JP2001354789A - Polylactic acid resin film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polylactic acid resin film having properties balanced among antistatic, sliding, and anti-block property to enhance the high speed traveling properties on an adhering machine for the window of a mailing envelope. SOLUTION: The polylactic acid resin film has a coating film composed of a coating composition comprising 85-10 wt.% polyether modified silicone and 15-90 wt.% polyoxyethylene alkylamine formed at least at one side of the film.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface treatment of a biodegradable film mainly composed of a polylactic acid-based resin, and more particularly to a polylactic acid-based resin film suitable for application to an envelope window. It is.

[0002]

2. Description of the Related Art Synthetic polymer compounds have come to be widely used as plastics due to their excellent properties.
How to treat this waste plastic is a major social problem. When incinerated, there is a problem that the incinerator is easily damaged due to a large amount of generated heat and may generate harmful substances, and there is a problem that the incinerator remains in the environment forever because it does not rot even when buried. Furthermore, it is difficult to disseminate recycling as soon as possible, considering the costs of separation, collection, and regeneration.

In order to reduce the burden on the environment and to make society more sustainable, biodegradable plastics that decompose in the natural environment after disposal are required to cope with the increasing environmental problems. It has become. Known biodegradable plastics include starch-based resins, aliphatic polyester resins produced by microorganisms, aliphatic polyester resins produced by chemical synthesis, and resins of a type in which their chemical structures are partially modified. Biodegradable aliphatic aromatic polyester resins and the like are known.

[0004] Among these biodegradable plastics, polylactic acid-based resins are superior in transparency, rigidity and processability to other biodegradable plastics.
Since it is strong and excellent in transparency, it is suitable as a film for packaging various types and a film for attaching envelope windows. On the other hand, in the application of resin films, the processing speed has been increased due to the progress of processing machines. Taking the window application of a film on an envelope as an example, what has been conventionally performed the window application of the envelope at a processing speed of 400 to 600 sheets / min has recently been improved to 800 to 1000 sheets / minute due to the progress of the window application machine. Min, and more than 1000 sheets / min., And the running speed of the film is becoming higher. Along with this, the demands for films such as antistatic properties, slipperiness and anti-blocking properties are becoming more and more strict in order to obtain machine suitability and processability corresponding to higher processing speeds. It is the current situation.

In the thermoplastic resin film for an envelope window disclosed in JP-A-10-11978, an anionic surfactant such as a sulfonate and a cationic resin such as a quaternary ammonium salt are mainly added to a styrene resin film. Surfactants, amphoteric surfactants such as betaine-type surfactants, and nonionic surfactants such as fatty acid amides are applied to impart antistatic properties, and in the step of applying a film window to an envelope, It is described that film clogging, wrinkling, and defective bonding position can be eliminated, and the film can be bonded at high speed. However, when the half-life of the charge decay described in Japanese Patent Application Laid-Open No. H10-11978 is about 200 seconds or 150 seconds, the antistatic property is insufficient, and when the window is attached to an envelope at high speed, Since the charge amount of the film becomes large, there is a case where the film is clogged with a machine or the sticking position is shifted. Practically, unless the half-life of the charge decay is less than 60 seconds as an antistatic property, it cannot be said that the film is suitable for attaching to an envelope window.

In the study of the present inventors, in order to reduce the half life of the charge decay to 60 seconds or less, a surfactant having a high HLB value (hydrophilic-lipophilic balance), that is, a highly hydrophilic surfactant is used. And the amount of application to the film must be increased. As a result, there is an adverse effect that the blocking phenomenon in which the films are firmly adhered to each other in the roll easily occurs due to the moisture absorption of the applied surfactant. The blocking phenomenon is particularly remarkable under high temperature and high humidity conditions in the summer, and the film is unwound from the roll. ,
The problem that stable operation cannot be performed occurs.

On the other hand, a method of adding or coating fine particles of an inorganic compound or an organic compound to a polymer for the purpose of imparting an anti-blocking property is known. A styrene resin film containing a king agent is disclosed in
No. 9978 discloses the application of silicon dioxide particles together with an antistatic agent. By the method of adding or applying these fine particles, it is possible to impart anti-blocking property and improve the slipperiness, but on the other hand, it deteriorates the transparency of the film, or it can be used with various rolls in an envelope processing machine. There is a problem that fine particles fall off from the film surface at the time of friction and stains occur,
Not preferred.

Further, Japanese Patent Application Laid-Open No. H10-11978 discloses a modified silicone surfactant (polyether-modified silicone). Although this modified silicone is modified with a hydrophilic polyether group, it exhibits a surface active effect, that is, an antistatic effect. There is a feature that the problem of blocking does not occur even if the number is increased. However, even when this modified silicone surfactant is used, there is a problem of poor adhesion to paper. In other words, in order to apply the modified silicone-based surfactant and satisfy both the antistatic property and the anti-blocking property, the coating amount on the film should be the aforementioned anionic, cationic, amphoteric or nonionic. It must be higher than general surfactants such as surfactants. In that case, the water repellency becomes too good due to the effect of the low surface tension of the silicone molecules, and it is difficult to use paper with an envelope window pasting machine. In the bonding step, the adhesiveness with the adhesive is deteriorated.
For this reason, a shift in the position of application to the envelope window during the envelope processing is likely to occur. That is, in the case of surface treatment with a modified silicone-based surfactant, an application amount satisfying both the antistatic property and the anti-blocking property is not preferable because adhesion to paper is deteriorated.

Japanese Unexamined Patent Publication (Kokai) No. 10-11978 discloses an example of a combination of a modified silicone surfactant and a fatty acid amide. Balance is not enough. That is, when the modified silicone and the fatty acid amide are applied in combination, the slip property and the anti-blocking property, which are the characteristics of the modified silicone, are impaired, and the antistatic property, which is the characteristic of the fatty acid amide, is not preferable.

The above is the technique applied to a non-biodegradable resin film mainly composed of a styrene-based resin, and no biodegradable resin film is disclosed. Regarding biodegradable resin films, see JP-A-9-22.
No. 1587 discloses an antistatic polylactic acid-based film and sheet containing a nonionic antistatic agent. The films and sheets have biodegradability and antistatic properties, but do not improve slipperiness and antiblocking properties, and do not achieve the object of the present invention.

[0011]

SUMMARY OF THE INVENTION The present invention provides a polylactic acid-based resin film which has biodegradability, balances antistatic properties, slip properties and anti-blocking properties, and has excellent adhesion to paper. The purpose is to:

[0012]

Means for Solving the Problems The present inventors have conducted intensive studies in order to solve the above-mentioned problems, and as a result, surprisingly, by mixing a specific surfactant and a modified silicone compound in a specific ratio, It was found that the object of the present invention could be achieved, and the present invention was completed. That is, the present invention
In films mainly composed of polylactic acid resin,
(A) Polyether-modified silicone: 85 to 10% by weight
And (B) a coating composition comprising a polyoxyethylene alkylamine having a structure represented by the following formula (3): 15 to 90% by weight is coated on at least one surface of the film with 2 to 30% by weight.
A polylactic acid-based resin film having a coating film of mg / m ² .

[0013]

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(Wherein R is an alkyl group having 8 to 22 carbon atoms, x is an integer of 1 to 30, and y is an integer of 1 to 30.) Further, the polyether-modified silicone (A) has the following formula: A polylactic acid-based resin film having the structure of (4).

[0015]

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(Where R is H or a lower alkyl group having 1 to 4 carbon atoms, m is an integer of 0 to 80, n is an integer of 1 to 30, m + n is an integer of 1 to 100, n / (n + m ) = 0.
1-1, a = an integer of 5-30, b = 0 an integer of 0-30, a
+ B = integer of 5 to 60, ratio of a: b is 100: 0 to 5
0:50. Further, on at least one side of the film, the coefficient of dynamic friction between the film and the metal is 0.15 to 0.30, the coefficient of static friction between the films is 0.35 to 0.45, and the charged voltage at 20 ° C. and 20% relative humidity. A polylactic acid-based resin film having a half-life of attenuation of 60 seconds or less.

The present invention will be specifically described below. The film of the present invention mainly comprises a polylactic acid-based resin. The polylactic acid-based resin is a polymer containing 50% by weight or more of a lactic acid monomer unit, such as polylactic acid, a copolymer of lactic acid and another hydroxycarboxylic acid, an aliphatic cyclic ester, or lactic acid. These polymers are compositions containing 50% by weight or more of a monomer. The polylactic acid-based resin,
From the viewpoint of rigidity, the glass transition temperature is 40 ° C. or more and 1
It is preferable to use polylactic acid or a polylactic acid copolymer having a melting point of 00 ° C. or higher.

The lactic acid includes L-lactic acid and D-lactic acid. Examples of the hydroxycarboxylic acid include glycolic acid, 3-hydroxybutyric acid, 4-hydroxybutyric acid, 3-hydroxyvaleric acid, 4-hydroxyvaleric acid, and 6-hydroxycaproic acid. As the aliphatic cyclic ester, glycolide, lactide, β-propiolactone, γ-butyrolactone, δ-valerolactone, ε-
Examples include caprolactone and lactones obtained by substituting these with various groups such as a methyl group.

As the polymerization method for the polylactic acid resin, known methods such as a condensation polymerization method and a ring-opening polymerization method can be employed. Further, a method of increasing the molecular weight by using a binder such as polyisocyanate, polyepoxy compound, acid anhydride and polyfunctional acid chloride can also be used. The weight average molecular weight of the polylactic acid-based resin is preferably in the range of 20,000 to 1,000,000. In the polylactic acid-based resin film of the present invention, in addition to the above resins, known additives such as a heat stabilizer, an antioxidant, and an ultraviolet absorber are compounded within a range that does not impair the requirements and characteristics of the present invention. It is possible to

The polylactic acid-based resin film of the present invention can be obtained by biaxially stretching by a conventionally known stretching method such as an inflation method or a tenter method. The stretching ratio at that time is 1 to 10 times in each of the longitudinal direction and the transverse direction, and from the viewpoint of reinforcement of the film strength by imparting stretching orientation and uniformity of stretching, the range of 1.5 to 5 times is particularly preferable. preferable. However, in the present invention, the stretching ratio is not particularly limited. The film thickness after stretching is preferably 8 to 100 μm, more preferably 15 to 50 μm.
m is not particularly limited in the present invention.

Although the polylactic acid resin film is more hydrophilic than the polyolefin resin film and the polystyrene resin film, in order to uniformly apply the coating composition of the present invention on the surface of the polylactic acid resin film, It is preferable that the surface of the film to be applied is further subjected to a hydrophilic treatment by corona treatment. By this hydrophilic treatment,
The uniformity of the coating film is improved, and the antistatic property and the slip property are efficiently exhibited. The surface tension at that time was 400 μN /
The range is preferably from cm to 600 μN / cm.

The polyether-modified silicone (A) used in the present invention is a dimethyl silicone obtained by partially modifying a methyl group with a polyoxyethylene group and a polyoxypropylene group. From the viewpoints of the antistatic property, slip property and anti-blocking property of the film, the following formula (5) is used.
The structure having the following structure is preferable.

[0023]

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Wherein R is H or a lower alkyl group having 1 to 4 carbon atoms, m is an integer of 0 to 80, n is an integer of 1 to 30, m + n is an integer of 1 to 100, and n / (n + m ) = 0.
1-1, a = an integer of 5-30, b = 0 an integer of 0-30, a
+ B = integer of 5 to 60, ratio of a: b is 100: 0 to 5
0:50. Further, more preferably, in the formula (5), m = 1 to 3
Integer of 0, n / (m + n) = 0.3 to 1, a + b = 5
15. Polyether-modified silicone having a: b ratio of 100: 0.

The polyoxyethylene alkylamine (B) used in the present invention is obtained by an addition reaction between an aliphatic amine having 8 to 22 carbon atoms and ethylene oxide, or a dehydration reaction between the aliphatic amine and polyoxyethylene. Having the structure of the following formula (6).

[0026]

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(Wherein, R is an alkyl group having 8 to 22 carbon atoms, x is an integer of 1 to 30 and y is an integer of 1 to 30). From the viewpoint of the combined effect with the polyether-modified silicone described later, preferably, the aliphatic amine has 8 to 18 carbon atoms, and a saturated aliphatic amine such as laurylamine, myristylamine, and stearylamine is used alone. Or
A polyoxyethylene alkylamine comprising an aliphatic amine which is a mixture of these saturated aliphatic amines and unsaturated aliphatic amines such as oleylamine (eg, higher aliphatic amines derived from coconut oil, tallow, etc.). . Still more preferably, it is a polyoxyethylene alkylamine in which x = 1 to 15 and y = 1 to 15 in the above formula (6).

The coating composition of the present invention improves the dispersibility of the polyether-modified silicone on the surface of the polylactic acid-based resin film by adding a polyoxyethylene alkylamine (B) to the polyether-modified silicone (A). Therefore, the anti-blocking property and the slip property can be efficiently exhibited with a smaller coating amount than when the polyether-modified silicone is used alone. In addition, polyoxyethylene alkylamine has a high antistatic effect on polylactic acid-based resin films among nonionic surfactants, and also has excellent compatibility with polyether-modified silicone as described above. Even when used in combination with the modified silicone, the antistatic effect can be exhibited with a small coating amount without hindering the antistatic property. Surfactants other than the requirements of the present invention can also provide excellent antistatic properties that are not different from those of the polyoxyethylene alkylamine used in the present invention when used alone. When used in combination, the anti-blocking property and the slipperiness characteristic of the polyether-modified silicone may be impaired, or the antistatic property characteristic of the surfactant may be impaired. Cannot be achieved. That is, in the present invention, for the first time by using a polyether-modified silicone and a polyoxyethylene alkylamine having a specific structure in combination, the antistatic properties, the slip properties, and the anti-blocking properties are balanced, and the adhesiveness to paper is also excellent. A polylactic acid-based resin film can be obtained.

The polylactic acid resin film of the present invention comprises 85 to 10% by weight of the polyether-modified silicone (A) and 15% by weight of the polyoxyethylene alkylamine (B).
It can be obtained by applying a coating composition consisting of about 90% by weight to a polylactic acid-based resin film. When the content of the polyether-modified silicone (A) is 10% by weight or more, appropriate slip properties and sufficient anti-blocking properties can be obtained. However, if the polyether-modified silicone (A) is less than 10% by weight, slipperiness and anti-blocking properties are insufficient, so that the sticking position is displaced and the film is easily wrapped when the envelope window is stuck. Also, 8
If it exceeds 5% by weight, the adhesion to paper is deteriorated, which is not preferable. By setting the polyoxyethylene alkylamine (B) to 15% by weight or more, it is possible to impart good antistatic performance especially under low humidity conditions (20 ° C., relative humidity 20%). If it is less than weight%,
Since the antistatic property is insufficient, clogging of the film and displacement of the sticking position are likely to occur when the envelope window is stuck. Also,
If the content exceeds 90% by weight, the friction between the films and the anti-blocking property are deteriorated, and the film is liable to be wound around the envelope window. Further, it is difficult to stably feed a roll-shaped film, which is not preferable. It was difficult to satisfy all of the antistatic properties, slip properties, and anti-blocking properties by using these single coating systems of the polyether-modified silicone (A) and the polyoxyethylene alkylamine (B). In combination, the uniform dispersibility of the polyether-modified silicone on the film surface is improved, the slip property and the antistatic property are synergistically improved, and the anti-blocking property can be simultaneously provided. In addition, from the viewpoint of the above balance of performance, the polyether-modified silicone (A) may be used in an amount of 40.
It is preferable to mix and apply 60 to 40% by weight of polyoxyethylene alkylamine (C) to 60% by weight.

In the coating composition of the present invention, a water-soluble polymer such as polyvinyl alcohol, polyvinylpyrrolidone, or sodium polyacrylate is added to the coating composition in order to prevent the applied composition from transferring from the film surface to the outside. You may add in the range which does not impair the requirement and characteristic of invention. The amount of the coating composition applied to the polylactic acid-based resin film in the present invention is at least 2 to 3 on one side.
0 mg / m ² , preferably ² to 15 mg / m ² . Is less than 2 mg / m ^2, the deviation of the attaching position at the time of bonding the envelope window for antistatic property is insufficient is likely to occur, in opposition to 30 mg / m ² or more, since the anti-blocking property is deteriorated, preferably Is difficult to use.

As a method of forming a coating film on the polylactic acid resin film of the coating composition, a conventionally known method such as a spray coater, a roll coater, a squeeze roll coater, and an air knife coater can be employed. In order to apply uniformly on the film surface, and in the above application amount range, dilute the coating composition with a solvent such as water or an organic solvent, and apply it uniformly on the polylactic acid resin film surface with the above coater. After that, a method of drying and removing the solvent in a drying furnace such as a hot air dryer is preferable.

In the polylactic acid resin film of the present invention, when the coating film is formed on both surfaces, a method of applying a coating composition on both surfaces is preferable.
After applying the coating composition diluted with the solvent on one side and before drying completely (before the solvent is completely removed)
It is also possible to adopt a method in which the film is wound into a roll, the coating composition is transferred to the opposite surface by winding tension, and a coating film is formed on both surfaces.

[0033]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described by way of examples and comparative examples. First, evaluation methods used in Examples and Comparative Examples will be described below. (1) Half-time of decay of charged voltage Static honest meter (H-made by Shishido Electrostatic Co., Ltd.)
0110 type) in accordance with JIS-L-1094 in an atmosphere of a temperature of 20 ° C. and a relative humidity of 20% under the conditions of an applied voltage of 10 kv and an electrode-sample distance of 20 mm. Significant figures were obtained up to the first digit.

(2) Coefficient of kinetic friction between film and metal According to JIS-K-7125, a stainless steel sliding piece having a contact area with the film of 50 mm × 30 mm, a weight of 110 g and a mirror-finished surface is used, and The dynamic friction coefficient was measured at a rate of / min. Under environmental conditions of a temperature of 23 ° C. and a relative humidity of 50%, and the number of decimal places up to the second decimal place was obtained as a significant figure.

(3) Coefficient of static friction between films In accordance with ASTM F254-89, a sample film was stuck on a table capable of changing the inclination angle, and then the same film as the sample was stuck on the surface, weighing 200 g.
Are placed so that the film surfaces are in contact with each other. Then, the inclination angle of the table is tilted from 0 ° (horizontal) to 90 ° (vertical) at a rate of 90 ° / min, and the inclination angle θ of the table when the metal piece to which the film is attached starts to slide is determined. Reading was performed to one digit after the decimal. From the angle θ, the coefficient of static friction was calculated by the following formula, and the number was calculated as a significant figure up to the second decimal place. The measurement is
The test was performed under environmental conditions of a temperature of 23 ° C. and a relative humidity of 50%. Static friction coefficient = tan θ

(4) Anti-blocking properties Sample films cut to a width of 70 mm are overlapped.
Under a load of 50 kg / cm2, temperature 50 ° C, relative humidity 85
After holding for 15 hours under the% condition, the load at the time of peeling the contact surface was measured, and the anti-blocking property was evaluated according to the following criteria. ：: Load at peeling ≦ 10 g (good blocking prevention) ○: 10 g <load at peeling ≦ 15 g (slightly good blocking prevention) Δ: 15 g <load at peeling ≦ 30 g (slightly poor blocking prevention) ×: Peeling load> 30 g (poor blocking prevention)

(5) Evaluation by Envelope Window Pasting Machine Using a window pasting machine (WINKLER + DUNNERBIER type HELIOS 202), 1000 was placed on a 50 × 90 mm window frame in a 135 × 235 mm envelope (made of paper).
At the speed of sheets / min, 20,000 envelopes were pasted on a window, and the following items were evaluated.

(5-a) Evaluation of misregistration Out of 20,000 window-attached envelopes, 19001 sheets to 2 sheets
10 out of 1000 sheets up to the 0000th sheet at random
0 samples were extracted, and one sample having a deviation from a predetermined bonding position of less than 0.5 mm was selected as one point, from 0.5 mm to 1.0 mm.
0.5 mm for items less than 1.0 mm, and 0 for 1.0 mm or more
The points were evaluated based on the total score of 100 sheets. ◎: 100 points ：: 97.5 to 99.5 points Δ: 95.
0-97.0 points ×: less than 95.0

(5-b) Evaluation of Winding Between Films The following criteria were used to evaluate the number of times winding occurred between films during the application of 20,000 windows. ◎: 0 times ○: 1 time △: 2 times ×: 3 times or more

(6) Weight average molecular weight Using gel permeation chromatography (GPC) manufactured by Waters, using chloroform as a solvent, the concentration of a chloroform solution of a sample to 1 mg / 1 cc, a solvent temperature of 40 ° C., and a solvent flow rate The measurement was performed at 1 ml / min. The weight average molecular weight was determined by conversion into polystyrene using standard polystyrene.

(7) Glass Transition Temperature and Melting Point Using a differential scanning calorimeter (DSC) manufactured by Perkin-Elmer, Model DSC-7, about 10 mg of a sample was dissolved at a rate of 10 ° C./min. ℃ to 200
The temperature was raised to ° C., and the glass transition temperature and the melting point were measured.

(8) Biodegradability test The test film was cut into a size of 100 mm in length and 100 mm in width, sandwiched between stainless steel net-like sample holders of 1 mm mesh, and buried at a depth of about 10 cm in the ground. The weight of the film remaining after a lapse of months was measured. Those with a residual ratio of 40% or less were evaluated as ○, those with a residual ratio of 40 to 90% as Δ, and those with a residual ratio of 90% or more as X.

The polylactic acid-based resin in the following Examples and Comparative Examples was prepared by directly condensing polylactic acid with 90% L-lactic acid using tin powder as a catalyst according to the method described in JP-A-6-65360. A coalescence was obtained. The weight average molecular weight of the obtained polylactic acid was 180000, the glass transition temperature was 57 ° C, and the melting point was 150 ° C. In the following Examples and Comparative Examples, all the tests were performed using this polylactic acid-based resin. However, the composition of the polylactic acid-based resin in the present invention is not limited to this.

In addition, in forming a film into a stretched film, the resin is extruded from a T-die using a single screw extruder, quenched by a casting roll, and then tripled in the MD direction.
Roll stretching and then TD at a stretching temperature of 60 ° C with a tenter
The film was stretched three times in the direction and subsequently heat-treated at 110 ° C. in a tenter to obtain a 30 μm-thick stretched film of a polylactic acid-based resin. In the films of the present example and the comparative example, the upper surface in the tenter is referred to as an upper surface, and the lower surface is referred to as a lower surface. As in the case of the resin composition, the above-mentioned film was used in all the examples and comparative examples.

In Examples and Comparative Examples, Table 1 and Table 2 show surfactants such as polyether-modified silicone and polyoxyethylene alkylamine, which were blended as coating compositions. As a method of applying the surface treating agent in Examples and Comparative Examples, first, a corona treatment was performed so that the surface of the film to be applied had a surface tension of 500 μN / cm. The corona treatment was performed using AGI-060MD manufactured by Kasuga Electric Co., Ltd. Next, an aqueous solution of the coating composition having a surface treatment agent concentration of 0.3% by weight was applied to the film surface with a spray coater, and then passed through a hot air dryer at 90 ° C. to remove moisture. The coating amount was adjusted under the conditions of the spray coater (air pressure and line speed), but the coating amount described in Examples and Comparative Examples was 10 m for the film after coating.
Sample No. ² was sampled, the coating composition was washed with ethyl alcohol, the film weight after washing was weighed, and the difference in weight before and after washing was calculated in mg / m ² .

[0046]

Examples 1 to 5 The films of Examples 1 to 5 shown in Table 3 were prepared by blending the polyether-modified silicone of Table 1 and the polyoxyethylene alkylamine of Table 2 as a coating composition, and applying the composition to the film. However, it is within the range of the composition and coating amount which are the requirements of the present invention. As shown in the evaluation results in Table 3, antistatic properties (half-life of charged voltage), slip properties (film-metal dynamic friction coefficient, film-film static friction coefficient), and
It has excellent anti-blocking properties, and extremely excellent evaluation results have been obtained with an envelope window sticking machine.

[0047]

Comparative Examples 1 to 6 Comparative Examples 1 to 6 are shown in Table 3 with respect to the above examples. Comparative Examples 1 to 6 are cases in which polyether-modified silicone and polyoxyethylene alkylamine were individually applied to a film, which deviated from the requirements of the present application. As shown in the evaluation results in Table 3, when these coating agents are added alone, even if the coating amount is increased or decreased,
Since the antistatic property, the antiblocking property, and the slipperiness cannot be balanced, and a position shift occurs when the envelope window is applied, it is preferably difficult to use.

In the case where the polyether-modified silicones of Comparative Examples 1 to 3 were applied alone, the antistatic properties were insufficient when the amount of application was small, resulting in displacement during application of the envelope window. Conversely, when the amount of application was increased, the adhesiveness to paper also deteriorated, so that misalignment was likely to occur when the envelope window was applied.
When the polyoxyethylene alkylamines of Comparative Examples 4 to 6 were applied alone, the antistatic properties were insufficient and the slipperiness was poor when the coating amount was small, so that misregistration was likely to occur when attaching the envelope window. Conversely, when the coating amount was increased, the anti-blocking property was deteriorated, and the winding of the film at the time of applying the envelope window was likely to occur.

Regarding biodegradability, Examples 1 to 5 and Comparative Examples 1 to 6 were all ○, showing good biodegradability.

[0050]

Examples 6 to 10 In Examples 6 to 10 shown in Table 4, the coating amount of the coating composition was larger than that in Examples 1 to 5. Yes, the evaluation results also satisfy the object of the present invention.

[0051]

Comparative Examples 7 and 8 In Comparative Examples 7 and 8 in Table 4, the amount of coating on the film was the same as in Examples 6 to 10, but the mixing ratio of the coating composition was outside the requirements of the present invention. It is. These films are in the range deviating from the requirements of the present invention, the antistatic property, the anti-blocking property, and the balance of the slipperiness is not balanced, the position shift at the time of applying the envelope window, or film winding occurs, Preferably, it is difficult to use.

Comparative Example 7 is a case where the ratio of the polyether-modified silicone is high and the ratio of the polyoxyethylene alkylamine is low. As shown in the evaluation results in Table 4,
Since the antistatic property was insufficient, the misregistration at the time of applying the envelope window was increased, and the result was △. Comparative Example 8 is a case where the ratio of the polyether-modified silicone is low and the ratio of the polyoxyethylene alkylamine is high. In this case, the anti-blocking property was poor, and the film winding when attaching the envelope window was poor.

[0053]

Comparative Examples 9 and 10 Comparative examples 9 and 10 in Table 4 are cases where only the type of polyoxyethylene alkylamine was changed from Comparative Examples 7 and 8, respectively. Similar to Comparative Examples 7 and 8, the compounding ratio deviates from the requirements of the present invention, and the misalignment when attaching the envelope window increases, so that it is difficult to use it preferably. Comparative Example 9 is a case where the ratio of the polyether-modified silicone is high and the ratio of the polyoxyethylene alkylamine is low. As shown in the evaluation results in Table 4, since the antistatic property was insufficient, the misregistration at the time of applying the envelope window was increased, and the evaluation was Δ.

In Comparative Example 10, the ratio of the polyether-modified silicone was low and the ratio of the polyoxyethylene alkylamine was high. In this case, the anti-blocking property was poor, and the film winding when attaching the envelope window was poor.

[0055]

Comparative Examples 11 and 12 In Comparative Example 11 in Table 4, the blending ratio of the polyether-modified silicone and the surfactant and the coating amount on the film were the same as in Example 6, and Comparative Example 12 was the same.
Was the same as that of Example 7, except that a surfactant other than the requirements of the present invention was used. In any case, a product that achieves the object of the present invention was not obtained.
Comparative Example 11 is a case where hydroxyethyl laurylamine was used as a surfactant. In Comparative Example 11 in which the proportion of the surfactant was small, the antistatic property was low, and the positional shift when attaching an envelope window was Δ, The anti-blocking property was also poor.

Comparative Example 12 is a case where coconut oil fatty acid amide was used as a surfactant. In Comparative Example 12 in which the proportion of the surfactant was large, the antistatic property was not sufficient, the positional shift when attaching the envelope window was Δ, the film winding was also Δ, and the anti-blocking property was Δ.

[0057]

Comparative Examples 13 and 14 In Comparative Examples 13 and 14 in Table 4, polyether-modified silicone and polyoxyethylene alkylamine were blended as a coating composition, but the amount applied was outside the requirements of the present invention. is there. When the coating amount is small, the antistatic property is insufficient, and the positional deviation at the time of applying the envelope window is likely to occur. Conversely, when the coating amount is large, the blocking prevention property is deteriorated. In any case, it is preferably difficult to use.

In Comparative Example 13, where the amount of coating was too small, the antistatic property and the slipperiness were poor, and the positional deviation when attaching the envelope window was x. Comparative Example 14 is the case where the coating amount is too large, but the antistatic property is high, but the antiblocking property is △, and the adhesiveness with paper is deteriorated. Became x. Examples 6 to 10 and Comparative Examples 7-1 for biodegradability
4. All were good, showing good biodegradability.

[0059]

[Table 1]

[0060]

[Table 2]

[0061]

[Table 3]

[0062]

[Table 4]

[0063]

The polylactic acid-based resin film of the present invention is characterized by using a specific polyether-modified silicone and a specific polyoxyethylene alkylamine in combination while having biodegradability in a natural environment. It is possible to balance the excellent antistatic effect (half-time of the charged voltage of 60 seconds or less under the conditions of 20 ° C. and 20% relative humidity), which was not realized, and the anti-blocking property and the slipperiness. As a result, a high speed running of the film can be achieved.
In high-speed window sticking to an envelope exceeding 00 sheets / minute, the present invention provides a good finish and machine suitability in which the sticking position is not shifted and the film is not wound.

Continued on front page F-term (reference) 4F006 AA35 AB35 AB39 BA07 CA07 DA04 4F100 AJ02B AJ02H AJ03B AJ03H AK41A AK52B AK52C AK52K AK54B AK54C AK54K AL05B AL05C BA02 J03 BA06 BA10C00 J15 BA10B BA00BJC JCC YY00C

Claims (3)

[Claims] 1. A film mainly comprising a polylactic acid resin, wherein (A) a polyether-modified silicone: 85
A coating composition consisting of 10 to 10% by weight and (B) a polyoxyethylene alkylamine having the structure of the following formula (1): 15 to 90% by weight is coated on at least one surface of the film at a rate of ^{2 to} 30 mg / m ² . A polylactic acid-based resin film, which forms a film. Embedded image (Wherein, R is an alkyl group having 8 to 22 carbon atoms, x = 1 to 3)
Integer of 0 and y = 1 to 30. ) 2. The polyether-modified silicone (A)
The polylactic acid-based resin film according to claim 1, which has a structure represented by the following formula (2). Embedded image (Wherein, R is H or a lower alkyl group having 1 to 4 carbon atoms, m is an integer of 0 to 80, n is an integer of 1 to 30, m + n
= An integer of 1 to 100, n / (n + m) = 0.1 to 1, a
= Integer of 5 to 30, b = integer of 0 to 30, a + b = 5
The integer of 60 and the ratio of a: b are 100: 0 to 50:50. ) 3. At least one surface of the film has a coefficient of dynamic friction between the film and the metal of 0.15 to 0.30, a coefficient of static friction between the films of 0.35 to 0.45, and
The polylactic acid-based resin film according to claim 1 or 2, wherein the half-life of the charged voltage decay at 0 ° C and a relative humidity of 20% is 60 seconds or less.