JP2003026836A - Blow molded polyester article, method for recycling of the article and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a blow molded article made of PEN, free from the contamination of the contents, keeping high transparency even after repeated reuse and reusable in a state essentially free from the scratch on the surface. SOLUTION: The blow molded article made of the polyester has a coating layer of a polyester (A) on the outer surface. The coating layer contains organic particles (B) having an average particle diameter of 20-2,000 nm in an amount of 5-20 wt.% based on the polyester (A). The layer is removable with hot water of 70-100 deg.C or with an alkaline aqueous solution of pH 10 or above and has a surface friction resistance of 0.1-0.4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hollow polyester product, a method for regenerating the hollow product, and a method for producing the hollow product.

[0002]

2. Description of the Related Art Polyethylene naphthalene dicarboxylate (hereinafter sometimes abbreviated as PEN) type hollow molded articles have superior properties to polyethylene terephthalate (hereinafter sometimes referred to as PET) type hollow molded articles. It is expected to be a hollow molded product that has the following properties and can be recovered and reused.

[0003] The reuse of the hollow molded body is required for reuse, and the cleaning is usually performed using a sodium hydroxide aqueous solution (1 to 6%) at 50 to 100 ° C.

However, when the PEN-based hollow molded article recovered after use is subjected to alkali cleaning, the transparency of the hollow molded article is reduced. Then, the degree of decrease in transparency becomes more remarkable as the number of times of recycling such as recovery and reuse increases.

[0005]

In order to suppress the decrease in transparency, it is effective to coat the surface of the PEN hollow molding with a water resistant material. However, even if the surface of the PEN-based hollow molded article is simply coated, it has water resistance, but it is difficult to remove the coating layer when it is reused. For example, it cannot be removed by washing with hot water.

Further, if an ultraviolet absorbing compound is blended with the material of the hollow molded article without providing a coating layer, there is a concern of contaminating the contents by bleeding out.

Further, the surface of the PEN-based hollow molded article is easily scratched, and it is necessary to suppress the occurrence of scratches on the surface for recovery and reuse.

The present invention has no fear of contamination of the contents, maintains good transparency even when recovered and reused, and can be reused in a state where the surface is substantially free of scratches and can be reused. The challenge is to provide the body.

The inventor has arrived at the present invention by finding out the following. That is, the surface of the PEN-based hollow molded article is deteriorated by ultraviolet rays during distribution in the market and during storage after recovery, and the deteriorated portion is easily peeled off by washing with an alkaline aqueous solution, and the hollow molded article is The hollow molded bodies are easily damaged by the contact between the hollow molded bodies in the process of reusing. This deterioration,
The inventors of the present invention have found that peeling and scratching become more remarkable as the number of times of collecting and reusing the hollow molded body increases, and the transparency is significantly lowered, and thus the present invention was achieved.

[0010]

Means for Solving the Problems That is, the present invention is a polyester hollow molded article having a polyester (A) coat layer on its outer surface, the coat layer having an average particle size of 20 to
The organic particles (B) of 2000 nm are contained in an amount of 5 to 20% by weight based on the weight of the polyester (A), and can be removed with hot water at 70 to 100 ° C. or an alkaline aqueous solution having a pH of 10 or more, and the surface friction resistance is It is a hollow product made from polyester characterized by being 0.1-0.4.
Hereinafter, the present invention will be described in detail.

[Coat layer of polyester (A)] The present invention is the above-mentioned polyester hollow molded article, which comprises a polyester hollow molded article body and a polyester (A) formed on the outer surface thereof. And a coat layer. And the coat layer made of polyester (A) is
It contains organic particles (B).

The polyester (A) coat layer has a thickness of 60-
It can be removed with hot water of 100 ° C. or an alkaline aqueous solution of pH 10-14. The pH of hot water is 5.5 to 8.
5, preferably 6-8. The alkaline aqueous solution preferably has a pH of 10 to 13, and the temperature is preferably 7
It is 0 to 95 ° C. When the coat layer satisfies this condition,
In the washing step, the coat layer on the outer surface can be easily removed from the hollow polyester body.

It is desirable that the polyester (A) coat layer cannot be completely removed with water at 35 ° C. or lower. This is because the reduction rate of the coating layer when immersed in water having a pH of 6 to 8 at 35 ° C. or lower for 10 minutes is 0 by weight.
~ 20%, preferably 0-10%,
Alternatively, it means that the thickness is 0 to 20%. If this condition is satisfied, the polyester hollow molded article is distributed and used in the market as a container, and even if it may come into contact with water during this period, the coat layer is substantially retained. If the reduction rate exceeds this range and the reduction rate is large, the coat layer is substantially peeled off or peeled off, which causes a problem in appearance.

In order to make the coat layer satisfy the above conditions, it is preferable to use the following polyester (A) as the coat layer.

The surface-coating polyester (A) comprises at least one unit selected from the group consisting of naphthalenedicarboxylic acid units, terephthalic acid units and isophthalic acid units per 93 parts of total dicarboxylic acid components. Isophthalic acid units having 60 mol% and a metal sulfonate group of 7 to 7 per total dicarboxylic acid component
It is a polyester composed of a dicarboxylic acid component composed of 40 mol% and a diol component composed of an aliphatic diol.

As the naphthalene dicarboxylic acid unit,
Examples are 2,6-naphthalenedicarboxylic acid and 2,7-naphthalenedicarboxylic acid, with 2,6-naphthalenedicarboxylic acid being preferred.

The naphthalenedicarboxylic acid unit, the terephthalic acid unit and the isophthalic acid unit may be derived from an ester derivative. Examples of the ester derivative include methyl ester, ethyl ester, propyl ester and butyl ester, and among them, methyl ester is preferable.

At least one unit selected from the group consisting of naphthalenedicarboxylic acid units, terephthalic acid and isophthalic acid units is preferably 93 to 60 mol% based on the total dicarboxylic acid component. When it is less than 60 mol%, the water resistance of the polyester is lowered, and when it exceeds 93 mol%, the hot water solubility is lowered, which is not preferable. From the viewpoint of hot water solubility, the naphthalenedicarboxylic acid unit is more preferably 50 mol% or less of the total dicarboxylic acid component.

The naphthalenedicarboxylic acid unit is preferably 0 to 50 mol%, more preferably 0 to 50 mol% based on the total dicarboxylic acid component in order to obtain particularly good hot water solubility.
It is 30 mol%, particularly preferably 0 to 10 mol%.

Examples of the isophthalic acid unit having a metal sulfonate group include 5-lithium sulfoisophthalic acid and 5-lithium sulfoisophthalic acid.
Examples include sodium sulfoisophthalic acid and 5-potassium sulfoisophthalic acid, and among them, 5-sodium sulfoisophthalic acid is preferable.

These may be derived from derivatives. The derivative is, for example, an ester, and examples thereof include methyl ester, ethyl ester, propyl ester, and butyl ester, with methyl ester being preferred.

The polyester (A) preferably contains, as a diol component, an aliphatic diol represented by the following formula in an amount of 80 mol% or more based on all diol units.

[0023]

[Chemical 1] (However, n is an integer of 2 to 6)

The isophthalic acid unit having a metal sulfonate group is preferably in the range of 7 to 40 mol% based on the total dicarboxylic acid component. If it is less than 7 mol%, the hot water solubility is insufficient, and if it exceeds 40 mol%, the foaming during polymerization is large, and the thickening due to the reaction is large, only the melt viscosity becomes high, and the degree of polymerization is suppressed to be low. , Not preferable. Here, when n in the aliphatic diol of the formula (1) is 2, the isophthalic acid unit having a metal sulfonate group is
The range of 7 to 15 mol% is more preferable, and when n is 3 to 6, the range of 20 to 40 mol% is more preferable.

The intrinsic viscosity of polyester (A) is
Preferably 0.2 to 0.5, more preferably 0.25 to
It is 0.45. If the intrinsic viscosity is less than 0.2, it is difficult to form chips during polymerization, and the strength is low, which is not preferable.
If it exceeds 0.5, productivity during polymerization is poor and hot water solubility is poor, which is not preferable.

The polyester (A) can be produced by the method exemplified below. For example, terephthalic acid or its ester-forming derivative (preferably dimethyl ester), isophthalic acid or its ester-forming derivative (preferably dimethyl ester), 2,6-naphthalenedicarboxylic acid or its ester-forming derivative (preferably). , Dimethyl ester), isophthalic acid having a sulfonic acid metal base or its ester-forming derivative (preferably dimethyl ester), ethylene glycol, propylene glycol and butylene glycol. , One or more kinds of aliphatic diols selected from hexamethylene glycol and, if necessary, other diols are esterified or transesterified under heating.

In the case of transesterification reaction, as catalysts, cobalt, manganese, calcium, magnesium and / or
Alternatively, a titanium compound may be used. An alkali metal may be added to control the reactivity and the diethylene glycol content. As the alkali metal, lithium, sodium and potassium are preferable, and sodium is particularly preferable. The addition amount is preferably 10 to 400 mmol%, more preferably 100 to 250 mmol%, based on the total dicarboxylic acid component.

Subsequently, the polycondensation reaction is carried out under heating vacuum in the presence of the germanium, antimony and / or titanium catalyst and the phosphorus compound. As the phosphorus compound, inorganic phosphoric acid such as orthophosphoric acid, hypophosphorous acid and phosphorous acid, and organic phosphoric acid such as trimethyl phosphate are preferably used. Then, if desired, the polymer is used in the form of chips or pellets, or in the form of blocks to be ground.

The coating layer can be formed by applying the polyester (A) as a liquid coating liquid to at least the outer surface of the main body of the hollow polyester body and drying. Liquid coating liquid is polyester (A)
Is preferably contained in an amount of 1 to 40% by weight based on the total weight of the coating liquid.

The coat layer has an average particle size of 20 to 2000 nm.
5 to 20% by weight of the organic particles (B) of (1) based on the weight of the polyester (A). The average particle diameter of the organic particles (B) is more preferably 20 to 400 nm, and 30 to 100 nm.
nm is particularly preferred. The average particle size of the organic particles (B) is 20
If it is smaller than nm, the effect of reducing the surface friction resistance is low, and 2
If it is larger than 000 nm, the transparency is greatly lowered, which is not preferable.

The content of the organic particles (B) in the coating layer is
It is 5 to 20% by weight based on the weight of the polyester (A). Content of inorganic particles in the coat layer is polyester (A)
On the other hand, if it is less than 5% by weight, the effect of reducing the surface friction resistance is low, and if it exceeds 20% by weight, the coat layer becomes brittle or the transparency is lowered, which is not preferable.

The organic particles (B) are preferably inert particles, and include crosslinked silicone resin, crosslinked polystyrene, crosslinked acrylic resin, melamine-formaldehyde resin, aromatic polyamide resin, polyimide resin, polyamide resin, crosslinked polyester resin. , Etc. can be illustrated.
Among them, crosslinked silicone resin, crosslinked polystyrene and crosslinked acrylic resin are preferable.

The coating layer of the polyester (A) containing the organic particles (B) as described above is formed on the outer surface of the polyester hollow molded article by coating.

As a coating method, for example, a spray, a dope, or the like can be applied. If necessary, a film may be formed, and forced drying or natural drying can be applied.

As a method of applying the liquid coating solution, a method of dissolving or dispersing the polyester (A) and the organic particles (B) in an organic solvent or water can be applied. As the organic solvent, ethanol, methanol,
Examples thereof include isopropyl alcohol, chloroform, acetone, methyl ethyl ketone and ethyl acetate. When the polyester (A) is dissolved or dispersed in water, it is preferable to use water heated to 60 to 100 ° C.

The liquid coating liquid may contain a surfactant. By containing a surfactant, when the hollow molded body is coated, the wettability is improved, and
When the coat layer is removed, it can be efficiently removed using hot water or an alkaline aqueous solution.

Examples of the surfactant include polyethylene glycol and polyoxyethylene sorbitan alkylate. You may use together several types of surfactants.
The amount of the surfactant added is preferably 0.1 to 5% by weight of the coating liquid, more preferably 0.1 to 3% by weight.

The polyethylene glycol is preferably a liquid low viscosity one having a molecular weight of 200 to 1,000, and the polyoxyethylene sorbitan alkylate is polyoxyethylene sorbitan oleate or polyoxyethylene sorbitan stearate. , Polyoxyethylene sorbitan palmitate is exemplified, and polyoxyethylene sorbitan oleate is particularly preferred.

This coating layer has the effect of preventing the occurrence of scratches on the outer surface of the hollow molded article, filling in minute scratches, and preventing the appearance from being impaired. Furthermore, it has the ability to absorb ultraviolet rays,
When used, collected and stored, it has an effect of suppressing deterioration of the polyethylene naphthalene dicarboxylate of the polyester hollow molded article by ultraviolet rays.

The polyester hollow molded article of the present invention having this coat layer has a haze of preferably 10% in its body.
Or less, more preferably 5% or less. Haze is 10
% Is not preferable because the transparency is low and the appearance of the product as a product is deteriorated when the polyester hollow molding is used as a bottle for filling a beverage or the like.

The thickness of the coat layer is preferably 0.1 to 1
The thickness is 0 μm, more preferably 0.1 to 5 μm, and further preferably 0.2 to 2 μm. If it is less than 0.1 μm, the effect of suppressing photodegradation and scratches by coating the surface of the hollow molded article is low, which is not preferable, and if it exceeds 10 μm, it takes a long time to remove the coat layer with hot water or an alkaline aqueous solution, which is not preferable. .

In the present invention, the surface friction resistance of the coating layer is 0.1 to 0.4, preferably 0.2 to 0.4, more preferably 0.25 to 0.38. When the surface frictional resistance is higher than 0.4, the slipperiness of the surface is poor and the surface of the hollow molded article is greatly scratched, and when it is lower than 0.2, it tends to slip off when gripped by hand.

Therefore, the polyester hollow molded article of the present invention, provided with the coat layer, is 0.1 to 0.4, preferably 0.2 to 0.4, and more preferably 0.25.
It has a surface frictional resistance of 0.38.

In the present invention, the coat layer is 70-100.
It can be removed with hot water at ℃ or an alkaline aqueous solution having a pH of 10 or more.

[Polyester Hollow Molded Body] The polyester hollow molded body of the present invention comprises a polyester hollow molded body and a polyester (A) coat layer formed on the outer surface of the polyester hollow molded body. The molded body contains ethylene-2,6-naphthalenedicarboxylate units in an amount of preferably 5% by weight or more, more preferably 10% by weight or more, further preferably 50% by weight or more, and particularly preferably 85% by weight or more. The thermoplastic polyester is contained as a repeating unit of.

The thermoplastic polyester ethylene-2,6
The naphthalene dicarboxylate unit may be present in the thermoplastic polyester as a constituent component of the copolyester, and as a constituent component of the polymer used as a constituent component of the polymer forming the mixture (blend) of the polyester. May exist. That is, the thermoplastic polyester includes ethylene terephthalate units and ethylene-
It may be a copolyester composed of 2,6-naphthalenedicarboxylate units, or may be a mixture of polyethylene terephthalate and polyethylene-2,6-naphthalenedicarboxylate.

The intrinsic viscosity of the thermoplastic polyester is preferably 0.5 to 1.0, more preferably 0.55 to 0.
8, particularly preferably 0.55 to 0.75. When the intrinsic viscosity is less than 0.5, the blowability is poor and it is difficult to obtain a molded product having a uniform wall thickness, and when it exceeds 1.0, the stretching stress is high, which may cause haze, which is not preferable. .

The polyester hollow molded article body made of this thermoplastic polyester can be manufactured by applying a generally known ordinary molding method. Examples of applicable molding methods include a biaxial stretching blow method (cold parison method, hot parison method), an injection blow method, and a direct blow method. In addition, a molding method may be applied in which a thermoplastic polyester is formed into a sheet-shaped molded product and then processed into a hollow molded body.
The thermoplastic polyester hollow molding may be a bottle.

In the present invention, this coating layer is removed each time the polyester hollow molded article is repeatedly used,
Updated by playing.

Therefore, the present invention also relates to a method for regenerating a polyester hollow molded article in which the coat layer is removed from the recovered polyester hollow molded article to form a coat layer again, wherein the polyester hollow molded article is the above-mentioned product. The method for remanufacturing a polyester hollow molded article is characterized in that it is a polyester hollow molded article.

In other words, this is a method for producing a polyester hollow molded article, which comprises a step of removing the coat layer from the recovered polyester hollow molded article and a step of forming a coat layer thereafter. A method for producing a polyester hollow molded article, wherein the polyester hollow molded article is the above-mentioned polyester hollow molded article.

The step of removing the coat layer is preferably a step including washing with warm water or an alkaline aqueous solution and subsequent washing with water.

The temperature of the water or the alkaline aqueous solution used for removing the coating layer in the washing with the heated water or the alkaline aqueous solution is preferably 70 to 100 ° C, more preferably 75 to 95 ° C. If it is lower than this, sufficient washing cannot be performed, the coat layer cannot be removed sufficiently, and further, a bactericidal effect cannot be expected, which is not preferable. If it is higher than this, thermal deformation of the hollow polyester body is caused, which is not preferable. If an alkaline aqueous solution is used, sodium hydroxide is preferably used at a concentration of 1-6%.

The washing with warm water or alkaline aqueous solution is preferably carried out by immersing the hollow polyester body in the warm water or alkaline aqueous solution described above. In some cases, the above-mentioned heated water or aqueous solution is added to a polyester hollow molded article,
A method of jetting may be used.

In washing with water after washing with warm water or an alkaline aqueous solution, water at 95 ° C. or lower is preferably used. This cleaning may be a cleaning that sufficiently flushes the alkaline aqueous solution.

In the present invention, the polyester hollow molded article is regenerated by forming a coat layer on the polyester hollow molded article from which the coat layer has been removed and renewing the coat layer. As the method for forming the coat layer at this time, the method for forming the coat layer used when manufacturing the polyester hollow molded article can be applied.

The coat layer is preferably renewed each time the hollow polyester product is repeatedly used. That is, a method for regenerating a polyester hollow molded article, in which the polyester hollow molded article is regenerated by the above-described regenerating method each time it is reused, is preferably applied.

The polyester hollow molded article can be repeatedly used by renewing the coat layer by this recycling method, and the haze of the body portion at the time of repeated use of 10 times is 10%.
Hereafter, it can be made 5% or less, more preferably.

[0059]

EXAMPLES The present invention will be described in more detail with reference to examples. The evaluation was performed by the following method.

(1) Preparation of test piece A 4 cm × 4 cm test piece was cut out from the bottle body (thickness: about 300 μm) together with the surface coating layer.

(2) A haze test piece was put on a turbidimeter (manufactured by Nippon Denshoku Industries Co., Ltd., Color and color).
The haze was measured by setting it on a diference meter, MODEL 1001DP).

(3) As a particle size sample of organic particles, a test piece cut out from a bottle of a hollow molded body was fixed on a sample stand for a scanning electron microscope, and a sputtering device (JFC-1100 type manufactured by JEOL Ltd.) was fixed. The surface of the bottle was subjected to an ion etching treatment using an ion etching apparatus). This ion edging process
Place the sample in a bell jar, raise the degree of vacuum to a vacuum state of about 10 ^-3 Torr, voltage 0.25 KV, current 12.
It was carried out by ion etching at 5 mA for about 5 minutes. Furthermore, gold spatter was applied to the bottle surface with the same sputtering device, and it was observed with a scanning electron microscope.
The observation was performed at 000 to 30,000 times, and the major axis (Dli), the minor axis (Dsi) and the area equivalent circle diameter (Di) of at least 100 particles were determined with Luzex 500 manufactured by Nippon Regulator Co., Ltd. Then, the average particle size was calculated from these values. Area circle equivalent (Di) = {major axis (Dli) x minor axis (Ds)
i)} ^0.5

(4) Evaluation of Surface Scratchability during Repeated Preparation of Coated Bottle After spraying the coating liquid on the bottle, it was dried by holding it in an oven at 100 ° C. for about 10 minutes to prepare a coated bottle. Evaluation of surface scratch resistance A coated bottle was filled with 900 g of water and sealed. These four bottles were placed in a box-shaped container (with polyethylene naphthalene dicarboxylate sheet; 300 μm affixed inside) attached to a shaker, with the bottles in contact with each other, and shaken for 5 minutes. Processed at a rate of times / minute. It was washed by immersing it in a 1.8% NaOH aqueous solution (pH 11.6) at 75 ° C. for 15 minutes by the bottle washing dipping method, further washing with water, and then drying. By repeating 6 times, the scratching property during repeated use was evaluated.

(5) Intrinsic Viscosity 180 mg of a crushed test piece was dissolved in a mixed solvent of phenol: tetrachloroethane = 3: 2 and measured with an Ubbelohde viscometer at 25 ° C.

(6) Surface friction resistance A test piece cut out from the bottle body was fixed on a plate. On the other hand, 260 g in weight, length x width x thickness = 5 cm x 8 c
The test piece was attached to the entire bottom surface of the m × 8 mm metal block with a tape. The metal block was placed on the plate, the plate was tilted, and the angle (θ) at which the metal block started to move was measured. The surface frictional resistance μ is calculated from the angle (θ) by the following formula. μ = tan θ

Reference Example 1 Production of Polyester (A) Polyester (A) was produced by the following method. 100 parts by weight of dimethyl terephthalate (hereinafter abbreviated as DMT), 19 parts by weight of dimethyl 5-sodium sulfoisophthalate (hereinafter abbreviated as K2), 12.5 parts by weight of dimethyl isophthalate (hereinafter abbreviated as DMI) 72 parts by weight of ethylene glycol (hereinafter abbreviated as EG) and manganese acetate and sodium acetate are used to distill off by-produced methanol to the outside of the system and carry out a transesterification reaction while heating up to 250 ° C., When the distillation of methanol was almost completed, antimony trioxide was added as a polymerization catalyst, and orthophosphoric acid was subsequently added as a stabilizer to terminate the transesterification reaction. The obtained reaction product was subjected to polycondensation reaction under high temperature and high vacuum to obtain a polymer having an intrinsic viscosity of 0.40.

This polymer comprises a naphthalene dicarboxylic acid (hereinafter abbreviated as NDC) component of 0 mol% based on all dicarboxylic acid components, a terephthalic acid component of 80 mol% based on all dicarboxylic acid components, and an isophthalic acid component of all dicarboxylic acid components. 10 mol% per 5% sodium sulfoisophthalic acid (isophthalic acid having a sulfonic acid metal salt group as a substituent) component, 10 mol% per total dicarboxylic acid component, and ethylene glycol component total diol The polyester was 90 mol% per component and 10 mol% of diethylene glycol component based on all diol components. A polyester (A) chip was obtained using this polymer as a strand type chip.

[Reference Examples 2 and 3] Reference Examples 2 and 3
Was manufactured by changing the ratio of DMT, DMI and K2 as shown in Table 1.

[0069]

[Table 1]

Reference Example 4 Production of Polyester (A) Polyester (A) was produced by the following method. 100 parts by weight of dimethyl terephthalate (hereinafter abbreviated as DMT), 76 parts by weight of dimethyl 5-sodium sulfoisophthalate (hereinafter abbreviated as K2), 16 parts by weight of dimethyl isophthalate (hereinafter abbreviated as DMI) and hexamethylene 112 parts by weight of glycol (hereinafter abbreviated as HMG) was used to distill off the by-produced methanol out of the system using tetrabutoxytitanate and to conduct an ester exchange reaction while heating up to 220 ° C. to distill off methanol. The polycondensation reaction was carried out under high temperature and high vacuum on the reaction product obtained at the stage when the reaction was almost completed to obtain a polymer having an intrinsic viscosity of 0.40.

This polymer had a terephthalic acid component of 60 mol% based on the total dicarboxylic acid component, an isophthalic acid component of 10 mol% based on the total dicarboxylic acid component, and 5-sodium sulfoisophthalic acid (with the group of the sulfonic acid metal salt as a substituent group). It was a polyester having an isophthalic acid) component as a dicarboxylic acid component of 30 mol% based on all dicarboxylic acid components. Using this polymer as a strand type chip, a polyester (A) chip shown in Table 1 was obtained.

[Reference Examples 5 to 10] Preparation of solutions for surface coating The polyester chips of Reference Examples 1 to 4 described above were dissolved in hot water at 95 ° C for 60 hours with stirring. The polyester concentration was 10% by weight. For these solutions, crosslinked acrylic resin (average particle size 40 nm), crosslinked silicone resin (400 nm) and polyethylene glycol (molecular weight 2
00), polyoxyethylene sorbitan alkylate was added to prepare coating solutions in Table 2.

[0073]

[Table 2]

[Reference Example 11] Preparation of hollow molded body (bottle) Polyethylene naphthalate resin (trademark: T manufactured by Teijin Limited)
Using EONEX resin, grade name: TN8065), a preform of a hollow molded body was injection-molded, and then this preform was heated and then orientation blown to mold a bottle.

The preform is M100DM manufactured by Meiki Seisakusho.
Molding with a molding machine (cylinder setting 295 ° C, screw
Rotation speed 160 rpm, molding cycle 30 sec), the average body thickness of the preform is 4.2 mm, and the weight is about 5
5 g, intrinsic viscosity (IV) was 0.62.

The bottle is LB0 manufactured by KRUPP CORPOPLAST.
Molded in 1, the bottle had an internal volume of about 1.5 L (liter), an average barrel thickness of about 300 μm, and a haze of 0.7%.

[Examples 1 to 6] A coating liquid having the composition shown in Table 2 was applied to the outer surface of the above-mentioned bottle to obtain 100 ° C x 10 ° C.
After drying in an oven for a minute, a surface coating layer having a thickness of about 2 μm was formed, and 9 bottles having the surface coating layer were prepared.

Using these test bottles, the surface scratch resistance was evaluated when (4) was repeated. As for the results, the bottle appearance (visual inspection) after the surface coating was evaluated, and a sample was cut out from a large scratched portion of the bottle shoulder, and the haze was measured. The results are shown in Table 3.

The surface coat layer of the bottle provided with the original surface coat layer was 30 ° C. (35 ° C. or lower) water (pH 6.
Although it could not be removed in 5), it could be completely removed in the above washing.

[0080]

[Table 3]

Comparative Example 1 The same evaluations as in Examples 1 to 5 were carried out without forming the coat layer on the outer layer of the bottle. The results are shown in Table 3.

[0082]

EFFECTS OF THE INVENTION According to the present invention, there is no fear of contamination of the contents, and good transparency is maintained even after repeated use by recovery and reuse, and the surface is reused with substantially no scratches. It is possible to provide a polyester hollow molded article that can be obtained.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) B65D 65/42 BRF B65D 65/42 BSFC BSF C08G 63/688 ZAB C08G 63/688 ZAB C08L 67:00 // C08L 67:00 B65D 1/00 B F term (reference) 3E033 AA01 BA18 BA30 BB08 CA20 FA03 GA02 3E086 AA22 AD04 BA04 BA15 BA24 BA35 BB22 BB54 BB72 CA11 DA01 DA08 4F006 AA35 AB35 AB56 BA16 CA07 4F100 AH00A AK25A AK41A AK41B AK52A AL01A BA02 BA16 CA18A CC00A DA01 DE01A GB16 JB09A JB12A JK16A JL16 JN01 YY00A 4J029 AA03 AB07 AC02 AD01 AE01 BA02 BA03 BA08 BA09 CB05 CB06 CC05 CC06 CH02 CH06 DB02 KB02

Claims (10)

[Claims] 1. A hollow hollow polyester product having a coat layer of polyester (A) on the outer surface, wherein the coat layer comprises organic particles (B) having an average particle size of 20 to 2000 nm based on the weight of the polyester (A). 5 to 20% by weight,
It can be removed with hot water of 70 to 100 ° C. or an alkaline aqueous solution having a pH of 10 or more, and the surface friction resistance is less than 0.1.
A hollow molded product made of polyester, characterized in that it is 1 to 0.4. 2. The polyester (A) contains 93 to 60 mol% of at least one unit selected from the group consisting of naphthalenedicarboxylic acid units, terephthalic acid units and isophthalic acid units, based on the total dicarboxylic acid component, and a metal sulfonate. The polyester hollow according to claim 1, which is a polyester comprising a dicarboxylic acid component composed of an isophthalic acid unit having a base in an amount of 7 to 40 mol% based on all dicarboxylic acid components, and a diol component composed of an aliphatic diol. Molded body. 3. The polyester hollow molded article according to claim 1, which has a haze of 10% or less. 4. The polyester hollow molded article according to claim 1, wherein the coat layer has a thickness of 0.1 to 10 μm. 5. A method for recycling a polyester hollow molded article, comprising removing the coat layer from the recovered polyester hollow molded article and forming a coat layer again, wherein the polyester hollow molded article is the polyester according to claim 1. A method for recycling a polyester hollow molded article, which is a hollow molded article made of polyester. 6. A method for producing a polyester hollow molded article, comprising the steps of removing a coat layer from the recovered polyester hollow molded article and subsequently forming a coat layer, the polyester hollow molded article. Is a polyester hollow molded article according to claim 1, and a method for producing a polyester hollow molded article. 7. The method for producing a polyester hollow molded article according to claim 5, wherein the step of removing the coat layer is a step including washing with warm water or an alkaline aqueous solution and subsequent washing with water. 8. A method for recycling a polyester hollow molded article, wherein the polyester hollow molded article is recycled by the recycling method according to claim 5 each time it is reused. 9. The polyester hollow molded article comprises a polyester hollow molded article body and a polyester coating layer formed on the outer surface thereof, wherein the polyester hollow molded article body is ethylene-2,6-naphthalene. The polyester hollow molded article according to claim 1, which comprises a thermoplastic polyester containing a dicarboxylate unit as a repeating unit in an amount of 5% by weight or more. 10. The polyester hollow molded article according to claim 1, which is a bottle.