JP2000044662A - Polyester polymer and molded product thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject polymer having excellent repeated weathering resistance, rapid color development and fading, high color denseness and easiness e.g. for cast molding and useful e.g. as a dimming lens by using a long-chain aliphatic compound, a dicarboxylic acid and a dihydroxy compound. SOLUTION: This polymer is obtained by reaction between (A) a long-chain aliphatic compound having alcoholic hydroxy groups or carboxylic acids and their ester-forming derivatives at both of the terminals, (B) a dicarboxylic acid or its ester-forming derivative and (C) a dihydroxy compound. It is preferable that the component A comprises a compound expressed by OH(CnH2nO)xH [the relationship between (n) and (x) is 10<(n+1)(x)<300] and the component B comprises an alicyclic dicarboxylic acid, such as cyclohexanedicarboxylic acid and the component C comprises terephthalic acid or isophthalic acid or an ester-forming derivative thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a polyester polymer and a molded product thereof, and more particularly, to transparency,
The present invention relates to a polyester polymer having excellent moldability and having excellent properties as a light control dye carrier, and a molded article thereof.

[0002]

2. Description of the Related Art Conventionally, borosilicate glass or aluminophosphate glass in which silver halide is dispersed has been widely used as an inorganic photochromic material.
These materials are (1) excellent in repeated weather resistance,
It has the characteristics of (2) fast reaction of color fading and (3) high color density.

[0003]

However, when the above-mentioned photochromic material is used for sunglasses, since the glass is a heavy, prescription spectacle lens, the transmittance at the time of coloration is reduced by the thickness of the lens. Therefore, a problem has been pointed out that color unevenness (a dark color in a thick portion) occurs due to a lens portion.

On the other hand, with the spread of plastic in recent years,
Organic dimming materials such as spironaphthooxazine suitable for polymeric eyeglass materials have been developed. In order to form the organic light modulating material as a lens, (a) melt kneading with a thermoplastic plastic; (b) dissolving in a heat or photocurable resin monomer and polymerizing and casting; And (d) applying an organic light modulating material to a plastic molded product by immersion in a solvent or diffusion at a high temperature.

[0005] Among them, in the case of diethylene glycol diallyl carbonate, which is the most frequently used plastic lens, it is most effective to use a high-temperature diffusion method called an in-vibe method as shown in US Pat. No. 4,286,957. However, the thermoplastic resin such as polycarbonate or fluorene-based polyester resin cannot use the in-vivo method. Therefore, it is necessary to provide a polymer layer containing an organic light modulating material on the thermoplastic resin or on a part of the laminate layer. The properties required as a material for forming such a polymer layer are (1), (2) and (3) described above. However, the fact is that none of the currently available materials completely satisfy these properties. In addition, the above-mentioned U.S. Pat.
The resin disclosed in Japanese Patent No. 957 is a material suitable for spectacle lenses because it has a high refractive index and is easy to mold. However, when an organic light modulating material is used, the reason is not clear, but the color fades. Is slow and the color density is low.

As a resin satisfying the above-mentioned required properties (1), (2) and (3), all aliphatic polyurethane is known. However, in order to improve heat resistance, a high molecular weight (solution viscosity) is required. Need to be high). For this reason, when molding by the method (c) (a method of casting a film on a lens), there has been a problem that moldability is deteriorated and molding becomes difficult.

The present invention has been made in view of the above-mentioned circumstances, and has excellent repeated weather resistance, quick reaction of discoloration, high color density, and can be easily cast and laminated. Another object of the present invention is to provide a polyester polymer suitable for supporting an organic light modulating material and a molded product thereof.

[0008]

In order to achieve the above object, the polyester polymer of the present invention has the following constitution. That is, it is characterized by comprising a long-chain aliphatic compound having an alcoholic hydroxyl group at each end, or a carboxylic acid and an ester-forming derivative thereof, a dicarboxylic acid or an ester-forming derivative thereof, and a dihydroxy compound. .

The molded article of the present invention is a molded article molded from the above polyester polymer.

The long-chain aliphatic compound in the polyester polymer of the present invention preferably contains a compound represented by the general formula (1).

Embedded image (The relationship between n and X is 10 <(n + 1) X <300.)

The dicarboxylic acid in the polyester polymer of the present invention preferably contains an alicyclic dicarboxylic acid.
Cyclohexanedicarboxylic acid, decalindicarboxylic acid,
At least one compound selected from norbornanedicarboxylic acid, adamantanedicarboxylic acid and tricyclodecenedicarboxylic acid can be suitably used.

Further, as the dicarboxylic acid in the polyester polymer of the present invention, those containing terephthalic acid, isophthalic acid or an ester-forming derivative thereof are also suitable.

Further, the dihydroxy compound in the polyester polymer of the present invention is represented by the general formula (2):
9-bis [4- (2-hydroxyethoxy) phenyl]
Preferred is fluorene and its analogs.

Embedded image (R1 is an alkylene group having 2 to 4 carbon atoms, R2, R3,
R4 and R5 are hydrogen or an alkyl group having 1 to 4 carbon atoms, an aryl group, or an aralkyl group, which may be the same or different. )

The molded article of the present invention can be a light control lens or a light control sheet in which a dye having light control properties is dispersed in the polyester polymer described above, or a lens including these as a part of components. As this dye, spironaphthoxazine or spiropyrans can be suitably used.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The polyester polymer of the present invention comprises
It is obtained by copolymerizing a polyester with a long-chain aliphatic compound having an alcoholic hydroxyl group or a carboxylic acid and its ester-forming derivative at both ends. That is, it is characterized in that the partial chain of the long-chain aliphatic compound is copolymerized in the polyester, and the presence of the partial chain of the long-chain aliphatic compound in the polyester causes local molecular motion. It is possible to introduce a bulky and highly flexible component that facilitates, and as a result,
While maintaining the glass transition temperature within the practical range, coloring of the dye,
The decoloring reaction can be accelerated.

As the long-chain aliphatic compound having an alcoholic hydroxyl group or a carboxylic acid and an ester-forming derivative thereof at both terminals, a polyolefin such as polyethylene or polypropylene having a functional group copolymerizable with a polyester at both ends. A molecule or a polymer having a functional group copolymerizable with a polyester at both ends of a polyether can be used. Examples of the functional group copolymerizable with the polyester herein include an alcoholic hydroxyl group, a carboxylic acid and an ester-forming derivative thereof, and isocyanate and amide.

The long-chain aliphatic compound having an alcoholic hydroxyl group or a carboxylic acid and an ester-forming derivative thereof at both terminals can be used alone or in a mixture. Or introduced into the polyester by reactive kneading after polymerization.

The long-chain aliphatic compound having an alcoholic hydroxyl group or a carboxylic acid and its ester-forming derivative at both ends is preferably used as a long-chain aliphatic compound having a functional group copolymerizable with a polyester at both ends of a polyether. Is a molecule. Among them, polyethers having alcoholic hydroxyl groups at both ends can be particularly preferably used. For example, polyethylene glycol, polypropylene glycol, polytetrahydrofuran and the like. In these long-chain aliphatic compounds, it is preferable to consider the molecular weight because the molecular weight affects the properties. That is, if the molecular weight is too high, phase separation, and phase separation and crystallization of long-chain fatty chains tend to occur, the resin may cause cloudiness, and conversely, if the molecular weight is too low, local This is because a sufficient free volume for facilitating dynamic molecular movement cannot be provided, and the light control performance may be reduced.

The polyether having alcoholic hydroxyl groups at both ends can be represented by the general formula (1).

Embedded image At this time, considering the molecular weight as described above, for example, the relationship between n and X is preferably 10 <(n + 1)) X <1
000, more preferably 10 <(n + 1) X <500,
More preferably, 10 <(n + 1) X <300.

In the polyester polymer of the present invention, it is preferable to consider the amount of a long-chain aliphatic compound having an alcoholic hydroxyl group or a carboxylic acid and an ester-forming derivative thereof at both terminals. That is, if this amount is too large, the heat resistance will be reduced, and if it is too small, the light control characteristics may be deteriorated. Therefore, the amount added
With the weight of the dicarboxylic acid component as 100, preferably 1
It is 0-300, more preferably 20-200, even more preferably 40-150.

The dicarboxylic acid in the polyester polymer of the present invention preferably contains an alicyclic dicarboxylic acid. As alicyclic dicarboxylic acids, monocyclic alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid, decalin dicarboxylic acid, norbornane dicarboxylic acid, adamantane dicarboxylic acid, polycyclic alicyclic dicarboxylic acids such as tricyclodecene dicarboxylic acid, etc. Can be mentioned.

Examples of the ester-forming derivatives of these alicyclic dicarboxylic acids include the dicarboxylic acid ester-forming derivatives used in polyesters, such as alkyl esters such as dimethyl ester and diethyl ester. .

These alicyclic dicarboxylic acids or their ester-forming derivatives may be used alone or in combination of two or more as required. Among the alicyclic dicarboxylic acids, 2,6-decalin dicarboxylic acid is preferred in terms of ease of synthesis, moldability, optical properties, and the like.

The alicyclic dicarboxylic acid or its ester-forming derivative used in the present invention can be arbitrarily contained in an amount of 1 to 99 mol% with respect to the total amount of the dicarboxylic acid component as 100. The composition ratio varies depending on the intended resin and application, but is preferably in the range of 20 to 100 mol%, more preferably in the range of 30 to 100 mol%,
More preferably, it can be used in the range of 50 to 100 mol%. In order to further increase the heat resistance, it is preferable to use together with a polycyclic aromatic dicarboxylic acid or biphenyldicarboxylic acid.

The dicarboxylic acids used in the present invention include monocyclic aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, and the like. Polycyclic aromatic dicarboxylic acids such as aliphatic dicarboxylic acids such as methylmalonic acid and ethylmalonic acid, naphthalenedicarboxylic acids such as 2,6-naphthalenedicarboxylic acid and 1,8-naphthalenedicarboxylic acid, anthracenedicarboxylic acids, and phenanthenedicarboxylic acids Acids and biphenyl dicarboxylic acids such as 2,2'-biphenyl dicarboxylic acid can be exemplified.

In the present invention, examples of the dihydroxy compound represented by the general formula (2) include 9,9-bis [4- (2-hydroxyethoxy) phenyl] fluorene and 9,9-bis [4- ( 2-hydroxyethoxy)
-3-methylphenyl] fluorene, 9,9-bis [4
-(2-hydroxyethoxy) -3,5-dimethylphenyl] fluorene, 9,9-bis [4- (2-hydroxyethoxy) -3-ethylphenyl] fluorene, 9,
9-bis [4- (2-hydroxyethoxy) -3,5-
Diethylphenyl] fluorene, 9,9-bis [4-
(2-hydroxyethoxy) -3-propylphenyl]
Fluorene, 9,9-bis [4- (2-hydroxyethoxy) -3,5-dipropylphenyl] fluorene,
9,9-bis [4- (2-hydroxyethoxy) -3-
Isopropylphenyl] fluorene, 9,9-bis [4
-(2-hydroxyethoxy) -3,5-diisopropylphenyl] fluorene, 9,9-bis [4- (2-hydroxyethoxy) -3-n-butylphenyl] fluorene, 9,9-bis [4- ( 2-hydroxyethoxy)
-3,5-di-n-butylphenyl] fluorene, 9,
9-bis [4- (2-hydroxyethoxy) -3-isobutylphenyl] fluorene, 9,9-bis [4- (2
-Hydroxyethoxy) -3,5-diisobutylphenyl] fluorene, 9,9-bis [4- (2-hydroxyethoxy) -3- (1-methylpropyl) phenyl] fluorene, 9,9-bis [4- ( 2-hydroxyethoxy) -3,5-bis (1-methylpropyl) phenyl]
Fluorene, 9,9-bis [4- (2-hydroxyethoxy) -3-phenylphenyl] fluorene, 9,9-
Bis [4- (2-hydroxyethoxy) -3,5-diphenylphenyl] fluorene, 9,9-bis [4- (2
-Hydroxyethoxy) -3-benzylphenyl] fluorene, 9,9-bis [4- (2-hydroxyethoxy) -3,5-dibenzylphenyl] fluorene, 9,
9-bis [4- (3-hydroxypropoxy) phenyl] fluorene 9,9-bis [4- (4-hydroxybutoxy) phenyl] fluorene and the like can be mentioned. These may be used alone or in combination of two or more. Among these, 9,9-bis [4- (2-hydroxyethoxy) phenyl] fluorene can be preferably used because of its excellent optical properties and moldability. .

The above 9,9-bis [4- (2-hydroxyethoxy) phenyl] fluorene is, for example, 9,9-bis [4- (2-hydroxyethoxy) phenyl] fluorene.
It can be obtained by adding ethylene oxide (hereinafter abbreviated as EO) to bis (4-hydroxyphenyl) fluorene. At this time, a 2EO adduct (9,9-bis [4- (2
-Hydroxyethoxy) phenyl] fluorene), a 3EO adduct further added in a few molecular excess, 4EO
Impurities such as adducts may be included. Therefore, in order to increase the heat resistance of the polyester polymer as much as possible,
The purity of the 2EO adduct is preferably at least 85%, more preferably at least 95%.

In order to produce the polyester polymer of the present invention by a transesterification method of a melt polymerization method, it is preferable that the above-mentioned dihydroxy compound is contained within the range of 10 to 95 mol% of the glycol component in the resin. . That is,
When the content is 95 mol% or less, the melt polymerization reaction easily proceeds, and the polymerization time can be shortened. When the content is more than 95 mol%, polymerization can be performed in a short time by producing the solution by a solution polymerization method or an interfacial polymerization method. Further, by setting the content of the dihydroxy compound to 10 mol% or more, the glass transition temperature of the resin can be increased.

As the dihydroxy compound used in the present invention, besides those represented by the above general formula (2), there can be mentioned those usually used for plastics.
For example, ethylene glycol, 1,3-propanediol, 1,2-propanediol, 1,4-butanediol, 1,2-butanediol, 1,3-butanediol, 1,5-pentanediol, 1,4 -Aliphatic glycols such as pentanediol and 1,3-pentanediol; alicyclic glycols such as cyclohexane dimethanol and cyclopentane dimethanol; 1,4-benzene dimethanol and 1,3-benzene dimethanol. Aromatic diols and the like can be mentioned. Among them, ethylene glycol and 1,4-butanediol are preferable, and ethylene glycol is particularly preferable from the viewpoint of heat resistance. Also,
These may be used alone or in combination of two or more.

Further, if necessary, 1,1-bis [4-
(2-Hydroxyethoxy) phenyl] -1-phenylethane and other dihydroxy compounds having an aromatic ring in the main chain and side chain; bis [4- (2-hydroxyethoxy) phenyl] sulfone and other main chains having an aromatic ring and sulfur Or at least one or more other dihydroxy compounds may be used in combination with a limit of 10 mol% of the total diol component.

The polyester polymer of the present invention is, for example,
It can be manufactured by selecting an appropriate method from known methods such as a melt polymerization method such as a transesterification method and a direct polymerization method, a solution polymerization method, and an interfacial polymerization method. In addition, reaction conditions such as a polymerization catalyst at that time can be appropriately selected and determined.

In producing the polyester polymer of the present invention, when a solution polymerization method, an interfacial polymerization method, or the like is employed, generally, acid chloride is used as an active species of an acid component, or methylene chloride, chloroform, or the like is used as a solvent. Or use it. As a result, chlorides and catalyst compounds, which are by-products, remain in the polymer, but these are generally preferable to be removed in terms of product quality. Is preferred. That is, this residual foreign matter is a sheet, a film, a plate,
There is a possibility that the operability in the molding step of fibers or the like is reduced, and the quality of the obtained molded body is also reduced. For example, a large amount of thermal decomposition may occur during heating at a high temperature. In addition, when used as an optical material, a metal thin film such as a reflective film or a recording film is fixed to a plate or a substrate by a method such as vapor deposition or sputtering. Corrosion and shorten the life and reliability of the product. Therefore, it is preferable to provide a residual foreign matter removing step such as a sufficient washing step and a filtering step.

In producing the polyester polymer of the present invention, it is preferable to apply a melt polymerization method. That is, the compound of 9,9-bis [4- (2-hydroxyethoxy) phenyl] fluorene has an advantage that the terminal group has a property similar to that of the aliphatic glycol and that the reactivity is high. I have. This is the 9,9-bis (4
-Hydroxyphenyl) fluorene. For this reason, there is no need to use a raw material such as acid chloride, and therefore, there is substantially no contamination of chlorine, and the amount of catalyst used can be reduced under high-temperature reaction conditions. It can be realized.

The polyester polymer of the present invention may contain an appropriate amount of a lubricant, a heat-resistant agent, an antistatic agent, an ultraviolet absorber, a pigment and the like depending on the purpose of molding. Further, when providing the polyester polymer of the present invention to an optical material,
In addition to the raw material charging step, the polymerization step, the step of pelletizing the polymer, the step of injection molding or the step of molding into a sheet or film, etc. You can get things.

Since the polyester polymer of the present invention is amorphous, it is extremely excellent in transparency. In addition, because it has excellent melt viscoelastic properties, it is excellent in moldability, and it is difficult for residual stress strain and molecular orientation to occur during molding, and even if they remain, optical anisotropy is very small Has characteristics. Therefore, the polyester polymer of the present invention can be used very effectively as a transparent material or an optical material.

The molded article of the present invention is obtained by molding the polyester polymer of the present invention, and includes a known molding method such as an injection molding method, an injection compression molding method, and a transfer molding method. A method such as a blow molding method, an extrusion molding method, a pressure molding method, and a casting molding method can be applied.

In molding a lens as the molded article of the present invention, a suitable molding method may be selected from the above-mentioned molding methods. For example, when a layer containing a light control agent as a dye having light control properties is formed on a lens, the light control agent and the resin are dissolved in an appropriate solvent in advance, and then spin-cast on the lens, dipping, or the like. Unfold the solution,
After drying it, a method of removing the solvent can be adopted. When the dipping method is used, the layer can be formed by dissolving the light control agent and the resin in an appropriate solvent, immersing the lens therein and pulling up the lens at an appropriate speed.

When a layer comprising the polyester polymer of the present invention is provided between thin lenses, injection molding, injection compression molding, transfer molding, blow molding, extrusion molding, pressure molding, etc. It is possible to adopt a method in which a film containing a light control agent is prepared by a method or the like, and the film is attached between two lenses using an appropriate adhesive.

As the dye having light control properties used in the molded article of the present invention, it is preferable to use spironaphthoxazine or spiropyran. For example, the Society of Chemistry Publishing Center, “The Chemistry of Organic Photochromism” (1996 N
Compounds described in o28) can be used.

[0040]

The present invention will be described below in detail with reference to examples. The glass transition temperature and light control properties of the polymer were measured by the following methods.

1. Glass transition temperature About 10 mg of a sample was measured using a differential scanning calorimeter (Rigaku Denki DSC-8230) at a heating rate of 10 ° C./min. The glass transition temperature Tg was determined according to JIS K7121-1987.

2. Light control properties For coloring the photochromic film, a 100 W high-pressure mercury lamp equipped with a cut filter of 300 nm or less was used. The absorbance was measured using a spectrophotometer UV-2400PC manufactured by Shimadzu Corporation. The change in absorbance when the photochromic film was colored by the colored light source was measured, and the change in absorbance was measured when the color was erased by leaving it in a dark place. did.

Example 1 50 g of 2,6-decalin dicarboxylic acid dimethyl ester
(0.2 mol), 35 g of 9,9-bis [4- (2-hydroxyethoxy) phenyl] fluorene (0.
08 mol), 27.3 g (0.44 ethylene glycol)
Mol) as a raw material, 50 g of polytetrahydrofuran having an average molecular weight of 1,000, and 28 m of calcium acetate as a catalyst.
g and 10 mg of manganese acetate, and these were charged into a reaction vessel, and stirred at 190 ° C. to 245 ° C. according to a conventional method.
The mixture was gradually heated to perform a transesterification reaction. After extracting a predetermined amount of methanol out of the system, 0.012 mol of germanium oxide, which is a polymerization catalyst, and to prevent coloring,
With the addition of 0.0018 mol of phosphoric acid trimethyl ester, the temperature is gradually increased and reduced, and the temperature of the heating tank is set to 280 ° C. and the degree of vacuum is set to 1 while removing generated ethylene glycol.
Torr or less. Maintain this condition, wait for the viscosity to rise, and after reaching the predetermined stirring torque (after about 2 hours)
The reaction was terminated, and the reaction product was extruded into water to obtain a pellet.

Examples 2 to 7 and Comparative Examples 1 to 5 Pellets were produced in the same manner as in Example 1 except that the raw material composition ratios were changed as shown in Table 1, and evaluated similarly. Table 1 shows the evaluation results.

[0045]

[Table 1]

As is evident from Table 1, all of the polyester polymers of the examples are uniform and transparent without cloudiness. In addition, when the amount of polytetrahydrofuran was too large, as in Comparative Example 3, no cloudiness occurred, but it was confirmed that the glass transition temperature was low and the heat resistance was poor.

Example 8 The pellets obtained in Example 1 were dried under reduced pressure and dissolved in a mixed solvent of toluene / 2-butanone = 4/6 so that the polymer concentration became 23%. In 10 g of this polymer solution, 0.046 g of a photochromic dye Sea Green manufactured by James-Robinson was dissolved.
A polymer / dye solution was prepared. Using this solution, a photochromic film was formed on a polyethylene terephthalate substrate by spin casting. The light control properties of these films were measured.

Comparative Examples 6 to 8 All aliphatic polyurethanes were prepared as Comparative Example 6, resins not using polytetrahydrofuran in Example 1 as Comparative Example 7, and polystyrene as a typical binder as Comparative Example 8 were prepared. Optical properties were measured. The results are shown in FIGS. FIG. 1 shows a color reaction and FIG. 2 shows a decolorization reaction. The absorbance is converted per micrometer of the film, and the relative intensity is represented by a value obtained by dividing by the maximum value of the absorbance.

[0049]

As described above, the polyester polymer of the present invention is excellent in repeated weather resistance, has a fast reaction of discoloration and a high coloration density, and can be easily cast and laminated. It is. Further, the molded article of the present invention is a very useful one having all the characteristics required as a transparent material and an optical material.

[Brief description of the drawings]

FIG. 1 is a diagram showing measurement results of dimming characteristics of Example 1 and Comparative Examples 6 to 8, showing a color reaction.

FIG. 2 is a diagram showing measurement results of dimming characteristics of Example 1 and Comparative Examples 6 to 8, and shows a decoloring reaction.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) G03C 1/00 531 G03C 1/00 531 F term (Reference) 2H006 BE02 2H123 AA12 AA19 BA16 EA15 4J002 CF031 CF041 CF051 CF101 FD096 GP01 4J029 AA03 AB01 AC02 AD01 AE04 BA02 BA03 BA04 BA05 BA08 BB06A BB12A BB12B BD06A BF25 CA02 CA03 CA04 CA05 CA06 CB05A CB06A CC05A CC06A CD03 HA01 HB01 HB03A JD05 JE182

Claims (9)

[Claims] 1. A long-chain aliphatic compound having an alcoholic hydroxyl group or a carboxylic acid and an ester-forming derivative thereof at both terminals, a dicarboxylic acid or an ester-forming derivative thereof, and a dihydroxy compound. Polyester polymer. 2. A polyester polymer, wherein the long-chain aliphatic compound according to claim 1 contains a compound represented by the general formula (1). Embedded image (The relationship between n and X is 10 <(n + 1) X <300.) 3. The polyester polymer according to claim 1, wherein the dicarboxylic acid contains an alicyclic dicarboxylic acid. 4. The alicyclic dicarboxylic acid according to claim 3,
Cyclohexanedicarboxylic acid, decalindicarboxylic acid,
A polyester polymer which is at least one compound selected from norbornanedicarboxylic acid, adamantanedicarboxylic acid and tricyclodecenedicarboxylic acid. 5. The polyester polymer according to claim 1, wherein the dicarboxylic acid comprises terephthalic acid or isophthalic acid or an ester-forming derivative thereof. 6. The method according to claim 1, wherein the dihydroxy compound is 9,9-bis [4- (2-hydroxyethoxy) phenyl] fluorene represented by the general formula (2) and an analog thereof. Polyester polymer. Embedded image (R1 is an alkylene group having 2 to 4 carbon atoms, R2, R3,
R4 and R5 are hydrogen or an alkyl group having 1 to 4 carbon atoms, an aryl group, or an aralkyl group, which may be the same or different. ) 7. A molded article molded from the polyester polymer according to any one of claims 1 to 6. 8. The molded article according to claim 7, wherein the molded article is
A light-modulating lens, a light-modulating sheet, or a molded article that is a lens including these as a part of components, in which a dye having light-modulating properties is dispersed in the polyester polymer according to any one of the above. 9. A molded article wherein the dye according to claim 8 is spironaphthoxazine or spiropyran.