JPH0474379B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a polyester composition that provides molded articles with excellent slip properties, surface smoothness, and abrasion resistance. More specifically, by using a glycol monodispersion of specific spherical silica fine particles as a raw material for polyester, a polyester composition with improved slipperiness, surface smoothness, and abrasion resistance is obtained by blending a specific amount of the fine particles. It is related to. (Prior art) Polyester has excellent physical and chemical properties, and therefore its molded polyester film can be used for magnetic tape, optical photography, vapor deposition, etc.
Polyester fibers are widely used for condensers, packaging, etc., and polyester fibers are widely used for clothing, ropes, and other industrial materials. However, despite its excellent performance, various undesirable troubles may occur during the molded product manufacturing process. This is thought to be due to the poor slipperiness of polyester molded products. Furthermore, when a polyester film is used as a magnetic tape by coating or vapor depositing a magnetic layer on its surface, particularly good sliding properties are required. This is because if the slipperiness of the film is poor, scratches, wrinkles, etc. will occur on the film surface during film manufacturing, magnetic layer coating or vapor deposition, or other film handling, resulting in drop-outs and problems with the quality of the magnetic tape. This is because Furthermore, since it is essential for magnetic tapes to have good tape running properties, good slipping properties are required. For this purpose, a method has conventionally been practiced in which fine particles are present in polyester and molded to form irregularities on the surface of the film to reduce the frictional resistance. On the other hand, in recent years, as polyester films have become thinner and magnetic recording has become more dense and more efficient, the seemingly contradictory properties of film slipperiness and flattening of the film surface have come to be required. . As a solution to these conflicting performance demands, a method of forming fine and uniform irregularities on the film surface can be considered. By the way, conventional methods for forming irregularities on the surface of a film include (1) a method in which part or all of the catalyst, color inhibitor, etc. used during polyester synthesis are precipitated during the reaction process to exist as fine particles; (2) during polyester synthesis. A method has been proposed in which inorganic fine particles are added externally at any stage of the process. However, since method (1) involves generating particles during the polyester synthesis reaction, it is difficult to control the particle amount and particle diameter, and there are problems such as the generation of coarse particles being difficult to avoid. On the other hand, the inorganic fine particles added in method (2) include silica, titanium oxide, silica-alumina compounds, silica-magnesia compounds, glass powder, barium sulfate, calcium carbonate, clay, mica, talc, calcium phosphate, and magnesium phosphate. Conventional industrially available materials such as
Films with a diameter of 0.001 to 10 μm are used depending on the purpose of the film.
-3645 Publication, etc.). However, these conventionally used inorganic fine particles originate from their manufacturing method,
The particle size distribution was wide, and most of the particles were irregular in shape or contained a mixture of aggregated particles.
In the case of silica fine particles, silica with an average primary particle diameter of 0.02 to 0.1 μm obtained by thermal decomposition of silicon halide,
Silica particles are crushed into aggregates of 1 to 5 μm using the sodium silicon wet method, and silica is made by melting and spheroidizing crushed natural silica, and both have irregular particle shapes, and even if they are close to spherical, the particle size distribution may vary. It was very spacious. In the above-mentioned conventional method, unevenness is formed on the film surface to improve slipperiness, but as a result of the particles being irregular, the unevenness lacks uniformity, and therefore there is a natural limit to the flattening of the surface. On the other hand, the silica particles in silica aquasol produced using an ion exchange method using an aqueous sodium silicate solution are spherical and have a sharp particle size distribution, but only particles with a particle size of about 0.1 μm or less have been obtained. First, it has not been possible to sufficiently meet the demands of various polyester compositions. Further, when the present inventors measured the amount of silanol groups on the silica fine particles having an average particle size of 0.15 μm obtained by the above manufacturing method, it was found to be 0.4 mmol per gram of the fine particles, and the true specific gravity was 2.15. As a method to solve the problems of the conventional external addition method of fine particles, the present inventors previously proposed a patent application filed in 1983-
In No. 48456, the particles produced by hydrolyzing an organic silicon compound in an alcoholic solution are silica fine particles that are spherical and have a sharp particle size distribution, and when these are added to polyester, they exhibit excellent slipperiness improvement. disclosed. However, silica generally has high hardness, and therefore polyester molded articles produced by adding silica fine particles often have problems in wear resistance. This problem becomes more pronounced as the particle size of the particles increases. For example, if a film formed by making silica particles larger than 0.1 μm exist in polyester is used as a base film for a magnetic tape, the base film may be scraped during the magnetic tape manufacturing process or during running. Even when the existing polyester was spun into fibers, there was a problem that the fibers were scraped when used by sliding them. On the other hand, fine silica particles, which are inorganic oxides, have poor affinity with polyester because they have silanol groups, which are hydrophilic groups, on their surfaces. For example, when a polyester film or fiber containing fine silica particles is stretched, voids are generated around the fine silica particles, resulting in a decrease in the transparency of the product and poor magnetic properties. (Problems to be Solved by the Invention) The present invention solves all the above-mentioned problems caused by the hardness of silica particles and the lack of affinity for polyester. Therefore, the object of the present invention is to provide novel slipperiness,
The object of the present invention is to provide a polyester composition that provides a molded article with excellent abrasion resistance and uniformity of surface irregularities. The present inventors have discovered that the above object can be achieved by using a glycol monodispersion of specific silica fine particles as a raw material for polyester and thereby containing the fine particles in a specific amount in the polyester, and have arrived at the present invention. did. (Means and effects for solving the problems) The present invention uses the glycol monodispersion of silica spherical fine particles described below added as a raw material for polyester, and the fine particles are added to the polyester from 0.005 to
The present invention relates to a polyester composition characterized in that it contains 2% by weight. Note: The average particle size is in the range of 0.1 to 5 μm, the standard deviation value of the particle size is in the range of 1.0 to 1.5, the amount of silanol groups in the fine particles is 1.0 mmol or more per 1 g of the fine particles, and the surface of the fine particles is coated with a coupling agent. A glycol monodispersion of amorphous spherical silica particles treated with In the glycol monodispersion of silica fine particles used in the present invention, the silica fine particles are amorphous spherical,
The average particle diameter is in the range of 0.1 to 5 μm, the standard deviation value of the particle diameter is in the range of 1.0 to 1.5, the particle size distribution is sharp, and the amount of silanol groups in the silica fine particles is 1.0 mmol or more per 1 g of the fine particles. , and the surface of the fine particles must be treated with a coupling agent, and the fine silica particles must be dispersed in the glycol without secondary aggregation. These numerical values are defined based on the analysis and evaluation methods described in the examples described later, but if they are outside the numerical range described above, the object of the present invention cannot be achieved. especially,
The amount of silanol groups in the silica fine particles is an important factor in controlling the hardness of the silica fine particles and obtaining a polyester molded article with excellent wear resistance. In addition, coupling agent treatment is important in maintaining good affinity with polyester despite the increase in silanol groups in the silica particles. Such a glycol monodispersion of spherical silica particles can be obtained by, for example, hydrolyzing a hydrolyzable organosilicon compound in an alcoholic solution to form a suspension of amorphous silica hydrate particles in an alcoholic solution. It is manufactured based on the method of obtaining. Silica hydrate fine particles are separated from the alcoholic solution suspension of silica hydrate fine particles by sedimentation or solvent evaporation, and then dried or calcined to obtain silica fine particles, which are then dispersed in glycol or A glycol monodispersion of silica spherical microparticles is produced by evaporating the alcoholic solvent in the suspension with glycol or optionally by subsequent heat treatment in glycol. At this time, in order to maintain the amount of silanol groups in the fine particles as described above, the thermal history of the fine particles is particularly important as will be described later. The treatment of the surface of the fine particles with a coupling agent can be carried out at any stage of the above-mentioned production process, for example, after producing a suspension of silica hydrate fine particles in an alcoholic solution, after separating the silica hydrate fine particles, or in glycol. A coupling agent can be added and processed at any stage during which the alcoholic solvent is evaporated or after the glycol monodispersion is formed. In the above-described method for producing a glycol monodispersion of silica spherical fine particles, the hydrolyzable organosilicon compound that is the raw material for the fine particles is a silicon compound containing a hydrolyzable organic group, which is hydrolyzed to form a hydrate. Any material that can be used may be used, and tetraalkyl silicate is preferably used as it is industrially easily available and inexpensive. Specific examples thereof include tetramethyl silicate, tetraethyl silicate, tetraisoproprisilicate, and tetrabutyl silicate. Further, other preferred organosilicon compounds include derivatives of tetraalkyl silicate,
For example, a tetraalkyl silicate in which some of the alkoxide groups are substituted with a group capable of forming a chelate compound such as a carboxyl group or a β-dicarbonyl group, or a tetraalkyl silicate or an alkoxide-substituted alkyl silicate compound partially hydrated. Low condensates obtained by decomposition are used. In addition to organic silicon compounds, titanium, zirconium, aluminum, sodium, potassium, rubidium, cesium, magnesium, calcium,
Strontium, barium, boron, gallium,
Hydrolysis is carried out in the coexistence of organometallic compounds or inorganic salts such as indium and tin, or after hydrolysis of an organosilicon compound to form silica hydrate fine particles, the above-mentioned metal compound is added and hydrolyzed, resulting in silica fine particles. It is also possible to deposit a metal hydroxide on the surface of the silica to finally form composite particles of silica and the metal oxide. In this case, the proportion of silica in the fine particles is preferably 70 mol% or more. The above-mentioned organosilicon compound is mixed with an alcoholic solution and hydrolyzed to obtain a suspension of silica hydrate fine particles in the alcoholic solution, and the mixing method can be any method such as all at once, divided, or continuous. At this time, it is preferable that the final concentration in the solution of the organosilicon compound be 2 mol/less or less, since aggregation of the produced silica hydrate fine particles is less likely to occur. As the alcohol in the alcoholic solution, alcohols such as methanol, ethanol, isopropanol, butanol, ethylene glycol, and propylene glycol are used alone or in combination. Water necessary for hydrolysis is allowed to coexist in the alcoholic solution. This water content affects the shape and diameter of the particles, so it needs to be controlled to a preferable amount, but it changes depending on the type of organosilicon compound, reaction conditions, etc. This water can also be supplied by moisture in the gas phase. Hydrolysis can be carried out, for example, by adding the above-mentioned organic silicon compound raw material or its alcoholic solution to the above-mentioned alcoholic solution and stirring at a temperature of 0 to 100°C, preferably 0 to 50°C for 10 minutes to 100 hours. It is done by folding. At this time, cations such as NH ₄ ⁺ and Na ⁺ are added as catalyst components in order to control the hydrolysis rate, but the amount varies depending on the raw material, and the effect on particle shape and particle size is taken into account. be selected as appropriate. By hydrolyzing the organosilicon compound in an alcoholic solution under appropriate conditions in this way, an alcoholic solution suspension in which silica hydrate fine particles are monodispersed can be obtained. Furthermore, the type and concentration of raw materials, reaction temperature, water concentration,
By appropriately selecting the type of alcohol, type and concentration of catalyst, reaction method, etc., silica hydrate fine particles can be spherical and have an average particle size controlled to any desired size within the range of 0.1 to 5 μm. Uniform particles with a standard deviation value in the range of 1 to 1.5, and more preferably in the range of 1 to 1.3, can be obtained by selecting preferable conditions. It has been found that the amount of hydroxyl groups contained in the silica hydrate fine particles obtained in this way is affected by the above-mentioned reaction conditions. In order to control the amount of silanol groups in the silica hydrate, it is also important to set the manufacturing conditions for the silica hydrate fine particles. The alcoholic solution suspension of silica hydrate fine particles produced in this way is finally solvent-substituted with glycol for the alcoholic solvent of the suspension, but at this time some of the hydrate fine particles are replaced with glycol. The desired glycol monodispersion of spherical silica particles is produced by dehydration. The alcoholic solvent refers to a solvent consisting of alcohol used when producing silica hydrate fine particles, water added in excess of the hydrolysis equivalent, volatile components in the catalyst, and organic substances produced as by-products from hydrolyzed organosilicon compounds. say. The glycol (B) used in the present invention is a starting material for polyester having 2 to 8 carbon atoms and 2 alkanol groups, such as ethylene glycol, 1,4-butanediol, neopentyl glycol, propylene glycol, diethylene glycol, or It is a glycol used as a copolymerization component. As a specific method for solvent replacement, for example, (1) hydrate fine particles in an alcoholic solution suspension of silica hydrate fine particles are separated by sedimentation, centrifugation, etc., and dried or optionally calcined powder is prepared. Method of monodispersing in glycol. (2) Any method can be used, such as distilling off the alcoholic solvent from a suspension of hydrate fine particles in an alcoholic solution in the presence of glycol to obtain a glycol monodisperse. Thereafter, the dispersion stability of the glycol monodispersion can be further increased by heat-treating the glycol monodispersion thus obtained at 70 to 300°C to intentionally bond glycol to the surface of the silica fine particles. . In this case, the amount of glycol bonded is preferably 0.003 mmol or more per 1 g of silica fine particles. The thermal history, that is, temperature, of silica fine particles until they are made into a glycol monodisperse is deeply related to the amount of silanol groups in the fine particles, and this relationship also depends on the manufacturing method of silica hydrate fine particles, the method of solvent replacement, etc. It became clear that there was a slight change in the Furthermore, in order to set the hardness of the silica fine particles in a preferable range and to make the final polyester molded product excellent in wear resistance, the amount of silanol groups in the fine particles should be 1.0 mmol or more, more preferably 2.0 mmol per 1 g of fine particles. I found out that it is best to control it within the above range. It was also found that the true specific gravity of the fine particles increases as the amount of silanol groups in the fine particles decreases, but the true specific gravity of all silica fine particles having silanol groups in the above range was 2.1 or less. The specific surface area (BET method) of the silica fine particles in the glycol monodisperse thus obtained is only about 5 times or less than the specific surface area calculated from the electron microscope observation diameter, and the Considering that the pore porosity is less than 20%, the amount of silanol groups in silica fine particles means that there are not only silanol groups present on the outer surface of the fine particles, but also a large amount of silanol groups blocked inside the particles. are doing. Incidentally, the silica fine particles defined in the present invention refer to fine particles in which a coupling agent (described later) or, in some cases, glycol is bonded to the surface or inside thereof, and 1 g of silica fine particles refers to the weight of the composite. It represents. Due to the hardness of the silica fine particles, some of the silanol groups present within a certain range also exist on the surface of the outer shell of the particles. When a glycol monodispersion of silica spherical fine particles is used as a raw material for polyester and the fine particles are present in the polyester, the problem arises that the affinity with the polyester is impaired due to the silanol groups on the surface of the outer shell of the fine particles. However, treatment with coupling agents is performed to improve the affinity. Coupling agents that can be used in the present invention are not particularly limited as long as they have one or more non-hydrolyzable organic groups and one or more hydrolyzable groups in the molecule, but those that are easily available can be used. Preferred examples include silane-based, titanate-based, and aluminum-based coupling agents. For example, methyltrimethoxysilane, phenyltrimethoxysilane, benzyltriethoxysilane, methyltriisopropoxysilane, 3-chloropropyltrimethoxysilane, dimethoxydimethylsilane, diethoxymethylphenylsilane, ethoxytrimethylsilane, 3-amino One or more types of ( Alkoxysilanes having (substituted) alkyl group, (substituted) phenyl group, vinyl group, etc., trimethylchlorosilane,
Chlorosilanes such as diethyldichlorosilane, acetoxysilanes such as acetoxytriethylsilane, diacetoxydiphenylsilane, and triacetoxyvinylsilane, silane coupling agents such as isopropyltriisostearoyl titanate, bis(dioctylpyrophosphate)oxyacetate titanate Examples include titanate coupling agents such as , aluminum coupling agents such as acetalkoxyaluminum diisopropylate, but are not limited thereto. The treatment with the coupling agent is as described above.
It may be carried out at any stage during or after the production of silica hydrate fine particles, after pulverization, during or after solvent replacement, or after making a glycol monodisperse of silica fine particles. The amount of the coupling agent added is in the range of 0.1 to 10% by weight, preferably 0.1 to 2% by weight, based on the weight of the silica fine particles converted to oxide. If it is below the lower limit, the effect will be small, and if it is above the upper limit, it will be effective but not economical. The temperature of coupling treatment ranges from 0 to 100℃,
Preferably, it can be carried out at room temperature. The glycol monodispersion of silica spherical fine particles used in the present invention is not limited to those obtained by the above-mentioned manufacturing method, and the fine particles are amorphous spherical, and the average particle diameter, standard deviation value of the particle diameter, The amount of silanol groups in the fine particles is within the above range, and the surface of the fine particles is treated with a coupling agent,
Any particles may be effective as long as a large amount of glycol is bonded to the surface of the fine particles. The polyester that can be applied in the present invention is:
It is a polyester whose main dicarboxylic acid component is terephthalic acid or its ester-forming derivative, and whose main glycol component is diglycol such as ethylene glycol, 1,4-butanediol, or its ester-forming derivative, but there are some differences in composition, manufacturing method, etc. The material is not limited, and may be blended with other polyesters. Glycol monodispersion of silica spherical fine particles can be added and used at any stage during the production of polyester, but from the beginning of the esterification or transesterification reaction between the dicarboxylic acid component and glycol until the end of the reaction and the formation of a prepolymer. Preferably, it is added at the initial stage of polycondensation of the prepolymer. The amount of the glycol monodispersion of silica spherical fine particles added is such that the silica fine particles are contained in the final polyester composition of the present invention in the range of 0.005 to 2% by weight. If the content of silica fine particles in the polyester composition is less than 0.005% by weight, the effect on the slipperiness of the molded product obtained by molding it is insufficient, and if it is more than 2% by weight, the film This is undesirable because it deteriorates physical properties such as breaking strength of polyester molded products such as fibers and fibers. As long as the content of the silica spherical fine particles disclosed in the present invention in the polyester composition is within the above range, coexistence with other fine particles is not hindered in any way. (Effect of the invention) A glycol monodispersion of silica fine particles having a specified shape, particle size, particle size distribution, and silanol group content and whose fine particle surface has been treated with a coupling agent is added and used as a raw material for polyester. As a result, the polyester composition of the present invention containing a specific amount of the fine particles can reliably and easily form homogeneous fine irregularities on the surface of polyester molded products such as films and fibers obtained by molding the composition. In addition, as the hardness of the silica fine particles is controlled, the wear resistance of polyester molded products can be improved, and the dispersion stability of the fine particles in polyester is good when a glycol monodisperse is added, and the affinity of the fine particles in polyester is improved. Molded products with excellent properties can also be obtained. Therefore, the polyester composition of the present invention has
Used in molded products such as films, sheets, and fibers, it exhibits excellent slipperiness, abrasion resistance, and uniformity of surface irregularities. In particular, the polyester film obtained from the composition of the present invention has excellent abrasion resistance, coatability of the magnetic layer when making a magnetic tape, and vapor deposition properties, and is useful for manufacturing magnetic tapes with excellent electromagnetic conversion properties. It is suitable. (Examples) Hereinafter, the present invention will be explained in more detail with reference to Examples, but the scope of the present invention is not limited by the Examples. In addition, the shape, average particle diameter, standard deviation value, presence or absence of aggregated particles, dispersion stability of the fine particles in the glycol dispersion sample of silica fine particles, and the crystallinity, silanol group content, and true Specific gravity, specific surface area, and amount of bound glycol were analyzed and evaluated by the following methods. ●Particle shape Determined by electron microscope observation at 50,000x magnification. ●Average particle diameter and standard deviation value: 100 arbitrary particles in an electron microscope image taken at 50,000 times magnification
The particle diameter of each particle was actually measured and calculated using the following formula. Standard deviation value = X + σ _o-1 /X However ●Presence or absence of aggregated particles The sample was observed and evaluated in the slurry state using an optical microscope at 1000x magnification. ●Dispersion stability Place the sample in a tightly closed glass container and let it stand.
The presence or absence of a particle sedimentation layer at the bottom of the container and a supernatant layer at the top was observed and evaluated based on the following criteria. 1
A sedimentary layer or a supernatant layer is observed after standing for a day.
× A sedimentary layer or a supernatant layer was observed between 2 days and 1 month. ○ A sedimentary layer or a supernatant layer was not observed even after 1 month. ◎ ● Crystallinity of fine particles A part of the dispersion Vacuum drying is performed at 50°C to completely remove volatile components such as glycol that are not bonded to the fine particles to obtain a powder sample of fine particles. The crystallinity of the fine particles of the powder sample was evaluated by X-ray diffraction analysis. ●Specific surface area The specific surface area of the powder sample obtained by the method described above was measured by the BET method. ●True specific gravity The true specific gravity of the powder sample obtained by the method described above was measured using a Shimadzu autopycnometer 1320. ●Amount of silanol groups in microparticles Potassium ferricyanide was added at various ratios as an internal standard to Aerosil 300, which had been quantified by replacing the amount of silanol groups with LiAlH ₄ in advance, mixed wet, and then vacuum-dried overnight. Form this into a disk with a thickness of about 0.1 mm,
Infrared absorption spectra were measured using FT-IR60SX manufactured by NICORET. 960cm ^-1 Si−
Absorption spectra attributed to OH and CN at 2120 cm ^-1 were observed, and a calibration curve was created from the peak area ratio of each absorbance, and a linear relationship was obtained. Next, a similar measurement was performed using the powder sample obtained by the method described above, and the amount of silanol groups in 1 g of fine particles was determined. ●Amount of bound glycol Accurately weigh approximately 1 g of the powder sample obtained by the method described above, add it to 50 ml of 0.05N NaOH aqueous solution, and continue stirring at room temperature for 10 hours. As a result, the glycol bound to the surface of the fine particles is completely hydrolyzed and extracted into an aqueous solution. The fine particles in the suspension were separated using an ultracentrifuge, and the amount of glycol in the clear liquid was determined using a gas chromatograph to quantify the amount of glycol bound to 1 g of fine particles. Production Example of Glycol Monodispersion of Silica Spherical Fine Particles 1 16 methanol and 1.5 kg of a 28% ammonium aqueous solution were added and mixed into a 30 glass reactor equipped with a stirrer, a dropping port, and a thermometer. 15% of the mixture
While adjusting the temperature to +/-0.5°C and stirring, a solution of 1.0 kg of tetramethyl silicate diluted in 2 parts of methanol was added dropwise from the dropping port over 1 hour.
Stirring was continued for a period of time to carry out hydrolysis to produce an alcoholic solution suspension of silica hydrate fine particles. At this time, the concentration of each raw material with respect to the total amount of the final solution was 0.32 mol/tetramethylsilicate and 2.90 mol/water.
, ammonia 1.19 mol/. Next, the silica hydrate fine particles in the suspension were separated by centrifugation and dried at 100° C. under normal pressure to obtain a powder of silica spherical fine particles. Next, the powder was added to ethylene glycol and monodispersed using ultrasonic waves, and then tetraoctyl bis(ditridecyl phosphite) titanate (KR-46B manufactured by Ajinomoto Co., Inc.) was added as a coupling agent to fine particles. On the other hand, 0.2% by weight (based on the weight calculated as SiO ₂ ) was added and subjected to coupling treatment to produce a glycol monodispersion of silica spherical fine particles (A) with a fine particle concentration of 10% by weight. Table 1 shows the evaluation results of the dispersion and the analysis results of the fine particles in the dispersion. Examples 2 to 3 The procedure was repeated in the same manner as in Example 1, except that instead of drying at 100°C after separating the silica hydrate fine particles, they were fired at 300°C or 600°C to form a powder. Ethylene glycol monodispersions of B) and (C) were produced. The results are shown in Table-1. Example 4 After producing an alcoholic solution suspension of silica hydrate fine particles in the same manner as in Example 1, methyltrimethoxysilane was added as a coupling agent to the suspension based on the silica equivalent amount of the silica hydrate fine particles.
A coupling treatment was performed by adding 0.8% by weight. On the other hand, there are 5 glass evaporation pots equipped with a stirrer, a dripping port, a thermometer, and a distilled gas outlet that can be heated by a heating medium from the outside, and the distilled gas outlet is followed by a distilled gas condenser, a vacuum suction port, and a condenser. Pour 1.2 kg of ethylene glycol into the evaporation pot of the evaporation device consisting of a liquid receiver.
While stirring, bring the system to normal pressure and raise the heating medium temperature to 150℃.
It was set to Next, 16.7 kg of the previously obtained suspension after the coupling treatment was continuously supplied from the dropping port while distilling out the alcoholic solvent containing methanol, water, ammonia, and ethylene glycol equivalent to the vapor pressure. Heating was continued even after the supply of the suspension was completed, and when the internal temperature reached 120° C., heating was stopped and the solvent was replaced to produce an ethylene glycol monodispersion of silica spherical fine particles (D). The results are shown in Table-1. Examples 5 to 7 The same procedure as Example 4 was carried out except that the type and amount of the coupling agent in Example 4 were changed as shown below. (coupling treatment with 0.5% by weight of 3-(2-aminoethylaminopropyl)-trimethoxysilane), and (G) (coupling treatment with 3% by weight of acetalkoxyaluminum diisopropylate)
Each ethylene glycol monodispersion (coupling treatment) was produced. The results are shown in Table-1. Example 8 An alcoholic solution suspension of silica hydrate fine particles was produced in the same manner as in Example 1, except that tetraethyl silicate was used instead of tetramethyl silicate and ethanol was used instead of methanol. The subsequent operations were carried out in the same manner as in Example 1 to produce an ethylene glycol monodispersion of silica spherical fine particles (H). The results are shown in Table-1. Example 9 In Example 1, tetrabutyl silicate was used instead of tetramethyl silicate, and n was replaced with methanol.
- After producing a suspension of silica hydrate fine particles in an alcoholic solution in the same manner except that butanol was used, the coupling treatment and solvent substitution were carried out in Example 4 using 1,4-butanediol instead of ethylene glycol. A monodispersion of silica spherical fine particles (I) in 1,4-butanediol was produced in the same manner except that the procedure was as follows. The results are shown in Table-1.

【table】

[Table] Example 1 0.04 parts by weight of manganese acetate tetrahydrate was added as a catalyst to 100 parts by weight of dimethyl terephthalate and 70 parts by weight of ethylene glycol, and the mixture was heated to 230°C to distill off methanol and perform a transesterification reaction. Summer. Then, the silica fine particles (A) produced in Example 1
After adding 3.0 parts by weight of ethylene glycol monodisperse and 0.03 parts by weight of antimony trioxide under stirring, the temperature was raised to 280°C below a final 1 Torr to perform polycondensation, and 0.3 parts by weight of silica fine particles (A) were added to the polyester.
A polyester composition (1) containing % by weight was obtained. This polyester composition (1) was extruded into a sheet form using an extruder set at 290°C, and then at 90°C.
After stretching 3.5 times in the longitudinal direction at 100°C, stretching 4 times in the horizontal direction at 100°C and heat treating at 210°C for 10 seconds to a thickness of 10 μm.
A biaxially stretched polyester film containing silica fine particles (A) was obtained. In addition, each glycol monodispersion of silica fine particles (B) and (D) to (I) obtained in Example 2 and Examples 4 to 9 is shown in Table 2.
Polyester compositions (2) to (8) containing the respective silica fine particles were obtained in the same manner as the above method except that the amounts added were used as shown in . Furthermore, using these compositions (2) to (8), respective polyester films were obtained in the same manner as above. When the surface of these films was observed using an electron microscope image taken at a magnification of 5,000 times, it was found that there were no aggregated particles, the particles were uniformly dispersed, and there were no voids around the particles, indicating good adhesion to the polyester. was good. On the other hand, regarding these films, ASTM-
When the static friction coefficients were measured using a slip tester according to the D-1894B method, all of the coefficients of static friction were 1.0 or less, indicating that they had excellent slip properties. Further, these films each having a length of 300 mm and a width of 15 mm were subjected to a 20 g load and were moved back and forth 150 times on a stainless steel pin with a diameter of 5 mm to cause friction. The degree of scratches generated on the friction surface of the film was visually determined to evaluate the abrasion resistance. At this time, the film of polyester composition (8) was evaluated using three ranks: ○ if there were almost no or very few scratches, × if there were many scratches, and △ if there was a moderate amount of scratches. Except for , all other films were rated ○. Comparative Example 1 In Example 1, silica fine particles (A) obtained in Example 1
The same operation as in Example 1 was carried out except that the same amount of the ethylene glycol monodispersion of the silica fine particles (C) obtained in Example 3 was used instead of the ethylene glycol monodispersion of the silica fine particles (C). 0.3 inside
Comparative polyester composition containing % by weight (1)
I got it. Using this comparative composition (1), Example 1
A polyester film was formed in the same manner as in Example 1, and the physical properties of this film were evaluated in the same manner as in Example 1. The dispersibility of the particles and the adhesion of the particles to the polyester were good, and the coefficient of static friction was also excellent at 1.0 or less. However, the abrasion resistance evaluation was ×.

【table】

【table】

Claims (1)

[Scope of Claims] 1. A polyester composition comprising a glycol monodispersion of the following silica spherical fine particles added as a raw material for polyester, the fine particles being contained in the polyester in an amount of 0.005 to 2% by weight. Note: The average particle size is in the range of 0.1 to 5 μm, the standard deviation value of the particle size is in the range of 1.0 to 1.5, the amount of silanol groups in the fine particles is 1.0 mmol or more per 1 g of the fine particles, and the surface of the fine particles is coated with a coupling agent. A glycol monodispersion of amorphous spherical silica particles treated with 2 The standard deviation value of the particle diameter of silica spherical fine particles is
The polyester composition according to claim 1, wherein the polyester composition is in the range of 1.0 to 1.3. 3. The polyester composition according to claim 1 or 2, wherein the coupling agent is a silane-based, titanate-based and/or aluminum-based coupling agent. 4 Claim 1, wherein the silica spherical fine particles have glycol bonded to the surface of the fine particles at a rate of 0.003 mmol or more per 1 g of the fine particles.
3. The polyester composition according to 2 or 3.