JP2005247372A - Blow-molded container for heating protected against sebum whitening and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a container suitable for medicine and food, which is excellent in solvent crack resistance and does not undergo whitening after the container is repeatedly subjected to steam sterilization in an microwave oven with sebum adhering thereon. <P>SOLUTION: The container is formed by blow-molding an alicyclic structure containing polymer resin, and urethane-based transparent ink is printed on at least part of the external surface, to obtain the blow-molded container for heating. The urethane-based transparent ink is preferably two-component urethane resin ink. A manufacturing method of the blow-molded container for heating includes the steps of framing the external surface of the blow-molded container made of the alicyclic structure containing polymer resin, and then silk-screen-printing the urethane-based transparent ink on at least part of the external surface. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a blow molded container, and more particularly, to a sebum whitening-resistant blow molded container suitable as a pharmaceutical container or a food container.

Conventionally, glass containers for pharmaceutical containers and food containers have been used, but plastic containers are being replaced from the viewpoints of weight reduction and easy disposal. Under such circumstances, it has been reported that a container made of a thermoplastic norbornene resin is suitable for a pharmaceutical container or a food container because it is excellent in transparency, heat resistance, chemical resistance and low elution.
Among the thermoplastic norbornene resin containers as described above, a container formed by blow molding may be whitened particularly when sebum adheres, and various studies have been conducted.

  Cited Document 1 discloses a method in which only the outer surface portion of a preform made of a cyclic olefin copolymer is blow-molded in a state where the molecular orientation is relaxed or higher, and the outer surface of the molded container after the container is molded. Discloses a method of heat-treating at a temperature of 130 ° C.

Japanese Patent Laid-Open No. 10-181735

However, nowadays, it has been used for baby bottles and the like that are sterilized with steam using a microwave oven with a significant amount of sebum attached, and conventional solvent crack resistance and sebum whitening resistance may not be sufficient. Therefore, higher solvent crack resistance and sebum whitening resistance have been demanded.
For example, a container obtained by the method described in Patent Document 1 may be whitened or ruptured when the solvent or sebum adheres, or whitening may occur in the sebum-adhered part when the container is heated with sebum attached. It was.
Therefore, an object of the present invention is to provide a container suitable for pharmaceuticals and foods, which has excellent solvent crack resistance and does not whiten even when repeated steam sterilization with a microwave oven with sebum attached. is there.

  As a result of intensive studies in order to solve the above problems, the present inventors have found that the urethane-based transparent ink has excellent adhesion to the alicyclic structure-containing polymer resin, and further has a urethane-based transparent on the outer surface. A blow molded container made of an alicyclic structure-containing polymer resin printed with ink has excellent solvent crack resistance, and it is found that whitening does not occur even when steam sterilization is repeated in a state where sebum is attached, Based on this knowledge, the present invention has been completed.

Thus, according to the present invention, there is provided a container formed by blow-molding an alicyclic structure-containing polymer resin, and a blow-formed container for heating formed by printing urethane-based transparent ink on at least a part of the outer surface. The urethane-based transparent ink is preferably a two-component urethane resin.
Moreover, the blow-molded container for heating is suitable as a baby bottle, and more suitable as a baby bottle for microwave steam sterilization.
Furthermore, after the outer surface of a blow molded container made of an alicyclic structure-containing polymer resin is subjected to frame treatment, at least a part of the outer surface is subjected to silk screen printing with urethane-based transparent ink to produce a blow molded container for heating. A method is provided.

  The blow-molded container for heating of the present invention is suitable as a baby bottle or the like because it is excellent in solvent crack resistance and is not deformed or whitened even when steam sterilized by a microwave oven with sebum attached.

  The blow-molded container for heating of the present invention is obtained by printing urethane-based transparent ink on at least a part of the outer surface of a base material made of an alicyclic structure-containing polymer resin.

(Alicyclic structure-containing polymer resin)
The alicyclic structure-containing polymer resin used in the present invention contains an alicyclic structure in the repeating unit of the polymer, and has the alicyclic structure in either the main chain or the side chain. Also good. Examples of the alicyclic structure include a cycloalkane structure and a cycloalkene structure, and a cycloalkane structure is preferable from the viewpoint of thermal stability. The number of carbon atoms constituting the alicyclic structure is usually in the range of 4 to 30, preferably 5 to 20, and more preferably 5 to 15. When the number of carbon atoms is within this range, a container having excellent heat resistance and transparency can be obtained, which is preferable. The proportion of the repeating unit having an alicyclic structure in the alicyclic structure-containing polymer resin may be appropriately selected according to the purpose of use, but is usually 50% by weight or more, preferably 70% by weight or more, more preferably. Is 90% by weight or more. It is preferable in terms of heat resistance that the ratio of the repeating unit having an alicyclic structure in the alicyclic structure-containing polymer resin is in this range. In addition, the remainder other than the repeating unit which has an alicyclic structure in an alicyclic structure containing polymer resin is suitably selected according to the intended purpose.

  Specific examples of the alicyclic structure-containing polymer resin include (1) norbornene polymer, (2) monocyclic olefin polymer, (3) cyclic conjugated diene polymer, and (4) vinyl alicycle. And a hydrocarbon compound of these formulas. Among these, from the viewpoints of heat resistance, mechanical strength, and the like, norbornene polymer hydrides, vinyl alicyclic hydrocarbon polymers, and hydrides thereof are preferable.

(1) Norbornene-based polymer The norbornene-based polymer used in the present invention includes a ring-opening polymer of a norbornene-based monomer, and a ring-opening copolymer of a norbornene-based monomer and another monomer capable of ring-opening copolymerization with this. And hydrides thereof; addition polymers of norbornene monomers, addition copolymers of norbornene monomers and other monomers copolymerizable therewith, and the like. Among these, from the viewpoints of heat resistance, mechanical strength, and the like, a ring-opening polymer hydride of a norbornene monomer is most preferable.

Examples of the norbornene-based monomer include bicyclo [2.2.1] hept-2-ene (common name: norbornene) and derivatives thereof (having a substituent in the ring), and tricyclo [4.3.1 ^2,5 . 0 ^1,6 ] deca-3,7-diene (common name dicyclopentadiene) and its derivatives, tetracyclo [7.4.1 ^10,13 . 0 ^1,9 . 0 ^2,7 ] trideca-2,4,6,11-tetraene (commonly used methanotetrahydrofluorene) and its derivatives, tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene (common name: tetracyclododecene) and its derivatives. Examples of the substituent include an alkyl group, an alkylene group, a vinyl group, and an alkoxycarbonyl group, and the norbornene-based monomer may have two or more of these. Specifically, 8-methoxycarbonyl group-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-methyl-8-methoxycarbonyl-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene and the like. These norbornene monomers are used alone or in combination of two or more.

Ring-opening polymers of these norbornene monomers, or ring-opening copolymers of norbornene monomers and other monomers capable of ring-opening copolymerization are polymerized in the presence of a known ring-opening polymerization catalyst. Can be obtained. Examples of the ring-opening polymerization catalyst include a catalyst comprising a metal halide such as ruthenium or osmium, a nitrate or an acetylacetone compound, and a reducing agent, or a metal halide or acetylacetone such as titanium, zirconium, tungsten, or molybdenum. A catalyst comprising a compound and an organoaluminum compound can be used.
Examples of other monomers capable of ring-opening copolymerization with norbornene monomers include monocyclic olefin monomers such as cyclohexene, cycloheptene, and cyclooctene.

  The ring-opening (co) polymer hydride of a norbornene-based monomer is usually obtained by adding a known hydrogenation catalyst containing a transition metal such as nickel or palladium to the polymerization solution of the ring-opening polymer, and carbon-carbon unsaturated. It can be obtained by hydrogenating the bond.

  Addition polymers of norbornene monomers, or addition copolymers of norbornene monomers and other monomers copolymerizable therewith, these monomers can be combined with known addition polymerization catalysts such as titanium, zirconium or vanadium compounds. It can be obtained by (co) polymerization using a catalyst comprising an organoaluminum compound.

  Examples of other monomers copolymerizable with the norbornene monomer include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1- C2-C20 alpha-olefins, such as hexadecene, 1-octadecene, 1-eicocene, and derivatives thereof; cyclobutene, cyclopentene, cyclohexene, cyclooctene, 3a, 5,6,7a-tetrahydro-4,7-methano Cycloolefins such as -1H-indene, and derivatives thereof; non-conjugated dienes such as 1,4-hexadiene, 4-methyl-1,4-hexadiene, 5-methyl-1,4-hexadiene, 1,7-octadiene Etc. are used. Among these, an α-olefin, particularly ethylene is preferable.

  These other monomers copolymerizable with the norbornene-based monomer can be used alone or in combination of two or more. In the case of addition copolymerization of a norbornene monomer and another monomer copolymerizable therewith, the ratio of the structural unit derived from the norbornene monomer and the structural unit derived from the other monomer copolymerizable in the addition copolymer However, it is appropriately selected so that the weight ratio is usually 30:70 to 99: 1, preferably 50:50 to 97: 3, and more preferably 70:30 to 95: 5.

(2) Monocyclic cyclic olefin polymer As the monocyclic olefin polymer, for example, an addition polymer of a monocyclic olefin monomer such as cyclohexene, cycloheptene, or cyclooctene can be used. .

(3) Cyclic conjugated diene polymer As the cyclic conjugated diene polymer, for example, a polymer obtained by subjecting a cyclic conjugated diene monomer such as cyclopentadiene or cyclohexadiene to 1,2- or 1,4-addition polymerization, and The hydride can be used.

  The molecular weight of the norbornene-based polymer, monocyclic olefin-based polymer or cyclic conjugated diene-based polymer used in the present invention is appropriately selected according to the purpose of use, but the cyclohexane solution (when the polymer resin does not dissolve) Is a weight average molecular weight in terms of polyisoprene or polystyrene measured by gel permeation chromatography of toluene solution, and is usually 5,000 to 500,000, preferably 8,000 to 200,000, more preferably 10, The range is from 000 to 100,000. When the weight average molecular weight is in this range, the mechanical strength and moldability of the container are highly balanced, which is preferable.

(4) Vinyl alicyclic hydrocarbon polymer Examples of the vinyl alicyclic hydrocarbon polymer include polymers of vinyl alicyclic hydrocarbon monomers such as vinyl cyclohexene and vinyl cyclohexane and their hydrides; , Hydrides of aromatic ring moieties of polymers of vinyl aromatic monomers such as α-methylstyrene; and the like, and vinyl alicyclic hydrocarbon polymers and vinyl aromatic monomers, and these Any of random copolymers with other monomers copolymerizable with monomers, copolymers such as block copolymers, and hydrides thereof may be used. Examples of the block copolymer include diblock, triblock, or more multiblock and gradient block copolymers, and are not particularly limited.

  The molecular weight of the vinyl alicyclic hydrocarbon polymer used in the present invention is appropriately selected according to the purpose of use, but is a gel permeation chromatograph of a cyclohexane solution (a toluene solution when the polymer resin does not dissolve). The weight average molecular weight in terms of polyisoprene or polystyrene measured by the method is usually in the range of 10,000 to 300,000, preferably 15,000 to 250,000, more preferably 20,000 to 200,000. When the weight average molecular weight is in this range, the mechanical strength and moldability of the container are highly balanced, which is preferable.

  The glass transition temperature (Tg) of the alicyclic structure-containing polymer resin used in the present invention may be appropriately selected according to the purpose of use, but is preferably 80 ° C or higher, and in the range of 100 to 250 ° C. More preferably, it is in the range of 120 to 200 ° C, particularly preferably in the range of 130 to 140 ° C. When Tg is within this range, heat resistance and molding processability are highly balanced, which is preferable.

In addition, various compounding agents can be mix | blended with the alicyclic structure containing polymer resin used for this invention as needed. Compounding agents include, for example, antioxidants, heat stabilizers, light stabilizers, weathering stabilizers, UV absorbers, near infrared absorbers and other stabilizers; lubricants, plasticizers and other resin modifiers; dyes and pigments And coloring agents such as antistatic agents. These compounding agents can be used alone or in combination of two or more, and the compounding amount is appropriately selected within a range not impairing the object of the present invention.
Examples of the antioxidant include phenol-based antioxidants, phosphorus-based antioxidants, sulfur-based antioxidants, etc. Among them, phenol-based antioxidants, particularly alkyl-substituted phenol-based antioxidants are preferable. By blending these antioxidants, it is possible to prevent the container from being colored or reduced in strength due to oxidative degradation during molding without lowering transparency or the like. These antioxidants may be used alone or in combination of two or more. Although the compounding quantity of antioxidant is suitably selected in the range which does not impair the objective of this invention, it is 0.001-5 weight part normally with respect to 100 weight part of alicyclic structure containing polymer resin, Preferably it is 0.00. 01 to 1 part by weight.

In addition, the alicyclic structure-containing polymer resin used in the present invention can be mixed with other types of polymers (rubber and resin) and used as a molding composition as a polymer composition.
Specifically, olefin polymers such as polyethylene and polypropylene; isobutylene polymers such as polyisobutylene and isobutylene / isoprene rubber; polybutadiene, polyisoprene, butadiene / styrene random copolymer, isoprene / styrene random copolymer, Acrylonitrile / butadiene copolymer, acrylonitrile / butadiene / styrene copolymer, butadiene / styrene / block copolymer, styrene / butadiene / styrene / block copolymer, isoprene / styrene / block copolymer, styrene / isoprene / styrene・ Diene polymers such as block copolymers; acrylic polymers such as polybutyl acrylate and polyhydroxyethyl methacrylate; polyvinyl alcohol, polyvinyl acetate, vinyl acetate Polymers of vinyl compounds such as ethylene copolymers; Epoxy polymers such as polyethylene oxide, polypropylene oxide and epichlorohydrin rubber; Fluoropolymers such as vinylidene fluoride rubber and tetrafluoroethylene-propylene rubber; It is done. These soft polymers may have a cross-linked structure or may have a functional group introduced by a modification reaction. Among the above polymers, diene polymers are preferable, and hydrides obtained by hydrogenating carbon-carbon unsaturated bonds of the polymer are particularly preferable in terms of rubber elasticity, mechanical strength, flexibility, and dispersibility.

(Blow molded container)
The method for producing a blow molded container comprising an alicyclic structure-containing polymer resin used in the present invention is not particularly limited, but is a hollow body having an opening by injection molding the alicyclic structure-containing polymer resin. A method of performing a step of forming a preform, a heating step of heating the obtained preform with a heating pot, and a blow molding step of inserting the heated preform into a blow mold and blowing air to blow are preferable.

[Preform molding process]
The cylinder temperature in the preform molding step is not particularly limited, but is preferably in the range of 150 to 400 ° C, more preferably in the range of 200 to 350 ° C, and particularly preferably in the range of 230 to 330 ° C. When the cylinder temperature is within this range, it is preferable in terms of non-distortion and colorlessness of the resulting container due to suppression of thermal decomposition and fluidity.
The diameter of the preform, the inner diameter of the hollow portion, and the length in the axial direction can be appropriately selected depending on the size of the intended container.

[Heating process]
The temperature of the heating pot is not particularly limited, but is preferably in the range of 200 to 700 ° C, more preferably in the range of 300 to 650 ° C, and particularly preferably in the range of 350 to 610 ° C. When the temperature of the heating pot is within this range, it is difficult for the blow molded container to be distorted.
The heating time is appropriately selected depending on the shape of the resin and the preform, but is preferably in the range of 5 to 20 seconds.
The preform temperature after heating is not particularly limited, but is preferably 180 ° C. or higher.

[Blow molding process]
The blow mold temperature is appropriately selected depending on the alicyclic structure-containing polymer resin to be used. When the glass transition temperature of the alicyclic structure-containing polymer resin to be used is Tg, (Tg-55 ° C.) to ( Tg + 20 ° C. is preferable, and (Tg−10 ° C.) to (Tg + 20 ° C.) is more preferable. When the blow mold temperature is within this range, the solvent crack resistance of the container is improved.
Although the draw ratio of blow molding is not particularly limited, the draw ratio y in the machine direction is preferably 0.9 or more, most preferably 1 or more and 1.35 or less, and the draw ratio in the transverse direction with respect to the draw ratio y in the machine direction. The ratio of x (x / y) is preferably from 1.25 to 1.9, and most preferably from 1.3 to 1.8. It is preferable in terms of solvent crack resistance that the longitudinal draw ratio y and the longitudinal / lateral stretch ratio (x / y) are in the above ranges.
In the present invention, the longitudinal stretch ratio (y) is the ratio of the length of the neck under the container (stretched portion) to the length of the preform neck (stretched portion). The draw ratio (x) is the ratio of the maximum horizontal diameter of the container to the maximum horizontal diameter of the preform.

The blow molding may be ordinary blow molding, but is preferably stretch blow using a stretch rod or the like.
The blow air introduced into the preform may be introduced from the mouth of the preform or may be introduced from a stretching rod.

The thickness of the blow molded container is usually 0.5 to 3 mm, preferably 0.7 to 2 mm. Examples of the shape of the container include a cylindrical shape, a prismatic shape, a spherical shape, and the like, and a cylindrical shape and a prismatic shape are preferable from the viewpoint of impact strength and the like.
Further, the shape may be a skirt spreading from the opening to the bottom, or a shape in which the center in the height direction is swollen.

Although the bottom shape of the blow molded container is not particularly limited, it is preferable that the upper bottom part is formed so as to protrude inward of the container, and an annular grounding part is formed on the outer periphery of the upper bottom part. It is preferable that the shape of the bottom is the above-mentioned shape because the annular grounding portion has a self-supporting property in the container and the upper bottom can prevent deformation due to the weight of the contents of the bottom.
The difference in height between the upper bottom portion and the ground contact portion in the bottom shape is not particularly limited, but the difference in height between the upper bottom portion and the ground contact portion is preferably in the range of 3 to 6 mm. If the difference in height between the upper base and the grounding portion is within this range, it is preferable in terms of the drop strength of the container.

  The blow-molded container has a mouth part and a body part that can be attached with a lid so that medicines, foods, etc. can be stored in a hermetically sealed state, and can be treated with steam sterilization in a state where the medicines, foods, etc. are kept in a hermetically sealed state. It is preferable to have a shape. The mouth portion preferably has a screw groove, an uneven portion that can be fitted to the lid, and the like so that the lid can be attached and sealed.

(Urethane transparent ink)
Examples of the urethane-based transparent ink used in the present invention include two-component urethane resin ink, block-type polyurethane resin ink, moisture-curable polyurethane resin ink, and oil-modified polyurethane resin ink.
Among these, a two-component urethane resin ink is preferable in terms of adhesion to an alicyclic structure-containing polymer resin, chemical resistance, and abrasion resistance.
The two-component urethane resin ink is composed of a polyol composition and an isocyanate curing agent. Examples of the polyol composition include polyether polyols, polyester polyols, acrylic polyols, and epoxy polyols, and examples of the isocyanate curing agent include polyhydric alcohols. And a prepolymer obtained by reacting an excess of toluene diisocyanate with a polyhydric alcohol, a prepolymer obtained by reacting an excess of xylene diisocyanate with a polyhydric alcohol, and a prepolymer obtained by reacting an excess of lysine isocyanate with a polyhydric alcohol.

(printing)
The method for printing the urethane-based transparent ink is not particularly limited, and examples thereof include silk screen printing, pad printing, and offset printing. Among these, silk screen printing is preferable in terms of the thickness of the printing layer.

In the present invention, it is preferable to perform a surface treatment before printing. Examples of the surface treatment method include corona discharge treatment, primer treatment, solvent treatment, and the like, but flame treatment is preferred from the viewpoint of adhesion between the ink and the alicyclic structure-containing polymer resin.
In addition, the blow molded container for heating according to the present invention may be further printed on the outer surface thereof after the urethane transparent ink is printed.

  The blow molded container of the present invention is excellent in solvent crack resistance, and since whitening does not occur even when steam sterilization is repeated in a state where sebum adheres, such as pharmaceutical containers, cosmetic containers, food containers, etc. Suitable as a container for heat treatment.

  Examples of the drug container include liquid and powdery drug containers, specifically, an infusion container and an infusion kit container; an eye drop container; a pure water container; a sampling tube for blood analysis; Blood collection tubes; Sample containers; Analytical containers such as UV test cells; Sterilization containers for medical instruments such as scalpels, candies, gauze, and contact lenses; Medical devices such as disposable syringes and prefilled syringes; beakers, vials, ampoules, test tubes, Laboratory instruments such as flasks; artificial organ housings and the like. Among these, a chemical container that is sterilized after being filled with a chemical or the like is more preferable. Specific examples include containers for sterile preparations that are required to maintain a high degree of sterility and containers for diagnostic reagents such as contrast media.

  Food containers include food storage containers, bottles of soft drinks, etc., but especially as food containers to which oil from sebum, saliva, etc. easily adheres, such as tableware, baby bottles, mugs, etc. Among them, it is most preferable as a container for microwave steam sterilization in which microwave steam sterilization is frequently performed with sebum attached.

  Hereinafter, although a manufacture example, an Example, and a comparative example are given and this invention is demonstrated more concretely, the scope of the present invention is not limited to these examples. In these examples, parts are by weight unless otherwise specified. Moreover, the measuring method of various physical properties is as follows.

(1) The glass transition temperature (Tg) was measured with a differential scanning calorimeter (DSC method).
(2) Unless otherwise specified, the molecular weight was measured as a polyisoprene equivalent value measured by gel permeation chromatography (GPC) using cyclohexane as a solvent.
(3) n-heptane impregnation test (solvent crack resistance)
Add 2.5 L of n-heptane (Wako Pure Chemical Industries, Ltd.) to a 3 L glass beaker. The measurement sample container is immersed in n-heptane in the glass beaker. Observe the whitening state of the measurement sample container surface and the presence or absence of rupture after 10 minutes of immersion.
(4) Sebum whitening resistance test Hand sebum is adhered to the entire surface of the measurement sample container. The measurement sample container is set in a baby bottle disinfector for microwave oven (manufactured by Lec Co., Ltd., a baby bottle disinfector for DC microwave oven). About 60 ml of tap water is added into the baby bottle sterilizer for microwave oven. Next, a microwave bottle disinfector equipped with a measurement sample container is installed in the microwave and heated. The heat treatment time is 3 minutes. A general household device was used as the microwave oven (manufactured by SHARP, RE-50, rated voltage: 100 V, rated high frequency output: 500 W, oscillation frequency: 2450 MHz). After the heat treatment, the measurement sample container is taken out, washed with tap water, water droplets are wiped off with a soft nonwoven fabric on the surface, and the surface whitening state of the measurement sample container is observed. If not whitened or if the degree of whitening is slight, attach sebum on the entire surface of the measurement sample container again and repeat this test until the surface whitening of the measurement sample container is observed. Check the number of tests.

[Production Example 1]
In a nitrogen atmosphere, 500 parts of dehydrated cyclohexane, 0.82 part of 1-hexene, 0.15 part of dibutyl ether and 0.30 part of triisobutylaluminum were mixed in a reactor at room temperature, and then kept at 45 ° C. 80 parts of tricyclo [4.3.0.1 ^2,5 ] deca-3,7-diene (dicyclopentadiene, hereinafter abbreviated as DCP), 1,4-methano-1,4,4a, 9a-tetrahydrofluorene (Hereinafter abbreviated as MTF) 50 parts, and tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodeca-3-ene (hereinafter abbreviated as TCD) 70 parts of a norbornene monomer mixture and 40 parts of tungsten hexachloride (0.7% toluene solution) continuously over 2 hours. Added and polymerized. To the polymerization solution, 1.06 part of butyl glycidyl ether and 0.52 part of isopropyl alcohol were added to deactivate the polymerization catalyst and stop the polymerization reaction. When the copolymerization ratio of each norbornene monomer in the polymer was calculated from the composition of residual norbornenes in the solution after polymerization (by gas chromatography method), it was almost charged at DCP / MTF / TCD = 40/25/35. It was equal to the composition.

  Next, 270 parts of cyclohexane is added to 100 parts of the reaction solution containing the obtained ring-opening polymer, and 5 parts of a nickel-alumina catalyst (manufactured by JGC Chemical Co., Ltd.) is added as a hydrogenation catalyst. The pressure was raised to 5 MPaG and the mixture was heated to 200 ° C. with stirring and reacted for 4 hours to obtain a reaction solution containing 20% of DCP / MTF / TCD ring-opening polymer hydride. After removing the hydrogenation catalyst from the obtained reaction solution by filtration, a soft polymer (Kuraray, Septon 2002) and an antioxidant (Ciba Specialty Chemicals, Irganox 1010) are added and dissolved. (Both 0.1 parts per 100 parts polymer). Next, the solvent, cyclohexane and other volatile components, are removed from the solution using a cylindrical concentrating dryer (manufactured by Hitachi, Ltd.), and the polymer hydride is extruded into a strand form from an extruder. It was cut with a cutter, pelletized, and collected. This ring-opening polymer hydrogenated product had a weight average molecular weight (Mw) of 35,000, a hydrogenation rate of 99.9%, and a Tg of 134 ° C.

  The pellet obtained in Production Example 1 was dried at 100 ° C. for 2 hours using a hot air dryer in which air was circulated, and then the cylinder temperature was 285 ° C. using an injection stretch blow molding machine (manufactured by Nissei ASB Machine Industries). The preform was molded under the conditions of a hot runner temperature of 285 ° C. and a preform mold temperature of 120 ° C. Next, the preform was heated under the conditions of a heating pot of 390 ° C. and a heating time of 11 seconds using a heating device provided with a heating pot installed so that the distance from the preform was 5 mm. Next, blow molding was performed while blowing air into the preform under a blow mold temperature of 130 ° C. to obtain a container having a neck portion having an opening and a body portion.

[Comparative Example 1]
Using the container obtained in Production Example 1, an n-heptane impregnation test and a sebum whitening resistance test were performed. As a result, whitening was confirmed in the lower part in the n-heptane impregnation test, and whitening was confirmed in the lower part in 5 cycles in the sebum whitening resistance test.

[Example 1]
Using the frame processing device (manufactured by Shinei Kogyo Co., Ltd .; SK-66-S2 type frame processing machine) on the outer surface of the container obtained in Production Example 1, the distance between the burner nozzle and the sample is 100 mm, and the moving speed of the conveyor The frame processing was performed under the conditions of 13 m / min, sequential stop time of 0.5 seconds, and sample rotation speed of 465 rpm.
Next, a two-component urethane resin transparent ink (manufactured by Seiko Advance, SG740 (N), 800 medium, curing agent SG740, diluent T-926) was printed by a silk screen printing method. The liquid mixture of the transparent ink was prepared by mixing and stirring so that ink / curing agent / diluent = 100/10/20 (weight ratio).
After printing, for the ink layer curing treatment, a drying treatment at 80 ° C. for 30 minutes was performed in an oven.
Using the container after the drying treatment, an n-heptane impregnation test and a sebum whitening resistance test were performed. As a result, in the n-heptane impregnation test, whitening was not confirmed, and in the sebum whitening resistance test, whitening was not confirmed even in 10 cycles, so the test was terminated.
[Comparative Example 2]
Instead of the two-component urethane resin transparent ink, printing was performed in the same manner as in Example 1 except that a UV-curable epoxy acrylate-based transparent ink (Seiko Advance, HUG9031) was used, and then UV curing (conditions 2 lamps of 80 W / cm metal halide lamp, lamp height of 15 cm, belt speed of 10 m / min) to obtain a container, but the test was stopped because the printed surface was peeled off during the sebum whitening resistance test.

These results show the following.
A container formed by blow-molding an alicyclic structure-containing polymer resin, and a blow-molded container for heating formed by printing urethane-based transparent ink on at least a part of the surface has excellent printing adhesion and resistance. It is excellent in solvent cracking property and sebum whitening resistance (Example 1).
On the other hand, the blow-molded container for heating which is not printed is inferior in solvent crack resistance and sebum whitening resistance (Comparative Example 1).
Further, when the ink was not a urethane-based transparent ink, the printing surface was peeled off and the adhesion between the container and the printing layer was poor (Comparative Example 2).

  The blow-molded container for heating of the present invention has excellent solvent crack resistance, and does not cause deformation or whitening even when steam sterilized with a microwave oven in a state where sebum is attached, so that baby bottles, cosmetic containers, pharmaceuticals It is suitable as a container for performing heat treatment such as a container.

Claims (5)

A blow molding container for heating, which is a container formed by blow molding an alicyclic structure-containing polymer resin, wherein urethane transparent ink is printed on at least a part of the outer surface. The blow-molded container for heating according to claim 1, wherein the urethane-based transparent ink is a two-component urethane resin ink. The blow-molded container for heating according to claim 1 or 2, wherein the blow-molded container is a baby bottle. The blow-molded container for heating according to claim 3, wherein the baby bottle is a baby bottle for microwave steam sterilization. 6. The heating device according to claim 1, wherein the outer surface of a blow molded container comprising an alicyclic structure-containing polymer resin is subjected to a frame treatment, and then urethane-based transparent ink is silk-screen printed on at least a part of the outer surface. Blow molded container manufacturing method.