JP2002363392A - Polyester composition and film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyester composition which excels in moldability, heat resistance, and transparency and is particularly suited in the optical application, and a film. SOLUTION: The polyester composition comprises 0.05-5 wt.% composite oxide particles which contain at least one element to be selected from the group consisting of Ca, Zn, Sb, Zr, B, Na, K, Li, and F and have an average particle diameter of 0.3-5 μm, a refractive index of 1.47-1.6, a pH of its 5 wt.% aqueous dispersion of >=8 and, simultaneously, a composition meeting three formulae of formula (1): 26 <= amount of Si element <= 37 (wt.%), formula (2): 0 <= amount of Al element <= 13 (wt.%), and formula (3): 32 <= amount of Si element + amount of Al element <= 40 (wt.%), and a polyester in which >=90 mol% the constituting units are ethylene terephthalate units or ethylene naphthalate units.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a polyester composition and a film, and more particularly, to moldability, heat resistance, and the like.
The present invention relates to a polyester composition and a film which are excellent in slipperiness and transparency and are suitably used for optical applications and magnetic materials.

[0002]

2. Description of the Related Art Polyester films are widely used in packaging applications, optical applications, etc. because of their excellent mechanical properties, thermal properties and transparency. For example, there are transparent films for packaging foods and the like, protective films for light sources, reflectors, molded products and the like.

[0003] However, since particles are added to the polyester film in order to suppress shaving during molding, problems such as coloring by particles, generation of voids, and whitening due to crystallization occur. To solve this, various studies have been made, such as reducing the amount of particles added, reducing the particle size, suppressing the generation of voids due to surface treatment and agglomerated particles, and suppressing crystallization under film forming conditions. Is not always enough.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, and is excellent in moldability, heat resistance and transparency, and is particularly suitable for optical applications. Is to provide.

[0005]

SUMMARY OF THE INVENTION The object of the present invention is to provide at least one element selected from the group consisting of Ca, Zn, Sb, Zr, B, Na, K, Li and F. The particle diameter is 0.3 to 5 μm, and the refractive index is 1.47.
Composite oxide particles having a pH of 8 or more as a water dispersion of from 1.6 to 5% by weight and having a composition satisfying the following formulas (1) to (3): 0.05 to 5% by weight And the structural unit 9
This is achieved by a polyester composition containing at least 0 mol% of a polyester which is an ethylene terephthalate unit or an ethylene naphthalate unit.

26 ≦ Si element amount ≦ 37 (% by weight) (1) 0 ≦ Al element amount ≦ 13 (% by weight) (2) 32 ≦ Si element amount + Al element amount ≦ 40 (% by weight) ) ・ ・ ・ (3)

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The polyester in the present invention is:
From the viewpoint of controlling the refractive index, 90 mol% or more, more preferably 95 mol% or more of the constituent units are ethylene terephthalate units or ethylene naphthalate units.

Further, other components may be copolymerized or blended with the polyester as long as the effects of the present invention are not impaired.

As the copolymerization component, isophthalic acid, 2,2
6-naphthalenedicarboxylic acid, adipic acid, trimethyladipic acid, sebacic acid, malonic acid, dimethylmalonic acid, succinic acid, glutaric acid, maleic acid, itaconic acid, pimelic acid, 2,2-dimethylglutaric acid, azelaic acid, Fumaric acid, 1,3-cyclopentanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 1,4
-Cyclohexanedicarboxylic acid, 1,4-naphthalic acid, diphenic acid, 4,4'-oxybenzoic acid, 2,5
Polyfunctional carboxylic acids such as naphthalenedicarboxylic acid, diphenylethanedicarboxylic acid, trimellitic acid and ester derivatives thereof, diethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, 1,3-propane glycol, 1,3-
Butanediol, 1,4-butanediol, 1,3 pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-
Nonanediol, 1,10-decanediol, 2,4-
Dimethyl-2-butyl-1,3-propanediol, 2
-Ethyl-2-isobutyl-1,3-propanediol, 3-methyl-1,5-pentanediol, 2,2,
4-trimethyl-2-hexanediol, 1,2-cyclohexanedimethanol, 2,2,4,4-tetramethyl-1,3-cyclobutanediol, 4,4′-thiodiphenol, bisphenol A, 4,4 '-Methylenediphenol, 4,4'-(2-normornylidene) diphenol, 4,4'-dihydroxybiphenol, o
-, M-, and p-dihydroxybenzene, 4,4 '
-Isopropylidenephenol, 4,4'-isopropylidenebis (2,6-dichlorophenol), 2,5-
Naphthalene diol, p-xylene diol, cyclopentane-1,2-diol, cyclohexane-1,2-
Glycol components such as diols and cyclohexane-1,4-diols can be mentioned. Among them, dicarboxylic acids such as isophthalic acid, naphthalenedicarboxylic acid, cyclohexanedicarboxylic acid and diphenylethanedicarboxylic acid and ester derivatives thereof, propylene glycol and tetracarboxylic acid Glycol components such as methylene glycol and cyclohexanedimethanol are preferred.

Examples of the blend include homopolyesters other than polyethylene terephthalate, copolymerized polyesters, polycarbonates, acrylic resins, and polyolefins.

The particle diameter of the composite oxide particles used in the present invention is from 0.3 to 5 μm as a primary average particle diameter from the viewpoint of the shape of the projections when formed into a film, workability, transparency and control of the refractive index of the film. It is necessary that the thickness be 0.5 to 3 μm. This primary average particle size is 0.
When the thickness is less than 3 μm, sufficient projections are not formed when the film is formed, so that slipperiness is reduced and workability is reduced. On the other hand, if it exceeds 5 μm, voids tend to be formed during film formation, and the transparency may be impaired.

The content of the composite oxide particles must be 0.05 to 5% by weight, preferably 0.1 to 3% by weight, from the viewpoint of slipperiness and moldability. When the content is less than 0.05% by weight, sufficient projections are not formed when the film is formed, so that slipperiness is reduced and workability is reduced. On the other hand, if the content exceeds 5% by weight, the polymer tends to crystallize, and the transparency may be impaired.

The refractive index of the composite oxide particles is required to be 1.47 to 1.6, and preferably 1.47 to 1.55, for example, from the viewpoint of transparency when formed into a film. If this value is less than 1.47 or exceeds 1.6, the difference in the refractive index from the polyester will increase, and the transparency may be impaired.

The pH of the composite oxide particles in a 5% by weight aqueous dispersion (water slurry) must be 8 or more, preferably 9 to 11 in view of the affinity for polyester. It is. When the pH is lower than 8, the affinity with the polyester decreases, and the formation of voids and the formation of coarse particles due to agglomeration are likely to occur, which may impair the transparency.

It is necessary that the composition of the composite oxide satisfies the expressions (1) to (3) from the viewpoint of controlling the refractive index. 26 ≦ Si element amount ≦ 37 (% by weight) (1) 0 ≦ Al element amount ≦ 13 (% by weight) (2) 32 ≦ Si element amount + Al element amount ≦ 40 (% by weight) (3) If the content of the Si element is less than 26% by weight or more than 37% by weight, it becomes difficult to obtain composite oxide particles having a desired refractive index. On the other hand, if the Al element content exceeds 13% by weight, the melting temperature becomes high, which is disadvantageous in cost, and it is difficult to obtain a target refractive index. Regarding the total content of such Si element and Al element, 3
If the amount is less than 2% by weight, heat resistance may be reduced and the polymer may be colored. If the amount is more than 40% by weight, the melting temperature becomes high, and the melting operation and the control of the refractive index become difficult.

In addition, the component contained in the composite oxide particles is at least one element selected from the group consisting of Ca, Zn, Sb, Zr, B, Na, K, Li and F. By including these elements, the refractive index of the composite oxide particles can be easily controlled. The total content of these elements is 8.5 with respect to the composite oxide particles.
To 28% by weight, particularly Zn, B,
Ca, Na, K, Zr and Sb are preferably contained as oxides. In addition, metal compounds such as Ti, Ba, S, F
e, Mo, Mn, Cr, Ni, Co, Cu and the like may be contained in trace amounts.

The composite oxide particles are preferably amorphous in terms of transparency and refractive index.

The composite oxide particles are, for example, silica sand,
Raw materials such as aluminum hydroxide, boric acid, lime, zinc white, antimony oxide, zirconia, aluminum fluoride, and calcium fluoride are mixed so as to have a desired composition.
After melting at 300 to 2,000 ° C., it can be obtained by cooling, pulverizing and classifying.

Such composite oxide particles have various surfaces as long as the transparency is not impaired, from the viewpoint of improving dispersibility, improving affinity with polyester, and suppressing irregular reflection of light at the interface between the particles and polyester. A treating agent may be used.

Further, other particles, for example, various externally added particles such as fine alumina and colloidal silica, and internally precipitated particles using a catalyst residue may be used as long as the effects of the present invention are not impaired. I do not care.

In producing the polyester composition of the present invention, various reaction catalysts and coloring inhibitors can be used. Examples of the reaction catalyst include alkali metal compounds, alkaline earth metal compounds, zinc compounds, and lead compounds. Examples of a coloring inhibitor such as a compound, a manganese compound, a cobalt compound, an aluminum compound, an antimony compound, and a titanium compound include a phosphorus compound. Preferably, it is preferable to add an antimony compound, a germanium compound, or a titanium compound as a polymerization catalyst at any stage before the production of the polyester is usually completed.
As such a method, for example, when a germanium compound is taken as an example, a method of adding a germanium compound powder as it is, or as described in JP-B-54-22234, glyco- And a method in which a germanium compound is dissolved and added to the toluene component. As the germanium compound, for example, germanium dioxide, germanium hydroxide containing crystal water, or germanium alkoxide compounds such as germanium tetramethoxide, germanium tetraethoxide, germanium tetrabutoxide, germanium ethylene glycoloxide, germanium phenolate, germanium β-naphtholate, etc. Phosphorus-containing germanium compounds such as germanium phenoxide compounds, germanium phosphate and germanium phosphite, and germanium acetate. Among them, germanium dioxide is preferable. Examples of the antimony compound include, but are not particularly limited to, antimony oxides such as antimony trioxide, and antimony acetate. The titanium compound is not particularly limited, but an alkyl titanate compound such as tetraethyl titanate and tetrabutyl titanate is preferably used.

Hereinafter, a case where germanium dioxide is added as a germanium compound when producing, for example, polyethylene terephthalate will be described. The terephthalic acid component and ethylene glycol are subjected to transesterification or esterification, and then germanium dioxide and a phosphorus compound are added. Thereafter, a particle slurry is added, followed by a polycondensation reaction under a high temperature and a reduced pressure until a constant ethylene glycol content is obtained, thereby obtaining a germanium element-containing polymer. Further, preferably, the obtained polymer is subjected to a solid-phase polymerization reaction under reduced pressure or an inert gas atmosphere at a temperature not higher than its melting point, to reduce the content of acetoadheride, and obtain a predetermined intrinsic viscosity and a carboxyl end group. And the like.

The film of the present invention can be suitably used in either a single layer or a laminate. When another layer (hereinafter, (II) layer) is laminated on a layer (hereinafter, (I) layer) containing (or as a main component of) the polyester composition of the present invention, the polyester of (II) layer is not particularly limited. However, a thermoplastic polymer, a polymer such as a thermosetting polymer may be laminated, polyester, for example, high molecular weight polyethylene terephthalate, polyethylene naphthalate, 2,6-naphthalenedicarboxylic acid copolymerized polyethylene terephthalate,
Examples thereof include polyesters obtained by adding and copolymerizing isophthalic acid copolymerized polyethylene terephthalate, isophthalic acid copolymerized polyethylene naphthalate, butanediol, and diethylene glycol, and preferably have a melting point of 200 to 260 ° C.

Further, (I) layer / (II) layer / (I) layer,
Three layers such as (II) layer / (I) layer / (II) layer may be laminated.

From the viewpoint of transparency, the haze of such a polyester film is preferably 4 or less in a film having a desired thickness. If it exceeds 4, the light transmittance is reduced, and when used for applications such as an optical protective film, the optical properties may be adversely affected.

The method for producing the film of the present invention is not particularly limited. For example, polyester is dried as required, then supplied to a melt extruder, extruded into a sheet from a slit die, and subjected to electrostatic application. In close contact with the casting drum by the method, it is cooled and solidified to obtain an unstretched sheet,
Then, the unstretched sheet is stretched and heat-treated in the longitudinal direction and the width direction of the film to obtain a film having a desired refractive index in the thickness direction. From the viewpoint of film quality, the transverse stretching is preferably performed by a tenter method.After stretching in the longitudinal direction, the film is successively biaxially stretched in the width direction. Axial stretching is preferred. The stretching ratio is 1.5 to 4 times, preferably 1.8 to 3.5 times in each direction. Either the stretching ratio in the longitudinal direction or the stretching ratio in the width direction may be increased, and may be the same. The stretching speed is 1,
2,000% / min to 200,000% / min, and the stretching temperature can be any temperature as long as it is equal to or higher than the glass transition temperature of the polyester and equal to or lower than the glass transition temperature + 80 ° C. ~ 60 ° C is preferred. Further, the film may be subjected to a heat treatment after the biaxial stretching, and this heat treatment can be carried out by various methods, for example, in an oven or on a heated roll. The heat treatment temperature can be any temperature between 120 ° C. and 250 ° C., but is preferably between 150 and 240 ° C. The heat treatment time can be arbitrarily set, but is preferably 0.1 to 6 hours.
It is preferably 0 seconds, more preferably 1 to 20 seconds. The heat treatment may be performed while relaxing the film in the longitudinal direction and / or the width direction, or may be performed under a certain degree of tension. Further, re-stretching may be performed once or more in each direction, and then heat treatment may be performed.

The above-mentioned film of the present invention can be suitably used, for example, for bonding glass members, optical members, protective films for products, base films for magnetic recording media, and the like.

[0028]

The present invention will be described in detail with reference to the following examples. The characteristics were measured and evaluated by the following methods. (1) Measurement of primary average particle diameter After blending the particles with polyester and cutting into ultra-thin slices having a thickness of 0.2 μm, at least 5 particles were measured with a transmission electron microscope.
Observation and measurement were performed on 0 particles. The diameter was calculated by taking the maximum diameter as the diameter of the particle, converting it into a sphere, and then calculating the volume average diameter. (2) Refractive index of composite oxide particles According to JIS-K-0062, a sample plate having the same composition as the composite oxide particles was prepared (the molten raw material material was cast), and sodium D line (589 nm) was used as a light source. ) Was measured with an Appe refractometer. (3) Particle composition X-ray fluorescence spectrometer manufactured by Rigaku Corporation (Model: 3270)
, The elements of Si, Al, B, Zn, Sb, Ca, and Zr were quantified.

For the elements Na, K and Li, atomic absorption spectrometry (manufactured by Hitachi, Ltd .: polarized Zeeman atomic absorption spectrophotometer 18)
0-80. (Frame: acetylene-air).

For the element F, an ion selective electrode method (microprocessor ionalyzer manufactured by ORION RESEARCH Inc.)
Model 901. F ion electrode: ORION RESEARCH Inc. Fluor
ide Electrode Model 94-0. Reference electrode: ORION RESEARCH
Inc. Reference Electrode Model 90-01).

In each case, a calibration curve was prepared for quantification. (4) Measurement of film haze (thickness: 50 μm) Measured by JIS-K-6714 with a haze meter SEP-H-2 from Nippon Seimitsu Kogaku Co., Ltd. (Reference Examples: Particles A to E) Silica sand, calcium oxide, calcium hydroxide, aluminum hydroxide, boric acid, zinc oxide, antimony oxide, zirconia, aluminum fluoride, and calcium fluoride are appropriately mixed so as to have a desired composition. ,
After melting at 1,500 ° C., it is cooled,
Pulverization was performed with a sand mill to obtain composite oxide particles having a desired particle size. Adjustment of the particle size and the like is performed by appropriately adjusting the size and material of the beads, the filling rate, the shape of the stirring blade, and the number of rotations. Finally, wet filtration is performed with a sintered filter having an aperture of 50 μm to remove coarse particles. Removed.

Table 1 shows the composition and physical properties of the particles. Example 1 To 100 kg of dimethyl terephthalate and 64 kg of ethylene glycol, 60 g of magnesium acetate was added as a catalyst, dissolved at 150 ° C., and stirred for 235 minutes.
After the temperature was raised to 0 ° C. to perform a transesterification reaction, the particles A were dispersed in ethylene glycol to form a 10% by weight ethylene glycol slurry, and 3 kg of the particle slurry was added.
Further, 20 g of germanium dioxide as a catalyst and 17 g of phosphoric acid as a heat-resistant stabilizer were added, and a polycondensation reaction was carried out while raising the temperature to 290 ° C. and reducing the pressure to 1 torr or less to obtain a polyethylene terephthalate composition.

The polyethylene terephthalate composition obtained as described above is dried under reduced pressure at 160 ° C. for 4 hours, supplied to a single-screw extruder, discharged from a normal die, and cooled with a mirror cooling drum while applying static electricity. It was solidified to obtain an unstretched film. This unstretched film is stretched 3.0 times in the longitudinal direction at a temperature of 95 ° C., cooled to room temperature, stretched 3.0 times in a width direction at a temperature of 95 ° C., and relaxed at 190 ° C. 3%, 5%
Heat treated for seconds. The film properties obtained are as shown in Table 2. Example 2 Example 1 was repeated except that a particle-free polyethylene terephthalate was obtained as the polymer for the (II) layer in the same manner as in Example 1 and then laminated on both sides of the (I) layer to form a three-layer structure. In the same manner, a laminated film was obtained (the polymer of the layer (I) was the same as that in Example 1). (Example 3) A polymer for the layer (I) was obtained in the same manner as in Example 1 except that the particles B were used instead of the particles A. Further, in the same manner as in Example 2, a polymer for the (II) layer was obtained.

A laminated film was obtained in the same manner as in Example 1 except that the layer (I) was laminated on the layer (II) to form a two-layer structure. (Example 4) A film was obtained in the same manner as in Example 1 except that particle C was used instead of particle A. Example 5 Particle D was used instead of Particle A, the stretching ratio was 2.8 times in the longitudinal direction, 2.8 times in the width direction, and the heat treatment temperature was 2
A laminated film was obtained in the same manner as in Example 2 except that the temperature was changed to 00 ° C. (Example 6) A laminated film was obtained in the same manner as in Example 2 except that particles E were added instead of the particles A, and the heat treatment temperature was set to 200 ° C. (Comparative Examples 1 to 3) Films were obtained in the same manner as in Example 1 except that commercially available silica (particle F, particle G) and alumina (particle H) were used instead of particle A.

[0035]

[Table 1]

[0036]

[Table 2]

[0037]

According to the present invention, a film material excellent in optical properties and suitable for use in bonding glass members, optical members, protective films for products, base films for magnetic recording media, and the like is provided. Can be provided.

Continuing on the front page F-term (reference) 4F071 AA45 AA46 AB18 AE17 AF30 AH03 AH14 BB06 BB08 BC01 4F100 AA06A AA06B AA17A AA17B AA18A AA18B AA25A AA25B AA27A AA27B AA29A A33A02A ABAB DD036 DE086 DE126 DE146 DJ006 DK006 GS00

Claims (6)

[Claims] 1. Ca, Zn, Sb, Zr, B, Na,
At least one selected from the group consisting of K, Li and F
PH of 8 or more as an aqueous dispersion containing various elements, an average particle diameter of 0.3 to 5 μm, a refractive index of 1.47 to 1.6 and 5% by weight, and the following (1) And 0.05 to 5% by weight of composite oxide particles having a composition satisfying the formulas (3) to (3).
A polyester composition containing a polyester in which 90 mol% or more of the constituent units are ethylene terephthalate units or ethylene naphthalate units. 26 ≦ Si element amount ≦ 37 (% by weight) (1) 0 ≦ Al element amount ≦ 13 (% by weight) (2) 32 ≦ Si element amount + Al element amount ≦ 40 (% by weight)・ (3) 2. The polyester composition according to claim 1, wherein the composite oxide particles are amorphous. 3. Ca, Zn, Sb, Zr, B, Na,
At least one selected from the group consisting of K, Li and F
7. The total content of the various elements is 8.
The polyester composition according to claim 1, which is 5 to 28% by weight. 4. A film comprising the polyester composition according to claim 1. 5. A laminated polyester film comprising at least one layer of the film according to claim 4. 6. The film according to claim 4, having a haze of 4% or less, or the laminated polyester film according to claim 5.