JPH10215720A - Animal breeding casing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an animal breeding casing which is transparent, excellent in heat resistance, chemical resistance, and shock resistance and excellent in the easily cleanability of animal excreta. SOLUTION: This animal breeding casing obtained by molding from a molding material consisting of cyclic olefin resin is transparent, excellent in heat resistance, chemical resistance, and shock resistance and excellent in the easily cleanability as animal excreta is difficult to stuck to it. The casing is obtained by molding a molding material consisting of cyclic olefin resin of not lower than 100 deg.C glass transition temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a container for breeding animals, and more particularly, to a container having high transparency, excellent visibility of contents, easy cleaning of animal excrement, and chemical resistance to various chemicals. The present invention relates to an animal breeding container having excellent heat resistance and impact resistance.

[0002]

2. Description of the Related Art Conventionally, mammals such as rats and small rabbits,
Containers for raising amphibians such as snakes, frogs, turtles and lizards for pets or for mammals such as mice, rats and guinea pigs for laboratory use include metal nets, metal baskets, metal plates, glass, A transparent or opaque thermoplastic resin is used as a material. Among these materials, the weight of the container for transportation is light, the inside of the container is transparent and can be confirmed, mass production is possible, and it is difficult to deform or break even if it is handled violently by dropping it etc. Therefore, a transparent thermoplastic resin has been preferably used.

[0003] In particular, in the case of breeding containers for small experimental animals, it is necessary to wash them with warm water or to frequently sterilize them in order to prevent infection of animals with pathogenic bacteria. When washing with warm water,
Animal breeding containers are required to have heat resistance enough to withstand washing with hot water at a maximum of 100 ° C. In addition, when performing sterilization such as alcohol sterilization and steam sterilization, high heat resistance and chemical resistance are required. In particular, in the case of steam sterilization, an autoclave autoclave is used.
Under pressure of 5 to 2.5 atm, usually about 2 atm (in this case, the temperature is about 121 ° C.), for 10 to 60 minutes,
Usually, it is carried out by holding for about 20 to 30 minutes, so that the animal breeding container is required to have particularly high heat resistance.

Conventionally, polycarbonate resins and polysulfone resins have been used as thermoplastic resin materials for molding animal breeding containers because they are transparent and have excellent heat resistance. However, there has been a problem that polycarbonate resin and polysulfone resin elute acidic components by steam sterilization, or cause solvent cracks due to alcohol or other chemicals used in animal experiments, causing the container to be broken or cracked.

In addition, these thermoplastic resin materials have a problem that feces and urine, which are excretions of animals to be bred, tend to adhere to both containers for pets and small experimental animals, and are difficult to wash. In particular, in the case of a container for a small laboratory animal, there is a problem that various bacteria are easily generated in the trace, which hinders the original purpose of the animal experiment.

On the other hand, as a resin having excellent transparency and heat resistance, a cyclic olefin resin has been proposed, and a molded article formed of a molding material comprising the resin is transparent, has good chemical resistance, and has a high vapor resistance. It is known that it is not deformed by sterilization, is not attacked by various chemicals such as acids and alkalis, and has a small amount of eluted substances.It is known that it is mainly used for disposable or short-term use in medical applications. Had been. However, it is not known whether there is little adhesion of excrement and the resulting denaturation, and whether the molded article will be degraded after long-term use as an animal breeding container. It was impossible.

[0007]

An object of the present invention is to provide an animal breeding container which is transparent, excellent in heat resistance, chemical resistance and impact resistance, and excellent in facilitating washing of animal excrement. Is to provide.

[0008]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems of the prior art, and as a result, the animal breeding container formed of a molding material made of a cyclic olefin resin is transparent, It has been found that it is excellent in heat resistance and chemical resistance, and hardly adheres to animal excrement, and is also excellent in cleanability. The present invention has been completed based on these findings.

Thus, according to the present invention, there is provided an animal breeding container formed by molding a molding material comprising a cyclic olefin resin having a glass transition temperature of 100 ° C. or higher.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION

(Cyclic Olefin Resin) The cyclic olefin resin used in the present invention is an amorphous and transparent resin having a hydrocarbon ring structure in the main chain or side chain of the polymer. A typical example is a thermoplastic norbornene-based resin. The thermoplastic norbornene-based resin is a known resin disclosed in JP-A-3-14882 and JP-A-3-122137, and specifically, a ring-opened polymer of a norbornene-based monomer and a hydrogen-opening polymer thereof. Additives, addition polymers of norbornene-based monomers, addition copolymers of vinyl compounds copolymerizable with norbornene-based monomers, and modified products of these polymers are exemplified. Among these, hydrogenated ring-opening polymers of norbornene monomers, addition polymers of norbornene monomers, addition copolymers of vinyl compounds copolymerizable with norbornene monomers, and the like are preferred. Hydrogenated cyclic polymers are particularly preferred because transparency, heat resistance and ease of excrement cleaning are highly balanced. Other resins include addition polymers of cyclic olefins and cyclic dienes and hydrogenated products thereof disclosed in JP-A-6-13657 and JP-A-7-258362.

The norbornene monomers are disclosed in the above publications, JP-A-2-227424 and JP-A-2-27684.
A known monomer disclosed in, for example, Japanese Patent Publication No. 2 (November 2), for example, a polycyclic hydrocarbon having a norbornene structure;
Derivatives substituted with hydrocarbon groups such as alkyl, alkenyl, alkylidene and aryl; Derivatives substituted with polar groups such as halogen, hydroxyl group, ester group, alkoxy group, cyano group, amide group, imide group and silyl group; alkyls having these polar groups , Alkenyl, alkylidene, aryl and the like hydrocarbon-substituted derivatives; and the like. Among them, polycyclic hydrocarbons having a norbornene structure and substituted derivatives thereof such as alkyl, alkenyl, alkylidene, and aryl are preferable because they are excellent in chemical resistance and hardly adhere to excrement and are also excellent in easy cleaning. . Further, in the case of a norbornene-based monomer having a plurality of carbon-carbon unsaturated bonds in one molecule, a part of the plurality of carbon-carbon unsaturated bonds is saturated by a technique such as hydrogenation, and one Alternatively, it may be used as a norbornene-based monomer having a reduced number of carbon-carbon unsaturated bonds compared to before the saturation reaction.

Specific examples of the norbornene-based monomer include, for example, 5-methyl-2-norbornene (bicyclic,
Hereinafter, a monomer having n hydrocarbon rings other than an aromatic ring in a molecule is referred to as an n-ring)), 5,5-dimethyl-
2-norbornene (bicyclic), 5-ethyl-2-norbornene, 5-butyl-2-norbornene (bicyclic), 5
-Ethylidene-2-norbornene, 5-methoxycarbonyl-2-norbornene (bicyclic), 5-cyano-2-
Norbornene, 5-methyl-5-methoxycarbonyl-
2-norbornene (bicyclic), 5-phenyl-2-norbornene (bicyclic), 5-phenyl-5-methyl-2-
Norbornene (bicyclic) and the like; dimethanooctahydronaphthalene (tetracyclic) and the same substituted derivatives thereof as described above, for example, 6-methyl-1,4: 5,8-dimethano-1,
4,4a, 5,6,7,8,8a-octahydronaphthalene (tetracyclic), 6-ethyl-1,4: 5,8-dimetano-1,4,4a, 5,6,7,8 , 8a-Octahydronaphthalene (tetracyclic), 6-ethylidene-1,4:
5,8-Dimethano-1,4,4a, 5,6,7,8,8
a-octahydronaphthalene (tetracyclic), 6-chloro-
1,4: 5,8-dimethano-1,4,4a, 5,6
7,8,8a-octahydronaphthalene (tetracyclic), 6
-Cyano-1,4: 5,8-dimethano-1,4,4a,
5,6,7,8,8a-octahydronaphthalene (tetracyclic), 6-pyridyl-1,4: 5,8-dimethano-1,
4,4a, 5,6,7,8,8a-octahydronaphthalene (tetracyclic), 6-methoxycarbonyl-1,4:
5,8-Dimethano-1,4,4a, 5,6,7,8,8
a-octahydronaphthalene (tetracyclic) or the like and substituted derivatives thereof as described above; adducts of cyclopentadiene and tetrahydroindene (pentacyclic), substituted derivatives thereof as described above, for example, 1, 4-dimethano-1,4
4a, 4b, 5,8,8a, 9a-octahydrofluorene (pentacyclic), 5,8-methano-1,2,3,4,4
a, 5,8,8a-Octahydro-2,3-cyclopentadienonaphthalene etc. (pentacyclic); cyclopentadiene multimers (tricyclic, pentacyclic, heptacyclic, etc.), similar to the above Or a hydrogenated product thereof, for example, dicyclopentadiene (tricyclic), 2,3-dihydrodicyclopentadiene (tricyclic), 4,9: 5,8-
Dimethano-3a, 4,4a, 5,8,8a, 9,9a-
Octahydro-1H-benzoindene (pentacyclic) and the like.

These norbornene monomers can be used alone or in combination of two or more. However, of the total amount of these monomers, from the viewpoint of high heat resistance required for animal breeding containers, It is preferable to use at least 50% by weight of a monomer having four or more rings or a monomer having two or more rings and having an aromatic ring.

The vinyl compounds copolymerizable with these norbornene monomers include, for example, ethylene, propylene, 1-butene, 1-pentene, 1-hexene,
-Methyl-1-butene, 3-methyl-1-pentene, 3
-Ethyl-1-pentene, 4-methyl-1-pentene,
4-methyl-1-hexene, 4,4-dimethyl-1-hexene, 4,4-dimethyl-1-pentene, 4-ethyl-1-hexene, 3-ethyl-1-hexene, 1-octene, 1- Decene, 1-dodecene, 1-tetradecene,
C2-C20 ethylene or α-olefin such as 1-hexadecene, 1-octadecene, 1-eicosene; cyclobutene, cyclopentene, cyclohexene,
Cycloolefins such as 3,4-dimethylcyclopentene, 3-methylcyclohexene, 2- (2-methylbutyl) -1-cyclohexene, cyclooctene, 3a, 5,6,7a-tetrahydro-4,7-methano-1H-indene 1,4-hexadiene, 4-methyl-1,4-
Hexadiene, 5-methyl-1,4-hexadiene,
Non-conjugated dienes such as 1,7-octadiene; and the like. These copolymerizable vinyl compounds can be used alone or in combination of two or more.

As the cyclic olefin, cyclobutene,
1-methylcyclopentene, 3-methylcyclobutene,
Monocyclic cycloolefins such as 3,4-diisopropenylcyclobutene, cyclopentene, 3-methylcyclopentene, cyclohexene, cyclooctene, 1-methylcyclooctene, 5-methylcyclooctene, cyclooctatetraene, cyclododecene, and the above-mentioned norbornene Among the monomers having a ring, those having one unsaturated bond can be mentioned.

Examples of the cyclic diene include monocyclic dienes such as cyclopentadiene, 1,3-cyclohexadiene and 1,4-cyclohexadiene, and those having two unsaturated bonds among the above-mentioned monomers having a norbornene ring. be able to.

Further, in both the ring-opening polymerization and the addition polymerization, various copolymerizable monomers may be copolymerized in the respective catalyst systems to be polymerized. Examples of the copolymerizable monomer include, in addition to the above-mentioned monomer having a norbornene ring, α-olefin, cyclic olefin, and cyclic diene, linear or branched dienes such as butadiene and isoprene. The polymerization may be random, block type, or alternating type, and when addition polymerization involves 1,2-addition and 1,4-addition, either one may be the main.

When unsaturated bonds remain in the polymer after polymerization,
In other words, in the case of a ring-opened polymer of a monomer having a norbornene ring or an addition polymer of a cyclic diene, the weather resistance and thermal stability of the polymer are reduced due to the remaining unsaturated bonds. For the purpose of hydrogenation, 80% or more, preferably 9% of unsaturated bonds
It is preferable that 0% or more be used after being saturated. The hydrogenation method and the hydrogenation catalyst can be performed by a known method.

The proportion of the norbornene monomer unit in the cyclic olefin resin is appropriately selected according to the purpose of use, but is usually at least 30% by weight, preferably at least 50% by weight.
More preferably 70% by weight or more has transparency,
Physical properties such as heat resistance are highly balanced and suitable.

The molecular weight of the cyclic olefin resin is appropriately selected according to the purpose of use, but is usually 0.01 to 20 dl / g as the intrinsic viscosity [η] measured in decalin at 80 ° C.
Preferably 0.1 to 10 dl / g, more preferably 0.1 to 10 dl / g
It is in the range of 2-5 dl / g, most preferably 0.3-1 dl / g. When the intrinsic viscosity [η] of the cyclic olefin resin is in this range, it is preferable because mechanical strength such as impact resistance and molding workability are excellent.

The glass transition temperature of the cyclic olefin resin (T
g) may be appropriately selected depending on the purpose of use, but is usually in the range of 100 to 375 ° C, preferably 125 to 350 ° C. The higher the Tg, the higher the heat resistance, which is the temperature at which the animal breeding container can withstand deformation due to heating, and it is preferable because it does not deform even when applied to hot water treatment, steam sterilization, or the like. In particular, when the Tg is 125 ° C. or higher, steam sterilization is possible, which is particularly preferable. If the Tg is higher than the preferred range, the temperature for heating the molding material during molding becomes higher, which may cause difficulty in processing.

These cyclic olefin resins can be used alone or in combination of two or more.

(Other polymer components) In addition to the cyclic olefin resin, other polymer components can be added to the molding material used in the present invention, if necessary. Other polymer components include rubbery polymers and thermoplastic resins other than cyclic olefin resins. Among these, rubbery polymers are preferred because they can significantly reduce the decrease in transparency due to repeated steam sterilization.

The rubbery polymer is preferably a rubbery polymer having a glass transition temperature of about room temperature or lower, specifically 40 ° C. or lower.
In addition, there are cases where the glass transition temperature of a block copolymerized rubbery polymer or the like is 2 or more. In this case, if the lowest glass transition temperature is 40 ° C or lower, the glass transition temperature of the present invention is 40 ° C. It can be used as the following rubbery polymer.

A thermoplastic resin other than the cyclic olefin resin may be used in combination. Examples of such thermoplastic resins include polyolefins such as low-density polyethylene, high-density polyethylene, linear low-density polyethylene, ultra-low-density polyethylene, polypropylene, syndiotactic polypropylene, polybutene, and polypentene; polyethylene terephthalate, polybutylene Polyesters such as terephthalate; polyamides such as nylon 6 and nylon 66; ethylene-ethyl acrylate copolymer, ethylene-vinyl acetate copolymer, polystyrene, syndiotactic polystyrene, polyphenylene sulfide, polyphenylene ether, polyamide,
Examples include polyester and polycarbonate. These other thermoplastic resins can be used alone or in combination of two or more, and the blending amount is appropriately selected within a range not to impair the object of the present invention.

Examples of preferred rubbery polymers as other polymer components include natural rubber, polybutadiene rubber, polyisoprene rubber, hydrogenated products thereof; chloroprene rubber, hydrogenated products thereof, and ethylene such as ethylene-propylene copolymer. Saturated polyolefin rubbers such as α-olefin copolymers, propylene and other α-olefin copolymers; ethylene-propylene-diene copolymers, α-olefin-diene copolymers, isobutylene
Α-olefin / diene copolymers such as isoprene copolymer and isobutylene / diene copolymer, and halides thereof; acrylonitrile / butadiene copolymer, hydrogenated products thereof; vinylidene fluoride / ethylene trifluoride copolymer; Vinylidene fluoride / propylene hexafluoride copolymer,
Fluorine rubber such as vinylidene fluoride / propylene hexafluoride / ethylene tetrafluoride copolymer, propylene / tetrafluoroethylene copolymer; urethane rubber, silicone rubber, polyether rubber, acrylic rubber, chlorosulfonated polyethylene rubber , Special rubbers such as epichlorohydrin rubber, propylene oxide rubber, and ethylene acrylic rubber; copolymers of norbornene monomers and ethylene or α-olefins, norbornene monomers and ethylene and α
-Norbornene-based rubbery polymers such as olefin terpolymers; styrene / butadiene copolymer rubber, styrene / isoprene copolymer rubber, styrene / butadiene /
Random copolymers of aromatic vinyl monomers and conjugated dienes such as isoprene terpolymer rubbers and hydrogenated products thereof, styrene / butadiene / styrene block copolymer rubber, styrene / isoprene / styrene block copolymer Styrene-based thermoplastic elastomers such as linear or radial block copolymers of aromatic vinyl-based monomers and conjugated dienes such as rubber, and hydrogenated products thereof;
A thermoplastic elastomer such as a urethane-based thermoplastic elastomer; a polyamide-based thermoplastic elastomer; a 1,2-polybutadiene-based thermoplastic elastomer; a vinyl chloride-based thermoplastic elastomer; and a fluorine-based thermoplastic elastomer.

The rubbery polymer is preferably one having a small difference in refractive index from the cyclic olefin resin, or one that easily disperses by taking microdomains when mixed with the cyclic olefin resin. In combination with a cyclic olefin resin.

In order to maintain high transparency even when the added amount of the rubbery polymer is large, the smaller the difference in the refractive index between the rubbery polymer and the cyclic olefin resin, the better the transparency and the better. Particularly when the compounding amount is large, it is preferable to use a compounding agent having a small refractive index difference, and in that case, the refractive index difference is usually 0.2 or less, preferably 0.1 or less, more preferably 0.05 or less. Preferably it is 0.02 or less.
Different types of cyclic olefin resins have different refractive indices.For example, rubbery polymers continuously change the monomer ratio or change the number of unsaturated bonds in the main chain by hydrogenation or the like. It is possible to change the refractive index. Depending on the refractive index of the cyclic olefin resin used,
It is preferable to select a rubbery polymer having an appropriate refractive index.

Among the above rubber polymers, a copolymer of an aromatic vinyl monomer and a conjugated diene monomer, a hydrogenated product thereof, and a norbornene rubber polymer have good dispersibility in a cyclic olefin resin. It is preferable because a resin having a refractive index close to that of the cyclic olefin resin can be selected. Here, the copolymer of the aromatic vinyl monomer and the conjugated diene monomer may be a block copolymer or a random copolymer. Preferred specific examples include styrene / butadiene block copolymer, styrene / butadiene / styrene / block copolymer, styrene / isoprene / block copolymer, styrene / isoprene / styrene / block copolymer, styrene / butadiene -A random copolymer and a hydrogenated product thereof are exemplified. Among them, when the animal breeding container is used for a long time, part or all of the carbon-carbon unsaturated bonds other than the aromatic ring from the viewpoint that contamination from excrement and deterioration in transparency due to weather resistance are small. More preferably, hydrogenated styrene / butadiene block copolymer, hydrogenated styrene / butadiene / styrene / block copolymer, hydrogenated styrene / isoprene / block copolymer Particularly, hydrogenated products of styrene / isoprene / styrene / block copolymers and hydrogenated products of styrene / butadiene / random copolymers are particularly preferable.

These rubbery polymers can be used alone or in combination. The amount of the rubbery polymer is usually 0.01 to 30 parts by weight, preferably 0.05 to 20 parts by weight, more preferably 0.10 parts by weight, based on 100 parts by weight of the cyclic olefin resin.
To 10 parts by weight. In particular, when the animal breeding container of the present invention is used after repeated steam sterilization, the compounding amount of the rubbery polymer is usually 0.05 to 3.00 parts by weight, preferably 0.2 to 2.00 parts by weight. Parts by weight, using a molding material containing 0.3 to 1.50 parts by weight is preferable because transparency at the initial stage before use is good, and transparency is hardly reduced by repeated steam sterilization. It is.

(Blending agent) The molding material used in the present invention may be blended with a blending agent generally used for synthetic resins as long as the object of the present invention is not impaired.

In order to further improve the effect of preventing the decrease in transparency during steam sterilization, etherified polyhydric alcohol or esterified polyhydric alcohol may be added to the cyclic olefin resin. Specifically, for example, glycerin monostearate, glycerin monolaurate, glycerin monobehenate, diglycerin monostearate, glycerin distearate, glycerin dilaurate, pentaerythritol monostearate known in JP-A-63-275654 , Pentaerythritol monolaurate, pentaerythritol monobeherate,
Etherified products of polyhydric alcohols such as pentaerythritol distearate, pentaerythritol dilaurate, pentaerythritol tristearate, dipentaerythritol distearate; 3- (octyloxy) -1,2-propanediol, 3- (decyloxy) -1,2-propanediol, 3- (lauryloxy) -1,2-propanediol, 3- (4-nonylphenyloxy) -purification, 2-propanediol, 1,6
-Dihydroxy-2,2-di (hydroxymethyl) -7
-(4-nonylphenyloxy) -4-oxoheptane, an ether compound obtained by reacting a condensate of p-nonylphenol and formaldehyde with glycidol,
an ether compound obtained by reacting a condensate of p-octylphenol and formaldehyde with glycidol, p
Esterified products of polyhydric alcohols such as ether compounds obtained by the reaction of glycidol with a condensate of octylphenol and dicyclopentadiene.

The molecular weight of the etherified product or esterified product of these polyhydric alcohols is not particularly limited.
Those having a molecular weight of from 00 to 2000, preferably from 800 to 1500 are preferable because they are hardly eluted and a decrease in transparency is small. These etherified or esterified polyhydric alcohols may be used alone or in combination of two or more. The compounding amount is usually 0.01 to 5 parts by weight, preferably 100 parts by weight of the cyclic olefin resin. 0.05
To 2 parts by weight, particularly preferably 0.1 to 1.0 part by weight. When the amount of addition is in this range, the effect of decreasing transparency and reducing elution in steam sterilization can be highly balanced.

It is also preferable to use a rubbery polymer in combination with an etherified or esterified product of a polyhydric alcohol. In this case, the effect of reducing transparency and reducing elution in steam sterilization can be more highly balanced.

A lubricant may be used for the purpose of improving moldability such as mold release. As the lubricant, for example, inorganic fine particles can be used. Here, the inorganic fine particles refer to the first, second, fourth, sixth, seventh, and seventh groups of the long period table.
Oxides, hydroxides, sulfides, nitrides, halides, carbonates, sulfates, acetates, phosphates, phosphites of Group 8 to 10, Group 11, Group 12, Group 13 and Group 14 elements; Organic carboxylate, silicate, titanate, particulates such as borate, these compounds and particulates of hydrous compounds of salts,
Particles of complex compounds having these salt centers or particles of natural minerals containing these salts as main components are shown. Specifically, Group 1 element compounds such as thylium fluoride, borax (sodium borate hydrate), magnesium carbonate,
Magnesium phosphate, magnesium oxide (magnesia),
Magnesium chloride, magnesium acetate, magnesium fluoride, magnesium titanate, magnesium silicate, magnesium silicate hydrate (talc), calcium carbonate, calcium phosphate, calcium phosphite, calcium sulfate (gypsum),
Calcium acetate, calcium terephthalate, calcium hydroxide, calcium silicate, calcium fluoride, calcium titanate, strontium titanate, barium titanate, zinc titanate, lanthanum titanate, bismuth titanate, lead titanate, barium carbonate, phosphoric acid Group 2 element compounds such as barium, barium sulfate and barium phosphite; Group 4 element compounds such as titanium dioxide (titania), titanium monoxide, titanium nitride, zirconium dioxide (zirconia), and zirconium monoxide; molybdenum dioxide; molybdenum trioxide Group 6 element compound such as molybdenum sulfide, group 7 element compound such as manganese chloride and manganese acetate, group 8 to 10 element compound such as cobalt chloride and cobalt acetate, group 11 element compound such as cuprous iodide, zinc oxide Group 12 element compounds such as zinc and zinc acetate Aluminum oxide (alumina),
Group 13 element compounds such as aluminum hydroxide, aluminum fluoride, aluminosilicate (alumina silicate, kaolin, kaolinite), silicon oxide (silica, silica gel), graphite, carbon, graphite, glass, etc.
Group 4 element compounds, and particles such as kernalite, kainite, mica (mica, kinunmo), and virose ore, which are natural favourites containing these compounds as main components, are exemplified. The average particle size of the inorganic fine particles used here is not particularly limited, but is preferably in the range of 0.01 to 3 μm. These lubricants can be used alone or in combination of two or more. The amount of the lubricant to be added is appropriately selected according to the purpose of use, but is usually 0.001 to 5 parts by weight, preferably 0.
When the amount is within this range, the transparency of the animal breeding container and the moldability during molding thereof are highly balanced.

It is preferable to use an antioxidant for the purpose of preventing oxidation and storage during molding, and oxidative deterioration and aging deterioration during long-term use. Examples of the antioxidant include a phenolic antioxidant, a phosphorus-based antioxidant, and a sulfur-based antioxidant. Among them, a phenol-based antioxidant is preferable, and an alkyl-substituted phenol-based antioxidant is preferable. Particularly preferred.

As the phenolic antioxidant, conventionally known phenolic antioxidants, for example, 2-t-butyl-6-
(3-t-butyl-2-hydroxy-5-methylbenzyl) -4-methylphenyl acrylate, 2,4-di-t-amyl-6- (1- (3,5-di-t-amyl-
JP-A-63-179953 and JP-A-Heisei 1-79 such as 2-hydroxyphenyl) ethyl) phenyl acrylate.
Acrylate compounds described in JP-B-168463; 2,6-di-t-butyl-4-methylphenol;
2,6-di-t-butyl-4-ethylphenol, octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, 2,2'-methylene-
Bis (4-methyl-6-t-butylphenol), 4,
4'-butylidene-bis (6-t-butyl-m-cresol), 4,4'-thiobis (3-methyl-6-t-butylphenol), bis (3-cyclohexyl-2-hydroxy-5-methylphenyl) ) Methane, 3,9-bis (2- (3- (3-t-butyl-4-hydroxy-5-
Methylphenyl) propionyloxy) -1,1-dimethylethyl) -2,4,8,10-tetraoxaspiro [5,5] undecane, 1,1,3-tris (2-methyl-4-hydroxy-5) -T-butylphenyl) butane, 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl)
Benzene, tetrakis (methylene-3- (3 ', 5'-
Di-tert-butyl-4'-hydroxyphenyl) propionate) methane [that is, pentaerythrityl-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate]], triethylene glycol bis (3- (3-tert-butyl-4-hydroxy-
Alkyl-substituted phenolic compounds such as 5-methylphenyl) propionate) and tocopherol; 6- (4-
Hydroxy-3,5-di-t-butylanilino) -2,
4-bis-octylthio-1,3,5-triazine, 6
-(4-hydroxy-3,5-dimethylanilino)-
2,4-bis-octylthio-1,3,5-triazine, 6- (4-hydroxy-3-methyl-5-tert-butylanilino) -2,4-bis-octylthio-1,3,3
5-triazine, 2-octylthio-4,6-bis-
(3,5-di-t-butyl-4-oxyanilino)-
Triazine group-containing phenolic compounds such as 1,3,5-triazine; and the like.

The phosphorus-based antioxidant is not particularly limited as long as it is commonly used in the general resin industry. For example, triphenyl phosphite, diphenyl isodecyl phosphite, phenyl diisodecyl phosphite, tris (Nonylphenyl) phosphite, tris (dinonylphenyl) phosphite, tris (2,4-
Di-t-butylphenyl) phosphite, tris (2-
t-butyl-4-methylphenyl) phosphite, tris (cyclohexylphenyl) phosphite, 2,2-
Methylenebis (4,6-di-t-butylphenyl) octyl phosphite, 9,10-dihydro-9-oxa-
10-phosphaphenanthrene-10-oxide, 1
0- (3,5-di-tert-butyl-4-hydroxybenzyl) -9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 10-decyloxy-9,10-dihydro-9 Monophosphite compounds such as -oxa-10-phosphaphenanthrene;
4'-butylidene-bis (3-methyl-6-t-butylphenyl-di-tridecyl phosphite), 4,4'-
Isopropylidene-bis (phenyl-di-alkyl (C
12-C15) phosphite), 4,4'-isopropylidene-bis (diphenylmonoalkyl (C12-C1
5) phosphite), 1,1,3-tris (2-methyl-4-di-tridecylphosphite-5-t-butylphenyl) butane, tetrakis (2,4-di-t-butylphenyl)- 4,4′-biphenylene phosphite,
Cyclic neopentanetetraylbis (octadecylphosphite), cyclic neopentanetetraylbis (isodecylphosphite), cyclic neopentanetetraylbis (nonylphenylphosphite), cyclic neopentanetetraylbis (2 ,
4-di-t-butylphenyl phosphite), cyclic neopentanetetraylbis (2,4-dimethylphenylphosphite), cyclic neopentanetetraylbis (2,6-di-t-butylphenylphosphite) ) And the like. Among these, monophosphite compounds are preferable, and tris (nonylphenyl) phosphite, tris (dinonylphenyl) phosphite, and tris (2,4-
Di-t-butylphenyl) phosphite and the like are particularly preferred.

Examples of the sulfur-based antioxidants include dilauryl 3,3'-thiodipropionate, dimyristyl 3,3'-thiodipropionate, distearyl 3,3'-thiodipropionate, lauryl stearyl 3 , 3'-thiodipropionate, pentaerythritol-tetrakis- (β-lauryl-thio-propionate), 3,9-bis (2-dodecylthioethyl)-
2,4,8,10-tetraoxaspiro [5,5] undecane and the like.

These antioxidants are each used alone.
Alternatively, two or more kinds can be used in combination.
The amount of the antioxidant is usually in the range of 0.001 to 5 parts by weight, preferably 0.01 to 1 part by weight, based on 100 parts by weight of the cyclic olefin resin.

For the purpose of improving weather resistance and the like, an ultraviolet inhibitor may be added. As the ultraviolet absorber, for example, 2,2,6,6-tetramethyl-4-piperidylbenzoate, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2,2
2,6,6-pentamethyl-4-piperidyl) -2-
(3,5-di-t-butyl-4-hydroxybenzyl)
-2-n-butylmalonate, 4- (3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyloxy) -1- (2- (3- (3,5-di-t Hindered amine-based ultraviolet absorbers such as -butyl-4-hydroxyphenyl) propionyloxy) ethyl) -2,2,6,6-tetramethylpiperidine; 2- (2-hydroxy-5-methylphenyl) benzotriazole,
(3-t-butyl-2-hydroxy-5-methylphenyl) -5-chlorobenzotriazole, 2- (3,5-
Benzotriazole ultraviolet absorbers such as di-t-butyl-2-hydroxyphenyl) -5-chlorobenzotriazole and 2- (3,5-di-t-amyl-2-hydroxyphenyl) benzotriazole; -Di-t-
Bezoate ultraviolet absorbers such as butylphenyl-3,5-di-t-butyl-4-hydroxybenzoate and hexadecyl-3,5-di-t-butyl-4-hydroxybenzoate; and the like. These ultraviolet absorbers can be used alone or in combination of two or more. The amount of the ultraviolet absorber is usually 0.001 to 5 with respect to 100 weight of the cyclic olefin resin.
Parts by weight, preferably in the range of 0.01 to 1 part by weight.

For the purpose of preventing dust and static electricity, an antistatic agent may be used. Examples of the antistatic agent include organic sulfonates such as sodium alkylsulfonate and phosphonium alkylsulfonate, fatty acid esters such as glycerin ester of stearic acid, and hydroxyamine compounds. These antistatic agents can be used alone or in combination of two or more. The compounding amount of the antistatic agent is usually in the range of 0.01 to 5 parts by weight based on 100 parts by weight of the cyclic olefin resin.

In addition, for example, pigments or dyes for coloring; antiblocking agents; lubricants such as natural oils, synthetic oils and waxes; and flame retardants may be blended. 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 to impair the object of the present invention.

(Molding Material) The molding material used in the present invention is a mixture of the above components in a cyclic olefin resin. The method of mixing is not particularly limited as long as the cyclic olefin resin and other polymer components and compounding agents are sufficiently dispersed. For example, there are a method of kneading the resin in a molten state with a mixer, a twin-screw kneader or the like, a method of dissolving and dispersing the resin in an appropriate solvent, and a method of removing the solvent by a coagulation method, a casting method, or a direct drying method.

In the case of kneading, it is appropriate that the resin temperature is set to a temperature of the glass transition temperature of the resin + 50 ° C. to the glass transition temperature + 150 ° C., and a sufficient uniform mixing state is obtained by sufficiently applying the shear. be able to.
If the resin temperature is too low, the viscosity becomes high and kneading is difficult. If it is too high, the resin and the rubbery polymer deteriorate, and the two cannot be kneaded well due to differences in viscosity and melting point. Kneading conditions, such as screw shape, should be appropriately set according to the type and shape of the kneader. It is preferable to perform preliminary kneading depending on the combination of the resin, the rubbery polymer to be used, and the apparatus used for kneading, and to determine the number of revolutions, residence time, and the like according to the combination. After kneading, it is usually extruded into a rod shape in a molten state, cut into an appropriate length by a strand cutter, and is often used as pellets.

(Molding Method) The animal breeding container of the present invention is obtained by molding the above molding material. The molding method may be in accordance with a conventionally known molding method, and includes injection molding, extrusion blow molding, injection blow molding, multilayer blow molding, connection blow molding, double wall blow molding, stretch blow molding, vacuum molding, rotational molding, and the like. No. The melting temperature of the resin at the time of molding varies depending on the type of the cyclic olefin resin, but is preferably 200 to 350 ° C. Further, as known in Japanese Patent Application Laid-Open No. 4-276253, multilayer molding with another resin or double-wall molding, further enhancing gas barrier properties, weather resistance, light resistance, etc., depending on the purpose,
This is possible as long as the visibility of the contents is not affected. Also,
Since the visibility of the contents of the animal breeding container is improved and the excrement of the animal can be easily washed away, the surface finish of the mold, especially the surface finish of the mold part corresponding to the container contents surface, usually has no shrinking processing etc. Emery cloth polishing finish,
It is preferable that the surface of the animal breeding container has a mirror-finished finish and that there is no visible large unevenness on the surface of the animal breeding container. However, irregularities may be provided mainly on a part of the outer surface for the purpose of decoration, identification of contents, and the like.

It is preferable that the main part including the bottom and side surfaces of the animal breeding container is integrally formed. However, although there are difficulties in terms of productivity and strength, it is necessary to form a part such as a plate-like molded product. The containers may be separately molded and fixed by bonding, welding, and combining irregularities, or a container having a desired shape may be formed by a combination of these methods.

Further, in order to improve the mechanical strength against a drop impact or the like, a reinforcing material such as a wire mesh is previously set in a metal mold at the time of molding, and is subjected to insert molding or other reinforcement after molding or during molding. The material may be used by being laminated on the surface of the animal breeding container.

When a molding material containing a rubbery polymer is used, the transparency of the animal breeding container generally decreases in many cases by adding a compounding agent such as a rubbery polymer. The degree of decrease in transparency differs depending on the resin, the compounding agent, and the compounding ratio. When a part of the surface of the animal breeding container is cut out and measured, the minimum value of the light transmittance in the wavelength region of 450 to 700 nm is determined. Usually, it is preferably at least 20%, preferably at least 30%, more preferably at least 40%. Even in the case of the same compounding agent and compounding agent amount, when the compounding agent forms and disperses microdomens, 0.3
When microdomains of not more than μm, particularly not more than 0.2 μm are formed, the compounding agent has a smaller diameter than the wavelength of visible light, and light is hardly scattered, so that it is excellent in transparency and is preferable. When a rubbery polymer and an etherified or esterified product of a polyhydric alcohol are used in combination, the diameter of the microdomain to be formed is dispersed to 0.15 μm or less, preferably 0.1 μm or less. This is preferred because it becomes easier.

(Container) The animal breeding container of the present invention is used for raising mammals such as rats and small rabbits, amphibians such as snakes, frogs, turtles and lizards as pets, and for small laboratory animals such as mice, rats and guinea pigs. Is suitable for breeding for drug development and safety testing. In particular, it is suitable as a container for small experimental animals because it has resistance to contamination from chemicals used in various animal experiments, is excellent in the ease of cleaning excrement, and withstands steam sterilization.

The shape of the animal breeding container is not particularly limited as long as it meets these purposes. However, it is preferred to have a flat bottom surface for breeding animals therein. In particular, in the case of a laboratory animal breeding container, the bottom, side surfaces and top surface are almost rectangular in terms of improving molding processability, improving the ease of excrement cleaning, and being able to compactly store an empty animal breeding container. It is preferable that the shape is a rectangular parallelepiped shape, and the upper surface or the side surface is open. A lid is usually attached to this open surface. A portion including such a bottom surface is hereinafter referred to as a main body.

The size of the main body of the animal breeding container may be appropriately selected depending on the kind of the animal or the number of animals to be bred. Suitably, one or more, preferably, for example, four or more small animals are bred therein, and it is preferred that the bred animals be bred without mental stress, It is preferable that the size be such that the state can be observed and the container can be easily handled when the container is put in and out of the storage place. The preferred size is 1 to 100 liters, more preferably 10 to 60 liters. If it is small, small animals are difficult to breed, or the number of animals that can be bred is small, and it may not be suitable for the purpose of breeding and comparing a plurality of specimens under the same conditions, which is the purpose of animal experiments. Also, if it is too large, there are difficulties such as difficulty in handling and storage space. Here, the internal volume means that if a large hole such as an animal removal port of the container is open, the inside of the container when it is closed, that is, the liquid such as water is stored mainly by the surface formed by the concave surface and the flat surface. It is defined as the maximum volume of liquid that can be stored when assumed. In addition, the length of each side of the bottom surface and the side surface is usually 50 to
800 mm, preferably 80 to 600 mm, and one side of the bottom surface is 80 to 1000 mm, preferably 100 to 80 mm.
0 mm, the ratio of the length of the bottom surface in the longitudinal direction to the length in the direction perpendicular thereto (length in the short direction / length in the longitudinal direction) is usually 0.4 to 1, preferably 0.5 to 1. When these conditions are satisfied, a space where animals can spend comfortably can be ensured, and storage of animal breeding containers is efficient and preferable.

[0053] The thickness of the animal breeding container is set at 0.
The range is 5 to 30.0 mm, preferably 0.7 to 25 mm, and more preferably 1.0 to 22 mm. If it is too thin, the mechanical strength is reduced and it is liable to break. If it is too thick, it is heavy and it is difficult to handle. However, there are no inconveniences in the number of holes for venting and taking in and out of animals as long as they do not impair the strength of the whole container and do not impair the purpose of use in the breeding container. Also, if the area is preferably 20% or less with respect to the sum of the areas of all surfaces such as the side surface and the bottom surface of the container except for the portion opened in one direction, the thickness is out of the preferable range of the thickness described above. Alternatively, there may be a thin portion, or a small hole other than the one-way hole may be opened. For example, a feed box or a water-only device may be attached to the top or side of the container, and such a portion may have the necessary holes. Further, for the purpose of improving the air permeability, one or a plurality of air holes may be provided on the upper surface or the side surface, preferably in such a size that the animals bred therein cannot escape.

The thickness of each of the bottom and sides is 0.5
４０40 mm, preferably 0.7 to 30 mm, more preferably 1.0 to 25 mm. It is preferable that the thickness t1 of the bottom portion is substantially equal to or greater than the thickness t2 of the side surface. However, as the thickness difference increases,
Since the stress concentration at the time of drop becomes large, preferably 0.7
≦ t1 / t2 ≦ 3, more preferably 0.8 ≦ t1 / t2
≦ 2.5, more preferably 0.9 ≦ t1 / t2 ≦ 2. In this case, the bottom thickness indicates the thickness of the thinnest portion at the bottom. By increasing the thickness, the amount of resin used in the container increases, which increases the cost or weight of the container. If it is too thin, problems such as a drop in drop strength occur. It is preferable in terms of impact strength that the thickness be uniform with the container animal breeding container side surface, but is not particularly limited.

Regarding the characteristics of the local shape of the animal breeding container, it is preferable that each of the constituent surfaces is a flat surface or a gentle curved surface, and the boundary between the surfaces preferably forms a gentle surface. Was found in the process of.

For example, when the container bottom surface and the container side surface form a continuous outer surface, the intersection, that is, the side, of both surfaces has a radius of curvature (hereinafter, this radius of curvature is referred to as RO), preferably 2.0 mm or more, and more preferably 2.0 mm or more. The present invention is preferably formed of a curved surface having a radius of curvature of not less than 3.0 mm so that the animal breeding container has good excrement resistance when used for a long period of time. Newly found by those. 2.0m radius of curvature on each side
If it is less than m, the stress when the animal breeding container is molded remains in this portion (hereinafter referred to as the residual stress of the animal breeding container or molded article), and the portion having a large residual stress is subjected to hot water treatment or steam sterilization treatment. The cracks (small cracks, appearing whitish in appearance) occur during the heat history such as heat generation, and excretions permeate here, making it difficult to clean. Due to the vicious circle of easy contamination, the problem that the contamination progresses more and more over a long period of use tends to occur, which is not preferable. In addition, when the radius of curvature is small, the strength against falling or the like is reduced, which is not preferable. Although there is no particular upper limit for the RO, if the value is unnecessarily large, the aspect portion is large in the animal breeding container, the flat portion on the bottom surface is relatively small, and the living space of the breeding animal is small, which is preferable. As a matter of fact, RO is usually 300 mm or less, preferably 200 mm
It is as follows.

Further, the animal breeding container of the present invention has a gentle curved surface with respect to each side (concave surface) of the inner surface of the container in addition to the curvature radius RO of each side (convex surface) of the outer surface of the container. (Hereinafter, the radius of curvature of the inner surface side is set to RI
), Having a good impact resistance, and a shape that facilitates cleaning of animal excrement. RI is usually 0.1-300m
m, preferably 0.5 to 200 mm. When the size is small, the excrement attached to the side is difficult to wash and has a structure that easily has residual stress. descend. If it is too large, the flat part of the bottom surface becomes relatively small similarly to the case where the RO is large, and the living space of the breeding animal becomes small, which is not preferable.

The values of RO and RI described above are values used as an index of the smoothness of the curved surface, assuming that the cross-sectional shape of the curved surface of the side is an arc, but the cross-sectional shape of the phase is not limited to an arc. There may be shapes with non-constant radii of curvature, such as parabolas and sinusoids. In this case, it is sufficient that the minimum value of the continuously changing radius of curvature in the phase is the value discussed above.

The portion where the thickness of the container is exposed, that is, the open surface or the edge of the hole is chamfered and rounded (hereinafter, radius of curvature r
). The size of the radius of curvature r of the edging is appropriately selected according to the purpose of use, but is usually 0.01
Those having a thickness of from 50 to 50 mm, preferably from 0.1 to 20 mm, are preferable because the residual stress can be sufficiently reduced and cracks due to contact with the chemical solution for a long period and cracks due to external impact can be reduced. Further, the end face may be gently folded (the radius of curvature on the convex side of this portion is represented as RE) to form a double-structured rim, which also improves the overall mechanical strength and improves the resistance to solvents and chemicals. It is preferable in that it can be carried in and out with a finger during handling. Further, a structure called a rib can be provided around the hole opened in one direction for the purpose of improving the impact strength and the like of the animal breeding container. The rib is a projection perpendicular to or close to the side surface, and the size is usually 1/20 to 19/2 of the height of the animal breeding container in the vertical direction (the height direction of the animal breeding container).
0, the lateral direction (direction perpendicular to the side surface of the animal breeding container) is usually 5 to 150 mm, and the thickness is usually 1/2 to 10 times the thickness of the side surface of the animal breeding container.

When the main body of the animal breeding container has a hole opened in one direction as described above, some lid is required. If possible, the lid for closing the hole may be integrally formed with the main body as a part of the animal breeding container of the present invention, or may be separately formed on the main body and the lid. As a part of the container of the present invention, those molded with a molding material composed of a cyclic olefin resin can be preferably used, but since there is less contamination such as excretion as compared with the main body, a transparent thermoplastic resin other than the cyclic olefin resin is used. It may be formed by molding a molding material such as a metal net or a metal plate. In the case where the container is separated into a lid and a main body, when the lid is molded with a cyclic olefin resin, the lid is not necessarily required to have strength, so it is not necessary to satisfy the above-mentioned preferred ranges of RO and RI on the side of the lid. However, it may be satisfied. Usually, the lid is provided with a ventilation hole, and water and a feed box can be attached thereto. In this case, it is not necessary to provide holes for water and bait on the side surface of the main body.

Further, in order to prevent excrement such as feces and urine and debris of food from adhering to the body of the animal and causing germs to adhere thereto, the bottom of the inside of the main body is provided with
It is also possible to provide a board or a wire mesh with holes in the shape of a saw blade in an arrangement almost parallel to the bottom surface. If possible, the plate with a hole in the shape of a mushroom can be molded integrally with the body using a molding material consisting of a cyclic olefin resin as a part of the body of the animal breeding container of the present invention, or a molding material consisting of a cyclic olefin resin Are preferably used, but if they are separable, they do not necessarily need to be transparent, and may be made of another material.

Further, since the surface of the animal breeding container is hard and slippery, it is not always comfortable for the breeding animal. Therefore, the animal is bred on a straw or a mat made of various fibers. You can do that.

[0063]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to only these examples. In particular, as for the shape of the animal breeding container, in the examples, a container having a simple structure is experimentally prepared and tested, but is not limited to this shape.

REFERENCE EXAMPLE 1 In 20 parts by weight of ethyltetracyclododecene (hereinafter abbreviated as ETCD), 200 parts by weight of cyclohexane, 2 parts by weight of 1-hexene, and toluene having a concentration of 15% by weight of triethylaluminum were added under nitrogen replacement. 15 parts by weight of the solution and 5 parts by weight of triethylamine were added, and 80 parts by weight of ETCD and 9 parts by weight of a toluene solution having a concentration of 20% by weight of titanium tetrachloride were continuously added over 60 minutes while stirring at 20 ° C. . Then 1
The reaction was allowed to proceed for 5 hours, and the reaction was stopped by adding 5 parts by weight of ethyl alcohol and 2 parts by weight of water.

After heating the reaction solution to 40 ° C. to hydrolyze the catalyst, 3 parts by weight of calcium sulfate and 60 parts by weight of cyclohexane were added to remove excess water. The precipitate containing the deposited metal was removed by filtration to obtain 371 parts by weight of a transparent polymer solution containing the ETCD ring-opening polymer.

The polymer solution 7 obtained by repeating this operation
50 parts by weight of Ni-diatomaceous earth catalyst (Nikki Chemical N1)
13) 15 parts by weight were added, and the mixture was placed in a pressure-resistant reaction vessel, hydrogen was introduced, and a hydrogenation reaction was performed at a pressure of 50 kg / cm ² and a temperature of 200 ° C. for 3 hours. After completion of the reaction, 700 parts by weight of cyclohexane was added for dilution, and the catalyst was removed by filtration to obtain 1350 parts by weight of a polymer solution containing a hydrogenated ring-opening polymer.

The retention time of 800 parts by weight of the cyclohexane solution of the hydrogenated ETCD ring-opening polymer obtained above in a column of 10 cm in inner diameter and 100 cm in length packed with 4.5 parts by weight of activated alumina (Neobeat D manufactured by Mizusawa Chemical) 100
Seconds and circulated for 24 hours. 550 parts by weight of this solution was poured into 1500 parts by weight of isopropanol with stirring to coagulate the hydrogenated ETCD ring-opening polymer. The coagulated ETCD ring-opened polymer hydrogenated product was recovered by filtration, and 2 parts with 300 parts by weight of isopropanol.
After washing twice, 5 torr, 12 in a rotary vacuum dryer.
After drying at 0 ° C. for 48 hours, 78 parts by weight of a hydrogenated ETCD ring-opening polymer was obtained.

The hydrogenated product of the ETCD ring-opening polymer was 8
The intrinsic viscosity [η] measured in decalin at 5 ° C is 0.4 d
1 / g, the ratio of Mw / Mn measured in terms of polystyrene by GPC using toluene as a solvent is 2.1, and the proton NM
The hydrogenation rate before and after the hydrogenation reaction was 99.8% or more by the R method, and the Tg measured by DSC was 140 ° C.
Met.

The obtained hydrogenated ETCD ring-opening polymer (refractive index 1.5242 at 25 ° C., ASTM D5
0.2 parts by weight of phenolic antioxidant pentaerythrityl-tetrakis (3- (3,5-di-tert-butyl-4-
(Hydroxyphenyl) propionate) and 0.4 part by weight of a hydrogenated styrene / butadiene / styrene / block copolymer (Tuftec H1051, manufactured by Asahi Kasei Kogyo Co., Ltd., crumb-shaped, refractive index 1.5173 at 30 ° C.) were mixed. Shaft kneader (Toshiba Machine, TEM35B type, different direction,
The resin was continuously kneaded at a resin temperature of 250 ° C. and a screw rotation speed of 100 rpm, and a strand (rod-shaped molten resin) was passed through a strand cutter to obtain a pellet (granular) molding material. This pellet is hot-pressed (resin temperature 200
20mm x 15m at 300 ° C, 300kgf / cm2, 3 minutes)
m, a plate having a thickness of 3.0 mm was formed. This board is transparent,
The light transmittance at 400 to 700 nm is at least 90.1%
Met. This plate was sliced to a thickness of about 0.05 μm, the polystyrene portion was stained with ruthenium tetroxide, and observed with a transmission electron microscope. As a result, the rubbery polymer was found to have a diameter of about 0.04 μm in a resin matrix. It had a spherical microdomain structure. The glass transition temperature of the pellet was 140 ° C.

First, the physical property test performed in this experiment will be described.

(Test Method 1: Transparency) Five BALB-c male mice (5 weeks old, CLEA Japan) were placed in an unused animal breeding container after molding, and the extent to which the animals were visually observed was observed. The mouse can be observed from around 1 m away, and the minimum value of the light transmittance at a wavelength of 450 to 700 nm measured by a spectrophotometer by cutting out a part of the container is 20% or more. It was judged to be good.

(Test Method 2: Heat Resistance) One of two unused animal breeding containers after molding was immersed in hot water for 30 minutes, and the change in shape was visually observed. Put another animal breeding container in an autoclave steam sterilizer.
The solution was sterilized at 20 ° C. for 20 minutes, taken out after decompression, and visually observed for change in shape. A case where no deformation was observed in both tests was judged to be particularly good.

(Test Method 3: Test for Easy Washing of Excrement) BALB-c male mice (5 weeks old,
After breeding 5 animals (Clea Japan, Inc.) for 14 days, fill the container with tap water almost completely, after 10 minutes, discard the water inside and wash off with more tap water for about 2 minutes, Excrement was physically removed by rubbing each side twice with a sponge. In particular, the bottom surface after drying was visually observed in detail, and it was confirmed that there was no stain or excrement left. If there was no stain or trace, it was judged to be good.

(Test Method 4: Long-Term Excretion Tolerance Test) BALB-c male mice (5 weeks old,
After breeding 5 mice for 7 days, remove the mouse and food from the container, fill the inside with almost completely tap water, and after 10 minutes, discard the inside water and run more tap water. For about 2 minutes. Each side was scrubbed 10 times with a sponge. If the excrement could not be physically removed by this scrubbing, the next stage was also recommended. The washed animal breeding container was placed in an autoclave steam sterilizer and sterilized at 121 ° C. for 20 minutes. This series 7
One day of breeding, running water washing and steam sterilization
Cycle. After performing this cycle for 10 cycles, the animal breeding container is visually inspected for the appearance of stains and excretions, and if no stains are found to be particularly good, the stains become increasingly remarkable. The mouse whose activity was confirmed by the mouse was judged to be good. In the middle of 10 cycles, a mouse in which the activity state became unobservable from the outside was judged to be bad.

(Test method 4-2: Long-term excretion resistance test 2) The animal breeding container tested in test method 4 is further subjected to a series of 7-day mouse rearing, running water washing and steam sterilization in test method 4 Perform the treatment for 40 cycles (50 cycles in total), visually observe the animal breeding container for stains and excretions, and make it particularly good if there is no stain, and 50 cycles if the stain gradually becomes remarkable. A mouse whose activity status could be confirmed from outside was determined to be good. Additional 4
A mouse in which the activity of the mouse became unobservable from the outside during the 0 cycle was judged to be bad.

(Test Method 5: Impact Resistance Test) 100 g of an iron nail as a weight is placed in an animal breeding container, and the container is tilted at 45 ° from the vertical direction and dropped on a concrete floor from a height of 120 cm. After dropping 10 pieces, it was observed whether there were any cracks or cracks, and it was judged that all the 10 pieces without cracks or cracks were good.

(Test Method 6: Test for Chemical Resistance) In this method, a test piece having a known flexural modulus is prepared, and the appearance of cracks (solvent cracks) in various test solvent solutions is measured in advance. By observing the solvent cracks that occur when the molded products are immersed in those solvents,
Tests residual stress and chemical resistance in animal breeding containers. The measurement of the residual stress (kg / cm ² ) was specifically performed by the Bergen method according to the following procedure.

Using the pellets obtained in Reference Example 1, JI
The flexural modulus E measured by the method shown in SK6911 was 22000 kgf / cm ² . Using the pellets of Reference Example 1, 20 m
A plate-shaped test piece having a size of mx 15 mm x a thickness of 3.0 mm was fixed in a longitudinal direction to a jig having an elliptical arc-shaped cross section, and methyl ethyl ketone and methyl acrylate were applied while external stress was continuously applied in the longitudinal direction. Immersed in three kinds of test liquids of ethyl alcohol for 2 hours, and measured the position where cracks (fine cracks became white) appeared in the longitudinal direction, and measured the stress at which the plate-shaped test piece could not withstand the three kinds of test liquids. Was measured.
As a result, the stress causing solvent crack with ethyl alcohol 210 kgf / cm ^2, the methyl acrylate, 120 kgf / cm ^2, was methylethylketone = 100kgf / cm ^2. Accordingly, the residual stress is determined as follows based on the occurrence of cracks after immersing the animal breeding container in the test solution for which the stress was measured for 2 hours.

The residual stress of an animal breeding container that does not cause solvent cracks in the methyl ethyl ketone test solution is 100%.
less than kgf / cm ^2, but causes a solvent crack in methyl ethyl ketone test solution, the residual stress of the animal rearing container that does not cause a solvent crack methyl acrylate test solution, 100 kgf / cm ² or more 120 kgf / cm ²
The residual stress of the animal breeding container that causes solvent cracks in the methyl alcohol relay test solution but does not cause solvent cracks in the ethyl alcohol test solution is 120 kg.
f / cm ² or more and less than 210 kgf / cm ² , the residual stress of the animal breeding container that causes solvent cracks in the ethyl alcohol test solution is 210 kgf / cm ² or more.

The chemical resistance of the animal breeding container
Judging that the solvent crack did not occur for the test liquids of the species was judged to be particularly good, and the solvent cracking occurred in the methyl ethyl ketone test liquid, but the solvent resistance did not cause the solvent crack in the methyl acrylate test liquid. Was determined.

(Example 1) The pellets of Reference Example 1 were injection-molded by a 350 ton injection molding machine at a mold temperature of 300 ° C and a mold temperature of 120 ° C.
A container having the following shape was prepared.

Shape: a rectangular bottom surface shown in FIG. 1 and four trapezoidal side surfaces in contact with it, having a volume close to a rectangular parallelepiped, no top surface (open), and an open surface rather than a bottom surface Pad-like shape with a slightly larger area.・ Thickness t1 of the bottom surface = 3.0 mm, thickness t2 of the side surface = 3.
0 mm.・ A radius of curvature RO = 10 on the outer side of the container between the bottom and the side.
mm, the radius of curvature RI inside the container is RI = 7.0 mm, the open side (upper side) has a radius of curvature RE = 10 mm, draws a gentle curve on the outside of the container, is folded down 15 mm downward, and the end face is downward. The edge of the end face is chamfered in a shape with a border, and the radius of curvature r = 0.2
mm ・ Area of bottom part (outside of container) 180 × 230mm ・ Area of top surface (opening) 188 × 238mm ・ Height 150mm ・ Volume 5.5 liter

The animal breeding container was very transparent in appearance, was not colored, the condition of the mouse could be easily confirmed, and the transparency was good. As a result of the heat resistance test, there is no deformation by hot water or steam sterilization,
Heat resistance was particularly good.

The results of the excrement easy cleaning test were good,
No excrement residue was observed. The results after the long-term excretion resistance test were particularly good, with no excrement left and no severe stains or discoloration observed.

When the residual stress was measured, it was 100 kg / cm
^{It was 2} or less, and solvent cracks did not occur with the three chemicals used, and the chemical resistance was particularly good. The result of the impact resistance test was good.

Reference Example 2 Hydrogenated styrene / butadiene /
A pellet-shaped molding material was obtained in the same manner as in Reference Example 1 except that the styrene-block copolymer was not used.

Example 2 An animal breeding container was obtained in the same manner as in Example 1 except that the molding material of Reference Example 2 was used instead of the molding material of Reference Example 1.

The animal breeding container had good transparency, particularly good heat resistance, and good results in the excrement easy cleaning test.

(Comparative Example 1) Polycarbonate resin (trade name Panlite L, manufactured by Teijin Chemicals Limited) was used as a molding material.
Except for using -1225), an animal breeding container was obtained in the same manner as in Example 1.

Although the animal breeding container had good transparency and particularly good heat resistance, as a result of the test for easy cleaning of excrement, a slight residue remained and was not good. The results after the long-term excretion resistance test showed that spots and coloring became remarkable as the cycles were repeated, and the activity status of the middle mice became difficult to understand at the 7th cycle. . Results of the long-term excretion resistance test were poor. In the chemical resistance test, solvent cracks occurred in any of the three chemicals used, and the chemical resistance was poor. The result of the impact resistance test was good.

(Embodiment 3) t1 = t2 = 3.0 mm, R
An animal breeding container was obtained in the same manner as in Example 1 except that 0 = 5.0 mm and RI = 2.0 mm.

The animal breeding container had good transparency, particularly good heat resistance, good results in the excrement easy cleaning test, and particularly good results after a long-term excretion resistance test. When the residual stress was measured, it was 100 kg / cm ² or less, and the chemical resistance was particularly good. The result of the impact resistance test was good.

(Embodiment 4) t1 = t2 = 2.0 mm, R
An animal breeding container was obtained in the same manner as in Example 1, except that 0 = 1.0 mm and RI <0.05 mm (particularly, the corresponding portion was not chamfered with a mold).

The animal breeding container had good transparency, particularly good heat resistance, good results in the excrement easy cleaning test, and particularly good results after a long-term excretion resistance test. The results after the long-term excretion resistance test were good, but slightly inferior to the particularly good level of Example 1 above. Although the state after 10 cycles was slightly excreted and stained, there was no particular problem in raising animals or observing the inside. When the residual stress is measured, it is 100 kg / cm
^{It was 2} or more and less than 120 kg / cm ² , and although the chemical resistance was good, it was slightly inferior to the particularly good one of Example 3. A drop test was performed using ten molded containers. Cracks were observed in two of them, and the mechanical strength was slightly inferior. However, when the drop height was reduced to 100 cm, no cracking occurred and the strength was slightly inferior, but it was judged that it was within the practical range.

(Reference Example 3) Hydrogenated styrene / butadiene /
A pellet-shaped molding material was obtained in the same manner as in Reference Example 1, except that the amount of the styrene / block copolymer was changed to 0.6 part by weight.

Reference Example 4 Hydrogenated styrene / butadiene /
A pellet-shaped molding material was obtained in the same manner as in Reference Example 1, except that the amount of the styrene / block copolymer was changed to 1.0 part by weight.

Reference Example 5 Hydrogenated styrene / butadiene /
A pellet-shaped molding material was obtained in the same manner as in Reference Example 1, except that the amount of the styrene / block copolymer was changed to 1.7 parts by weight.

Reference Example 6 Hydrogenated styrene / butadiene /
A pellet-shaped molding material was obtained in the same manner as in Reference Example 1, except that the amount of the styrene / block copolymer was 4.0 parts by weight.

Reference Example 7 Instead of 0.4 parts by weight of hydrogenated styrene / butadiene / styrene / block copolymer,
A glycerin ether compound (derived from nonylphenol) obtained by reacting 1.0 part by weight of the same hydrogenated styrene / butadiene / styrene / block copolymer with a condensate of nonylphenol and formaldehyde (average condensation number of nonylphenol component of 5.0) and glycidol In the same manner as in Reference Example 1, except that glycidol was bonded at an average ratio of 1.2 molecules per repeating unit and 0.2 parts by weight of an average molecular weight of 1,590), a pellet-like molding material was obtained. Was.

(Reference Example 8) Instead of 0.4 parts by weight of hydrogenated styrene / butadiene / styrene / block copolymer,
A pellet-shaped molding material was prepared in the same manner as in Reference Example 1 except that 0.4 parts by weight of the same hydrogenated styrene / butadiene / styrene / block copolymer and 0.5 parts by weight of the glycerin ether compound of Reference Example 7 were used. I got

Example 5 An animal breeding container was obtained in the same manner as in Example 1 except that the pellet obtained in Reference Example 3 was used as a molding material.

The animal breeding container has good transparency, particularly good heat resistance, good results in the excrement easy cleaning test, particularly good results after a long-term excretion resistance test, and residual stress of 1%.
The chemical resistance was particularly good at 00 kg / cm ² or less, and the result of the impact resistance test was good.

(Example 6) An animal breeding container was obtained in the same manner as in Example 1 except that the pellet obtained in Reference Example 4 was used as a molding material.

The animal breeding container has good transparency,
Compared with Example 5, the transparency was slightly lower in appearance, and the whole animal breeding container had a slightly whitish color. However, the expression of the mouse was clearly visible, and the activity state was observable from the outside, so that there was no practical problem. The heat resistance is particularly good, the result of the excrement easy cleaning test is good, the result after the long-term excrement resistance test is particularly good, and the residual stress is 100.
At less than kg / cm ² , the chemical resistance was particularly good, and the result of the impact resistance test was good.

Example 7 An animal breeding container was obtained in the same manner as in Example 1 except that the pellet obtained in Reference Example 5 was used as a molding material.

The animal breeding container has good transparency,
The whole animal breeding container had a whitish color as compared with Example 5 described above. However, the mouse in the middle was not able to know the fur and facial expression, but could understand the state of eating, and there was no hindrance in observing the activity state, and it seemed that there was no practical hindrance. The heat resistance is particularly good, the results of the excrement easy cleaning test are good, the results after the long-term excretion resistance test are particularly good, the residual stress is 100 kg / cm ² or less, the chemical resistance is particularly good, and the impact resistance is high. The results of the sex test were good.

(Example 8) An animal breeding container was obtained in the same manner as in Example 1 except that the pellet obtained in Reference Example 6 was used as a molding material.

Although the transparency of the animal breeding container was good, the transparency was slightly reduced, but it was judged that the container was practically usable. The heat resistance is particularly good, the results of the excrement easy cleaning test are good, and the results after the long-term excretion resistance test are particularly good.
The residual stress was 100 kg / cm ² or less, the chemical resistance was particularly good, and the result of the impact resistance test was good.

Example 9 An animal breeding container was obtained in the same manner as in Example 1 except that the molding material of Reference Example 7 was used instead of the molding material of Reference Example 1. The animal breeding container had particularly good transparency and heat resistance, and the result of the excrement easy cleaning test was good. In addition, a longer-term excretion resistance test 2
The results after performing (50 cycles) were good.

Example 10 An animal breeding container was obtained in the same manner as in Example 1 except that the molding material of Reference Example 8 was used instead of the molding material of Reference Example 1. The animal breeding container had particularly good transparency and heat resistance, and the result of the excrement easy cleaning test was good. In addition, the results after performing the long-term excretion resistance test 2 (50 cycles) were good.

[0111]

According to the present invention, an animal breeding container formed by molding a molding material comprising a cyclic olefin resin is provided. The container is characterized by being transparent, having excellent heat resistance, chemical resistance, and impact resistance as compared with the conventional animal breeding container, and furthermore, facilitating cleaning of animal excrement. The animal breeding container supplied by the present invention can be used to breed amphibians such as mammals such as rats and small rabbits, snakes, frogs, tortoises, lizards and the like as pets, and to transform small animals for experiments such as mice, rats and guinea pigs into pharmaceuticals The container can be bred for development and safety tests, and the container can be generally used for pets, and is extremely useful for experiments for the development of medicines and the like, and for industrial development.

[Brief description of the drawings]

FIG. 1 is a perspective view of an animal breeding container prepared in Example 1.

FIG. 2 is a longitudinal sectional view of the animal breeding container prepared in Example 1.

[Explanation of symbols]

 1: bottom surface 2: side surface 3: portion having a radius of curvature RO among sides 4: portion having a radius of curvature RI among sides 5: end surface 6: edge portion of double structure 7: rib

Claims (2)

[Claims] 1. An animal breeding container formed by molding a molding material comprising a cyclic olefin resin having a glass transition temperature of 100 ° C. or higher. 2. The animal breeding container according to claim 1, wherein a portion where the outer surface of the container bottom surface and the outer surface of the container side surface intersect is formed of a curved surface having a radius of curvature of 2.0 mm or more.