JP2860140B2 - Thermoplastic resin film with improved lubrication and anti-blocking properties - Google Patents

Description

The present invention relates to a thermoplastic resin film having improved lubricity and anti-blocking property.

Films made from resin compositions containing various thermoplastic resins as the main components, such as polyolefin, polyester, polyvinyl chloride, polyamide, and polystyrene, are used for packaging materials, photographs, magnetic recording media, capacitors, etc. Are widely used as industrial base films, but in recent years, with the diversification of these base films and the advancement of their functions, demands for improving the surface properties of the base films have been increasing. For example, in the field of magnetic recording media in which a base film formed from a resin composition containing a linear aromatic polyester as a main component is used, the recording density, capacity, and reliability have been increasing with the increase in recording density. In addition, there is a strong demand for providing the base film with better lubricity as the base film becomes thinner. Also, in the field of packaging materials in which a base film formed from a resin composition containing polyolefin as a main component is used, kneading is performed to impart antistatic properties, printability, anti-fog properties, and the like to the base film. The surfactant or hydrophilic polymer compound to be incorporated or applied promotes the blocking property between the film surfaces, and therefore, there is a strong demand for imparting an anti-blocking property to the base film.

The present invention relates to a new thermoplastic resin film that meets the above-mentioned requirements by containing specific spherical composite fine particles.

<Prior art and its problems> Conventionally, as means for imparting lubricity or anti-blocking property to a thermoplastic resin film, 1) a catalyst used in the synthesis of a polymer which is a main component of the thermoplastic resin film, etc. 2) means for adding inert particles such as calcium carbonate and clay (JP-A-52-3645, JP-B-59-8216), 3) silica, titania, organic poly Means for adding spherical fine particles such as siloxane (JP-A-59-171623, JP-A-62-172031,
JP-A-62-207356 and JP-A-63-178144) have been proposed.

However, the conventional means of 1) has a problem that it is difficult to control the deposited fine particles because the shapes, sizes, amounts, etc. thereof are not uniform. In the conventional method 2), it is difficult to completely inactivate the surface of the particles, and therefore, there is a problem that a part of the particles react with the polymer to cause coloring. As a result of generating coarse particles between each other, clogging of the filter in the film forming process, tearing of the film, fish eyes and the like are likely to occur,
Further, there is a problem that when a formed base film is used as a magnetic tape, dropout or the like is apt to occur.
The conventional means of 3) has a problem that spherical fine particles are likely to aggregate to form coarse particles. Therefore, in actual addition, it is necessary to disintegrate the aggregated spherical fine particles. Since many spherical fine particles are broken by mechanical external force at the time of crushing, there is a problem that as a result, many irregular shaped particles are added.

After all, any conventional means does not adversely affect the intrinsic properties of the thermoplastic resin film, which is the base film, and has good lubricity and anti-blocking properties as recently required for the thermoplastic resin film. It is not possible to give the property.

<Problems to be Solved by the Invention, Means for Solving the Problems> The present invention is to solve the above-mentioned conventional problems and to provide a new thermoplastic resin film which meets the above-mentioned requirements.

Thus, the present inventors have conducted intensive studies in view of the above, and as a result, they have been formed from a specific polysiloxane and a specific vinyl polymer in which both are integrally mixed and both are not substantially covalently bonded. The present inventors have found that a thermoplastic resin film containing a predetermined amount of the specific spherical composite fine particles thus obtained is correct and suitable, and have completed the present invention.

That is, the present invention, the following spherical composite fine particles 0.005 ~
The present invention relates to a thermoplastic resin film having improved lubricity and anti-blocking property, characterized by comprising 5% by weight.

Spherical composite fine particles: spherical composite fine particles formed of a polysiloxane of the following (I) and a vinyl polymer of the following (II) in which both are integrally mixed and both are not substantially covalently bonded. And the polysiloxane / vinyl polymer is 97/3 to 30/70 (weight ratio), the average particle size is 0.05 to 5 μm, and the standard deviation of the particle size distribution is 1.0 to 2.
5, and spherical composite fine particles having a ratio of major axis to minor axis of 1.0 to 1.2.

(I); the general formula _{[R n SiO (4-n} ) / 2] in a one or polysiloxane composed of two or more of the structural units represented, and n is at least 15 mole one following structural unit % Polysiloxane.

[However, n is an integer of 0-3. R is an unsubstituted or substituted hydrocarbon group having a carbon atom directly bonded to a silicon atom, and having no radical polymerizability. (II); a vinyl polymer obtained by polymerizing one or more vinyl monomers having no reactivity with a silanol group and a silanol group-forming atomic group.

The thermoplastic resin film of the present invention is a film formed from a resin composition containing a thermoplastic resin as a main component.
Specifically, a linear aromatic polyester film, a polyamide film, a polyolefin film obtained from a homopolymer of ethylene or propylene or a copolymer based on them, a polystyrene obtained from a homopolymer of styrene or a copolymer based on the same Examples of the film include a film, a polyvinyl chloride film obtained from a homopolymer of vinyl chloride or a copolymer mainly containing the same. Among them, linear aromatic polyester films, polyamide films, and polyolefin films are useful for the purpose.

The linear aromatic polyester film is not particularly limited as long as it can be obtained from a polyester that can be molded as a film.Specific examples of such polyester include polyethylene terephthalate, polybutylene terephthalate, polyethylene-p-oxybenzoate, In addition to homopolyesters such as poly-1,4-cyclohexylene dimethylene terephthalate and polyethylene 2,6-naphthalenedicarboxylate, there are copolymerized polyesters. And the copolymerization component at the time of synthesizing such a copolymerized polyester, diol components such as diethylene glycol, neopentyl glycol, polyalkylene glycol, adipic acid, sebacic acid, phthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, There are dicarboxylic acid components such as 5-sodium sulfoisophthalic acid, and polyfunctional carboxylic acid components such as trimellitic acid and pyromellitic acid. The polyamide film may be any polyamide as long as it can be obtained from a polyamide that can be molded as a film, and such polyamide is 6-nylon or a main component thereof. The density and molecular three-dimensional structure of the polyolefin film are not particularly limited, and any film obtained from a polyolefin that can be formed into a film may be used.

In the spherical composite fine particles used in the present invention, the average particle diameter is determined by arbitrarily selecting 50 particles from an electron micrograph, and selecting the long diameter of each selected particle (the longest diameter passing through the center of the particle =
D _L ) and the short diameter (the shortest diameter passing through the center of the particle = D _S ) is the average value of (D _L + D _S ) / 2 calculated, and the ratio of the long diameter to the short diameter is the same. _Is the average value of D _L / D _S calculated by measurement. The standard deviation value of the particle size distribution is a value obtained by particle size distribution measurement using an ultracentrifugal sedimentation system. The spherical composite fine particles have an average particle size of 0.05 to 5 μm, a standard deviation of the particle size distribution is in a range of 1.0 to 2.5, and a ratio of a major axis to a minor axis is in a range of 1.0 to 1.2, The ratio of major axis to minor axis is 1.
Although it is spherical because it is in the range of 0 to 1.2, among these, the average particle size is suitably 0.1 to 3 μm, and the standard deviation of the particle size distribution is in the range of 1.0 to 2.0, Further, those having a ratio of the major axis to the minor axis in the range of 1.0 to 1.1 are preferable.

The polysiloxane which is one of the components forming the spherical composite fine particles used in the present invention is a polysiloxane comprising one or more of the structural units represented by the general formula (I), and Is a polysiloxane containing at least 15 mol% or more of constituent units in which n is 1 or less. Specifically, it is a polysiloxane comprising one or more structural units represented by [SiO ₂ ], [RSiO _3/2 ], [R ₂ SiO] or [R ₃ SiO _1/2 ]. A polysiloxane containing at least 15 mol% or more, preferably 20 mol% or more of one or two of the structural units represented by [SiO ₂ ] or [RSiO _3/2 ], wherein n is 1 or less. is there. n
If the number of constituent units having a value of 1 or less is less than 15 mol%, spherical composite fine particles having the above-described characteristics relating to the particle size cannot be obtained.

In the structural unit of the polysiloxane as described above, R
Is an unsubstituted or substituted hydrocarbon group having a carbon atom directly bonded to a silicon atom, and among such hydrocarbon groups, a hydrocarbon group having no radical polymerizability. It is essential that R is a hydrocarbon group having no radical polymerizability, so that the polysiloxane and the vinyl polymer forming the spherical composite fine particles of the present invention are integrally mixed without substantially covalent bonding. Requirements.

When R is an unsubstituted hydrocarbon group, examples of R include an alkyl group, a cycloalkyl group, an aryl group, an alkylaryl group, an aralkyl group and the like. 1-4 alkyl or phenyl groups are advantageously chosen. Further, when R is a substituted hydrocarbon group, examples of R include a substituted hydrocarbon group having a halogen, an epoxy group, a cyano group, a ureido group and the like, among which a γ-glycidoxypropyl group, β -(3,4-epoxy) cyclohexylethyl, γ-chloropropyl, trifluoropropyl and the like are advantageously selected. These unsubstituted hydrocarbon groups and substituted hydrocarbon groups can be in any ratio.

The vinyl polymer, which is another component of the spherical composite fine particles used in the present invention, is a vinyl monomer having no reactivity with silanol groups and silanol group-forming atomic groups as described in (II) above. Is a vinyl polymer obtained by polymerizing one or more of the above. That the vinyl polymer is obtained by polymerizing a vinyl monomer having no reactivity with a silanol group and a silanol group-forming atomic group, the polysiloxane and the vinyl polymer forming spherical composite fine particles are This is an essential requirement for coexistence and coexistence without substantial covalent bonding.

As described above, as the vinyl polymer, polystyrene,
Aromatic vinyl polymers such as poly α-methyl styrene, polymethyl methacrylate, polybutyl methacrylate, polymethyl acrylate, polyvinyl acetate, aliphatic vinyl polymers such as polypropionate, polyacrylonitrile, styrene / α-methyl styrene Vinyl copolymers such as copolymers, styrene / acrylonitrile copolymers, styrene / methyl methacrylate copolymers, and crosslinked vinyls such as styrene / divinylbenzene copolymers, methyl methacrylate / trimethylolpropane trimethacrylate copolymers Copolymers and the like, among which,
An aromatic vinyl polymer obtained by polymerizing styrene, α-methylstyrene, or the like or an aliphatic vinyl polymer obtained by polymerizing an alkyl ester of methacrylic acid or acrylic acid is advantageously selected.

The vinyl polymer which forms the spherical composite fine particles together with the polysiloxane is preferably a vinyl polymer obtained by polymerizing a water-insoluble vinyl monomer, as described above, but is preferably a vinyl polymer obtained by polymerizing a water-insoluble vinyl monomer. It may be a vinyl copolymer obtained by copolymerizing with a vinyl monomer. In this case, the copolymerization ratio of the water-soluble vinyl monomer can be arbitrarily selected as long as the obtained vinyl copolymer does not dissolve in water or extremely swell, but is usually 10 mol% or less. Is preferred.

The spherical composite fine particles used in the present invention are formed from the polysiloxane of the above (I) and the vinyl polymer of the above (II) in which both are integrally mixed and both are not substantially covalently bonded. Wherein the polysiloxane / vinyl polymer is in the range of 97/3 to 30/70 (weight ratio). If the ratio of the polysiloxane is higher than this range, the resulting spherical composite fine particles are liable to be broken by mechanical impact, and the dispersibility in the polymer material is deteriorated. Conversely, when the ratio of the vinyl polymer is higher than this range, the low-energy characteristics due to the polysiloxane of the obtained spherical composite fine particles are reduced, and the spherical composite fine particles are formed of a thermoplastic resin, which is a main component of the thermoplastic resin film. Prior to incorporation into a resin, for example, in polyethylene terephthalate, when dispersed in ethylene glycol used in the polymerization step, the dispersibility and stability deteriorate.

Next, a method for producing the spherical composite fine particles used in the present invention will be described. The spherical composite fine particles have the following (III)
In an aqueous medium in which a silanol group-forming silicon compound of the formula (I) and a vinyl monomer of the following (IV) coexist, the silanol group-forming silicon compound undergoes polycondensation while hydrolyzing, and once the vinyl monomer is It can be produced by producing spherical fine particles of polysiloxane mixed therein and then polymerizing the vinyl monomer in the presence of a radical polymerization catalyst.

(III): a silanol group-forming silicon compound represented by the general formula (V) or (VI), and a silanol group-forming silicon compound represented by R ¹ —SiX ₃ and / or
Or a silanol group-forming silicon compound containing at least 15 mol% or more of a silanol group-forming silicon compound represented by SiX ₄ in terms of silicon of all silanol group-forming silicon compounds.

General formula (V); R ¹ _p -SiX _4-p General formula (VI); [However, p is an integer of 0-3. q is an integer of 3-20. R ¹ , R ² ,
R ³ is an unsubstituted or substituted hydrocarbon group having a carbon atom directly bonded to a silicon atom, and has no radical polymerizability. X is an alkoxy group having 1 to 4 carbon atoms;
An alkoxyethoxy group having an alkoxy group having 1 to 4 carbon atoms, an acyloxy group having 2 to 4 carbon atoms, an N, N-dialkylamino group having an alkyl group having 1 to 4 carbon atoms, a hydroxyl group, a halogen atom or a hydrogen atom. (IV): One or more vinyl monomers having no reactivity with a silanol group and a silanol group-forming atomic group.

The silanol group-forming silicon compound of the above (III),
A raw material of polysiloxane, which is one of the components forming the spherical composite fine particles, is a silanol group-forming silicon compound represented by the general formula (V) or (VI), and R ¹ -Si
Containing at least 15 mol% or more silanol-forming silicon compound and thus represented by X ₃ and / or SiX silanol group forming silicide comprising it as indicated by the ₄ of silicon in terms of all silanol group forming silicides It is a silanol group-forming silicon compound. The vinyl monomer (IV) is a raw material of a vinyl polymer, which is another component of the spherical composite fine particles of the present invention, and has a reactivity with a silanol group and a silanol group-forming atomic group. Is one or more of vinyl monomers having no.

As described above, the method for producing the spherical composite fine particles includes:
It is roughly divided into a first stage for producing a polysiloxane and a second stage for producing a vinyl polymer. In the first stage, polycondensation is carried out in the presence of a vinyl monomer, which is a raw material of a vinyl polymer, while hydrolyzing a silanol group-forming silicon compound, which is a raw material of polysiloxane, in an aqueous medium. The catalyst used for condensation polymerization while hydrolyzing the silanol group-forming silicon compound may be a conventionally known catalyst. The polycondensation reaction while hydrolyzing is carried out by charging a silanol group-forming silicon compound and a vinyl monomer into an aqueous medium in which a catalyst is dissolved and stirring the mixture. The method of charging is not particularly limited. The temperature and time for polycondensation while hydrolyzing vary depending on the type and concentration of the raw materials, the type of solvent, the type and concentration of the catalyst, and the like, but the temperature is usually 0 to 90 ° C, preferably 0 to 60 ° C. And the time is usually in the range of 30 minutes to 24 hours. Thus, the first-stage reaction is carried out to produce polysiloxane, and spherical fine particles of the polysiloxane mixed with a vinyl monomer are obtained. Then, in the second stage, a vinyl monomer mixed in the polysiloxane spherical fine particles is polymerized in an aqueous medium in the presence of a radical polymerization catalyst. Various methods are possible for the transition from the first stage to the second stage. For example, if the catalyst used in the first stage has no problem in the reaction in the second stage, the process can be directly shifted to the second stage. it can.
A conventionally known radical polymerization catalyst may be used when polymerizing the vinyl monomer. The reaction for polymerizing the vinyl monomer is carried out by introducing a radical polymerization catalyst into an aqueous medium in which spherical fine particles of polysiloxane containing the vinyl monomer are dispersed under an inert gas atmosphere and stirring the mixture.
The temperature at this time varies depending on various conditions as in the case of the first stage, but is usually in the range of room temperature to the boiling point of the vinyl monomer, preferably 50 to 80 ° C. The second step reaction is thus carried out to produce a vinyl polymer, the desired one comprising a polysiloxane and a vinyl polymer, both of which are co-mingled and both are not substantially covalently bonded. To obtain spherical composite fine particles.

The average particle diameter of the resulting spherical composite fine particles, the standard deviation value of the particle diameter distribution and the ratio of the major axis to the minor axis are determined by the type and concentration of the raw materials used, the type of solvent, the type and concentration of the catalyst, and further the reaction temperature and reaction. It depends on time and the like, and can be adjusted by appropriately selecting these conditions. It can also be adjusted by the presence of an emulsifier, a dispersant, or the like in the reaction system, and further can be adjusted by crushing, dispersing, or classifying the obtained spherical composite fine particles by a dry or wet method.

The thermoplastic resin film of the present invention contains the above-mentioned spherical composite fine particles in an amount of 0.005 to 5% by weight. When the characteristic value relating to the particle diameter of the spherical composite fine particles deviates from the above-described range, or when the content of the spherical composite fine particles deviates from the above range, the intended effect of improving the slipperiness and anti-blocking property cannot be obtained or is obtained. The thermoplastic resin film itself or the thermoplastic resin film has an adverse effect when used for various applications. For example, when a thermoplastic resin film having the above-mentioned characteristic values or contents deviating from a predetermined range is used in the field of a magnetic recording medium, it affects the thickness of a magnetic layer applied to the thermoplastic resin film and affects the thickness. It degrades the electrical properties. In this sense, regarding the characteristic value related to the particle size of the spherical composite fine particles, the average particle size is 0.1 to 3 μm, and the standard deviation value of the particle size distribution is
1.0 to 2.0, the ratio of the major axis to the minor axis is preferably 1.0 to 1.1, and the content of the spherical composite fine particles is about 0.1.
It is preferably from 0.05 to 3% by weight, more preferably from 0.1 to 1% by weight.

In order to make the thermoplastic resin film contain the spherical composite fine particles, the polymer before film formation, which is the main component of the thermoplastic resin film, contains the spherical composite fine particles. The means for containing is not particularly limited. The spherical composite fine particles may be mixed and dispersed so as to have a predetermined concentration in the polymer in the molten state, or the spherical composite fine particles may be added and kneaded so as to have a concentration higher than the predetermined concentration in the polymer in the molten state. The polymer may be diluted during film formation, or may be added and dispersed in a polymer having a low melt viscosity at the stage of low melt viscosity, followed by polymerization. In the case of producing a linear aromatic polyester film or a polyamide film, it is effective to add and disperse spherical composite fine particles during the polymerization of those polymers, especially when producing a linear aromatic polyester film. It is preferable to disperse the spherical composite fine particles in advance in an alkylene glycol such as ethylene glycol or 1,4-butanediol, and then to add and disperse them in a polymer polymerization system. More preferably, the secondary aggregated particles are crushed in alkylene glycol to form primary particles and then added to the polymer polymerization system.

The thermoplastic resin film of the present invention contains a predetermined amount of specific spherical composite fine particles, but other additives such as an ultraviolet absorber, an antioxidant, and an antistatic agent as long as the effects of the present invention are not impaired. Can also be contained.

The thermoplastic resin film of the present invention is produced from a resin composition containing a thermoplastic resin containing specific spherical composite fine particles as a main component, by a conventional method such as an inflation method, a casting method, a uniaxial stretching method, and a biaxial stretching method. You. The thermoplastic resin film may be laminated with another film, or may be coated with a coating agent, or may be subjected to a high degree of physical, chemical and / or electrical treatment, depending on various uses. It is used specifically.

Hereinafter, examples of the present invention will be described, but the present invention is not limited to the examples.

<Examples and the like> Test Category 1 (Production of spherical composite fine particles) Fine particles 1 which are spherical composite fine particles used in the present invention below.
And the contents and results thereof are shown in Table 1 together with the fine particles 2 to 8 produced in the same manner.

The contents and results in Table 1 were measured by the following methods.

1) Average particle diameter and ratio of major axis to minor axis The spherical composite fine particles and the like obtained in each example were photographed with a scanning electron microscope (SEM). The shortest diameter passing through the center of this from the photograph captured images selected arbitrarily fifty particles, (longest diameter = D _L passing through the center of the particle) Selection was longer diameter of the individual particles and the minor axis (particles = D _S ) was measured and calculated (D _L
The average value of + D _S ) / 2 was defined as the average particle size, and the average value of D _L / D _S was defined as the ratio of the major axis to the minor axis.

2) Standard deviation value of particle size distribution The spherical composite fine particles and the like obtained in each example are ultrasonically dispersed in water containing 1% by weight of a 10 mol adduct of nonylphenol ethylene oxide, and an ultracentrifugal automatic dispersion is performed using the dispersion. The average particle size and the particle size distribution were measured with a particle size distribution measuring device (CAPA-700 manufactured by Dig Seisakusho Co., Ltd.). The value obtained by dividing the sum of the standard deviation of the particle size distribution and the average particle size by the average particle size was defined as the standard deviation value of the particle size distribution.

3) Polysiloxane content (% by weight) After the spherical composite fine particles obtained in each example were heated and dried in a nitric acid / perchloric acid (5/2) mixture to decompose organic substances,
Molybdenum blue method (colorimetric method; Anal. Chem., 19, 873, 194)
Seeking SiO ₂ content of 7 years) was a value calculated from the composition ratio of the SiO ₂ content and the charged silicon compound and a polysiloxane content.

・ Production of fine particles 1 In a flask were charged 658 ml of water and 8.3 g of 28% aqueous ammonia, and at room temperature, while slowly stirring to keep the contents in a two-layer state, 6 g (0.029 mol) of ethyl orthosilicate; 23 g (0.078 mol) of siloxane,
A mixture of 71 g (0.52 mol) of trimethoxymethylsilane and 10 g (0.096 mol) of styrene was added dropwise over 1 hour.
Polycondensation occurred while hydrolyzing at the solution interface in the layer state.
As the reaction proceeded, the product gradually settled to the lower layer, and the lower layer became cloudy, but after about 2 hours, the two-layer state disappeared and became a homogeneous system. Subsequently, the mixture was stirred vigorously for 3 hours under the same conditions, and then white fine particles were separated by filtration. Next, the white fine particles are charged into another flask together with 1000 ml of water, and the content is heated to 70 ° C. under a nitrogen stream, and 100 ml of a 1% aqueous solution of potassium persulfate is added.
Was added dropwise over 1 hour. After aging for 3 hours under the same conditions to carry out radical polymerization, the content was cooled to room temperature, and white composite fine particles were separated by filtration. Then, the white composite fine particles are washed and dried to obtain spherical composite fine particles (fine particle 1).
61 g was obtained.

The obtained fine particles 1 had an average particle diameter of 1.1 μm, a ratio of the major axis to the minor axis of 1.02, a standard deviation of the particle diameter distribution of 1.42, and a polysiloxane content of 86.3% by weight.

Test Category 2 (Production of Dispersion) Dispersions 1 to 8 of spherical composite fine particles used in the present invention are described below.
And methods for producing dispersions A to D for comparison, and their contents and results are summarized in Table 2.

The results in Table 2 were evaluated by the following methods.

1) Shape Retention For each of the obtained dispersions, 50 fine particles were arbitrarily selected from the image taken by the electron microscope described above, and the presence or absence of breakage of each selected fine particle was observed. Was evaluated.

◎: 1 or less fine particles with breakage ○: 2 to 6 fine particles with breakage Δ: 7 to 24 fine particles with breakage ×: 25 or more fine particles with breakage 2) Aggregation Presence or absence of particles Observed each dispersion obtained with a 1000 times optical microscope, 20
The degree of aggregation of the fine particles present in the range of × 20 μm was evaluated according to the following criteria.

○: Aggregated particles are less than 1% of all particles △: Aggregated particles are 1% or more and less than 10% of all particles ×: Aggregated particles are 10% or more of all particles 3) Dispersion stability Each obtained dispersion is conical. Put in a glass container, leave it tightly closed at room temperature, observe the separation state of fine particles daily,
Evaluation was made according to the following criteria.

◎: No separation of fine particles was observed even after one month ○: Separation of fine particles was observed from 7 days to January △: Separation of fine particles was observed from 2 days to 6 days ×: Separation of fine particles was 1 Production of Dispersions 1 to 8 and A to D 40 g of the fine particles shown in Table 2 and ethylene glycol in such an amount that the fine particles had a predetermined concentration were weighed, and preliminarily dispersed with a homomixer. Batch type sand grinder using glass beads of 0.60-0.85mmφ (manufactured by Igarashi Kikai Co., Ltd.
Disperse 1 to 8 by treating for 5 hours with a vessel capacity of 400 cc)
And AD.

Test Category 3 Examples and comparative examples of the present invention are listed below, and their contents and results are summarized in Tables 3 and 4.

The results in Tables 3 and 4 were evaluated by the following methods.

1) Presence or Absence of Agglomerated Particles Each of the produced films was photographed by an electron microscope as described above, and the image was observed in a range of 70 × 50 μm and evaluated according to the following criteria.

○: no aggregated particles existed △: aggregated particles existed slightly ×: aggregated particles existed in 10% or more of all particles 2) Presence / absence of voids Observation of the image of 1) above shows voids around fine particles Was determined.

3) Slippery A 13 mm wide tape-shaped sample was prepared from each of the produced films, and this sample was brought into contact with a stainless steel rod fixing pin (7 mmφ) with an incoming load of 30 g, and was reciprocated 30 times at 2.5 m / min. Was. The coefficient of friction after 30 reciprocations was measured using a friction coefficient measuring device (TR type manufactured by Toyo Seiki Co., Ltd., load 200 g, speed 300 mm / min), and the surface condition of the sample after 30 reciprocations was visually observed. It was observed and evaluated as an index of wear resistance according to the following criteria.

Abrasion resistance A: No change such as whitening or scratches is observed. O: Slight whitening or scratches are observed. Δ: Clear whitening or scratches are observed. X: Remarkable whitening or scratches are observed. And Comparative Examples 1-4 Using 100 parts by weight of dimethyl terephthalate, 70 parts by weight of ethylene glycol, and 0.035 parts by weight of manganese acetate tetrahydrate, the temperature was raised to 230 ° C. according to a conventional method to carry out a transesterification reaction. Next, after adding 0.03 parts by weight of trimethyl phosphate, the dispersions shown in Table 3 were added so that the content of the spherical composite fine particles and the like became a predetermined amount with respect to the polymer, followed by stirring. After 0.03 parts by weight of antimony trioxide was added, the temperature was raised, and a polycondensation reaction was performed under a high temperature and a high vacuum according to a conventional method to obtain polyethylene terephthalate having an intrinsic viscosity of 0.61 dl / g. The polyethylene terephthalate obtained here was dried at 180 ° C., formed into a sheet with an extruder set at 290 ° C., and then 3.5 parts in the vertical direction at 90 ° C. and in the horizontal direction.
The film was stretched 4.0 times and heat-set at 210 ° C. to produce a film having a thickness of 15 μm.

Test Category 3 (Example of use of spherical composite fine particles) Examples 8 to 10 and Comparative Examples 5 to 6 200 parts by weight of ε-caprolactam, 6 parts by weight of water, and 0.0 part of acetic acid
29 parts by weight and the amount of the fine particles shown in Table 4 in which the content becomes a predetermined amount with respect to the polymer were charged into a polymerization vessel, sealed after being replaced with nitrogen gas, and kept at 260 ° C. 3.5K the pressure from the time the inner pressure became 3.5 Kg / cm ² and allowed to remove part of the water in the can
The reaction was performed for 3 hours while maintaining the g / cm ² . Then
The pressure was gradually released over 1 hour to normal pressure, and the polymerization was further advanced in a nitrogen gas stream for 3 hours to obtain a polyamide. The relative viscosity of the polyamide obtained here was 2.60.

The above polyamide was extracted from a T-die at 250 ° C. with an extruder having a diameter of 30 mm, and was solidified by cooling at 110 ° C. with a casting roll to produce a film having a thickness of 40 μm.

Examples 11 to 13 Three kinds of fine particles 1, 3 or 6, polyethylene resin (Yukaron LF-540B, manufactured by Mitsubishi Yuka Co., Ltd.) and antistatic agent (glycerin monostearate / N, N-bishydroxyethyllaurylamine (1/1 mixture) was kneaded with a 25 mmφ twin screw extruder to prepare three types of master batches containing 3% by weight of fine particles 1, 3 or 6 and 2% by weight of an antistatic agent.

Then, using a polyethylene resin (same as above) mixed with 10% by weight of each master batch, three types of polyethylene films having a thickness of 30 μm were produced with a 30 mmφ inflation film forming machine. The appearance of each of the produced films was good, and no blocking was observed on any of the wound film rolls even after being left in an atmosphere of 23 ° C. × 65% RH for 2 weeks.

On the other hand, the film prepared and prepared in the same manner as above except that no fine particles were used was free of foreign matter and had a good appearance, but remarkable blocking was observed after standing as described above.

<Effects of the Invention> As is clear, in the present invention described above, the surface properties of the thermoplastic resin film, that is, the lubricity and the anti-blocking property, are not affected without adversely affecting the intrinsic properties of the thermoplastic resin film. There is an effect that it can be improved.

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁶ Identification code FI C08L 101: 00 (56) References JP-A-63-297431 (JP, A) JP-A-62-172031 (JP, A) JP-A-1-92235 (JP, A) JP-A-1-204959 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C08L 1/00-101/14 C08J 5/18

Claims (4)

(57) [Claims] (1) 0.005 to 5% by weight of the following spherical composite fine particles:
A thermoplastic resin film having improved lubricity and anti-blocking property, characterized by comprising: Spherical composite fine particles: spherical composite fine particles formed of a polysiloxane of the following (I) and a vinyl polymer of the following (II) in which both are integrally mixed and both are not substantially covalently bonded. And the polysiloxane / vinyl polymer is 97/3 to 30/70 (weight ratio), and the average particle size is
0.05-5 μm, standard deviation of particle size distribution is 1.0-2.5,
And spherical composite fine particles having a ratio of the major axis to the minor axis of 1.0 to 1.2. (I); the general formula _{[R n SiO (4-n} ) / 2] in a one or polysiloxane composed of two or more of the structural units represented, and n is at least 15 mole one following structural unit % Polysiloxane. [However, n is an integer of 0-3. R is an unsubstituted or substituted hydrocarbon group having a carbon atom directly bonded to a silicon atom, and having no radical polymer. (II); a vinyl polymer obtained by polymerizing one or more vinyl monomers having no reactivity with a silanol group and a silanol group-forming atomic group. 2. The method according to claim 1, wherein the vinyl polymer forming the spherical composite fine particles is an aromatic vinyl polymer or an aliphatic vinyl polymer obtained by polymerizing an alkyl ester of methacrylic acid or acrylic acid. Thermoplastic film with improved anti-blocking properties. 3. The spherical composite fine particles have an average particle size of 0.1 to 3 μm.
The thermoplastic resin film according to claim 1 or 2, wherein m and the standard deviation of the particle diameter are 1.0 to 2.0, and the ratio of the major axis to the minor axis is 1.0 to 1.1. 4. The thermoplastic resin film according to claim 1, wherein the thermoplastic resin film is formed from a resin composition containing a linear aromatic polyester as a main component and has improved lubricity and antiblocking property.