JP4817648B2 - Polyester composition and molded article comprising the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyester composition together having excellent melt and heat stability and an excellent color, and to provide a polyester molded product. <P>SOLUTION: This polyester composition has a color L<SP>*</SP>value of &ge;70, an a<SP>*</SP>value of -6 to 0, and b<SP>*</SP>value of -2 to 6, when measured according to the L<SP>*</SP>a<SP>*</SP>b<SP>*</SP>color system after the composition is heat-treated at 140&deg;C for 2 hr, wherein the composition contains a mixed dye comprising a polycyclic aromatic blue dye and a polycyclic aromatic violet dye in an amount of 0.1-10 ppm by wt., a titanium compound in an amount of 1-30 ppm by wt., when converted into an amount of a titanium element (Ti), and a phosphorus compound in an amount of 1-80 ppm by wt., when converted into an amount of a phosphorus element (P), and the mixed dye has a weight ratio of the blue dye to the violet dye of 90:10 to 40:60 and a weight reduction starting temperature of &ge;350&deg;C, when measure by a thermobalance in an atmosphere of nitrogen under a condition of a temperature rise rate of 10&deg;C/min. The molded product is given by using the composition. <P>COPYRIGHT: (C)2006,JPO&amp;NCIPI

Description

  The present invention relates to a polyester composition and a molded article comprising the same. More specifically, the present invention relates to a polyester composition having an excellent hue and also having an excellent thermal stability, and a molded article such as a film or fiber made thereof.

  Polyesters are widely used as molded articles such as films, fibers or bottles because they have excellent mechanical properties, heat resistance, weather resistance, electrical insulation resistance and chemical resistance. In the production of these polyesters, a polymerization catalyst is usually used in order to facilitate the polymerization reaction. Various metal compounds are known as the polymerization catalyst. Among them, antimony (Sb) compounds such as antimony trioxide are widely used because they are inexpensive and have high polymerization activity. However, some of the Sb compounds are reduced during the reaction to generate metal Sb and other foreign matters, causing the polymer hue to be darkened and destabilizing the production process. In particular, when formed into a film, there has been a problem that foreign matters deteriorate the flatness of the film surface.

  As polycondensation catalysts other than antimony compounds, titanium compounds such as germanium compounds and tetra-n-butoxy titanium have been widely used. However, since the germanium compound is quite expensive, there is a problem that the production cost of the polyester becomes high. In addition, although titanium compounds can improve the generation of foreign substances such as antimony compounds, they have a high catalytic activity, so that the heat resistance of the resulting polyester is likely to be lowered and different from antimony compounds that are easily colored yellow. There was a problem.

  On the other hand, in order to suppress coloring of polyester, a cobalt compound is added to polyester to suppress yellowing. However, although the cobalt compound can improve the hue (b value) of the polyester, it deposits metallic foreign matter or lowers the melt heat stability of the resulting polyester and is colored yellow. In particular, the coloring due to the melt heat stability is remarkable in a polymer using an antimony compound or a germanium compound as a polymerization catalyst.

  In order to suppress coloring of these polyesters, as a catalyst for producing polyesters, a product obtained by reacting a titanium compound and a phosphite (Patent Document 1) or a complex of a titanium compound and a phosphorus compound It has also been proposed to use (Patent Document 2). According to these methods, the color tone of the obtained polymer can be improved by improving the melt heat stability of the obtained polyester. However, the effect of improving the color tone of the polymer obtained by these methods is merely a reduction in the decrease in melt heat stability due to the titanium compound used as a catalyst, and has not been a fundamental solution.

JP 58-38722 A JP 7-138354 A

  An object of the present invention is to provide a polyester composition having excellent melt heat stability and hue, and a polyester molded article comprising the same.

  As a result of intensive studies to achieve the above object, the present inventors have not only improved the hue of the polymer but also surprisingly melted when a phosphorus compound and a specific dye are used in a specific ratio. The inventors have found that the thermal stability can be improved, and have reached the present invention.

Thus, according to the present invention, the color L ^* value in the L ^* a ^* b ^* color system after heat treatment at 140 ° C. for 2 hours is 70 or more, the color a ^* value is −6 to 0, and the color b ^* value is −. A polyester composition in the range of 2-6,
The composition contains 0.1 to 10 ppm by weight of a mixed dye composed of a polyaromatic blue dye and a polyaromatic purple dye based on the weight of the composition, and the titanium compound is an element of titanium. 1-30 wt ppm in terms of amount (Ti) and 1-80 wt ppm of phosphorus compound in terms of phosphorus element amount (P), and the mixed dye comprises a polyaromatic blue dye and a polyaromatic The weight reduction starting temperature measured with a thermobalance at a heating rate of 10 ° C./min in a nitrogen atmosphere at a weight ratio of 90:10 to 40:60 in the range of 90:10 to 40:60 A polyester composition that is at or above ° C is provided.

（上記式中、Ｒ¹、Ｒ²、Ｒ³及びＲ⁴はそれぞれ同一若しくは異なって、アルキル基又はフェニル基を示し、ｍは１〜４の整数を示し、かつｍが２、３又は４の場合、２個、３個又は４個のＲ²及びＲ³は、それぞれ同一であっても異なっていてもよい。）
で表わされる化合物、または上記一般式（Ｉ）で表わされる化合物と下記一般式（ＩＩ）

［上記式中、ｑは２〜４の整数を表わす。］
で表わされる芳香族多価カルボン酸もしくはその酸無水物とを反応させた生成物であること、組成物中のジエチレングリコール量が下記式（１）
０．５≦ＤＥＧ≦２．０ ・・・（１）
（上記式中、ＤＥＧはジエチレングリコール濃度（ｗｔ％）を示す。）
を満足すること、組成物中の末端カルボキシル基量が、下記式（２）
５≦ＣＯＯＨ≦４０ ・・・（２）
（上記式中、ＣＯＯＨはカルボキシル末端基濃度（ｅｑ／ｔｏｎ）を示す。）
を満足すること、リン元素量（Ｐ）とチタン元素量（Ｔｉ）との重量比（Ｐ／Ｔｉ）が、０．１〜１０の範囲であること、リン元素量（Ｐ）と混合染料との重量比が、０．１〜５０の範囲にあること、窒素雰囲気下中、３００℃で２０分間溶融処理したときの、処理前後のポリエステルの固有粘度差が０．００１〜０．０１ｄｌ／ｇの範囲にあること、ならびに比重が５以上の重金属元素の含有量が、ポリエステル組成物の重量を基準として、高々１０重量ｐｐｍ以下であることを具備するポリエステル組成物も提供される。 According to the present invention, as a preferred embodiment of the polyester composition of the present invention, the phosphorus compound is a phosphonate compound, and the polyester polycondensation reaction catalyst is represented by the general formula (I).

(In the above formula, R ¹ , R ² , R ³ and R ⁴ are the same or different and each represents an alkyl group or a phenyl group, m represents an integer of 1 to 4, and m is 2, 3 or 4) In this case, 2, 3 or 4 R ² and R ³ may be the same or different.)
Or a compound represented by the above general formula (I) and the following general formula (II)

[In the above formula, q represents an integer of 2 to 4. ]
A product obtained by reacting an aromatic polyvalent carboxylic acid represented by the following formula or an acid anhydride thereof, and the amount of diethylene glycol in the composition is represented by the following formula (1):
0.5 ≦ DEG ≦ 2.0 (1)
(In the above formula, DEG represents the diethylene glycol concentration (wt%).)
That the amount of terminal carboxyl groups in the composition is represented by the following formula (2):
5 ≦ COOH ≦ 40 (2)
(In the above formula, COOH represents the carboxyl end group concentration (eq / ton).)
The weight ratio (P / Ti) between the phosphorus element amount (P) and the titanium element amount (Ti) is in the range of 0.1 to 10, the phosphorus element amount (P) and the mixed dye The weight ratio of polyester is in the range of 0.1 to 50, and the difference in intrinsic viscosity of the polyester before and after the treatment when melt-treated for 20 minutes at 300 ° C. in a nitrogen atmosphere is 0.001 to 0.01 dl / g. There is also provided a polyester composition having a content of a heavy metal element having a specific gravity of 5 or more and at most 10 ppm by weight based on the weight of the polyester composition.

  Moreover, according to this invention, the polyester molded article which consists of the above-mentioned polyester composition, especially a polyester film and a polyester fiber are also provided.

  Since the polyester composition of the present invention uses a specific amount of a phosphorus compound and a specific dye, the resulting polyester composition and a polyester molded article using the polyester composition have heat stability associated with the use of cobalt. Therefore, it is possible to combine excellent thermal stability and hue without causing deterioration of properties and occurrence of metallic foreign matter, and its industrial value is extremely high. In particular, a film using the polyester composition of the present invention has excellent thermal stability and hue, and is extremely suitable as an optical film that requires transparency, for example.

The present invention will be described in detail below.
The polyester composition of the present invention comprises 80% by weight or more, preferably 85% by weight or more of polyester, and may be a mixture of resins other than polyester. The polyester in the present invention is polyalkylene terephthalate (for example, polyethylene terephthalate, polytrimethylene terephthalate, polytetramethylene terephthalate, etc.) or polyalkylene naphthalate (polyethylene naphthalate, polytrimethylene naphthalate, polytetramethylene naphthalate). Phthalate and the like), and among these, polyethylene terephthalate and polyethylene naphthalate are preferable. The term “polyethylene terephthalate” as used herein refers to an ethylene terephthalate component comprising an ethylene terephthalate component as a main repeating unit, specifically, 80 mol% or more, preferably 85 mol% or more of all repeating units. The term “polyethylene naphthalate” as used herein refers to an ethylene naphthalate component as a main repeating unit. Specifically, 80 mol% or more, preferably 85 mol% or more of all repeating units are composed of an ethylene naphthalate component. Preferably, it is made of ethylene-2,6-naphthalate. These polyesters may be homopolymers or copolymerized with the third component as long as the effects of the present invention are not impaired. The third component (copolymerization component) includes terephthalic acid (other than polyalkylene terephthalate), 2,6-naphthalenedicarboxylic acid (other than polyalkylene naphthalate), aromatic dicarboxylic acids such as isophthalic acid and phthalic acid. , Aliphatic dicarboxylic acids such as adipic acid, azelaic acid, sebacic acid and decanedicarboxylic acid, alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid, ethylene glycol (in cases other than polyethylene terephthalate and polyethylene naphthalate), trimethylene glycol (In cases other than polytrimethylene terephthalate and polytrimethylene naphthalate), diethylene glycol, tetramethylene glycol (in cases other than polytetramethylene terephthalate and polytetramethylene naphthalate), cyclohexa It can be exemplified glycol dimethanol, etc., and these may be used in combination of two or more kinds thereof may be used alone.

The polyester composition of the present invention has a color L ^* value of 70 or more in the L ^* a ^* b ^* color system after heat treatment at 140 ° C. for 2 hours, a color a ^* value of −6 to 0, and a color b ^* value of − It must be in the range of 2-6. When the color L ^* value is lower than the lower limit, the lightness of the polyester composition is low, and the effect of improving the hue by the dye is hardly exhibited. Further, when the color a ^* value is smaller than the lower limit, the polyester composition has a strong green color, and when it is larger than the upper limit, the red color becomes strong. Furthermore, when the color b ^* value is smaller than the lower limit, the polyester composition has a strong bluish color, and when the color b ^* value is larger than the upper limit, the yellowish color becomes strong. The color L * value is preferably 75 or more, more preferably 80 or more. The color a * value is preferably in the range of -5 to 0, more preferably in the range of -4 to 0. Furthermore, the color b * value is preferably in the range of −2 to 5, and more preferably in the range of −1 to 4. The color value includes the type and amount of the color adjusting agent added to the polyester composition, the type and amount of the catalyst and phosphorus compound used in the polyester production process, and the temperature conditions received in the polyester production process and the subsequent molding process. It can be adjusted by

  One feature of the present invention is that a specific amount of a specific dye (hereinafter sometimes referred to as a color adjusting agent) is used so that the hue of the resulting polymer can be improved. The dye used in the present invention is a mixed dye of an organic polyaromatic blue dye and a polyaromatic purple dye.

  The ratio of the mixed dye contained in the polyester composition of the present invention is in the range of 0.1 to 10 ppm by weight based on the weight of the composition. When the ratio in the composition is less than the lower limit, the yellowishness of the polyester composition becomes strong, and the effect of improving the thermal stability by the dye becomes poor. On the other hand, when the upper limit is exceeded, the effect of improving the thermal stability by the dye is saturated, the lightness is further weakened, and the blackness and the redness become stronger. The ratio in the preferable composition is preferably in the range of 0.3 to 9 ppm by weight, and more preferably in the range of 0.5 to 8 ppm by weight.

  The mixed dye used in the present invention has a weight loss starting temperature of 350 ° C. or higher measured with a thermobalance in a nitrogen atmosphere at a heating rate of 10 ° C./min. Here, the weight reduction start temperature measured with a thermobalance is the weight reduction start temperature (T1) described in JIS K-7120. When the weight loss starting temperature is less than the lower limit, the effect of improving the thermal stability by the dye is not exhibited, and the dye itself is decomposed, thereby impairing the thermal stability of the resulting polyester composition. More preferably, the weight reduction starting temperature is 400 ° C. or higher.

  The mixed dye used in the present invention is required to have a weight ratio of 90:10 to 40:60 of the polyaromatic blue dye and the polyaromatic purple dye. Here, the polyaromatic ring-based blue dye is one that is indicated as “Blue” among commercially available color adjusting agents, and specifically, the maximum absorption wavelength in the visible light spectrum in the solution. Is about 580 to 620 nm. In addition, the polyaromatic violet dye is the one described as “Violet” among commercially available color adjusting agents, and specifically has a maximum absorption wavelength in a visible light absorption spectrum in a solution. It is about 560 to 580 nm.

  These dyes are preferably oil-soluble dyes, and specific polyaromatic ring-based blue dyes include C.I. I. Solvent Blue 11, C.I. I. Solvent Blue 25, C.I. I. Solvent Blue 35, C.I. I. Solvent Blue 36, C.I. I. Solvent Blue 45 (Telasol Blue RLS), C.I. I. Solvent Blue 55, C.I. I. Solvent Blue 63, C.I. I. Solvent Blue 78, C.I. I. Solvent Blue 83, C.I. I. Solvent Blue 87, C.I. I. Solvent Blue 94 and the like. Similarly, examples of the polyaromatic ring-based purple dye include C.I. I. Solvent Violet 8, C.I. I. Solvent Violet 13, C.I. I. Solvent Violet 14, C.I. I. Solvent Violet 21, C.I. I. Solvent Violet 27, C.I. I. Solvent Violet 28, C.I. I. Solvent Violet 36 etc. are mentioned.

In the weight ratio of the polyaromatic blue dye and the polyaromatic purple dye, if the polyaromatic blue dye is excessively large, the color a ^* value of the resulting polyester composition becomes small and green On the other hand, if the polyaromatic blue dye is excessively small, the color a ^* value increases and a red color is exhibited. The preferred weight ratio of both is in the range of 80:20 to 50:50.

  In the present invention, the timing of adding the mixed dye is not particularly limited, but it is preferable to add it at any stage until the polymerization reaction is completed. In particular, it is preferable to add the dye after the esterification reaction or the transesterification reaction is completed because the thermal stability is more easily improved.

  The polyester composition of the present invention must contain a phosphorus compound as a stabilizer in an amount of 1 to 80 ppm by weight in terms of the amount of phosphorus element (P) based on the weight of the composition. If the amount of the phosphorus compound is less than the lower limit, a sufficient effect of improving the melt heat stability cannot be obtained. On the other hand, if the amount exceeds the upper limit, the softening point of the polyester composition may be lowered and the thermal stability may be inferior. A preferable phosphorus element amount (P) is in the range of 5 to 60 ppm by weight, particularly 10 to 50 ppm by weight.

（上記式中、Ｒ^５、Ｒ^６およびＲ^７はそれぞれ炭素数原子数１〜４のアルキル基を示し、Ｘは−ＣＨ_２−または―ＣＨ(Ｙ)を示す（Ｙは、ベンゼン環を示す）） As a phosphorus compound used by this invention, the phosphonate compound represented by the following formula | equation (III) is preferable.

(In the above formula, R ⁵ , R ⁶ and R ⁷ each represents an alkyl group having 1 to 4 carbon atoms, X represents —CH ₂ — or —CH (Y) (Y represents a benzene ring) ))

  Particularly preferred phosphonate compounds are carbomethoxymethanephosphonic acid, carboethoxymethanephosphonic acid, carbopropoxymethanephosphonic acid, carboptoxymethanephosphonic acid, carbomethoxy-phosphono-phenylacetic acid, carboethoxy-phosphono-phenylacetic acid, carboprotoxy. Dimethyl, diethyl, dipropyl and dibutyl esters of phosphono-phenylacetic acid and carbobutoxy-phosphono-phenylacetic acid.

These phosphonate compounds exhibit a particularly excellent thermal stability improvement effect in combination with the mixed dye and the titanium catalyst as compared with the phosphorus compounds usually used as stabilizers.
These phosphorus compounds may be added at any time after the transesterification reaction is substantially completed, for example, under atmospheric pressure before starting the polycondensation reaction, under reduced pressure after starting the polycondensation reaction, It may be added after the end of the polycondensation reaction or after the end of the polycondensation reaction, that is, after the polymer is obtained.

  Since the polyester composition of the present invention uses a specific amount of a phosphorus compound and a specific mixed dye, even if another polyester composition, for example, cobalt is used in combination, a polyester composition using only cobalt. Compared with, thermal stability can be improved. Preferably, from the viewpoint that the effects of the present invention can be exhibited to the maximum, a titanium compound that is soluble in a polymer can be catalyzed without using a compound containing a heavy metal element having a specific gravity of 5 or more, such as a cobalt compound. It is preferable that it is the polyester composition used as. The specific ratio of the heavy metal element having a specific gravity of 5 or more is preferably at most 10 ppm by weight in terms of the amount of metal element, based on the weight of the polyester composition. When the ratio of the heavy metal element exceeds the upper limit, the thermal stability is lowered.

As the polymerization catalyst used in the present invention, a titanium compound can be used because precipitation of foreign matters caused by the catalyst can be suppressed, and particularly the above-mentioned L ^* value can be increased. There is a need.

  The titanium compound used as the polymerization catalyst in the present invention is not particularly limited as long as it is soluble in the polymer, and is a general titanium compound as a polyester polycondensation catalyst, such as titanium acetate and tetra-n-butoxy titanium. Is mentioned. Among these, a compound represented by the following formula (I) or a compound represented by the following formula (I) is reacted with an aromatic polycarboxylic acid represented by the following formula (II) or an anhydride thereof. The product is preferred.

（上記式中、Ｒ¹、Ｒ²、Ｒ³及びＲ⁴はそれぞれ同一若しくは異なって、アルキル基又はフェニル基を示し、ｍは１〜４の整数を示し、かつｍが２、３又は４の場合、２個、３個又は４個のＲ²及びＲ³は、それぞれ同一であっても異なっていてもどちらでもよい。）

(In the above formula, R ¹ , R ² , R ³ and R ⁴ are the same or different and each represents an alkyl group or a phenyl group, m represents an integer of 1 to 4, and m is 2, 3 or 4) In this case, 2, 3 or 4 R ² and R ³ may be the same or different from each other.)

（上記式中、ｑは２〜４の整数を表わす）

(In the above formula, q represents an integer of 2 to 4)

  The tetraalkoxide titanium represented by the above formula (I) is not particularly limited as long as R is an alkyl group or a phenyl group. Among them, tetraisopropoxy titanium, tetrapropoxy titanium, tetra-n-butoxy titanium, tetra Ethoxy titanium and tetraphenoxy titanium are preferred. As the aromatic polyvalent carboxylic acid represented by the above formula (II), phthalic acid, trimellitic acid, hemimellitic acid, and pyromellitic acid are preferable. The aromatic polyvalent carboxylic acid represented by the general formula (III) may be an anhydride thereof. In order to react the titanium compound with the aromatic polyvalent carboxylic acid, the aromatic polyvalent carboxylic acid or a part of the anhydride thereof is dissolved in a solvent, and the titanium compound is added dropwise to the solution at a temperature of 0 to 200 ° C. What is necessary is just to make it react for 30 minutes or more at temperature.

  The polyester composition of the present invention contains 1 to 30 ppm by weight of the titanium compound soluble in the aforementioned polymer in terms of the amount of titanium element (hereinafter sometimes referred to as Ti) based on the weight of the composition. It is necessary to. A preferable amount of the titanium element is 2 to 20 ppm by weight, particularly 5 to 15 ppm by weight. When the titanium element amount is less than the lower limit, the productivity of the polyester is lowered, and a polyester having a desired molecular weight cannot be obtained. On the other hand, when the amount of the titanium element exceeds the upper limit, the thermal stability of the resulting polyester composition is lowered, the molecular weight during molding into a film or the like is greatly reduced, and a molded product having desired mechanical properties. Cannot be obtained. In addition, the titanium metal element soluble in the polymer referred to here is a titanium compound used as a transesterification reaction catalyst and a titanium used as a polycondensation reaction catalyst in the case of performing a first stage reaction by transesterification. The sum of the compounds is shown.

  The weight ratio (P / Ti) of the titanium compound and phosphorus compound contained in the polymer is preferably in the range of 0.1 to 10, more preferably 0.5 to 9, and particularly preferably 1 to 8. When (P / Ti) is less than the lower limit, the hue of the resulting polymer is yellowish, whereas when (P / Ti) exceeds the upper limit, the polymerization reactivity of the polyester may be extremely reduced.

  The polyester in the present invention may be, for example, via an esterification method using terephthalic acid and ethylene glycol as raw materials, or a transesterification method using terephthalic acid ester-forming derivatives represented by dimethyl terephthalate and ethylene glycol as raw materials. It may be via. Among these, a production method via a transesterification reaction in which 80 mol% or more of all dicarboxylic acid components used as raw materials is dialkyl terephthalate or dialkyl naphthalate is preferable. When dialkyl terephthalate or dialkyl naphthalate is used as a raw material, there is an advantage that the phosphorus compound added as a stabilizer during the polycondensation reaction is less scattered than the production method using terephthalic acid or naphthalene dicarboxylate as a raw material. . In addition, among the production methods using dialkyl terephthalate or dialkyl naphthalate as a raw material, the addition amount of the titanium compound can be reduced. Therefore, at least a part of the titanium compound is added before the transesterification reaction is started, A production method in which two catalysts of the condensation reaction catalyst are also used is preferable.

  Moreover, in this invention, since the addition amount of a titanium compound can be reduced more, it is preferable to implement transesterification under the pressurization of 0.05-0.20 MPa. If the pressure during the transesterification reaction is less than 0.05 MPa, it is difficult to accelerate the reaction by the catalytic action of the titanium compound. On the other hand, if it exceeds 0.20 MPa, a large amount of diethylene glycol is likely to be generated as a by-product. Therefore, characteristics such as thermal stability of the obtained polymer are likely to be deteriorated.

  In the polyester composition of the present invention, the proportion of diethylene glycol contained is preferably in the range of 0.5 to 2.0 wt% based on the weight of the composition. When the proportion of diethylene glycol is less than the lower limit, the crystallinity of the polymer itself becomes too high, and for example, breakage or the like is likely to occur when forming into a film. On the other hand, if the upper limit is exceeded, the heat resistance tends to be impaired. Although it is generally considered that heat resistance is inferior when the diethylene glycol concentration is high, the polyester containing the mixed dye of the present invention has a large change depending on the amount of diethylene glycol, and stipulates the diethylene glycol concentration more strictly than handling for general polyester. It is preferable to do. A more preferable range is a proportion of diethylene glycol in the range of 0.6 to 1.6 wt%, and further 0.7 to 1.4 wt%.

  The polyester composition of the present invention preferably has a carboxyl end group concentration in the range of 5 to 40 eq / ton. Carboxyl end groups are generated by the degradation of the polyester chain, but when the carboxyl end group concentration is higher than the upper limit, for example, the polymer itself tends to decompose in the remelting step when molding, It is necessary to prepare a process such as solid phase polymerization, which may be uneconomical. The range of the carboxyl end group concentration is more preferably 5 to 35 eq / ton, still more preferably 5 to 30 eq / ton.

  The intrinsic viscosity (ο-chlorophenol, 35 ° C.) of the polyester resin composition of the present invention is preferably in the range of 0.50 to 0.80, more preferably 0.55 to 0.75, particularly 0.60. A range of 0.70 is preferred. If the intrinsic viscosity is less than the lower limit, the impact resistance of the molded product, for example, a film may be insufficient. On the other hand, if the intrinsic viscosity exceeds the upper limit, it is necessary to raise the intrinsic viscosity of the raw polymer excessively, which is uneconomical.

  The polyester composition of the present invention is, for example, in the case of molding into a film, in order to improve handleability, 0.05 to 5.0 wt. About% may be added. At this time, from the viewpoint of maintaining the excellent transparency which is a feature of the polyester composition of the present invention, it is preferable that the inert particles to be added have a small particle size and the addition amount is as small as possible. Inactive particles to be added include colloidal silica, porous silica, titanium oxide, calcium carbonate, calcium phosphate, barium sulfate, alumina, zirconia, kaolin, composite oxide particles, crosslinked polystyrene, acrylic crosslinked particles, methacrylic crosslinked particles And silicone particles. Further, various functional agents such as an antioxidant, a heat stabilizer, a viscosity modifier, a plasticizer, a nucleating agent, and an ultraviolet absorber may be added according to the requirements of each molded product such as a film, fiber, and bottle.

Finally, the polyester film provided in the present invention will be described.
The film of the present invention can be obtained by using the above-described polyester composition of the present invention as a raw material and extruding it in a molten state into a sheet. Preferably, since the obtained film can have dimensional stability and strength, a uniaxially oriented polyester film stretched in a uniaxial direction and a biaxially oriented polyester film stretched in an orthogonal biaxial direction are preferred. The biaxially oriented polyester film will be described in more detail with reference to an example.

  After drying the pellet of the polyester composition of the present invention within a temperature range of (Tc) to (Tc + 40) ° C. (Tc is the crystallization temperature when the polyester is heated) for 1 to 3 hours, (Tm) to (Tm + 70) ° C. A substantially amorphous polyester sheet (unstretched film) is melt-extruded into a sheet within a temperature range of (Tm is the melting point of the polyester) and then solidified on a rotating cooling drum having a surface temperature of 20 to 40 ° C. Get. The unstretched film is then stretched in the machine or transverse direction. Preferably, the film is stretched in the longitudinal direction and then stretched in the transverse direction, the so-called longitudinal and transverse sequential biaxial stretching method, the stretching method in which this order is reversed, or the simultaneous biaxial stretching method in which biaxial centrifugation is performed at the same time. Stretch in the axial direction. The temperature at the time of stretching (heat setting temperature) is (Tg-10) to (Tg + 70) ° C. (Tg is the secondary transition temperature of the polyester), and the draw ratio is appropriately adjusted according to the requirements of the intended use. However, it is preferable to select from a range of 2.5 times or more in the uniaxial direction, further 3 times or more, and an area magnification of 8 times or more, more preferably 10 to 30 times.

  When producing the polyester film of the present invention, there are no restrictions on the shape of the slit die used, the melting temperature, the draw ratio, the heat setting temperature, etc., and the laminated film using a single layer film or coextrusion technology, etc. Any of these can be employed.

  In the polyester film of the present invention thus obtained, the polyester composition constituting the film has a very excellent hue, and there are few metal deposits and excellent transparency. In addition, the polyester film of this invention can say the same thing as having demonstrated with the polyester composition of the above-mentioned this invention, and its manufacturing method.

  The polyester fiber of the present invention can be produced by a method known per se by using the above-described polyester composition of the present invention as a raw material. Specifically, the above-described polyester composition of the present invention is extruded in a rod shape from a die in a molten state, taken at a spinning speed of about 400 to 5000 m / min, and if necessary, produced by stretching in the fiber axis direction. it can.

  The polyester fiber of the present invention thus obtained has an extremely excellent hue and thermal stability in the polyester composition constituting the fiber. In addition, it can be said that the polyester fiber of this invention is the same as having demonstrated with the polyester composition of the above-mentioned this invention and its manufacturing method similarly to a film.

Hereinafter, the present invention will be further described by examples. The characteristics of the polyester composition were measured and evaluated by the following methods.
(1) Intrinsic viscosity (unit: dl / g):
The intrinsic viscosity (IV) of the polyester chip was determined from the viscosity value measured at 35 ° C. in an orthochlorophenol solution.
(2) DEG concentration (DEG):
The polyester chip was dissolved in a CDCl ₃ / CF ₃ COOD mixed solvent and measured by ¹ H-NMR.
(3) Carboxyl end group concentration (COOH):
Polyester chips were dissolved by heating in benzyl alcohol, and phenol red and aqueous NaOH solution were added dropwise. The carboxyl group concentration was calculated from the amount of aqueous NaOH solution at the midpoint where the solution turned from yellow to red. The measurement was performed at room temperature.
(4) Metal element concentration:
Titanium element, phosphorus element, cobalt element, and antimony element concentration were measured by using a fluorescent X-ray measuring apparatus 3270 manufactured by Rigaku Corporation by heating and melting a polyester chip to form a circular disk. When inert particles were included as a lubricant, the same measurement was performed after removing the inert particles by a centrifugal separation treatment in a solvent in advance.
(5) Color tone (L ^* value, a ^* value, b ^* value):
After the polyester chip sample was dried at 140 ° C. for 2 hours, it was placed on a white standard plate for color difference adjustment, and the hunters L ^* and b ^* on the plate surface were used with a color machine CM-7500 type color machine. Measured. The L value is an indicator of lightness, and the larger the value, the higher the lightness, and the b value, the greater the value, the greater the degree of yellowing.
(6) Thermal stability of polyester:
A polyester chip dried at 160 ° C. for 1 hour is placed in a glass flask, and then immersed in a salt bath maintained at 300 ° C., and then stirred and held in a molten state for 20 minutes under a nitrogen stream. The intrinsic viscosity (IV) was measured, and the intrinsic viscosity difference (IV difference) before the drying treatment was determined.
(7) Metal deposit:
A solution obtained by adding 0.1 g of a polyester chip to a dissolving solution (mixed solution of hexafluoroisopropanol / chloroform = 50/50% by weight) was dissolved with a membrane filter (filtration area = 7.1 cm ² ) made of 3 μm pore size Teflon (registered trademark). Filter. The dried filter paper was counted using a scanning electron microscope (S3100, manufactured by Hitachi, Ltd.), and the number of particles on the filter paper was counted, and the number of particles per 1 cm ² was calculated from the observation area.
(8) Weight loss start temperature of mixed dye:
According to JIS K-7120, the measurement was performed with a thermobalance in a nitrogen atmosphere under a temperature rising rate of 10 ° C./min. In addition, the weight reduction start temperature here means the weight reduction start temperature (T1) in JIS K-7120.
(9) Film haze:
The polyester chip sample was heat-treated in a dryer at 150 ° C. for 6 hours, dried, melt-extruded in a sheet form from a melt extruder onto a rotary cooling drum at 290 ° C., rapidly cooled and solidified, and 100 μm thick Create a stretched film (sheet). A site where no scratches or the like were generated on the surface of the obtained unstretched sheet was sampled and measured with a Nippon Denshoku Industries Co., Ltd. turbidimeter (HDH-1001DP).

[Reference Example 1] (Method for producing titanium trimellitic acid)
0.8 parts by weight of trimellitic anhydride is dissolved in 2.5 parts by weight of ethylene glycol, and 0.7 parts by weight of titanium tetrabutoxide in this ethylene glycol solution (0.5 mol% based on the molar amount of trimellitic anhydride) The reaction system was kept at 80 ° C. for 60 minutes in air at normal pressure to react titanium tetrabutoxide with trimellitic anhydride to obtain a reaction product (TMT). Thereafter, the reaction system was cooled to room temperature, 15 parts by weight of acetone was added, and the precipitate was no. After filtering through 5 filter papers, it was dried at a temperature of 100 ° C. for 2 hours. The titanium content of the obtained reaction product was 11.2% by weight.

[Reference Example 2] Preparation of dyes The dyes shown in Table 1 were measured for the thermogravimetric decrease starting temperature in a powder state. The results are shown in Table 1. When these dyes were added to the polyester production process, they were prepared by dissolving or dispersing at a temperature of 100 ° C. in a glycol solution used as a raw material so as to have a concentration of 0.1% by weight.

なお、表１中の各種染料は、クラリアントジャパン株式会社や有本化学工業株式会社から入手することができる。

Various dyes in Table 1 can be obtained from Clariant Japan Co., Ltd. or Arimoto Chemical Industry Co., Ltd.

[Examples 1 and 2]
After charging SUS (stainless steel) container capable of pressure reaction with 100 parts of dimethyl terephthalate and 70 parts of ethylene glycol, and adding tetra-n-butyl titanate as a transesterification catalyst to the amount shown in Table 2. The ester exchange reaction was carried out while increasing the pressure from 140 ° C. to 240 ° C. under a pressure of 0.07 MPa. Thereafter, triethylphosphonoacetate and a dye were added so as to have the amounts shown in Table 2 to complete the transesterification reaction. The reaction product was transferred to a polymerization vessel, heated to 290 ° C., and subjected to a polycondensation reaction in a high vacuum of 0.2 mmHg or less to obtain a polyester composition having an intrinsic viscosity of 0.62. Table 2 shows the properties of the obtained polyester composition and the unstretched film obtained using the polyester composition.

[Example 3]
A polyester resin composition and an unstretched film were obtained in the same manner as in Example 1 except that the titanium compound and the addition amount thereof were changed to titanium trimellitic acid. Table 2 shows the properties of the obtained polyester composition and the unstretched film obtained using the polyester composition.

[Comparative Examples 1-5]
A polyester resin composition and an unstretched film were obtained in the same manner as in Example 1 except that the titanium compound, phosphorus compound and color adjusting agent were changed as shown in Table 2. These characteristics are shown in Table 2.

[Comparative Examples 6 and 7]
A polyester resin composition and an unstretched film were obtained in the same manner as in Example 1 except that an antimony compound was used as the polycondensation catalyst instead of the titanium compound and the color adjusting agent was changed as shown in Table 2. The characteristics are shown in Table 2.

Here, in Table 2, TBT is tetra-n-butoxy titanium, TMT is trimellitic titanium, Sb ₂ O ₃ is antimony trioxide, PA is normal phosphoric acid, P is phosphorus element amount (ppm), and Ti is titanium. Element amount (ppm), IV is intrinsic viscosity (dl / g), DEG is diethylene glycol amount (wt%), COOH is terminal carboxyl group amount (eq / ton), Col is color tone, L ^* is L ^* value, a ^{* Indicates an} a ^* value, and b ^* indicates a b ^* value.

  As is clear from Table 2, Examples 1 to 3 were excellent in thermal stability and hue, and had less foreign matter than Comparative Example 1 in which no mixed dye was added. In addition, heavy metals having a specific gravity of 5 or more were not detected at all levels except Comparative Examples 6 and 7. Moreover, in Comparative Examples 6 and 7, the hue is changed by using a mixed dye, but the heat resistance is not improved, and from this, the combined use of a titanium compound and a mixed dye as a catalyst is It can be confirmed that the heat resistance is improved.

Claims (11)

Polyester having a color L ^* value of 70 or more, a color a ^* value of −6 to 0, and a color b ^* value of −2 to 6 in the L ^* a ^* b ^* color system after heat treatment at 140 ° C. for 2 hours A composition comprising:
The composition contains 0.1 to 10 ppm by weight of a mixed dye composed of a polyaromatic blue dye and a polyaromatic purple dye based on the weight of the composition, and the titanium compound is an element of titanium. 1-30 wt ppm in terms of amount (Ti) and 1-80 wt ppm of phosphorus compound in terms of phosphorus element amount (P), and the mixed dye comprises a polyaromatic blue dye and a polyaromatic The weight reduction starting temperature measured with a thermobalance at a heating rate of 10 ° C./min in a nitrogen atmosphere at a weight ratio of 90:10 to 40:60 in the range of 90:10 to 40:60 A polyester composition characterized by having a temperature of ℃ or higher.   The polyester resin composition according to claim 1, wherein the phosphorus compound is a phosphonate compound. Polyester polycondensation reaction catalyst is a compound represented by the following general formula (I), or a compound represented by the following general formula (I) and an aromatic polyvalent carboxylic acid represented by the following general formula (II) or its acid anhydride The polyester resin composition according to claim 1, which is a reaction product with a product.

(In the above formula, R ¹ , R ² , R ³ and R ⁴ each represents an alkyl group or a phenyl group, and m represents an integer of 1 to 4.)

(In the above formula, q represents an integer of 2 to 4.)   The polyester composition according to claim 1, wherein the weight ratio (P / Ti) of the phosphorus element amount (P) and the titanium element amount (Ti) is in the range of 0.1 to 10. The polyester composition according to claim 1, wherein the amount of diethylene glycol and the amount of terminal carboxyl groups in the composition satisfy the following formula.
0.5 ≦ DEG ≦ 2.0 (1)
5 ≦ COOH ≦ 40 (2)
(In the above formula, DEG represents the diethylene glycol concentration (wt%) and COOH represents the carboxyl end group concentration (eq / ton).)   The polyester composition according to claim 1, wherein the weight ratio of the phosphorus element amount (P) to the mixed dye is in the range of 0.1 to 30.   The polyester composition according to claim 1, wherein the difference in intrinsic viscosity of the polyester before and after the treatment when melt-treated at 300 ° C for 20 minutes in a nitrogen atmosphere is in the range of 0.001 to 0.01 dl / g.   The polyester composition according to claim 1, wherein the content of the heavy metal element having a specific gravity of 5 or more is at most 10 ppm by weight based on the weight of the polyester composition.   A polyester molded article comprising the polyester composition according to any one of claims 1 to 8.   The polyester molded article according to claim 9, which is a polyester film.   The polyester molded article according to claim 9, which is a polyester fiber.