JP2001179810A - Preform for multi-layer hollow molding, multi-layer hollow molding, and method for producing the molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a molding excellent in mechanical properties and its production method wherein the temperature difference between the inside layer and outside layer of the multi-layer preform can be decreased without using special equipment and a large amount of energy for heating and decreasing the temperature difference, and the molding cycle of the multi-layer hollow molding can be shortened and the stress distortion of the inside and outside layers of the hollow molding is controlled. SOLUTION: A preform for a multi-lay hollow molding is a bottomed cylinder having a multi-layer structure and is molded from a thermoplastic resin composition having an inner layer containing an infrared absorbent. The multi-layer hollow molding is made by blow-molding the preform. The method of manufacture comprises the steps of heating the bottomed cylindrical multi-layer preform having the inner layer containing the infrared absorbent by an infrared heater and blow-molding the preform so as to obtain the molding.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a multilayer preform for a multilayer hollow molded article, a multilayer hollow molded article produced from the multilayer preform, and a method for producing the same. More specifically, when producing a hollow molded article from a preform, a multilayer preform capable of reducing a temperature difference between an inner wall and an outer wall of the preform, a multilayer produced from the multilayer preform. The present invention relates to a hollow molded article and a method for producing the same.

[0002]

BACKGROUND OF THE INVENTION Generally, polyester resin hollow molded articles such as PET bottles have excellent mechanical properties, moisture and gas barrier properties, chemical resistance, fragrance retention, transparency and hygiene. Therefore, it has been widely used in recent years as containers for foods, pharmaceuticals, cosmetics, and the like. In general, many hollow molded articles made of polyester resin are formed by a so-called cold parison method. The cold parison method includes two molding steps. In a first step, a hollow preform of a test tube called a preform is injection molded to produce a hollow molded body. Then, in the second step, the preform is blow-molded in a mold with high-pressure air. In this second step, the preform is prior to blow molding,
The film is heated to a suitable stretching temperature (for example, about 100 ° C. for polyethylene terephthalate resin). In the heating step, generally, heating is performed from the outer surface side of the preform by an infrared heater. In the heating by the infrared heater, the outside of the preform becomes hotter than the inside. If blow molding is performed with a large temperature difference between the inside and outside of the preform, problems such as whitening of the resulting bottle, and stress distortion inside and outside, resulting in a decrease in mechanical properties will occur. Cannot be manufactured.
Therefore, it is manufactured by a method of heating the preform while making the inside and outside temperatures uniform over a long time, or a method of providing an equilibration time for making the inside and outside temperatures uniform after heating the preform. In these methods, there is a problem that the production efficiency remarkably deteriorates depending on the time taken for equalizing the inside and outside temperatures. To solve this problem, JP-A-61-163828 discloses a method in which a heat pipe is inserted into a preform and heated from inside and outside.
No. 77919 discloses a method of inserting a rod-shaped heater having a large diameter portion at an end inside a preform and heating from inside and outside,
JP-A-63-306023 discloses a method in which a heating element for radiating radiant heat is inserted into a preform and heating is performed from inside and outside, and JP-A-63-17026 discloses a method in which heating is performed by an infrared heater and then by a radio frequency heater. Japanese Unexamined Patent Publication No. Hei 8-142175 discloses a method of performing heating by dielectric heating after heating by an infrared heater, and Japanese Unexamined Patent Publication No. Hei 9-11325 discloses a method of blowing a cooling gas onto an outer surface after heating. It has been disclosed. However,
Each of these methods requires special equipment and requires a large amount of energy for heating and temperature uniformization.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned prior art, and has a special apparatus and a large amount of energy when manufacturing a multilayer hollow molded article from a preform for a multilayer hollow molded article. It is an object of the present invention to provide a preform for a multilayer hollow molded article capable of reducing the temperature difference between the inner and outer layers of the preform without requiring the above and reducing the molding cycle time of the multilayer hollow molded article.
Another object of the present invention is to provide a multilayer hollow molded article manufactured from the above-described preform for a multilayer hollow molded article, and a method for producing the same.

[0004]

SUMMARY OF THE INVENTION A preform for a multilayer hollow molded article according to the present invention is a preform for a multilayer hollow molded article for blow-molding a multilayer hollow molded article, wherein the preform has a bottomed structure having a multilayer structure. A cylindrical body, wherein the inner layer is formed of a thermoplastic resin composition containing an infrared absorber. Specific examples of the infrared absorber preferably used in the present invention include organic color materials, metal particles, carbon black and iron oxide, and these can be used alone or as a mixture. Further, as the thermoplastic resin composition preferably used in the present invention,
Examples thereof include a polyethylene terephthalate resin, a polyethylene naphthalate resin and a copolymerized polyester resin, and these may be used alone or as a mixture.

[0005] The multilayer hollow molded article according to the present invention is characterized in that the preform for the multilayer hollow molded article is blow molded. The method for producing a multilayer hollow molded article according to the present invention comprises a step of heating a bottomed cylindrical multilayer preform having an inner layer made of a thermoplastic resin composition containing an infrared absorbent with an infrared heater, followed by blow molding to form a multilayer hollow. It is characterized by obtaining a molded body.

[0006]

DETAILED DESCRIPTION OF THE INVENTION Hereinafter, a preform for a multilayer hollow molded article, a multilayer hollow molded article, and a method for producing the same according to the present invention will be specifically described.

A preform for a multilayer hollow molded article according to the present invention is a preform for a multilayer hollow molded article for blow molding a hollow molded article, wherein the preform is a bottomed cylindrical shape. The inner layer is made of a thermoplastic resin containing an infrared absorbent. Thermoplastic resin In the present invention,
Crystalline thermoplastic resins such as polyolefin, polyamide, polyester and polyacetal; polystyrene, acrylonitrile-butadiene-styrene copolymer (AB
Non-crystalline thermoplastic resins such as S), polycarbonate and polyphenylene oxide are preferably used.

[0008] Among these thermoplastic resins, it is particularly preferable to use a polyester resin in the present invention. Such a polyester resin forms a low-order condensate (ester low polymer) by an esterification reaction from an aromatic dicarboxylic acid or an ester-forming derivative thereof and an aliphatic diol or an ester-forming derivative thereof, and then forms a polymer. The low-order condensate can be produced by subjecting this low-order condensate to a deglycol-reaction (liquid-phase polycondensation) in the presence of a condensation catalyst to increase the molecular weight, and optionally performing solid-phase polycondensation.

Examples of the aromatic dicarboxylic acid used for producing the polyester resin include aromatic dicarboxylic acids such as terephthalic acid, phthalic acid, isophthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenoxyethanedicarboxylic acid and the like.

Examples of the aliphatic diol include aliphatic glycols such as ethylene glycol, trimethylene glycol, propylene glycol, tetramethylene glycol, neopentyl glycol, hexanemethylene glycol and dodecamethylene glycol.

In the production of the polyester resin, an aliphatic dicarboxylic acid such as adipic acid, sebacic acid, azelaic acid and decane dicarboxylic acid, and an alicyclic dicarboxylic acid such as cyclohexane dicarboxylic acid are used together with aromatic dicarboxylic acid as raw materials. Along with aliphatic diols, alicyclic glycols such as cyclohexanedimethanol, bisphenols, hydroquinones, 2,
2-bis (4-β-hydroxyethoxyphenyl) propane,
An aromatic diol such as 1,3-bis (2-dihydroxyethoxy) benzene can be used as a raw material.

Further, trimesic acid, trimethylolethane, trimethylolpropane, trimethylolmethane,
A polyfunctional compound such as pentaerythritol can be used as a raw material.

In the present invention, as the polyester resin,
In particular, polyethylene terephthalate and naphthalene dicarboxylic acid produced from terephthalic acid or its ester-forming derivative, ethylene glycol or its ester-forming derivative, and optionally an aromatic dicarboxylic acid other than terephthalic acid (eg, isophthalic acid) Polyethylene naphthalate produced from an acid or an ester-forming derivative thereof, ethylene glycol or an ester-forming derivative thereof, and an aromatic dicarboxylic acid other than naphthalenedicarboxylic acid, if necessary, a terephthalic acid component unit, 2,6- A dicarboxylic acid structural unit containing one or more of naphthalenedicarboxylic acid component units, isophthalic acid component units, and adipic acid component units; and an ethylene glycol component unit, a diethylene glycol component unit, and a neopentyl glycol component unit. It is preferable to use a copolymerized polyester resin formed from a dihydroxy compound structural unit containing one or more of cyclohexanedimethanol component units.

The above thermoplastic resins may be used alone or in combination of two or more. Infrared absorber The infrared absorber used in the present invention is not particularly limited, but those which do not decompose at the synthesis temperature of the thermoplastic resin and the molding temperature of the preform for the multilayer hollow molded article are preferable, and the multilayer hollow molded article has transparency. For applications that require it, those that absorb less electromagnetic waves in the visible region are preferred.

The infrared absorber preferably used in the present invention includes, for example, organic coloring materials, metal particles, carbon black, iron oxide and the like, and these may be used alone or as a mixture. Of these, a colored material is particularly preferably used in that the color of the hollow molded body is not changed.

The thermoplastic resin composition used in the present invention comprises the above-mentioned thermoplastic resin and such an infrared absorbing agent.
1 to 1000 ppm, more preferably 0.1 to 100 ppm
ppm, particularly preferably 0.5 to 50 ppm.

When the content of the infrared absorbent is in the above range, a resin composition having excellent heat absorbing function can be obtained. Organic Coloring Material The organic coloring material used in the present invention is preferably a phthalocyanine compound represented by the following general formula (1), a naphthalocyanine compound represented by the following general formula (2) and a general formula (3) shown below. It is desirable that at least one selected from anthraquinone compounds.

First, the phthalocyanine compound (1) and the naphthalocyanine compound will be described.

[0019]

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[0020]

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In the above general formulas (1) and (2), M is
A divalent metal atom, a trivalent substituted metal atom, a tetravalent substituted atom or an oxymetal is shown. Examples of the divalent metal atom include Cu (II), Zn (II), Fe (II), and Co (I
I), Ni (II), Ru (II), Rh (II), Pd (I
I), Pt (II), Mn (II), Mg (II), Ti (I
I), Be (II), Ca (II), Ba (II), Cd (I
I), Hg (II), Pb (II), Sn (II) and the like.

Examples of the trivalent substituted metal atom include A
lCl, AlBr, AlF, AlI, GaCl, Ga
F, GaI, GaBr, InCl, InBr, InI,
InF, TlCl, TlBr, TlI, TlF, FeC
1, RuCl, Al-C ₆ H ₅ , Al-C ₆ H ₄ (CH
_{3), In-C 6 H} 5, In-C 6 H 4 (CH 3), In-C
_{6 H 5, Mn (OH)} , Mn (OC 6 H 5), Mn [OS
i (CH ₃ ) ₃ ] and the like.

As the tetravalent substituent atom, for example, CrC
l ₂ , SiCl ₂ , SiBr ₂ , SiF ₂ , SiI ₂ ,
ZrCl ₂ , GeCl ₂ , GeBr ₂ , GeI ₂ , Ge
F ₂ , SnCl ₂ , SnBr ₂ , SnF ₂ , TiCl
₂ , TiBr ₂ , TiF ₂ , Si (OH) ₂ , Ge (OH)
₂ , Zr (OH) ₂ , Mn (OH) ₂ , Sn (OH) ₂ , Ti
R ₂ , CrR ₂ , SiR ₂ , SnR ₂ , GeR ₂ (where R represents an alkyl group, a phenyl group, a naphthyl group, and derivatives thereof), Si (OR ′) ₂ , Sn (OR ′)
₂ , Ge (OR ′) ₂ , Ti (OR ′) ₂ , Cr (OR ′) ₂ (where R ′ is an alkyl group, a phenyl group, a naphthyl group, a trialkylsilyl group, a dialkylalkoxysilyl group or a Derivatives are shown.), Sn (SR ″) ₂ , Ge
(SR ″) ₂ (where R ″ is an alkyl group, a phenyl group,
Indicates a naphthyl group or a derivative thereof. ) And the like.

Examples of oxymetals include VO, Mn
O, TiO and the like can be mentioned. Preferred M among these
Represents Cu (II), Pd (II), Pb (II), AlCl,
InCl, TiO or VO is particularly preferred.

A ^{1 to} A ¹⁶ and B ^{1 to} B ²⁴ may be the same or different from each other and represent a hydrogen atom, a halogen atom,
An alkyl group which may have a substituent, an aryl group which may have a substituent, an alkoxy group which may have a substituent, an aryloxy group which may have a substituent, An alkylthio group which may be substituted, an arylthio group which may have a substituent, an alkylamino group which may have a substituent, an arylamino group which may have a substituent, and the like.

Examples of the halogen atom include fluorine, chlorine, bromine and iodine. Examples of the alkyl group which may have a substituent include, for example, methyl, ethyl, n-propyl,
iso-propyl, n-butyl, iso-butyl, sec-butyl, n-
Pentyl, iso-pentyl, 1,2-dimethyl-propyl, n-
Hexyl, 1,3-dimethyl-butyl, 1,2-dimethylbutyl, n-heptyl, 1,4-dimethylpentyl, 1-ethyl-3-
Methylbutyl, n-octyl, 2-ethylhexyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, n-nonadecyl,
n-eicosyl, benzyl, sec-phenylethyl, 2-methylbenzyl, 3-methylbenzyl, 4-methylbenzyl,
2-phenylethyl, 3-dimethylaminopropyl, 2-dimethylaminoethyl, 2-diisopropylaminoethyl, 2-
Diethylaminoethyl, 2,2,2-trifluoro-1- (trifluoromethyl) ethyl, 2- (1-piperidinyl) ethyl, 3-
(1-piperidinyl) propyl, 3- (4-morpholinyl) propyl, 3- (4-morpholinyl) ethyl, 2- (1-pyrrolidinyl) ethyl, 2-pyridylmethyl, etc.
0, preferably 1 to 10 linear or branched alkyl groups, cyclopentyl, cyclohexyl, norbornyl,
3-20 carbon atoms such as adamantyl, preferably 3
And 10 to 10 cycloalkyl groups.

Examples of the aryl group which may have a substituent include phenyl, tolyl, dimethylphenyl, trimethylphenyl, ethylphenyl, propylphenyl, biphenylyl, 2-mercaptophenyl, 3-mercaptophenyl, 4-mercaptophenyl, 2-methylphenyl, 3-methylphenyl, 4-methylphenyl, naphthyl,
An aryl group having 6 to 20 carbon atoms, preferably 6 to 12 carbon atoms, such as methylnaphthyl, anthryl, and phenanthryl is exemplified.

Examples of the optionally substituted alkoxy group include, for example, methoxy, ethoxy, n-propoxy, iso-
Propoxy, n-butoxy, iso-butoxy, sec-butoxy, n-pentoxy, iso-pentoxy, n-hexyloxy, cyclohexyloxy, n-heptyloxy, n-octyloxy, 2-ethylhexyloxy, n-nonyloxy, methoxy C1-20 such as ethoxy, ethoxyethoxy, ethoxyethoxyethoxy, hydroxyethoxyethoxy, diethylaminoethoxy, aminoethoxy, n-butylaminoethoxy, benzylaminoethoxy, methylcarbonylaminoethoxy, phenylcarbonylaminoethoxy, benzyloxy, Preferably 1
And 10 to 10 alkoxy groups.

The aryloxy group which may have a substituent includes, for example, phenoxy, 2-methylphenoxy,
An aryloxy group having 6 to 20 carbon atoms, preferably 6 to 12 carbon atoms, such as methylphenoxy, 4-methylphenoxy, and naphthoxy is exemplified.

Examples of the alkylthio group which may have a substituent include methylthio, ethylthio, n-propylthio, iso-propylthio, n-butylthio, iso-butylthio, sec-butylthio, t-butylthio, n-pentylthio,
iso-pentylthio, neo-pentylthio, 1,2-dimethyl-
Propylthio, n-hexylthio, cyclohexylthio,
n-heptylthio, 2-ethylhexylthio, n-octylthio, n-nonylthio, methoxyethylthio, ethoxyethylthio, propoxyethylthio, butoxyethylthio,
Carbon such as aminoethylthio, n-butylaminoethylthio, benzylaminoethylthio, methylcarbonylaminoethylthio, phenylcarbonylaminoethylthio, methylsulfonylaminoethylthio, phenylsulfonylaminoethylthio, dimethylaminoethylthio, diethylaminoethylthio, etc. 1-20 atoms, preferably 1-1
And an alkylthio group of 0.

The arylthio group which may have a substituent includes, for example, phenylthio, naphthylthio, 4-methylphenylthio, 4-ethylphenylthio, 4-propylphenylthio, 4-t-butylphenylthio, 4-methoxy Phenylthio, 4-ethoxyphenylthio, 4-aminophenylthio, 4-alkylaminophenylthio, 4-dialkylaminophenylthio, 4-phenylaminophenylthio, 4-diphenylaminophenylthio, 4-hydroxyphenylthio, 4 -Chlorophenylthio, 4-bromophenylthio, 2-
Methylphenylthio, 2-ethylphenylthio, 2-propylphenylthio, 2-t-butylphenylthio, 2-methoxyphenylthio, 2-ethoxyphenylthio, 2-aminophenylthio, 2-alkylaminophenylthio, 2 -Dialkylaminophenylthio, 2-phenylaminophenylthio, 2-diphenylaminophenylthio, 2-hydroxyphenylthio, 4-dimethylaminophenylthio, 4-methylaminophenylthio, 4-methylcarbonylaminophenylthio, 4- Phenylcarbonylaminophenylthio, 4-
6-20 carbon atoms such as methylsulfonylaminophenylthio, 4-phenylsulfonylaminophenylthio,
Preferably, 6 to 12 arylthio groups are used.

The alkylamino group which may have a substituent includes, for example, methylamino, ethylamino, n-propylamino, iso-propylamino, butylamino, pentylamino, dipentylamino, hexylamino, heptylamino, octyl C 1-20, preferably 1-10 carbon atoms such as amino, nonylamino and benzylamino
And an alkylamino group of

The arylamino group which may have a substituent is, for example, phenylamino, 4-methylphenylamino, 4-methoxyphenylamino, hydroxyphenylamino, naphthylamino or the like having 6 to 20 carbon atoms, preferably 6 to 12 arylamino groups.

Of the groups represented by A ^{1 to} A ¹⁶ , two adjacent groups
Groups may be linked to form a 5- or 6-membered ring together with the carbon atoms to which they are attached, and two adjacent groups among the groups represented by B ^{1 to} B ²⁴ are linked to each other. May form a 5- or 6-membered ring together with the carbon atoms to which they are each bonded.

Of the groups represented by A ^{1 to} A ¹⁶ or B ^{1 to} B ²⁴ , two adjacent groups are linked to form a 5- or 6-membered ring together with the carbon atoms to which they are respectively bonded. Examples of the group include those shown below.

[0036]

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The above-mentioned alkyl group which may have a substituent, aryl group which may have a substituent, alkoxy group which may have a substituent, aryloxy group which may have a substituent, An alkylthio group which may have a group, an arylthio group which may have a substituent, an alkylamino group which may have a substituent and an arylamino group which may have a substituent, and A ^{1 to} A Of the groups represented by ¹⁶ or B ^{1 to} B ²⁴ , two adjacent groups are linked to form a 5- or 6-membered ring together with the carbon atom to which each is bonded,
It may further have a substituent. Examples of such a substituent include a halogen atom, an alkyl group which may have a substituent, an aryl group which may have a substituent, An alkoxy group which may have a group, an aryloxy group which may have a substituent, an alkylthio group which may have a substituent, an arylthio group which may have a substituent, And an arylamino group which may have a substituent.

As the substituent, acetyl group (methylcarbonyl group), propionyl, butyryl, iso-butyryl, valeryl, iso-valeryl, trimethylacetyl, hexanoyl, t-butylacetyl, heptanoyl, octanoyl, 2-ethylhexanoyl , Nonanoyl, decanoyl, undecanoyl, lauroyl, tridecanoyl, tetradecanoyl, pentadecanoyl, hexadecanoyl, heptadecanoyl, octadecanoyl, oleoyl, cyclopentanecarbonyl, cyclohexanecarbonyl, 6-chlorohexanoyl, 6-bromohexanoyl ,
Trifluoroacetyl, pentafluoropropionyl,
Alkyl such as perfluorooctanoyl, 2,2,4,4,5,5,7,7,7-nonafluoro-3,6-dioxaheptanoyl, methoxyacetyl, 3,6-dioxaheptanoylarylcarbonyl Carbonyl group; benzoyl, o-chlorobenzoyl, m-chlorobenzoyl, p-chlorobenzoyl, o-fluorobenzoyl, m-fluorobenzoyl, p-fluorobenzoyl, o-acetylbenzoyl, m-acetylbenzoyl, p-acetylbenzoyl, o-methoxybenzoyl,
and arylcarbonyl groups such as m-methoxybenzoyl, p-methoxybenzoyl, o-methylbenzoyl, m-methylbenzoyl, p-methylbenzoyl, pentafluorobenzoyl, and 4- (trifluoromethyl) benzoyl.

Further, as a substituent, a heterocyclic compound residue; an ester group, an ether group, an acyl group, a carboxyl group, a carbonate group, a hydroxy group, a peroxy group,
Oxygen-containing groups such as carboxylic anhydride groups; amino groups, imino groups, amide groups, imide groups, hydrazino groups, hydrazono groups, nitro groups, nitroso groups, cyano groups, isocyano groups,
A nitrogen-containing group such as a cyanate ester group, an amidino group, a diazo group or an amino group having an ammonium salt; a boron-containing group such as a boranediyl group, a borantoriyl group or a diboranyl group; a mercapto group, a thioester group, a dithioester group; Alkylthio group, arylthio group, thioacyl group, thioether group, thiocyanate ester group, isothiocyanate ester group, sulfone ester group, sulfonamide group, thiocarboxyl group, dithiocarboxyl group,
Sulfur-containing groups such as a sulfo group, a sulfonyl group, a sulfinyl group, and a sulfenyl group; and a phosphorus-containing group such as a phosphide group, a phosphoryl group, a thiophosphoryl group, and a phosphato group, a silicon-containing group, a germanium-containing group, and a tin-containing group. Can be

A ^{1 to} A ¹⁶ and B ^{1 to} B ^{24 each} represent a hydrogen atom, a halogen atom, an alkoxy group which may have a substituent, an aryloxy group which may have a substituent, or a substituent. An arylthio group which may be substituted, an arylamino group which may have a substituent and the like are preferable.

The anthraquinone compound (3) is represented by the following general formula (3)

[0042]

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[Wherein the benzene rings A, B, C, and D are the same or each independently a straight-chain or branched alkyl group or cycloalkyl group having 1 to 20 carbon atoms, 20 linear or branched alkoxy groups, trifluoromethyl groups, or halogen atoms].

In the above formula (3), the number of carbon atoms is 1 to 2
As a linear or branched alkyl group of 0, for example,
Methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl, n-pentyl, iso-pentyl, 1,2-dimethyl-propyl, n-hexyl, 1,3-dimethyl- Butyl, 1,2-dimethylbutyl, n-heptyl, 1,4-dimethylpentyl, 1-ethyl-3-methylbutyl, n-octyl, 2-ethylhexyl, n-nonyl, n-decyl, n-undecyl, n- Dodecyl, n-tridecyl, n-tetradecyl, n-
Pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, n-nonadecyl, n-eicosyl, benzyl,
sec-phenylethyl, 2-methylbenzyl, 3-methylbenzyl, 4-methylbenzyl, 2-phenylethyl, 3-dimethylaminopropyl, 2-dimethylaminoethyl, 2-diisopropylaminoethyl, 2-diethylaminoethyl, 2,
2,2-trifluoro-1- (trifluoromethyl) ethyl, 2-
Carbons such as (1-piperidinyl) ethyl, 3- (1-piperidinyl) propyl, 3- (4-morpholinyl) propyl, 3- (4-morpholinyl) ethyl, 2- (1-pyrrolidinyl) ethyl, 2-pyridylmethyl 1-20 atoms, preferably 1-10 atoms
A linear or branched alkyl group.

Examples of the cycloalkyl group include cyclopentyl, cyclohexyl, norbornyl,
3-20 carbon atoms such as adamantyl, preferably 3
And 10 to 10 cycloalkyl groups.

The straight-chain or branched alkoxy group having 1 to 20 carbon atoms includes, for example, methoxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy, iso-
Butoxy, sec-butoxy, n-pentoxy, iso-pentoxy, n-hexyloxy, cyclohexyloxy, n-heptyloxy, n-octyloxy, 2-ethylhexyloxy, n-nonyloxy, methoxyethoxy, ethoxyethoxy, ethoxyethoxyethoxy , Hydroxyethoxyethoxy, diethylaminoethoxy, aminoethoxy,
1-2 carbon atoms such as n-butylaminoethoxy, benzylaminoethoxy, methylcarbonylaminoethoxy, phenylcarbonylaminoethoxy, and benzyloxy
0, preferably 1 to 10 alkoxy groups.

Examples of the halogen atom include fluorine, chlorine, bromine and iodine. The organic colorant used in the present invention is at least one selected from a phthalocyanine compound represented by the general formula (1), a naphthalocyanine compound represented by the general formula (2), and an anthraquinone compound represented by the general formula (3). Is a kind, the wavelength showing the maximum absorption peak of infrared ray is 700 to 2000 nm,
Preferably it is in the range of 750-2000 nm. When the wavelength showing the maximum absorption peak of infrared rays falls within such a range, the organic coloring material has excellent near-infrared absorption.

In the present invention, the maximum infrared absorption peak of the organic coloring material is measured as follows. An organic colorant is added to the polyester used for molding, and a 4 mm-thick plate-like molded body is produced by an injection molding machine at a molding temperature of 280 ° C. and a mold temperature of 10 ° C., and the plate-like molded body is used. And measured with a spectrophotometer UV-3100 manufactured by Shimadzu Corporation.

The organic colorant used in the present invention preferably has low absorption of electromagnetic waves in the visible region, and preferably does not decompose at the synthesis temperature of the polyester resin and the molding temperature of the preform, for example, 260 to 320 ° C. Metal particles, carbon black, iron oxide Metal particles preferably used in the present invention include, for example, metal particles described in JP-A-3-230933. Specifically, antimony, tin,
It is preferably copper, silver, gold, arsenic, cadmium, mercury, lead, palladium, platinum or a mixture of two or more thereof, and more preferably antimony, tin, copper or a mixture of two or more thereof. Particularly preferably, it is antimony. Further, for example, the metal compound may be reduced by mixing fine particles of the metal compound together with the reducing agent in the resin to obtain desired metal particles.

The metal particles are desirably fine enough to be indistinguishable to the naked eye. The metal particles preferably have a particle size of 5 nm to 500 nm, more preferably 10 nm.
m to 100 nm is desirable.

As the carbon black preferably used in the present invention, generally known carbon black can be used, and it is not particularly limited. For example, Japanese Patent Publication No. Hei 5-21938 or Japanese Patent Laid-Open Publication No. Hei 5-27809 is used.
No. 9 can be used. Specifically, channel black such as active black and hard black, and furnace black can be preferably used. The average particle size of such carbon black is preferably 10 to 500 n.
m, particularly preferably 10 to 100 nm, and more preferably 15 to 30 nm.

As the iron oxide preferably used in the present invention, generally known ferric oxide (Fe ₂ O ₃ ) can be used and is not particularly limited.
JP-A-5-50055 or JP-A-2-281070
Can be used. In particular,
Iron oxide having a composition of Fe ₂ O ₃ , Fe ₂ O ₃ .xH ₂ O or spherical iron oxide having a hematite structure can be used. Moreover, triiron tetraoxide as described in JP-A-11-236440 (Fe ₃ O ₄₎ may also be used.

The average particle size of the iron oxide used in the present invention is preferably from 10 to 500 nm, particularly preferably from 10 to 500 nm.
１００100 nm, more preferably 15-40 nm
It is desirable that Thermoplastic resin composition The method for preparing the thermoplastic resin composition can employ any of the conventionally known methods. In the production of the thermoplastic resin, for example, the infrared absorption in the esterification step or the polycondensation step of the polyester resin. There is a method of adding an agent, a method of mixing a thermoplastic resin and an infrared absorbing agent, and heating and kneading the mixture.

Incidentally, the thermoplastic resin composition may contain additives such as a hue regulator, an antistatic agent, an ultraviolet absorber, an antioxidant and a release agent which are usually added to the thermoplastic resin. Good. The preform for a multilayer hollow molded article The preform for a multilayer hollow molded article according to the present invention has a bottomed cylindrical shape, and its wall is formed in multiple layers. The inner layer of the preform for a multilayer hollow molded article according to the present invention is formed of a thermoplastic resin containing an infrared absorbent as described above.

In this specification, the term “inner layer” means the innermost layer constituting the inner wall surface of the preform wall. Further, the multilayered wall may have an intermediate layer between the innermost layer and the outermost layer.

The preform for a multilayer hollow molded article according to the present invention can be formed by a conventionally known method using the thermoplastic resin composition. For example, from the above-mentioned thermoplastic resin composition, first, a preform for a multilayer hollow molded body of an inner layer portion is formed by injection molding, and then, the preform of the inner layer portion is set in a mold, and a further outer layer is formed. Is injected by injection molding or the like to form an outer layer and form a multilayer preform. If desired
Further outer layers can be formed in a similar manner.

The heating temperature of the thermoplastic resin at the time of forming the preform for the multilayer hollow molded article varies depending on the thermoplastic resin used. For example, when the polyester resin is polyethylene terephthalate, the heating temperature is preferably 270 to 300 ° C. 2 for polyethylene naphthalate
The temperature is preferably from 80 to 320 ° C.

The ratio of the thickness of the inner layer to the total thickness of the preform for a multilayer hollow molded article can be in the range of 1 to 99% if possible in the molding step. The thickness range that matches the purpose can be selected depending on the required properties such as the effect of the infrared absorber, the amount added, the hue of the hollow molded article, and the draw ratio.

Since the thus obtained preform for a multilayer hollow molded article is formed from the above-mentioned thermoplastic resin composition containing the above-mentioned infrared absorbing agent, it can be used as a preform.
The near-infrared heater having the maximum emission wavelength in the range of 00 to 2000 nm is excellent in the ability to absorb infrared rays emitted, and the inner layer is heated to the appropriate stretching temperature in a shorter time than before. Multilayer hollow molded article The multilayer hollow molded article according to the present invention is a thermoplastic resin composition in which the inner layer contains a specific infrared absorber, for example,
It is a hollow molded body manufactured by the cold parison method.

In such a multilayer hollow molded article, the preform for the multilayer hollow molded article is heated to an appropriate stretching temperature, and then the preform for the multilayer hollow molded article is held in a mold having a desired shape. It can be manufactured by blowing and attaching to a mold.

More specifically, the preform for a multilayer hollow molded article is heated to an appropriate stretching temperature using a near-infrared heater and blow-molded. The heating temperature at the time of blow molding varies depending on the thermoplastic resin used. For example, when the thermoplastic resin is polyethylene terephthalate, it is usually preferably 90 to 125 ° C, particularly preferably 100 to 120 ° C, and polyethylene naphthalate. In some cases, the temperature is desirably 115 to 150 ° C, preferably 120 to 140 ° C.

[0062]

According to the present invention, the inner layer of a preform having a multilayer structure is made of a thermoplastic composition having an enhanced heat absorbing ability. The temperature difference with the outer layer can be reduced in a short time. For this reason, when manufacturing a multilayer hollow molded article from a multilayer preform by blow molding, a special device for reducing the temperature difference between the inner and outer layers of the multilayer preform is not required. The temperature difference between the inner and outer layers of the preform can be reduced without requiring a large amount of energy, and the molding cycle time of the multilayer hollow molded article can be shortened. Further, according to the present invention, there is provided a hollow molded article having excellent mechanical properties, in which the stress and strain of the inner and outer layers of the multilayer hollow molded article obtained by blow-molding the multilayer preform as described above are suppressed, and excellent mechanical properties. can do.

[0063]

EXAMPLES Hereinafter, the present invention will be described more specifically based on examples, but the present invention is not limited to these examples.

[0064]

Example 1 A powder-form polyethylene terephthalate having an intrinsic viscosity of 0.83, previously frozen and pulverized, was treated at 150 ° C. with 1
Vacuum dried for 0 hours. The polyethylene terephthalate 9
Infrared absorbent No. 1 shown in Table 1 with respect to 9.9 parts by weight
And 0.1 parts by weight of the mixture, using a modern machine single screw extruder with a screw diameter of 40 mm, at an extrusion temperature of 260 ℃ P
The ET resin was extruded into strands, which were cut to produce masterbatch pellets containing an infrared absorbent.

To 95 parts by weight of the polyethylene terephthalate pellets having an intrinsic viscosity of 0.83 used above, 5 parts by weight of the above-prepared master batch pellets containing an infrared absorbent were mixed (infrared absorbent concentration: 50 ppm).
Vacuum dried at 50 ° C. for 10 hours. The mixed pellets were molded at a molding temperature of 280 using a Meiki Seisakusho M-100 injection molding machine.
At 1.8 ° C. and a mold temperature of 10 ° C., a 1.8-mm thick inner layer portion of a preform of a 1.5-liter bottle was prepared. Subsequently, the preform inner layer was set in a mold,
The same polyethylene terephthalate having an intrinsic viscosity of 0.83, which was vacuum-dried for a period of time, was injected at a molding temperature of 280 ° C. and a mold temperature of 10 ° C. using a Meiki M-100 injection molding machine to obtain a two-layer preform. Molded.

Using a biaxially stretched flow molding machine (type: LB01) manufactured by Corpoplast, the two-layer preform was heated with an infrared heater for 60 seconds, and then the temperature of the preform was measured. Table 2 shows the measurement results.

[0067]

Examples 2 to 4 No. 2 to No. 2 shown in Table 1
A two-layer preform was formed in the same manner as in Example 1 except that the preform was changed to 4. In the same manner as in Example 1, the preform was heated by an infrared heater for 60 seconds, and then the temperature of the preform was measured. Table 2 shows the measurement results.

[0068]

Examples 5 to 16 No. 5 of the infrared absorbing agent shown in Table 1
A two-layered preform was formed in the same manner as in Example 1 except that the concentration of the infrared absorbent in the inner layer was changed to 10 ppm instead of the preform. In the same manner as in Example 1, after heating the preform with an infrared heater for 60 seconds,
The temperature of the preform was measured. Table 2 shows the measurement results.

[0069]

[Comparative Example 1] Intrinsic viscosity 0.8 without adding an infrared absorber
A preform was prepared using only the polyethylene terephthalate pellets No. 3. After heating the preform with an infrared heater for 60 seconds in the same manner as in Example 1, the temperature of the preform was measured. Table 2 shows the measurement results.

[0070]

[Table 1]

[0071]

[Table 2]

[0072]

[Table 3]

[0073]

[Table 4]

[0074]

[Table 5]

[0075]

[Table 6]

[0076]

[Table 7]

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) // B29K 67:00 B29K 67:00 B29L 22:00 B29L 22:00 (72) Inventor Osamu Takago Mayor of Sodegaura, Chiba Prefecture Uraji Takuji No. 580-32 Mitsui Chemicals Co., Ltd. F-term (reference) 4F100 AA23A AA37A AB01A AK01A AK01B AK41A AK42A AL01A BA02 CA13A CA30A DA01 DE01A GB16 JB16A JD10A 4F201 AA24 AA26 AB01 AB12 BC18 BC05 BC03 BC03 BM13 BM14 4F208 AA24 AA26 AB01 AB12 AB18 AK05 LA04 LA08 LB22 LG03 LG06 LG28 LH06 LN11

Claims (5)

[Claims] 1. A preform for a multi-layer hollow molded article for blow molding a multi-layer hollow molded article, wherein the preform is a bottomed cylinder having a multi-layer structure, and an inner layer of the preform is an infrared absorbent. A preform for a multilayer hollow molded article, which is formed from a thermoplastic resin composition containing the same. 2. The preform for a multilayer hollow molded article according to claim 1, wherein the infrared absorber is an organic coloring material, metal particles, carbon black or iron oxide. 3. The preform for a multilayer hollow molded article according to claim 1, wherein the thermoplastic resin composition comprises a polyethylene terephthalate resin, a polyethylene naphthalate resin, or a copolymerized polyester resin. 4. A multilayer hollow molded article obtained by blow molding the preform for a multilayer hollow molded article according to any one of claims 1 to 3. 5. A multi-layer hollow molded body obtained by heating a bottomed cylindrical multilayer preform having an inner layer made of a thermoplastic resin composition containing an infrared absorbing agent with an infrared heater, followed by blow molding. For producing a multilayer hollow molded article.