JPS59199428A - Matte hollow vessel made of polyethylene terephthalate groupresin - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a matte hollow container made of polyethylene terephthalate resin, and more specifically, a polyethylene terephthalate resin having an excellent matte surface and pearl-like color tone (pattern). This invention relates to a matte hollow container made of resin.

[Disadvantages of conventional technology] Polyethylene terephthalate resin, which contains ethylene terephthalate as its main component, has excellent impact resistance, gas barrier properties, and solvent resistance. It has come to be used as a material for food packaging bottles, camp products, and lée. In addition, such polyester resin does not contain any additives such as stabilizers that can be leached onto the surface of the bottle, and has excellent fragrance retention and gloss. There has been a demand for the development of a polyethylene terephthalate resin bottle that has a matte surface similar to that of a corroded crow bottle in addition to the characteristics described in L above.

In general, methods for matting thermoplastic resins are roughly divided into the following three methods.

(1) A method of adding an inorganic matting agent to the resin. (2) A method of molding using a drawing die. (3) A method of performing post-processing such as painting and sandblasting. The method of adding fine inorganic powder to resin is effective when mixed with powdered resin, but since a suitable amount of the powder must be uniformly combined with the resin, it requires )
It was difficult to apply this method when adding to resins that are usually obtained in pellet form, such as ethylene terrescrete.

The method of using a mold with a single force or aperture is an effective method when the resin is heated to a fluid state and then molded, as in injection molding or extrusion molding. However, polyethylene terephthalate resin bottles are molded using a new method called stretch blow molding, and in this method the resin temperature during molding is 1.
Because the temperature was as low as around 00°C, when molding polyethylene terephthalate resin bottles, it was not possible to sufficiently transfer the drawing pattern of the mold.

Furthermore, depending on the coating method, a good surface hardness and matte effect can be obtained, but in the case of polyethylene terephthalate, it is still possible to obtain a coating film with sufficient electrodeposition strength. It has not been done.

Furthermore, although sandblasting can provide a good matte surface, it has the disadvantage that the surface hardness of the molded product obtained is low and transparent scratches are easily formed.

As described above, it has been difficult to apply a matte finish to polyethylene terephthalate resin bottles using conventional methods. development was desired.

[Objective of the Invention 1 The present invention provides a matte hollow container made of polyethylene terephthalate resin that has a good matte surface and a pearl-like color tone (pattern) that has not been seen in the past. The purpose is to

[Configuration 1 of the Invention The matte hollow container made of polyethylene terephthalate resin of the present invention contains more than 50% by weight of vinyl aromatic heptamer and 80% by weight.
% by weight or less, having an alkyl group having 1 to 13 carbon atoms (
meth)acrylic acid alkyl ester 10% by weight or more 50
100 parts by weight of a non-crosslinkable monomer consisting of less than 0% by weight and 0 to 40% by weight of a monoethylenically unsaturated monomer other than the vinyl aromatic monomer and the ester;
Average particle size 35-50011- obtained by suspension polymerization with 0.5-5 parts by weight of an allyl compound having 5 double bonds and 0-5 parts by weight of a crosslinkable monomer other than said compound;
After blending 5 to 45 parts by weight of a crosslinkable polymer of m and 55 to 95 parts by weight of polyethylene terephthalate and/or its copolymer having an intrinsic viscosity of 0.5 to 1.5, this is preformed, and then It is characterized by being obtained by biaxial stretch blow molding.

The present invention will be explained in detail below.

First, the monomer composition of the crosslinked polymer matting agent used in the present invention will be explained. Regarding the composition,
It is described in detail in JP-A-58-38535.

The monomers constituting the crosslinked polymer matting agent are broadly classified into non-crosslinkable monomers and crosslinkable monomers. Examples of non-crosslinking monomers include vinyl aromatic monomers, carbon atoms of 1 to
(Meth)acrylic acid alkyl esters having 13 alkyl groups and, if necessary, monoethylenically unsaturated monomers are used. The blending amounts are 50 to 90% by weight of the vinyl aromatic heptanomer, 10 to 50% by weight of the (meth)acrylic acid alkyl ester, and 0 to 40% by weight of the monoethylenically unsaturated monomer.

Specific examples of vinyl aromatic monomers include styrene, vinyltoluene, α-methyltoluene, halogenated styrene, and the like.

Preferred specific examples of (meth)acrylic alkyl esters include lower esters such as ethyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate-1, methyl methacrylate, ethyl methacrylate-1, and n-butyl methacrylate. Examples include meth)acrylic buty alkyl esters.

Monoethylenically unsaturated monomers include, for example, unsaturated carboxylic acids or esters thereof, such as tuacrylic acid, fumaric acid, maleic acid, etc.
Excluding (meth)acrylic alkyl esters having an alkyl group of 3]: vinyl esters such as hinyl chloride, hinyl bromide, and vinyl acetate; and hinyl nitriles such as acrylonitrile.

As the crosslinking compound, an allyl compound having 2 to 5 unsaturated bonds in the molecule is used, or other crosslinking compounds may be used as required. Representative examples of allyl compounds include allyl methacrylate, triallyl cyanurate, and triallyl isocyanurate. These allyl compounds are generally used in an amount of 0.5 to 5 parts by weight per 100 parts by weight of the non-crosslinking compound. In addition, when other crosslinkable monomers are not used, it is preferable to use them in a range of 1.5 to 4 parts by weight. The use of this allyl compound is important in providing an appropriate crosslinking distribution within the crosslinkable polymer. In addition, as crosslinking monomers other than allyl compounds,
Unsaturated carbonic acid esters of alkylene glycol such as ethylene glycol dimethacrylate; ethers of alkylene glycol and unsaturated alcohol such as propylene glycol diallyl ether; polyvalent vinylpencenes such as divinylbenzene. Crosslinking monomers other than these allyl compounds are non-crosslinking monomers 1
00 parts by weight, it is usually used in a range of 0 to 5 parts by weight. In addition, when using the allyl compound (Jl), it is preferable to use 1.5 to 5 parts by weight of the total amount of crosslinking monomers based on 100 parts by weight of non-crosslinking heptamer.

The second non-crosslinking monomer and crosslinking monomer are polymerized by a suspension polymerization method to form a matting agent. When carrying out suspension polymerization, a polymerization initiator and a suspension stabilizer are usually used, and any of those used in normal suspension polymerization can be used. Typical examples of polymerization initiators include organic peroxides such as benzoyl peroxide and lauroyl peroxide, and aso compounds such as azobisisobutyronitrile, and examples of suspension stabilizers include polyvinyl alcohol and polyvinyl alcohol. Examples include organic colloidal polymer substances such as acrylates, carboxymethyl cellulose, gelatin, and tragacanth; inorganic colloidal substances such as barium sulfate, magnesium carbonate, and calcium phosphatide; and combinations of these with surfactants.

It is also possible to carry out suspension polymerization using a polymerization regulator. When this is used, the molecular distribution can be adjusted, so it is often preferable. Examples of such polymerization regulators include n-octyl mercaptan and tert-dodecyl mercaptan.

The polymerization reaction is usually carried out by suspending the compound in water with a polymerization initiator in the presence of a suspension stabilizer, but in addition to this, a soluble polymer may be added to the monomer, or a crosslinkable It is possible to polymerize a part of a non-crosslinkable monomer in bulk without adding a polymer, and then add a crosslinkable polymer, a suspension stabilizer, and the like.

After the above suspension polymerization is completed, the reaction 82 mixture is dehydrated, washed, and dried according to a conventional method to obtain a granular crosslinked polymer. In the present invention, the average particle diameter of the obtained particles is usually 35 to 500 gm, preferably 40 to 2 gm.
A crosslinked polymer in the range of 0.00 gm is used as a matting agent for hollow containers made of polyethylene terephthalate resin. Such a particle size is a feature of the present invention. If the average particle size is less than 35 gm, the matting effect will not be sufficient, and if it exceeds 500 gm, the surface of the resulting molded product will be rough and it will be difficult to obtain a uniform matte surface. The above matting agents are polyethylene terephthalate-1.
After being mixed with a system resin, it is molded into a hollow container. The polyethylene terephthalate resin used in the present invention is used alone or as a copolymer thereof, and its intrinsic viscosity is usually in the range of 0.5 to 1.5, preferably 0.6 to 1.2. things are used. Examples of monomers constituting the copolymer include phthalic acid,
Examples include acid components such as isophthalic acid and adipine; glycol components such as propylene glycol, trimethylene glycol, and tetramethylene glycol. These monomers are generally used in an amount of 1 to 20% by weight, preferably 5 to 15% by weight in the copolymer.

The above-described matting agent is usually blended in an amount of 5 to 45 parts by weight, preferably 10 to 30 parts by weight, per 100 parts by weight of the polyethylene terephthalate resin. The hollow container is
It is usually obtained by mixing a predetermined amount of both, forming pellets, drying the pellets, preforming them to form a preform, and then molding this using a stretch blow molding machine. That is, first, the polyethylene terephthalate resin is sufficiently dried to have a moisture content of 1100 pp or less, and a predetermined amount of the matting agent is added thereto, followed by injection molding or extrusion molding. At this time, the cylinder temperature is usually 260 to 30
0°C2, preferably 270-290°C. Thereafter, the obtained preform itself is heated to usually 75 to 150°C, preferably 80 to 120°C, and a mandrel is pushed down, and pressurized air of usually 10 to 25 kg/C'lf is blown into the preform. The hollow container of the present invention is obtained by stretch blow molding. The stretching ratio at this time is an area ratio, and is usually in the range of 2 to 15 times, preferably 4 to 10 times.

Note that the hollow container referred to in the present invention is not limited to the shape of a bottle, etc.
It may have any shape as long as it has a so-called hollow part. Moreover, the application is not limited to containers for cosmetics, but may be related to any application.

[Effect 1 of the invention] A hollow container made by blending the crosslinked polymer matting agent according to the present invention with a polyethylene terephthalate resin and biaxially stretching blow molding has a good matte surface and is better than the conventional one. It has a pearl-like color tone (pattern) originating from the polymer structure inside the container, which was not seen in the original container.

[Examples of the Invention] The values of intrinsic viscosity [η] in the following examples are values measured at 25°C after dissolving a polymer in a mixed solvent of phenol/tetrachloroethane (50150ff1i ratio). Moreover, parts represent parts by weight.

(1) Production of crosslinked polymer The following compounds were charged into a reaction vessel equipped with a stirrer, a reflux condenser, and one nitrogen gas inlet.

Stine
70 parts ethyl acrylate
30 parts allyl methacrylate 2.
5 parts n-octyl mercaptan 0.1 part lauroyl peroxide 0.5 part polyvinyl alcohol 0.5 part water
After the inside of the 200-part container was sufficiently purged with nitrogen gas, the above compound was heated to 75°C without stirring to proceed with polymerization in a nitrogen atmosphere. 85℃ after 3 hours
The temperature was raised to 95°C and held for 3 hours, and then the temperature was raised to 95°C and held for 1 hour to complete polymerization, followed by dehydration, washing, and drying to obtain a granular crosslinked polymer.

The obtained particles had the following particle size distribution.

1 presentation y 24 or less 1.2 24-32 33.2 32-48 33.5 48-100 30.1100-
150 1.5 150-200 0.4 200 or more 0.1 Moreover, the particle size distribution from the micrograph was as follows.

Syudou Melon M 500 p-m or more 1.8 For 300-500 m6.7 150-300 gm 36.0 100-150 gm 14.875-1
00 grr+ -9,550~75 lm 20.3 25~50 p-m 9.7251 or less
1.2 (2) Production of matte bottle made of polyethylene terephthalate resin 20% by weight of the crosslinked polymer was mixed with polyethylene terephthalate having an intrinsic viscosity of 0.73, and the mixture was extruded into pellets using an extruder with a diameter of 40 mm.

The obtained pellets were vacuum dried at 150° C. for 15 hours, and then injection molded into a preform having a wall thickness of 3 mm, an outer diameter of 25 mm, and a total length of 134 mm. The cylinder temperature at this time was 280°C.

Next, a bottle having a body diameter of 54 cm and a total length IB of 8 mm was molded from the preform using a homemade stretch blow molding machine.

The temperature of the preform at this time was 90° C., and the blowing pressure of pressurized air was 10 kg/cm. Furthermore, the stretching ratio was 3.6 times in terms of area ratio. The bottle thus obtained was uniform and glossy.

On the other hand, as a comparative example, a mixture of 10% by weight of quartz powder and a mixture of 10% by weight of calcium carbonate powder was used instead of the crosslinked polymer as a matting agent, and these were extruded and pelletized. Bottles were manufactured in a similar manner.

The resulting bottle had poor dispersion of quartz powder and calcium carbonate powder, and had a significantly inferior appearance.

Claims (1)

Scope of Claims: More than 50% by weight and less than 90% by weight of a vinyl aromatic monomer, (meth)acrylic buty-alkyl ester having an alkyl group having 1 to 13 carbon atoms 10% by weight or more and less than 50% by weight, and the vinyl aromatic monomer 100 parts by weight of a non-crosslinked monomer consisting of 0 to 40*% by weight of a monoethylenically unsaturated monomer other than the monomer and the ester; 05 to 5 parts by weight of an allyl compound having 2 to 5 double bonds in the molecule; 0 to 5 parts by weight of a crosslinkable monomer other than the above compound; 5 to 45 parts by weight of a crosslinkable polypropylene having an average particle diameter of 35 to 500 Lulo obtained by suspension polymerization; and an intrinsic viscosity of 0.5 to 1. 55 to 85 parts by weight of polyethylene terephthalate and/or its copolymer of No. 5; is preformed and then biaxially stretched.