqueous solution has a viscosity measured at 20° C. of 5 to 35 mPa.Math.s.

5. The water-soluble packaging film according to claim 1, wherein the water-soluble packaging film has an orientation of 0.5 to 9.9 nm.

6. The water-soluble packaging film according to claim 2, wherein the polyvinyl alcohol has a standard deviation (σ) of saponification degree distribution of 0.1 to 1.0 mol %.

7. The water-soluble packaging film according to claim 2, wherein the polyvinyl alcohol in a 4% by weight aqueous solution has a viscosity measured at 20° C. of 5 to 35 mPa.Math.s.

8. The water-soluble packaging film according to claim 3, wherein the polyvinyl alcohol in a 4% by weight aqueous solution has a viscosity measured at 20° C. of 5 to 35 mPa.Math.s.

9. The water-soluble packaging film according to claim 6, wherein the polyvinyl alcohol in a 4% by weight aqueous solution has a viscosity measured at 20° C. of 5 to 35 mPa.Math.s.

10. The water-soluble packaging film according to claim 2, wherein the water-soluble packaging film has an orientation of 0.5 to 9.9 nm.

11. The water-soluble packaging film according to claim 3, wherein the water-soluble packaging film has an orientation of 0.5 to 9.9 nm.

12. The water-soluble packaging film according to claim 6, wherein the water-soluble packaging film has an orientation of 0.5 to 9.9 nm.

13. The water-soluble packaging film according to claim 4, wherein the water-soluble packaging film has an orientation of 0.5 to 9.9 nm.

14. The water-soluble packaging film according to claim 7, wherein the water-soluble packaging film has an orientation of 0.5 to 9.9 nm.

15. The water-soluble packaging film according to claim 8, wherein the water-soluble packaging film has an orientation of 0.5 to 9.9 nm.

16. The water-soluble packaging film according to claim 9, wherein the water-soluble packaging film has an orientation of 0.5 to 9.9 nm.

Description

DESCRIPTION OF EMBODIMENTS

[0092] Embodiments of the present invention are further specifically described in the following with reference to, but not limited to, examples.

EXAMPLE 1

[0093] An amount of 90 parts by weight of pyrrolidone ring-modified polyvinyl alcohol (polymerization degree: 1000, saponification degree: 95.8 mol %, standard deviation of saponification degree distribution: 0.21 mol %, modification amount with pyrrolidone ring: 4 mol %, viscosity of 4% by weight aqueous solution: 10 mPa.Math.s) having a structure unit represented by the formula (1) as polyvinyl alcohol, and 5.0 parts by weight of glycerin (Wako Pure Chemical Industries, Ltd.) and 5.0 parts by weight of trimethylolpropane (Wako Pure Chemical Industries, Ltd.) as plasticizers were dissolved in 667 parts by weight of water to prepare a 15% by weight aqueous solution.

[0094] The standard deviation of saponification degree distribution of the polyvinyl alcohol was measured as follows.

(Measurement of Standard Deviation of Saponification Degree Distribution)

[0095] Forty polyvinyl alcohol particles were randomly selected, and the acetyl group content of the polyvinyl alcohol was measured with a FT-IR spectrophotometer (produced by Shimadzu Corporation, IRAffinity-1) by ATR method. Based on the measured acetyl group content, the saponification degree of each particle was determined. Based on variations of the obtained saponification degrees, the standard deviation (σ) of saponification degree distribution was calculated.

[0096] The obtained PVA aqueous solution was applied to a polyethylene terephthalate (PET) film (thickness: 50 μm) as a support member with a lip coater, dried at 70° C. for 10 minutes and then at 110° C. for 10 minutes, and wound on a paper core (inner diameter: 3 inches) to prepare a wound body of a laminated film including a PVA film (thickness: 50 μm) laminated on a support member. The support member was peeled off from the obtained wound body of a laminated film to prepare a PVA film. Starch derived from sweet potato (average particle size: 20 μm, produced by Wako Pure Chemical Industries, Ltd.) was applied to the front surface and the rear surface of the PVA film by a powder spray device (produced by Nikka Ltd., “K-III”) in such a manner that the amount of the applied starch was 0.07 g per 1 m.sup.2 of a water-soluble packaging film to be obtained. A water-soluble packaging film was thus obtained.

EXAMPLE 2

[0097] An amount of 95.1 parts by weight of unmodified polyvinyl alcohol (polymerization degree: 1300, saponification degree: 88.0 mol %, standard deviation of saponification degree distribution: 0.73 mol %, viscosity of 4% by weight aqueous solution: 14 mPa.Math.s) as polyvinyl alcohol, and 3.3 parts by weight of glycerin (Wako Pure Chemical Industries, Ltd.), 0.8 parts by weight of trimethylolpropane (Wako Pure Chemical Industries, Ltd.), and 0.8 parts by weight of Polyethylene Glycol 600 (Wako Pure Chemical Industries, Ltd.) as plasticizers were dissolved in 667 parts by weight of water to prepare a 15% by weight aqueous solution.

[0098] A wound body of a laminate film including a PVA film (thickness: 50 μm) was produced in the same manner as in Example 1. The support member was peeled off from the obtained wound body of a laminated film to prepare a PVA film. A water-soluble packaging film was obtained in the same manner as in Example 1 by applying starch derived from corn (average particle size: 20 μm, Wako Pure Chemical Industries, Ltd.) to the front surface and the rear surface of the PVA film in such a manner that the amount of the applied starch was 0.005 g per 1 m.sup.2 of the water-soluble packaging film.

EXAMPLE 3

[0099] A water-soluble packaging film was prepared in the same manner as in Example 1, except that the polyvinyl alcohol used was sodium sulfonate-modified polyvinyl alcohol A (polymerization degree: 1200, saponification degree: 95.4 mol %, standard deviation of saponification degree distribution: 0.31 mol %, modification amount with sulfonic acid group: 4 mol %, viscosity of 4% by weight aqueous solution: 12 mPa.Math.s) having a structure unit represented by the formula (2) in which R.sup.1 represents a 2-methylenepropylene group, and that starch derived from corn (average particle size: 20 μm) was applied in an amount of 0.01 g per 1 m.sup.2 of the water-soluble packaging film.

EXAMPLE 4

[0100] A water-soluble packaging film was prepared in the same manner as in Example 1, except that the polyvinyl alcohol used was amino group-modified polyvinyl alcohol (polymerization degree: 600, saponification degree: 91.8 mol %, standard deviation of saponification degree distribution: 0.28 mol %, modification amount with amino group: 8 mol %, viscosity of 4% by weight aqueous solution: 6 mPa.Math.s) having a structure unit represented by the formula (3) in which R.sup.2 represents a single bond, and that starch derived from sweet potato (average particle size: 10 μm, Wako Pure Chemical Industries, Ltd.) was applied in an amount of 0.01 g per 1 m.sup.2 of the water-soluble packaging film.

EXAMPLE 5

[0101] A water-soluble packaging film was prepared in the same manner as in Example 1, except that the polyvinyl alcohol used was carboxylic acid-modified polyvinyl alcohol (Kuraray Co., Ltd., KL-118, polymerization degree: 1700, saponification degree: 97.5 mol %, standard deviation of saponification degree distribution: 0.25 mol %, modification amount with carboxyl group: 1.5 mol %, viscosity of 4% by weight aqueous solution: 30 mPa.Math.s) having a structure unit represented by the formula (4-2) in which R.sup.3 represents a methylene group, and X.sup.2 and X.sup.3 each represent a sodium atom, and that starch derived from sweet potato (average particle size: 30 μm, Wako Pure Chemical Industries, Ltd.) was applied in an amount of 0.01 g per 1 m.sup.2 of the water-soluble packaging film.

EXAMPLE 6

[0102] A water-soluble packaging film was prepared in the same manner as in Example 1, except that the polyvinyl alcohol used was sodium sulfonate-modified polyvinyl alcohol B (polymerization degree: 1200, R.sup.1═CH.sub.2, saponification degree: 90.1 mol %, standard deviation of saponification degree distribution: 0.98 mol %, modification amount with sulfonic acid group: 4 mol %, viscosity of 4% by weight aqueous solution: 10 mPa.Math.s) having a structure unit represented by the formula (2), and that the starch derived from sweet potato (average particle size: 30 μm, Wako Pure Chemical Industries, Ltd.) was applied in an amount of 0.01 g per 1 m.sup.2 of the water-soluble packaging film.

EXAMPLE 7

[0103] An amount of 90 parts by weight of unmodified polyvinyl alcohol (polymerization degree: 1300, saponification degree: 98.0 mol %, standard deviation of saponification degree distribution: 0.18 mol %, viscosity of 4% by weight aqueous solution: 17 mPa.Math.s), and 5.0 parts by weight of glycerin (Wako Pure Chemical Industries, Ltd.) and 5.0 parts by weight of trimethylolpropane (Wako Pure Chemical Industries, Ltd.) as plasticizers were dissolved in 667 parts by weight of water to prepare a 15% by weight aqueous solution.

[0104] The obtained PVA aqueous solution was applied to a polyethylene terephthalate (PET) film (thickness: 50 μm) as a support member with an auto film applicator (produced by Tester Sangyo Co., Ltd., “PI-1210”), and dried at 80° C. for 20 minutes to produce a PVA film (thickness: 50 μm) on the support member. After removal of the support member from the obtained PVA film, the resulting water-soluble packaging film was exposed to an environment at a temperature of 23° C. and a relative humidity of 50% RH for 24 hours.

[0105] Then, the water-soluble packaging film was cut to a size of 600 mm×500 mm and set on a tensile tester such that the width of the film was 500 mm. After stretching of the film to the width of 900 mm (stretch ratio: 1.8 times), starch derived from sweet potato (average particle size: 30 μm, Wako Pure Chemical Industries, Ltd.) was applied to the front surface and the rear surface of the PVA film in an amount of 0.01 g per 1 m.sup.2of a water-soluble packaging film to be obtained. A water-soluble packaging film was thus prepared.

EXAMPLE 8

[0106] A water-soluble packaging film was prepared in the same manner as in Example 1, except that the starch derived from sweet potato (average particle size: 20 μm, Wako Pure Chemical Industries, Ltd.) was changed to starch derived from tapioca (average particle size of 20 μm, Gaban Co., Ltd.).

COMPARATIVE EXAMPLE 1

[0107] An amount of 91 parts by weight of sodium sulfonate-modified polyvinyl alcohol (polymerization degree: 1200, saponification degree: 95.4 mol %, standard deviation of saponification degree distribution: 0.31 mol %, modification amount with sulfonic acid group: 4 mol %, viscosity of 4% by weight aqueous solution: 12 mPa.Math.s) having a structure unit represented by the formula (2) in which R.sup.1 represents a 2-methylenepropylene group as polyvinyl alcohol, and 4.0 parts by weight of glycerin (Wako Pure Chemical Industries, Ltd.), 3.0 parts by weight of trimethylolpropane (Wako Pure Chemical Industries, Ltd.), and 2.0 parts by weight of Polyethylene Glycol 600 (Wako Pure Chemical Industries, Ltd.) as plasticizers were dissolved in 667 parts by weight of water to prepare a 15% by weight aqueous solution.

[0108] A wound body of a laminated film including a PVA film (thickness: 50 μm) was produced in the same manner as in Example 1. The support member was peeled off from the obtained wound body of a laminated film to prepare a water-soluble packaging film.

COMPARATIVE EXAMPLE 2

[0109] A water-soluble packaging film was produced in the same manner as in Example 2, except that the starch derived from corn (average particle size: 20 μm) was applied in an amount of 0.11 g per 1 m.sup.2 of the water-soluble packaging film.

COMPARATIVE EXAMPLE 3

[0110] A water-soluble packaging film was produced in the same manner as in Example 2, except that the starch derived from sweet potato (average particle size: 30 μm) was applied in an amount of 0.0001 g per 1 m.sup.2 of the water-soluble packaging film.

COMPARATIVE EXAMPLE 4

[0111] The water-soluble packaging film obtained in Comparative Example 1 was embossed in a lattice pattern to give a water-soluble packaging film having a thickness at a recess of 17 μm, a height difference between a recess and a projection of 30 μm, a groove width of 0.1 mm, and a groove interval of 0.1 mm.

COMPARATIVE EXAMPLE 5

[0112] An amount of 95.05 parts by weight of unmodified polyvinyl alcohol (polymerization degree: 1300, saponification degree: 88.0 mol %, standard deviation of saponification degree distribution: 0.73 mol %, viscosity of 4% by weight aqueous solution: 14 mPa.Math.s) as polyvinyl alcohol, 3.3 parts by weight of glycerin (Wako Pure Chemical Industries, Ltd.), 0.8 parts by weight of trimethylolpropane (Wako Pure Chemical Industries, Ltd.), and 0.8 parts by weight of Polyethylene Glycol 600 (Wako Pure Chemical Industries, Ltd.) as plasticizers, and 0.05 parts by weight of starch derived from corn (average particle size: 20 μm, Wako Pure Chemical Industries, Ltd.) were dissolved in 667 parts by weight of water to prepare a 15% by weight aqueous solution.

[0113] In the same manner as in Example 1, a wound body of a laminated film including a PVA film (thickness: 50 μm) was prepared. The support member was peeled off from the obtained wound body of a laminated film to prepare a water-soluble packaging film. The obtained water-soluble packaging film contained starch inside thereof, and no deposition of the starch on the film surface was observed.

COMPARATIVE EXAMPLE 6

[0114] An amount of 100 parts by weight of unmodified polyvinyl alcohol (polymerization degree: 1300, saponification degree: 88.0 mol %, standard deviation of saponification degree distribution: 0.73 mol %, viscosity of 4% by weight aqueous solution: 14 mPa.Math.s) as polyvinyl alcohol was dissolved in 667 parts by weight of water to prepare a 15% by weight aqueous solution.

[0115] A wound body of a laminated film including a PVA film (thickness: 50 μm) was prepared in the same manner as in Example 1. The support member was peeled off from the obtained wound body of a laminated film to prepare a water-soluble packaging film.

COMPARATIVE EXAMPLE 7

[0116] A water-soluble packaging film was prepared in the same manner as in Comparative Example 6, except that starch derived from sweet potato (average particle size: 20 μm) was applied to the front surface and the rear surface of the PVA film in an amount of 0.01 g per 1 m.sup.2 of the water-soluble packaging film.

COMPARATIVE EXAMPLE 8

[0117] A water-soluble packaging film was produced in the same manner as in Example 1, except that the starch derived from sweet potato (average particle size: 20 μm, Wako Pure Chemical Industries, Ltd.) was changed to rosin (average particle size: 20 μm, MIKASA CORPORATION).

TABLE-US-00001 TABLE 1 Composition of polyvinyl alcohol aqueous solution Polyvinyl alcohol resin Amount Viscosity Standard deviation of of 4 wt % Amount Saponification of saponification modifying aqueous added Polymerization degree degree distribution group solution (parts by degree (mol %) σ (mol %) Modifying group (mol %) (mPa .Math. s) weight) Example 1 1000 95.8 0.21 Pyrrolidone ring group 4 10 90 Example 2 1300 88.0 0.73 — — 14 95.1 Example 3 1200 95.4 0.31 Sulfonic acid group 4 12 90 Example 4 600 91.8 0.28 Amino group 8 6 90 Example 5 1700 97.5 0.25 Carboxyl group 1.5 30 90 Example 6 1200 90.1 0.98 Sulfonic acid group 4 10 90 Example 7 1300 98.0 0.18 — — 17 90 Example 8 1000 95.8 0.21 Pyrrolidone ring group 4 10 90 Comparative 1200 95.4 0.31 Sulfonic acid group 4 12 91 Example 1 Comparative 1300 88.0 0.73 — — 14 95.1 Example 2 Comparative 1300 88.0 0.73 — — 14 95.1 Example 3 Comparative 1200 95.4 0.31 Sulfonic acid group 4 12 91 Example 4 Comparative 1300 88.0 0.73 — — 14 95.05 Example 5 Comparative 1300 88.0 0.73 — — 14 100 Example 6 Comparative 1300 88.0 0.73 — — 14 100 Example 7 Comparative 1000 95.8 0.21 Pyrrolidone ring group 4 10 90 Example 8 Composition of polyvinyl alcohol aqueous solution Applied starch Plasticizer (parts by weight) Starch Stretch Application Trimethylol Polyethylene (parts by ratio amount Glycerin propane glycol 6000 weight) (times) Kind (g/m.sup.2) Example 1 5.0 5.0 — — 1 Derived from sweet potato 0.07 Example 2 3.3 0.8 0.8 — 1 Derived from corn 0.005 Example 3 5.0 5.0 — — 1 Derived from corn 0.01 Example 4 5.0 5.0 — — 1 Derived from sweet potato 0.01 Example 5 5.0 5.0 — — 1 Derived from sweet potato 0.01 Example 6 5.0 5.0 — — 1 Derived from sweet potato 0.01 Example 7 5.0 5.0 — — 1.8 Derived from sweet potato 0.01 Example 8 5.0 5.0 — — 1 Derived from tapioca 0.07 Comparative 4.0 3.0 2.0 — 1 — 0 Example 1 Comparative 3.3 0.8 0.8 — 1 Derived from corn 0.11 Example 2 Comparative 3.3 0.8 0.8 — 1 Derived from sweet potato 0.0001 Example 3 Comparative 4.0 3.0 2.0 — 1 — 0 Example 4 Comparative 3.3 0.8 0.8 0.05 1 — 0 Example 5 Comparative 0 0 0 — 1 — 0 Example 6 Comparative 0 0 0 — 1 Derived from sweet potato 0.01 Example 7 Comparative 5.0 5.0 — — 1 Rosin 0.07 Example 8

(Evaluation)

[0118] The films obtained in the examples and comparative examples were evaluated for the following parameters. Table 2 shows the results.

(1) Contact Angle

[0119] The obtained water-soluble packaging film was cut to a size of 10 mm×30 mm. The obtained film piece was exposed to an environment at 50° C. for 24 hours, and then attached to a glass substrate. Then, about 5.0 μL of distilled water was dripped on the water-soluble packaging film, and an angle formed by the water-soluble packaging film and a tangent to the droplet was measured after one second from the drip by the sessile-drop method using a contact angle measurement apparatus “Theta lite” (Biolin Scientific Holding AB.) in an atmosphere at 23° C. and 50% RH.

(2) Roll Contamination

[0120] A wound body (50 mm width) of the obtained water-soluble packaging film was rewound on a metal roll for 50 m at a rewinding rate of 20 m/min in conformity with JIS 20237. The metal roll was run a finger, and whether the starch applied to the water-soluble packaging film was deposited on the metal roll was visually observed. Evaluation was performed based on the following criteria.

[0121] In the case of the water-soluble packaging film obtained in Comparative Example 1, the film was adhered to the metal roll during the conveyance, and therefore, observation of the roll contamination could not be performed. [0122] ∘∘ (Excellent): No deposition of starch was observed. [0123] ∘ (Good): Deposition of starch was slightly observed. [0124] × (Poor): Starch was deposited to the extent that the finger get white upon contact with the roll, or observation could not be performed.

(3) Unwinding Properties

[0125] The obtained water-soluble packaging film was cut to a size of 80 mm×200 mm. The friction coefficient between the water-soluble packaging films was measured in conformity with JIS K7125 and evaluated based on the following criteria. [0126] ∘∘ (Excellent): Less than 0.8. [0127] ∘ (Good): 0.8 or more but less than 1.8. [0128] × (Poor): 1.8 or more.

(4) Visibility

[0129] The haze of the obtained water-soluble packaging film was measured with a haze meter (produced by Tokyo Denshoku Co., Ltd., TC-H3DPK) at 20° C., and evaluated based on the following criteria. [0130] ∘ (Good): Haze of less than 3.5%. [0131] × (Poor): Haze of 3.5% or more.

(5) Visibility After Durability Test

[0132] The obtained water-soluble packaging film was formed into a bag in a size of 5 cm×4 cm and allowed to contain 20 g of sodium trichloroisocyanurate therein. The bag was further put into an aluminum bag and sealed therein. The obtained bag was left in a constant temperature/humidity oven at a temperature of 40° C. and a humidity of 70% RH for a month. Then, the film portion was cut out from the bag, and the haze thereof was measured with a haze meter (produced by Tokyo Denshoku Co., Ltd., TC-H3DPK) at 20° C. The obtained haze was evaluated based on the following criteria. [0133] ∘ (Good): Haze was less than 3.5%. [0134] × (Poor): Haze was 3.5% or more.

(6) Water Solubility (Dissolution Time)

[0135] The support member was peeled off from the obtained laminated film to prepare a water-soluble packaging film. The obtained water-soluble packaging film was exposed to an environment at a temperature of 23° C. and a relative humidity of 50% RH for 24 hours.

[0136] Then, the water-soluble packaging film was cut to a size of 35 mm×40 mm, and the obtained film piece was fixed to a jig. The film fixed to the jig was immersed in water (500 ml) in a 500-ml beaker under stirring (in such a manner that the bottom of a vortex reaches the metering line of 400 ml) with a stirrer while the water temperature was maintained at 23° C. The time until residues of the film was not any more observed on the jig was measured, and evaluated based on the following criteria. [0137] ∘∘ (Excellent): Shorter than 20 seconds. [0138] ∘ (Good): 20 seconds or longer but shorter than 30 seconds. [0139] × (Poor): 30 seconds or longer.

(7) Long-Term Storability

[0140] The support member was peeled off from the obtained laminated film to prepare a water-soluble packaging film. The obtained packaging film was put into an aluminum zipper bag and left to stand in an environment at a temperature of 23° C. and a relative humidity of 50% RH for a month.

[0141] Then, the water-soluble packaging film was taken out and visually observed to check the presence of bleeding of the plasticizer or the additives from the film after the standing for a month. Evaluation was performed based on the following criteria. [0142] ∘ (Good): Film was transparent and had no bleeding therefrom. [0143] × (Poor): Film was turbid and had bleeding therefrom.

(8) Orientation

[0144] The obtained water-soluble packaging film was exposed to an environment at a temperature of 23° C. and a relative humidity of 50% RH for 24 hours. Then, a phase difference R of the water-soluble packaging film was measured with a phase difference measuring apparatus (KOBRA-WR, produced by Oji Scientific Instruments) at an incident angle of 45°, and the numerical value of the measured phase difference R was taken as the value of the orientation.

(9) Packaging Properties

[0145] The obtained water-soluble packaging film was formed into bags in a size of 5 cm×4 cm. The bags were each allowed to contain 20 g of powder detergent and heat-sealed at 150° C. One hundred bags were left in a constant temperature/humidity oven at a temperature of 40° C. and a humidity of 70% RH for a month. Then, the sealing state of the water-soluble packaging film was visually observed. [0146] ∘ (Good): Defective sealing was observed in one or less bag. [0147] × (Poor): Defective sealing was observed in two or more bags.

(10) Chemical Resistance

[0148] The obtained water-soluble packaging film was formed into a bag in a size of 5 cm×4 cm, and the bag was allowed to contain 20 g of sodium trichloroisocyanurate. The bag was further put into an aluminum bag and sealed. The resulting bag was left in a constant temperature/humidity oven at a temperature of 40° C. and a humidity of 70% RH for a month. Then, the appearance of the water-soluble packaging film was visually observed. [0149] ∘ (Good): The appearance was not changed. [0150] × (Poor): The appearance was colored yellow or brown.

TABLE-US-00002 TABLE 2 Evaluation Visibility Unwinding after durability test Contact properties Change in angle Roll Friction Visibility Haze haze (°) contamination coefficient Evaluation Haze Evaluation (%) (%) Evaluation Example 1 24.0 ◯ 0.5 ◯◯ 2.5 ◯ 2.6 4.0 ◯ Example 2 48.0 ◯◯ 1.6 ◯ 3 ◯ 3.4 13.3 ◯ Example 3 31.5 ◯◯ 0.7 ◯◯ 2.4 ◯ 2.5 4.2 ◯ Example 4 37.5 ◯◯ 1.2 ◯ 3.1 ◯ 3.2 3.1 ◯ Example 5 33.1 ◯◯ 0.9 ◯ 3.0 ◯ 3.1 3.3 ◯ Example 6 30.7 ◯◯ 0.6 ◯◯ 3.0 ◯ 3.2 6.7 ◯ Example 7 48.5 ◯◯ 1.5 ◯ 2.6 ◯ 2.8 7.7 ◯ Example 8 25.8 ◯ 0.6 ◯◯ 2.6 ◯ 2.7 3.8 ◯ Comparative 13.3 Not evaluable 2.8 X 2.3 ◯ 2.4 4.3 ◯ Example 1 Comparative 13.3 X 0.2 ◯◯ 2.9 ◯ 3.4 17.2 ◯ Example 2 Comparative 59.0 ◯◯ 1.9 X 2.7 ◯ 3.3 22.2 ◯ Example 3 Comparative 13.3 ◯◯ 0.7 ◯◯ 67.5 X 67.7 0.3 X Example 4 Comparative 59.7 ◯◯ 2.1 X 3.2 ◯ 3.4 6.3 ◯ Example 5 Comparative 53.0 ◯◯ 0.4 ◯◯ 2.2 ◯ 3.2 45.5 ◯ Example 6 Comparative 50.8 ◯ 0.3 ◯◯ 2.3 ◯ 3.2 39.1 ◯ Example 7 Comparative 23.1 X 0.9 ◯ 4.4 X 4.5 2.3 X Example 8 Evaluation Long-term Water solubility storability Packaging properties Dissolution Evaluation Number of time on Orientation defective Chemical resistance (sec.) Evaluation appearance (nm) sealing Evaluation Appearance Evaluation Example 1 28 ◯ ◯ 1.0 0 ◯ No change ◯ Example 2 24 ◯ ◯ 1.2 0 ◯ No change ◯ Example 3 18 ◯◯ ◯ 0.8 0 ◯ No change ◯ Example 4 19 ◯◯ ◯ 0.7 1 ◯ No change ◯ Example 5 23 ◯ ◯ 1.0 0 ◯ No change ◯ Example 6 14 ◯◯ ◯ 1.0 0 ◯ No change ◯ Example 7 14 ◯◯ ◯ 9.7 0 ◯ No change ◯ Example 8 27 ◯ ◯ 1.0 0 ◯ No change ◯ Comparative 20 ◯ ◯ 5.0 0 ◯ No change ◯ Example 1 Comparative 26 ◯ ◯ 1.2 0 ◯ No change ◯ Example 2 Comparative 25 ◯ ◯ 1.2 0 ◯ No change ◯ Example 3 Comparative 20 ◯ ◯ 4.8 0 ◯ No change ◯ Example 4 Comparative 26 ◯ ◯ 1.3 1 ◯ No change ◯ Example 5 Comparative 61 X ◯ 1.3 0 ◯ No change ◯ Example 6 Comparative 60 X ◯ 1.2 0 ◯ No change ◯ Example 7 Comparative 39 X ◯ 1.0 0 ◯ No change ◯ Example 8

INDUSTRIAL APPLICABILITY

[0151] The present invention can provide a water-soluble packaging film which is capable of inhibiting roll contamination, which has favorable unwinding properties to pass through processing steps smoothly, thereby improving the productivity, and which has enhanced water solubility, chemical resistance, visibility, and packaging properties.