JP6160977B2 - Oxygen-absorbing resin composition - Google Patents

Description

  The present invention relates to an oxygen-absorbing resin composition. Specifically, the present invention relates to an oxygen-absorbing resin composition capable of maintaining quality without reducing the oxygen-absorbing ability of the oxygen-absorbing resin composition over a long period of time.

  Prevents oxygen oxidation of various products that are easily altered or deteriorated by the influence of oxygen, such as food, beverages, pharmaceuticals, and cosmetics, and removes oxygen in the package that contains them for the purpose of long-term storage. The oxygen absorber to be used is used.

  As the oxygen absorbent, an oxygen absorbent containing iron powder as a main reaction agent is generally used from the viewpoint of oxygen absorption capacity, ease of handling, and safety. However, since this iron-based oxygen absorbent is sensitive to a metal detector, it has been difficult to use the metal detector for foreign object inspection. Moreover, since the package which enclosed the iron-type oxygen absorber has a possibility of ignition, it cannot be heated with a microwave oven. Furthermore, since water is essential for the oxidation reaction of the iron powder, the effect of oxygen absorption could only be expressed when the material to be stored is of a high water content.

  In addition, the container is made of a multilayer material having an oxygen absorbing layer composed of an oxygen absorbing resin composition in which an iron-based oxygen absorbent is blended with a thermoplastic resin, thereby improving the gas barrier property of the container and improving the container itself. A packaging container having an oxygen absorbing function has been developed (see Patent Document 1). However, this container is also sensitive to metal detectors, so it cannot be used in that application, cannot be heated with a microwave oven, and has the effect that the effect is manifested only when the object to be stored is of a high moisture system. Have. Furthermore, since it is opaque, it has the subject that internal visibility is insufficient.

  On the other hand, an oxygen-absorbing resin composition comprising a resin and a transition metal catalyst is known. For example, a resin composition comprising a polyamide, particularly a xylylene group-containing polyamide as an oxidizing organic component, and a transition metal catalyst is known (see Patent Document 2). Furthermore, Patent Document 2 also exemplifies an oxygen absorbent, a packaging material, and a multilayer laminated film for packaging obtained by molding a resin composition.

  Further, as an oxygen-absorbing resin composition that does not require moisture for oxygen absorption, an oxygen-absorbing resin composition comprising a resin having a carbon-carbon unsaturated bond and a transition metal catalyst is known (see Patent Document 3). .

  Furthermore, as a composition for collecting oxygen, a composition comprising a polymer containing a substituted cyclohexene ring or a low molecular weight substance bonded to the cyclohexene ring and a transition metal is known (see Patent Document 4).

Japanese Patent Laid-Open No. 9-234832 JP 2001-252560 A Japanese Patent Laid-Open No. 05-115776 Special table 2003-521552 gazette

  However, the oxygen-absorbing resin composition described in the above-mentioned patent document continues to absorb oxygen when left in an atmosphere in which oxygen exists, for example, in air. Even if stored in a packaging container such as an aluminum bag, the oxygen absorption capacity gradually decreases due to the trace amount of oxygen remaining in the packaging container, and sufficient oxygen absorption capacity is obtained when processing and using various packaging materials. It has the problem of not expressing.

  The present invention has been made in view of the above problems, and its purpose is to improve the oxygen-absorbing ability of the resin composition during the period from production of the oxygen-absorbing resin composition to processing into various packaging materials. An object of the present invention is to provide an oxygen-absorbing resin composition that can be stored for a long period of time without lowering.

  As a result of intensive studies on a method capable of solving the above-mentioned problems, the present inventors have incorporated a specific amount of a transition metal catalyst into an oxygen-absorbing resin composition containing a polyester compound having a tetralin ring, thereby absorbing oxygen. The present inventors have found that the resin composition can be stored over a long period of time without reducing the ability, and completed the present invention.

That is, the present invention is as follows.
[1]
An oxygen-absorbing resin composition containing a polyester compound,
Structural units represented by the following general formulas (1) to (4):

(In the formula, each R is independently a halogen atom, alkyl group, alkenyl group, alkynyl group, aryl group, heterocyclic group, cyano group, hydroxy group, carboxyl group, ester group, amide group, nitro group, alkoxy group. Represents at least one monovalent substituent selected from the group consisting of a group, an aryloxy group, an acyl group, an amino group, a thiol group, an alkylthio group, an arylthio group, a heterocyclic thio group, and an imide group, In each formula, m independently represents an integer of 0 to 3, and in each formula, n independently represents an integer of 0 to 6, At least one hydrogen atom is bonded to the benzyl position of the tetralin ring, wherein each X is independently an aromatic hydrocarbon group, a saturated or unsaturated alicyclic hydrocarbon group, straight Selected from the group consisting of Jo or branched, saturated or unsaturated aliphatic hydrocarbon group and the heterocyclic group represents a divalent group containing at least one group.)
Comprising at least one tetralin ring selected from the group consisting of:
The oxygen-absorbing resin composition is an oxygen-absorbing resin composition containing a transition metal catalyst in an amount of 0.001 part by weight or more and 0.015 part by weight or less as a transition metal amount with respect to 100 parts by weight of the polyester compound.
[2]
The oxygen-absorbing resin composition according to the above [1], wherein the transition metal catalyst contains at least one transition metal selected from the group consisting of manganese, iron, cobalt, nickel and copper.
[3]
The oxygen-absorbing resin composition according to the above [1] or [2], wherein the shape of the oxygen-absorbing resin composition is at least one selected from the group consisting of pellets, powders, and flakes. .
[4]
The structural unit represented by the general formula (1) is represented by the following (5) to (7);

The oxygen-absorbing resin composition according to any one of [1] to [3], which is at least one selected from the group consisting of:

  According to the present invention, oxygen that can store the resin composition for a long period of time without reducing the oxygen absorption capacity during the period from the production of the oxygen-absorbing resin composition to the processing into various packaging materials. An absorbent resin composition can be provided.

  Hereinafter, embodiments of the present invention (hereinafter also referred to as “present embodiments”) will be described. In addition, the following embodiment is an illustration for demonstrating this invention, and this invention is not limited only to the embodiment.

[Oxygen-absorbing resin composition]
The oxygen-absorbing resin composition of the present embodiment is
An oxygen-absorbing resin composition containing a polyester compound,
Structural units represented by the following general formulas (1) to (4):

(In the formula, each R is independently a halogen atom, alkyl group, alkenyl group, alkynyl group, aryl group, heterocyclic group, cyano group, hydroxy group, carboxyl group, ester group, amide group, nitro group, alkoxy group. Represents at least one monovalent substituent selected from the group consisting of a group, an aryloxy group, an acyl group, an amino group, a thiol group, an alkylthio group, an arylthio group, a heterocyclic thio group, and an imide group, In each formula, m independently represents an integer of 0 to 3, and in each formula, n independently represents an integer of 0 to 6, At least one hydrogen atom is bonded to the benzyl position of the tetralin ring, wherein each X is independently an aromatic hydrocarbon group, a saturated or unsaturated alicyclic hydrocarbon group, straight Selected from the group consisting of Jo or branched, saturated or unsaturated aliphatic hydrocarbon group and the heterocyclic group represents a divalent group containing at least one group.)
Comprising at least one tetralin ring selected from the group consisting of:
The oxygen-absorbing resin composition is a resin composition containing a transition metal catalyst in an amount of 0.001 part by weight or more and 0.015 part by weight or less as a transition metal amount with respect to 100 parts by weight of the polyester compound.

[Tetralin ring-containing polyester compound]
The tetralin ring-containing polyester compound contained in the oxygen-absorbing resin composition of the present embodiment contains at least one of the structural units represented by the general formulas (1) to (4). The structural unit represented by the general formula (1) is preferably at least one selected from the group consisting of structural units represented by the above formulas (5) to (7). Here, “containing a structural unit” means that the compound has one or more of the structural unit. The structural unit is preferably contained as a repeating unit in the tetralin ring-containing polyester compound. The tetralin ring-containing polyester compound polymer may be any of a homopolymer of the structural unit, a random copolymer of the structural unit and another structural unit, and a block copolymer of the structural unit and another structural unit.

  In the structural units represented by the general formulas (1) to (4), examples of the monovalent substituent represented by R include a halogen atom (for example, a chlorine atom, a bromine atom, and an iodine atom), an alkyl group (preferably A linear, branched or cyclic alkyl group having 1 to 15 carbon atoms, more preferably 1 to 6 carbon atoms, such as a methyl group, ethyl group, n-propyl group, isopropyl group, t-butyl group, n -Octyl group, 2-ethylhexyl group, cyclopropyl group, cyclopentyl group), alkenyl group (preferably a linear, branched or cyclic alkenyl group having 2 to 10 carbon atoms, more preferably 2 to 6 carbon atoms, For example, vinyl group, allyl group), alkynyl group (preferably alkynyl group having 2 to 10 carbon atoms, more preferably 2 to 6 carbon atoms, such as ethynyl group, propargyl group), Group (preferably an aryl group having 6 to 16 carbon atoms, more preferably an aryl group having 6 to 10 carbon atoms, such as a phenyl group or a naphthyl group), a heterocyclic group (preferably having a carbon number of 1 to 12, more preferably A monovalent group obtained by removing one hydrogen atom from a 5-membered or 6-membered aromatic or non-aromatic heterocyclic compound having 2 to 6 carbon atoms, such as a 1-pyrazolyl group, 1 -Imidazolyl group, 2-furyl group), cyano group, hydroxy group, carboxyl group, ester group, amide group, nitro group, alkoxy group (preferably having 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms). A linear, branched or cyclic alkoxy group such as a methoxy group or an ethoxy group, an aryloxy group (preferably an aryloxy group having 6 to 12 carbon atoms, more preferably 6 to 8 carbon atoms, For example, a phenoxy group), an acyl group (including a formyl group, preferably an alkylcarbonyl group having 2 to 10 carbon atoms, more preferably 2 to 6 carbon atoms, preferably 7 to 12 carbon atoms, more preferably carbon atoms. An arylcarbonyl group having 7 to 9 carbon atoms, for example, an acetyl group, a pivaloyl group, a benzoyl group), an amino group (preferably having 1 to 10 carbon atoms, more preferably an alkylamino group having 1 to 6 carbon atoms, preferably An anilino group having 6 to 12 carbon atoms, more preferably 6 to 8 carbon atoms, preferably a heterocyclic amino group having 1 to 12 carbon atoms, more preferably 2 to 6 carbon atoms, such as an amino group, methyl Amino group, anilino group), thiol group, alkylthio group (preferably an alkylthio group having 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, such as methylthio group, ethyl Luthio group), an arylthio group (preferably an arylthio group having 6 to 12 carbon atoms, more preferably an arylthio group having 6 to 8 carbon atoms, such as a phenylthio group), a heterocyclic thio group (preferably having 2 to 10 carbon atoms, and more). Preferably a heterocyclic thio group having 1 to 6 carbon atoms, such as a 2-benzothiazolylthio group, an imide group (preferably an imide group having 2 to 10 carbon atoms, more preferably 4 to 8 carbon atoms, Examples thereof include N-succinimide group and N-phthalimide group), but are not particularly limited thereto.

  In addition, when said monovalent substituent R has a hydrogen atom, the hydrogen atom is a substituent T (Here, the substituent T is synonymous with what was demonstrated by said monovalent substituent R.). ) May be further substituted. Specific examples thereof include an alkyl group substituted with a hydroxy group (eg, hydroxyethyl group), an alkyl group substituted with an alkoxy group (eg, methoxyethyl group), and an alkyl group substituted with an aryl group (eg, benzyl). Group), an alkyl group substituted with a primary or secondary amino group (eg, aminoethyl group), an aryl group substituted with an alkyl group (eg, p-tolyl group), an aryl substituted with an alkyl group Examples thereof include, but are not particularly limited to, an oxy group (for example, 2-methylphenoxy group) and the like. When the monovalent substituent R has a monovalent substituent T, the carbon number described above does not include the carbon number of the substituent T. For example, a benzyl group is regarded as an alkyl group having 1 carbon atom substituted with a phenyl group, and is not regarded as an alkyl group having 7 carbon atoms substituted with a phenyl group. When the monovalent substituent R has a substituent T, the substituent T may have one or more kinds.

  In the structural units represented by the general formulas (1) to (4), X is an aromatic hydrocarbon group, a saturated or unsaturated alicyclic hydrocarbon group, a linear or branched saturated or unsaturated group. And a divalent group containing at least one group selected from the group consisting of an aliphatic hydrocarbon group and a heterocyclic group. Aromatic hydrocarbon group, saturated or unsaturated alicyclic hydrocarbon group, linear or branched saturated or unsaturated aliphatic hydrocarbon group and heterocyclic group may be substituted or unsubstituted . X may contain a hetero atom, or may contain an ether group, sulfide group, carbonyl group, hydroxy group, amino group, sulfoxide group, sulfone group or the like. Here, as the aromatic hydrocarbon group, for example, o-phenylene group, m-phenylene group, p-phenylene group, methylphenylene group, o-xylylene group, m-xylylene group, p-xylylene group, naphthylene group, Anthracenylene group, phenanthrylene group, biphenylene group, fluoronylene group and the like can be mentioned, but not limited thereto. Examples of the alicyclic hydrocarbon group include a cycloalkylene group such as a cyclopentylene group, a cyclohexylene group, a methylcyclohexylene group, a cycloheptylene group, and a cyclooctylene group, and a cycloalkenylene group such as a cyclohexenylene group. Although it is mentioned, it is not specifically limited to these. Examples of the aliphatic hydrocarbon group include methylene group, ethylene group, trimethylene group, propylene group, isopropylidene group, tetramethylene group, isobutylene group, tert-butylene group, pentamethylene group, hexamethylene group, heptamethylene group, Linear or branched alkylene groups such as octamethylene group, nonamethylene group, decamethylene group, vinylene group, propenylene group, 1-butenylene group, 2-butenylene group, 1,3-butadienylene group, 1-pentenylene group Alkenylene groups such as 2-pentenylene group, 1-hexenylene group, 2-hexenylene group, 3-hexenylene group and the like, but are not particularly limited thereto. Heterocyclic groups include five-membered rings containing one heteroatom such as furanyl, thiophenyl and pyrrolyl groups, six-membered rings containing one heteroatom such as pyridinyl, heteroatoms such as oxazolyl and thiazolyl. 5-membered ring containing two, 6-membered ring containing 2 heteroatoms such as pyridazinyl group, pyrimidinyl group, and other heteroatoms such as 5-, 6- and 7-membered rings containing at least one heteroatom, indolyl group, quinolinyl group, etc. A bicyclic fused heterocyclic group containing two heteroatoms such as a quinoxalinyl group, a tricyclic fused heterocyclic group containing one heteroatom such as an acridinyl group, and a heterocycle such as an indazolyl group. A bicyclic fused heterocyclic group containing two atoms, a polycyclic fused heterocyclic group containing at least one heteroatom, and the like are exemplified, but the invention is not particularly limited thereto. These may further have a substituent. Specific examples thereof include, for example, a halogen atom, an alkoxy group, a hydroxy group, a carboxyl group, a carboalkoxy group, an amino group, an acyl group, and a thio group (for example, an alkylthio group). Group, phenylthio group, tolylthio group, pyridylthio group, etc.), amino group (for example, unsubstituted amino group, methylamino group, dimethylamino group, phenylamino group, etc.), cyano group, nitro group, etc. It is not limited.

  The tetralin ring-containing polyester compound containing the structural unit represented by the general formula (1) is obtained by polycondensing a dicarboxylic acid having a tetralin ring or a derivative (I) thereof with a diol or a derivative (II) thereof. Can be obtained by:

  Examples of the dicarboxylic acid having a tetralin ring or its derivative (I) include compounds represented by the following general formula (8). The dicarboxylic acid having a tetralin ring or its derivative (I) can be used alone or in combination of two or more.

(In the formula, each R is independently a halogen atom, alkyl group, alkenyl group, alkynyl group, aryl group, heterocyclic group, cyano group, hydroxy group, carboxyl group, ester group, amide group, nitro group, alkoxy group. Represents at least one monovalent substituent selected from the group consisting of a group, an aryloxy group, an acyl group, an amino group, a thiol group, an alkylthio group, an arylthio group, a heterocyclic thio group, and an imide group, It may have a substituent, m represents an integer of 0 to 3, n represents an integer of 0 to 6, and at least one hydrogen atom is bonded to the benzyl position of the tetralin ring. Y represents each independently a hydrogen atom or an alkyl group.)

  The compound represented by the general formula (8) can be obtained, for example, by reacting a dicarboxylic acid having a naphthalene ring represented by the following general formula (9) or a derivative thereof with hydrogen.

(In the formula, each R is independently a halogen atom, alkyl group, alkenyl group, alkynyl group, aryl group, heterocyclic group, cyano group, hydroxy group, carboxyl group, ester group, amide group, nitro group, alkoxy group. Represents at least one monovalent substituent selected from the group consisting of a group, an aryloxy group, an acyl group, an amino group, a thiol group, an alkylthio group, an arylthio group, a heterocyclic thio group, and an imide group, (It may have a substituent. Each m independently represents an integer of 0 to 3. Y independently represents a hydrogen atom or an alkyl group.)

  Examples of the diol or its derivative (II) include ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, 1,3-propanediol, and 2-methyl-1,3-propane. Diol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol , Neopentyl glycol, 1,4-cyclohexanedimethanol, 2-phenylpropanediol, 2- (4-hydroxyphenyl) ethyl alcohol, α, α-dihydroxy-1,3-diisopropylbenzene, α, α-dihydroxy-1 4-diisopropylbenzene, o- xylene glycol, m- xylene glycol, p- xylene glycol, hydroquinone, 4,4-dihydroxyphenyl, naphthalene diol or derivatives thereof,. Diol or its derivative (II) can be used individually by 1 type or in combination of 2 or more types.

  Moreover, the tetralin ring-containing polyester compound containing the structural unit represented by the general formula (2) includes, for example, a diol having a tetralin ring or a derivative thereof (III), and a dicarboxylic acid or a derivative thereof (IV). It can be obtained by polycondensation.

  Examples of the diol having a tetralin ring or a derivative (III) thereof include compounds represented by the following general formula (10). A diol having a tetralin ring or a derivative (III) thereof can be used alone or in combination of two or more.

(In the formula, each R is independently a halogen atom, alkyl group, alkenyl group, alkynyl group, aryl group, heterocyclic group, cyano group, hydroxy group, carboxyl group, ester group, amide group, nitro group, alkoxy group. Represents at least one monovalent substituent selected from the group consisting of a group, an aryloxy group, an acyl group, an amino group, a thiol group, an alkylthio group, an arylthio group, a heterocyclic thio group, and an imide group, It may have a substituent, m represents an integer of 0 to 3, n represents an integer of 0 to 6, and at least one hydrogen atom is bonded to the benzyl position of the tetralin ring. )

  The compound represented by the general formula (10) can be obtained, for example, by reacting a diol having a naphthalene ring represented by the following general formula (11) or a derivative thereof with hydrogen.

(In the formula, each R is independently a halogen atom, alkyl group, alkenyl group, alkynyl group, aryl group, heterocyclic group, cyano group, hydroxy group, carboxyl group, ester group, amide group, nitro group, alkoxy group. Represents at least one monovalent substituent selected from the group consisting of a group, an aryloxy group, an acyl group, an amino group, a thiol group, an alkylthio group, an arylthio group, a heterocyclic thio group, and an imide group, (It may have a substituent. Each m independently represents an integer of 0 to 3.)

  Examples of the dicarboxylic acid or its derivative (IV) include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, 3, Benzenedicarboxylic acid such as 3-dimethylpentanedioic acid, phthalic acid, isophthalic acid, terephthalic acid, naphthalenedicarboxylic acid such as 2,6-naphthalenedicarboxylic acid, anthracene dicarboxylic acid, phenylmalonic acid, phenylenediacetic acid, phenylenedibutyric acid, Examples include 4,4-diphenyl ether dicarboxylic acid, p-phenylene dicarboxylic acid, or derivatives thereof. Dicarboxylic acid or its derivative (IV) can be used individually by 1 type or in combination of 2 or more types.

  The tetralin ring-containing polyester compound containing the structural unit represented by the above general formula (3) or (4) is obtained, for example, by polycondensing a hydroxycarboxylic acid having a tetralin ring or a derivative (V) thereof. Can do.

  Examples of the hydroxycarboxylic acid having a tetralin ring or a derivative (V) thereof include compounds represented by the following general formula (12) or (13). The hydroxycarboxylic acid having a tetralin ring or a derivative (V) thereof can be used alone or in combination of two or more.

(In the formula, each R is independently a halogen atom, alkyl group, alkenyl group, alkynyl group, aryl group, heterocyclic group, cyano group, hydroxy group, carboxyl group, ester group, amide group, nitro group, alkoxy group. Represents at least one monovalent substituent selected from the group consisting of a group, an aryloxy group, an acyl group, an amino group, a thiol group, an alkylthio group, an arylthio group, a heterocyclic thio group, and an imide group, It may have a substituent, m represents an integer of 0 to 3, n represents an integer of 0 to 6, and at least one hydrogen atom is bonded to the benzyl position of the tetralin ring. Y represents a hydrogen atom or an alkyl group.)

  The tetralin ring-containing polyester compound containing the structural unit represented by the general formula (1) or (2) is, for example, a polyester containing a structural unit represented by the following general formula (14) or (15) It can also be obtained by hydrogenation reaction of the compound.

(In the formula, each R is independently a halogen atom, alkyl group, alkenyl group, alkynyl group, aryl group, heterocyclic group, cyano group, hydroxy group, carboxyl group, ester group, amide group, nitro group, alkoxy group. Represents at least one monovalent substituent selected from the group consisting of a group, an aryloxy group, an acyl group, an amino group, a thiol group, an alkylthio group, an arylthio group, a heterocyclic thio group, and an imide group, Each independently represents an integer of 0 to 3. X is an aromatic hydrocarbon group, a saturated or unsaturated alicyclic hydrocarbon group, linear Or a divalent group containing at least one group selected from the group consisting of branched saturated or unsaturated aliphatic hydrocarbon groups and heterocyclic groups.)

(In the formula, each R is independently a halogen atom, alkyl group, alkenyl group, alkynyl group, aryl group, heterocyclic group, cyano group, hydroxy group, carboxyl group, ester group, amide group, nitro group, alkoxy group. Represents at least one monovalent substituent selected from the group consisting of a group, an aryloxy group, an acyl group, an amino group, a thiol group, an alkylthio group, an arylthio group, a heterocyclic thio group, and an imide group, Each independently represents an integer of 0 to 3. X is an aromatic hydrocarbon group, a saturated or unsaturated alicyclic hydrocarbon group, linear Or a divalent group containing at least one group selected from the group consisting of branched saturated or unsaturated aliphatic hydrocarbon groups and heterocyclic groups.)

  Specific examples of the monovalent substituent represented by R and the divalent group represented by X in the structural units represented by the general formulas (8) to (15) include the general formulas (1) to (4). It is the same as that described in the structural unit represented by Therefore, the duplicate description here is omitted.

  The tetralin ring-containing polyester compound contained in the oxygen-absorbing resin composition of the present embodiment includes structural units having other tetralin rings other than the structural units represented by the general formulas (1) to (4), and / or Or the structural unit which does not have a tetralin ring may be included as a copolymerization component. Specifically, the above-mentioned diol or its derivative (II) or the compound listed in the dicarboxylic acid or its derivative (IV) can be used as a copolymerization component.

  In addition, as other copolymerization components, at least one polyfunctional compound among trihydric or higher polyhydric alcohols, trivalent or higher polyhydric carboxylic acids and derivatives thereof, and trivalent or higher hydroxycarboxylic acids and derivatives thereof is used. Is mentioned. These polyfunctional compounds can be used alone or in combination of two or more.

  Specific examples of the trihydric or higher polyhydric alcohol include glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, 1,2,4-butanetriol, 1,2,5-pentanetriol, 1,2, Examples include 6-hexanetriol and sorbitol.

  Specific examples of trivalent or higher polyvalent carboxylic acids and derivatives thereof include propanetricarboxylic acid, trimellitic acid, trimellitic acid anhydride, pyromellitic acid, pyromellitic acid anhydride, benzophenonetetracarboxylic acid anhydride, Examples thereof include cyclopentatetracarboxylic acid anhydride and trimellitic acid trimethyl ester. Trivalent or higher polyvalent carboxylic acids or derivatives thereof can be used alone or in combination of two or more.

  Specific examples of the trivalent or higher-valent hydroxycarboxylic acid and derivatives thereof include malic acid, hydroxyglutaric acid, hydroxymethylglutaric acid, tartaric acid, citric acid, hydroxyisophthalic acid, and hydroxyterephthalic acid. Trivalent or higher valent hydroxycarboxylic acids can be used singly or in combination of two or more.

  Among the tetralin ring-containing polyester compounds containing the structural unit represented by the general formula (1), the tetralin ring-containing polyester containing the structural units represented by the above formulas (5) to (7) is more preferable. Examples thereof include polyester compounds and tetralin ring-containing polyester compounds containing structural units represented by the following formulas (16) to (18). When the tetralin ring-containing polyester compound contains structural units represented by the above formulas (5) to (7) and structural units represented by the following formulas (16) to (18), the raw material cost can be reduced. It tends to be.

The molecular weight of the tetralin ring-containing polyester compound in the present embodiment can be appropriately set in consideration of desired performance and handling properties, and is not particularly limited. In general, the weight average molecular weight (Mw) is preferably 1.0 × 10 ^{3 to} 8.0 × 10 ⁶ , more preferably 5.0 × 10 ^{3 to} 5.0 × 10 ⁶ . Similarly, the number average molecular weight (Mn) is preferably 1.0 × 10 ^{3 to} 1.0 × 10 ⁶ , and more preferably 5.0 × 10 ^{3 to} 5.0 × 10 ⁵ . In addition, all the molecular weights here mean the value of polystyrene conversion measured using gel permeation chromatography (GPC). In addition, said tetralin ring containing polyester compound can be used individually by 1 type or in combination of 2 or more types.

  Moreover, although the glass transition temperature (Tg) of the tetralin ring containing polyester compound in this embodiment is not specifically limited, It is preferable that it is 0-90 degreeC, More preferably, it is 10-80 degreeC. When the glass transition temperature is within the above preferable range, pelletization and drying at the time of manufacture are facilitated and oxygen absorption performance tends to be further improved as compared to the case where the glass transition temperature is not. The glass transition temperature here means a value measured by differential scanning calorimetry.

  The manufacturing method in particular of the tetralin ring containing polyester compound in this embodiment is not restrict | limited, All the manufacturing methods of conventionally well-known polyester can be applied. Examples of the method for producing polyester include a melt polymerization method such as a transesterification method and a direct esterification method, or a solution polymerization method. Among these, the transesterification method or the direct esterification method is preferable from the viewpoint of easy availability of raw materials.

  At the time of production of the tetralin ring-containing polyester compound, various catalysts such as transesterification catalysts, esterification catalysts, polycondensation catalysts, various stabilizers such as etherification inhibitors, heat stabilizers, light stabilizers, polymerization regulators and the like are conventionally known. Any of these can be used. These types and amounts used may be appropriately selected according to the reaction rate, the molecular weight of the tetralin ring-containing polyester compound, the glass transition temperature, the viscosity, the color tone, the safety, the thermal stability, the weather resistance, and the elution property of itself. There is no particular limitation. For example, the above-mentioned various catalysts include zinc, lead, cerium, cadmium, manganese, cobalt, lithium, sodium, potassium, calcium, nickel, magnesium, vanadium, aluminum, titanium, antimony, tin, and other metal compounds (for example, fatty acid salts Carbonate, phosphate, hydroxide, chloride, oxide, alkoxide) and metal magnesium. These can be used alone or in combination of two or more.

  The intrinsic viscosity of the tetralin ring-containing polyester compound (measured value at 25 ° C. using a mixed solvent of phenol and 1,1,2,2-tetrachloroethane in a mass ratio of 6: 4) is not particularly limited. From the viewpoint of moldability of the tetralin ring-containing polyester compound, it is preferably 0.1 to 2.0 dL / g, more preferably 0.5 to 1.5 dL / g.

  All of the above-mentioned tetralin ring-containing polyester compounds have hydrogen at the benzylic position of the tetralin ring, and when used in combination with the transition metal catalyst described above, the hydrogen at the benzylic position is extracted, thereby expressing oxygen absorption capacity. To do.

  Moreover, the oxygen-absorbing resin composition of the present embodiment is one in which odor generation after oxygen absorption is remarkably suppressed. Although the reason is not clear, for example, the following oxidation reaction mechanism is assumed. That is, in the above-mentioned tetralin ring-containing polyester compound, hydrogen at the benzyl position of the tetralin ring is first extracted to generate a radical, and then the carbon at the benzyl position is oxidized by the reaction between the radical and oxygen to produce a hydroxy group or It is thought that a ketone group is formed. Therefore, in the oxygen-absorbing resin composition of the present embodiment, the molecular chain of the oxygen-absorbing main agent is not broken by the oxidation reaction as in the prior art, the structure of the tetralin ring-containing polyester compound is maintained, and the cause of odor It is presumed that the low molecular weight organic compound is hardly generated after oxygen absorption, and as a result, the generation of odor after oxygen absorption is suppressed to the extent that it cannot be detected from the outside.

[Transition metal catalyst]
The transition metal catalyst contained in the oxygen-absorbing resin composition of the present embodiment is appropriately selected from known ones as long as it can function as a catalyst for the oxidation reaction of the tetralin ring-containing polyester compound. There is no particular limitation.

  Specific examples of the transition metal catalyst include transition metal organic acid salts, halides, phosphates, phosphites, hypophosphites, nitrates, sulfates, oxides, hydroxides, and the like. Here, examples of the transition metal contained in the transition metal catalyst include, but are not limited to, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, ruthenium, and rhodium. Among these, manganese, iron, cobalt, nickel, and copper are preferable and cobalt is more preferable from the viewpoint of the catalytic action for the oxygen absorption reaction. Examples of the organic acid of the organic acid salt include acetic acid, propionic acid, octanoic acid, lauric acid, stearic acid, acetylacetone, dimethyldithiocarbamic acid, palmitic acid, 2-ethylhexanoic acid, neodecanoic acid, linoleic acid, and toric acid. Oleic acid, capric acid, naphthenic acid, but are not limited thereto. The transition metal catalyst is preferably an organic acid salt obtained by combining the above-mentioned transition metal and an organic acid, and manganese, iron, cobalt, nickel or copper as the transition metal and acetic acid, stearic acid, 2-ethylhexanoic acid as the organic acid, An organic acid salt in which oleic acid or naphthenic acid is combined is more preferable. In addition, a transition metal catalyst can be used individually by 1 type or in combination of 2 or more types.

  Content of a transition metal catalyst is 0.015 mass part or less as a transition metal amount with respect to 100 mass parts of tetralin ring containing polyester compounds, Preferably it is 0.013 mass part or less. As a minimum of content of a transition metal catalyst, it is 0.001 mass part or more as a transition metal amount with respect to 100 mass parts of tetralin ring containing polyester compounds, Preferably it is 0.0025 mass part or more. The present inventors surprisingly combined the specific amount of the transition metal catalyst with the oxygen-absorbing resin composition containing the tetralin ring-containing polyester compound, and surprisingly, during storage before using the resin composition. It has been found that the oxygen absorption performance can be maintained for a long time without deteriorating.

  In addition, when the present inventors include the above-mentioned specific amount of transition metal catalyst, the oxygen absorption performance tends to be high under high humidity (for example, relative humidity of 80 to 100%). It was found that by keeping the temperature at a low humidity, it can be used without deterioration of oxygen absorption performance even after long-term storage. Therefore, in this embodiment, there exists an effect that the oxygen absorption performance of a resin composition is maintained over a longer period by storing a resin composition under low humidity (for example, 0-50% of relative humidity).

  The tetralin ring-containing polyester compound and the transition metal catalyst can be mixed by a known method. Moreover, the oxygen-absorbing resin composition having higher dispersibility can be obtained by kneading them using an extruder.

[Various additives]
Here, the oxygen-absorbing resin composition of the present embodiment contains various additives known in the art as optional components in addition to the components described above, as long as the effects of the present embodiment are not excessively impaired. May be. Examples of such optional components include desiccants, pigments such as titanium oxide, dyes, antioxidants, slip agents, antistatic agents, plasticizers, stabilizers and other additives, calcium carbonate, clay, mica, silica and the like. Although a filler, a deodorizing agent, etc. are mentioned, it is not specifically limited to these.

  Furthermore, the oxygen-absorbing resin composition of the present embodiment may further contain a radical generator and a photoinitiator as necessary in order to promote the oxygen absorption reaction. Specific examples of the radical generator include various N-hydroxyimide compounds. Specifically, for example, N-hydroxysuccinimide, N-hydroxymaleimide, N, N′-dihydroxycyclohexanetetracarboxylic acid diimide, N-hydroxyphthalimide, N-hydroxytetrachlorophthalimide, N-hydroxytetrabromophthalimide, N -Hydroxyhexahydrophthalimide, 3-sulfonyl-N-hydroxyphthalimide, 3-methoxycarbonyl-N-hydroxyphthalimide, 3-methyl-N-hydroxyphthalimide, 3-hydroxy-N-hydroxyphthalimide, 4-nitro-N-hydroxy Phthalimide, 4-chloro-N-hydroxyphthalimide, 4-methoxy-N-hydroxyphthalimide, 4-dimethylamino-N-hydroxyphthalimide, 4-carboxy-N-hydroxy Sahydrophthalimide, 4-methyl-N-hydroxyhexahydrophthalimide, N-hydroxyhetic acid imide, N-hydroxyhymic acid imide, N-hydroxytrimellitic acid imide, N, N-dihydroxypyromellitic acid diimide, etc. However, it is not particularly limited to these. Specific examples of the photoinitiator include, but are not limited to, benzophenone and its derivatives, thiazine dyes, metal porphyrin derivatives, anthraquinone derivatives, and the like. These radical generators and photoinitiators can be used singly or in combination of two or more.

[Other thermoplastic resins]
Further, the oxygen-absorbing resin composition of the present embodiment further contains other thermoplastic resin other than the tetralin ring-containing polyester compound as necessary, as long as the effects of the present embodiment are not excessively impaired. It may be. By using another thermoplastic resin in combination, it is possible to improve the formability and handleability when kneading with an extruder.
As other thermoplastic resins, known ones can be used as appropriate. Specifically, for example, low density polyethylene, medium density polyethylene, high density polyethylene, linear low density polyethylene, linear ultra low density polyethylene, polypropylene, poly-1-butene, poly-4-methyl-1-pentene, Alternatively, a polyolefin such as a random or block copolymer of α-olefins such as ethylene, propylene, 1-butene and 4-methyl-1-pentene; an acid-modified polyolefin such as maleic anhydride grafted polyethylene and maleic anhydride grafted polypropylene; Ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, ethylene-vinyl chloride copolymer, ethylene- (meth) acrylic acid copolymer and its ionic cross-linked product (ionomer), ethylene-methyl methacrylate copolymer Copolymer weight of ethylene-vinyl compound such as coalescence Body; polystyrene, styrene resin such as acrylonitrile-styrene copolymer, α-methylstyrene-styrene copolymer; polyvinyl compounds such as polymethyl acrylate and polymethyl methacrylate; nylon 6, nylon 66, nylon 610, nylon 12. Polyamide such as polymetaxylylene adipamide (MXD6); polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polytrimethylene terephthalate (PTT), polyethylene naphthalate (PEN), glycol-modified polyethylene terephthalate (PETG) Polyesters such as polyethylene succinate (PES), polybutylene succinate (PBS), polylactic acid, polyglycolic acid, polycaprolactone, polyhydroxyalkanoate; Boneto; While polyether such as polyethylene oxide or mixtures thereof, without limitation. These thermoplastic resins can be used individually by 1 type or in combination of 2 or more types.

[Usage]
For the oxygen-absorbing resin composition of the present embodiment, a known granulation method or a known molding method such as extrusion molding can be applied. For example, powder, granule, pellet, film or sheet Or other small pieces. Therefore, the oxygen-absorbing resin molded body obtained in this way can be used as an oxygen absorbent as it is, or by filling the obtained oxygen-absorbing resin molded body into a breathable packaging material, It can also be used as an oxygen absorbent package. Moreover, the oxygen-absorbing resin composition of the present embodiment formed into a film shape or a sheet shape can also be used in the form of a label, a card, a packing or the like. Here, a film having a thickness of 0.1 to 500 μm is classified as a film and a sheet having a thickness exceeding 500 μm.

  Here, the pellet-shaped oxygen-absorbing resin molded body is preferably further pulverized into a powder form from the viewpoint of increasing the contact area with oxygen and expressing the oxygen absorption performance more effectively. .

  In addition, as said breathable packaging material, the well-known packaging material which has air permeability can be applied, and it is not specifically limited. From the viewpoint of sufficiently exhibiting the oxygen absorbing effect, the breathable packaging material is preferably highly breathable. Specific examples of breathable packaging materials include highly breathable packaging materials used in various applications, such as paper such as Japanese paper, paper, and rayon paper; various fibers obtained from pulp, cellulose, and synthetic resin. Nonwoven fabric used; plastic film or perforated material thereof; or microporous film stretched after adding calcium carbonate or the like; and a laminate of two or more selected from these; Not. In addition, as a plastic film, for example, a film of polyethylene terephthalate, polyamide, polypropylene, polycarbonate or the like, and as a seal layer, a film of polyethylene, ionomer, polybutadiene, ethylene acrylic acid copolymer, ethylene methacrylic acid copolymer or ethylene vinyl acetate copolymer, etc. A laminated film and the like which are laminated and bonded can also be used.

  In the case where the oxygen-absorbing resin composition of the present embodiment is used after being formed into a film or sheet, it is preferable to provide fine voids in the film or sheet by stretching after the forming. If it does in this way, the oxygen permeability of a film or a sheet | seat will further improve, and there exists a tendency for the oxygen absorption capability of a tetralin ring containing polyester compound to express especially effectively.

  Furthermore, the oxygen-absorbing resin composition of the present embodiment molded into a film or sheet can be used as a packaging material or a packaging container in a single layer form, and this is laminated with another substrate. It can also be used in the form of a combined laminate. As a typical example of such a laminate, at least one layer composed of the oxygen-absorbing resin composition of the present embodiment and at least one layer selected from other resin layers, paper base material layers, metal foil layers, and the like are overlapped. The laminate can be used as an oxygen-absorbing multilayer packaging material and an oxygen-absorbing multilayer packaging container. In general, the oxygen-absorbing resin composition (layer) of the present embodiment formed into a film or sheet is provided on the inner side of the outer surface of the container or the like so as not to be exposed on the outer surface of the container or the like. Is preferred. Also, from the viewpoint of avoiding direct contact with the contents, the oxygen-absorbing resin composition (layer) of the present embodiment formed into a film or sheet is provided outside the inner surface of a container or the like. Is preferred. Thus, when using in a multilayer laminated body, it is preferable to arrange | position the oxygen-absorbing-resin composition (layer) of this embodiment shape | molded in the film form or the sheet form as at least 1 intermediate | middle layer. .

  As a preferable aspect of the above laminate, at least three of a sealant layer containing a thermoplastic resin, an oxygen absorbing layer containing the oxygen absorbing resin composition of the present embodiment, and a gas barrier layer containing a gas barrier substance are used. An oxygen-absorbing multilayer body having layers in this order may be mentioned. Here, having at least three layers in this order means that the sealant layer, the oxygen absorption layer, and the gas barrier layer are arranged in this order, and the sealant layer, the oxygen absorption layer, and the gas barrier layer are directly overlaid. Not only the mode (hereinafter referred to as “sealant layer / oxygen absorption layer / gas barrier layer”), but also a resin layer between the sealant layer and the oxygen absorption layer, or between the oxygen absorption layer and the gas barrier layer. , At least one or more other layers (hereinafter also referred to as “intermediate layer”) such as a metal foil layer or an adhesive layer (for example, “sealant layer / resin layer / oxygen absorbing layer / adhesive layer / Gas barrier layer ”,“ sealant layer / resin layer / adhesive layer / oxygen absorption layer / adhesive layer / resin layer / adhesive layer / gas barrier layer / adhesive layer / support ”, etc. Even in The way is.).

  In addition, as another preferable aspect of the laminate, a sealant layer containing a polyolefin resin, an oxygen absorbing layer containing the oxygen absorbing resin composition of the present embodiment, and a gas barrier layer containing a gas barrier substance And an oxygen-absorbing multilayer body having at least three layers in this order.

  The thermoplastic resin and polyolefin resin used in the sealant layer are appropriately selected in consideration of compatibility with other adjacent layers (oxygen absorption layer, gas barrier layer, resin layer, adhesive layer, support, etc.). It is preferable to do.

  As the gas barrier material used for the gas barrier layer, a gas barrier thermoplastic resin, a gas barrier thermosetting resin, various deposited films such as silica, alumina, and aluminum, and a metal foil such as an aluminum foil can be used. Examples of the gas barrier thermoplastic resin include ethylene-vinyl alcohol copolymer, MXD6, and polyvinylidene chloride. Examples of the gas barrier thermosetting resin include a gas barrier epoxy resin, for example, trade name “MAXIVE” manufactured by Mitsubishi Gas Chemical Co., Ltd.

  As a method for producing the oxygen-absorbing multilayer body, known methods such as a co-extrusion method, various laminating methods, and various coating methods can be applied depending on the properties of various materials, processing purposes, processing steps, and the like. There is no particular limitation. For example, a film or sheet is produced by extruding a resin composition melted through a T die, a circular die, or the like from an attached extruder, or an oxygen absorbing film or sheet is coated with an adhesive and another film or sheet is produced. It can shape | mold by the method of bonding together. In addition, a multilayer container having a predetermined shape or a preform for manufacturing a container can be formed by co-injecting or sequentially injecting a molten resin into an injection mold through a multilayer multiple die using an injection machine. The preform is heated to a stretching temperature, stretched in the axial direction, and blow stretched in the circumferential direction by fluid pressure to obtain a stretch blow bottle.

  Furthermore, for example, a film-like oxygen-absorbing multilayer body can be processed into a bag shape or a lid material. Further, for example, a sheet-like oxygen-absorbing multilayer body is thermoformed into an oxygen-absorbing multilayer container having a predetermined shape such as a tray, a cup, a bottle, or a tube by a molding method such as vacuum forming, pressure forming, or plug assist molding. Can do. And the bag-shaped container and cup-shaped container obtained in this way can perform a boil process of 80-100 degreeC, a semi-retort, a retort, or a high retort process of 100-135 degreeC. In addition, the bag-like container is a pouch with an easy-to-open mouth that is compatible with microwave cooking, by filling the contents such as food, and then providing an opening to release steam from the opening during microwave cooking. It can be preferably used.

  In using the oxygen-absorbing resin composition of the present embodiment, it is possible to irradiate energy rays to promote the start of the oxygen absorption reaction or increase the oxygen absorption rate. As the energy ray, for example, visible light, ultraviolet ray, X-ray, electron beam, γ-ray or the like can be used. The amount of irradiation energy can be appropriately selected according to the type of energy beam used.

The oxygen-absorbing resin composition of the present embodiment is particularly excellent in oxygen-absorbing performance under high-humidity conditions (relative humidity 80% to 100%), and in particular, there is no odor generation after oxygen absorption. It can be particularly suitably used in cooked foods, beverages, health foods, pharmaceuticals and the like. That is, the oxygen-absorbing resin composition of the present embodiment and various molded articles such as laminates using the same are particularly excellent in oxygen-absorbing performance under high-humidity conditions (relative humidity of 80% to 100%) and the content. Since it has excellent flavor retention, it is suitable for packaging articles with high water activity. In addition, the oxygen-absorbing resin composition of the present embodiment is different from the oxygen-absorbing resin composition using conventional iron powder, and is not stored due to the presence of iron (for example, alcoholic beverages or carbonated beverages). Can be suitably used. The “water activity” is a scale indicating the free water content in an article, and is indicated by a number from 0 to 1, with 0 for an article without moisture and 1 for pure water. That is, the water activity Aw of a certain article is expressed as follows: the water vapor pressure in the space after the article is sealed and reached an equilibrium state is P, the water vapor pressure of pure water is P ₀ , and the relative humidity in the space is RH (%). , And
Aw = P / P ₀ = RH / 100
Is defined.

  Specific examples of stored items include beverages such as milk, juice, coffee, teas, alcoholic beverages; liquid seasonings such as sauces, soy sauce, noodle soups, dressings; cooked foods such as soups, stews, and curries; jams, mayonnaise Pasty foods such as tuna, fish and shellfish; processed milk products such as cheese, butter and eggs; processed meat products such as meat, salami, sausage and ham; carrots, potatoes, asparagus, shiitake mushrooms Vegetables such as; Fruits; Eggs; Noodles; Processed rice or processed food such as cooked rice, red rice, rice cake, rice bran; Confectionery such as mutton, pudding, cake, buns; Adhesives, adhesives, pesticides, Chemicals such as insecticides; pharmaceuticals; health foods such as vitamins; pet foods; miscellaneous goods such as cosmetics, shampoos, rinses, and detergents; It is not particularly limited in La. In particular, preserved items that are prone to deterioration in the presence of oxygen, such as beer, wine, fruit juice beverages, fruit juices, vegetable juices, soft carbonated drinks, teas, etc. for beverages, fruits, vegetables, meat products, infant foods for foods, etc. , Coffee, jam, mayonnaise, ketchup, edible oil, dressing, sauces, boiled dairy products, dairy products, etc., and other suitable packaging materials for pharmaceuticals and cosmetics.

  In addition, before and after filling (packaging) of these objects to be preserved, the container or the object to be preserved can be sterilized in a form suitable for the object to be preserved. As the sterilization method, for example, heat sterilization at 100 ° C. or lower, pressurized hot water treatment at 100 ° C. or higher, heat sterilization such as ultrahigh temperature heat treatment at 130 ° C. or higher, sterilization by electromagnetic waves such as ultraviolet rays, microwaves, gamma rays Examples thereof include gas treatment such as ethylene oxide, and chemical sterilization such as hydrogen peroxide and hypochlorous acid.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto. Unless otherwise specified, NMR measurements were performed at room temperature. Moreover, in the present Example and the comparative example, the measurement of various physical-property values was implemented with the following measuring methods and measuring apparatuses.

(Measurement method of glass transition temperature)
The glass transition temperature was measured according to JIS K7122. The measuring apparatus used was “DSC-60” manufactured by Shimadzu Corporation.

(Measuring method of melting point)
The melting point was determined by measuring the DSC melting point peak temperature according to ISO11357. The measuring apparatus used was “DSC-60” manufactured by Shimadzu Corporation.

(Measurement method of weight average molecular weight and number average molecular weight)
The weight average molecular weight and the number average molecular weight were measured by GPC-LALLS. As a measuring apparatus, “Shodex GPC-2001” manufactured by Showa Denko KK was used.

[Monomer synthesis example]
An autoclave having an internal volume of 18 L was charged with 2.20 kg of dimethyl naphthalene-2,6-dicarboxylate, 11.0 kg of 2-propanol, and 350 g (50 wt% water-containing product) of 5% palladium supported on activated carbon. Next, after the air in the autoclave was replaced with nitrogen, and further nitrogen was replaced with hydrogen, hydrogen was supplied until the pressure in the autoclave reached 0.8 MPa. Next, the agitator was started, the rotation speed was adjusted to 500 rpm, the internal temperature was raised to 100 ° C. over 30 minutes, and hydrogen was further supplied to make the pressure 1 MPa. Thereafter, the supply of hydrogen was continued so as to maintain 1 MPa according to the pressure drop due to the progress of the reaction. Since the pressure drop disappeared after 7 hours, the autoclave was cooled, unreacted residual hydrogen was released, and then the reaction solution was taken out from the autoclave. The reaction solution was filtered to remove the catalyst, and then 2-propanol was evaporated from the separated filtrate with an evaporator. To the obtained crude product, 4.40 kg of 2-propanol was added and purified by recrystallization to obtain dimethyl tetralin-2,6-dicarboxylate in a yield of 80%. The NMR analysis results of the obtained dimethyl tetralin-2,6-dicarboxylate are as follows.
¹ H-NMR (400 MHz CDCl ₃ ) δ 7.76-7.96 (2H m), 7.15 (1H d), 3.89 (3H s), 3.70 (3H s), 2.70-3.09 (5H m), 2.20-2.25 (1H m), 1.80-1.95 (1H m)

[Polymer production example]
(Production Example 1)
Tetralin-2,6-dicarboxylic acid obtained in the monomer synthesis example in a polyester resin production apparatus equipped with a fractionator, a total condenser, a cold trap, a stirrer, a heating device, and a nitrogen introduction pipe, etc. Dimethyl 543 g, 1,4-butanediol 315 g, and tetrabutyl titanate 0.171 g were charged, and the temperature was raised to 230 ° C. in a nitrogen atmosphere to perform a transesterification reaction. After the reaction conversion rate of the dicarboxylic acid component reached 85% or more, 0.171 g of tetrabutyl titanate was further added, the temperature was increased and the pressure was gradually reduced, polycondensation was performed at 245 ° C. and 133 Pa or less, and polyester compound A Got.

As a result of measuring the weight average molecular weight and number average molecular weight of the obtained polyester compound A by GPC (gel permeation chromatography), the weight average molecular weight in terms of polystyrene was 8.7 × 10 ⁴ , and the number average molecular weight was 3.1 ×. 10 was ^4. Moreover, as a result of measuring the glass transition temperature and melting | fusing point of the polyester compound A by DSC, the glass transition temperature was 36 degreeC and melting | fusing point was 145 degreeC.

(Production Example 2)
Polyester compound B was synthesized in the same manner as in Production Example 1 except that 1,4-butanediol in Production Example 1 was changed to ethylene glycol and its weight was changed to 217 g. This polyester compound B was not recognized because the polystyrene-equivalent weight average molecular weight was 8.5 × 10 ⁴ , the number average molecular weight was 3.0 × 10 ⁴ , the glass transition temperature was 67 ° C., and the melting point was amorphous.

(Production Example 3)
Polyester compound C was synthesized in the same manner as in Production Example 1 except that 1,4-butanediol in Production Example 1 was changed to 1,6-hexanediol and its weight was changed to 413 g. This polyester compound C had a weight average molecular weight of 8.9 × 10 ⁴ , a number average molecular weight of 3.3 × 10 ⁴ , a glass transition temperature of 16 ° C., and a melting point of 137 ° C.

Example 1
An oxygen-absorbing resin composition obtained by dry blending cobalt stearate (II) with a cobalt content of 0.012 parts by mass with respect to 100 parts by mass of polyester compound A 2 having two screws having a diameter of 37 mm Oxygen-absorbing resin composition pellets are supplied to a shaft extruder at a rate of 15 kg / h, melt kneaded under conditions of a cylinder temperature of 220 ° C., extruded strands from the extruder head, cooled, and pelletized. Got.

  Using a twin screw extruder having two 20 mm diameter screws, 1000 g of the obtained oxygen-absorbing resin composition pellets were extruded at 220 ° C., screw rotation speed 60 rpm, feed screw rotation speed 12 rpm, take-off speed 1.3 m. By forming the film under the conditions of / min, an oxygen-absorbing film having a width of 130 mm and a thickness of 95 to 105 μm was produced.

  The obtained oxygen-absorbing film was put into a four-side sealed bag laminated with aluminum foil, filled so that the amount of air in the bag was 500 mL, adjusted to a relative humidity of 100%, and then sealed by heat sealing, It preserve | saved for one month in a 30 degreeC thermostat. Then, the gas in the bag is sampled using a syringe, the oxygen concentration in the bag is measured using a zirconia oxygen analyzer (“LC-750F” manufactured by Toray Engineering Co., Ltd.), and the oxygen absorption capacity per gram of film Was calculated.

  On the other hand, 1000 g of the obtained oxygen-absorbing resin composition pellets were put into a four-sided seal bag in which aluminum foils of 40 cm in length and 30 cm in width were laminated, the headspace was set to approximately 0 mL, and then sealed by heat sealing. The initial oxygen amount in the container at this time was about 850 mL. After storing this at room temperature for 6 months, the bag was opened, the pellet was taken out, an oxygen-absorbing film was produced under the same conditions as above, and the oxygen-absorbing ability was calculated.

Subsequently, the oxygen absorption performance retention rate after 6 months storage with respect to before 6 months storage was calculated and evaluated. The oxygen absorption performance retention rate was calculated by the following formula.
Retention rate (%) = (Oxygen absorption after 6 months storage / Oxygen absorption before 6 months storage) × 100

(Example 2)
A film was prepared by the same method as in Example 1 except that cobalt stearate (II) was dry blended so that the amount of cobalt was 0.01 parts by mass, and a storage test was carried out to maintain and absorb oxygen. Rate was evaluated. The evaluation results are shown in Table 1.

(Example 3)
A film was prepared by the same method as in Example 1 except that cobalt stearate (II) was dry blended so that the amount of cobalt was 0.005 parts by mass, and a storage test was conducted to obtain oxygen absorption capacity and retention. Rate was evaluated. The evaluation results are shown in Table 1.

Example 4
A film was prepared in the same manner as in Example 1 except that polyester compound B was used in place of polyester compound A, and a storage test was conducted to evaluate oxygen absorption capacity and retention. The evaluation results are shown in Table 1.

(Example 5)
A film was prepared by the same method as in Example 4 except that cobalt stearate (II) was dry blended so that the amount of cobalt was 0.01 parts by mass, and a storage test was conducted to store and absorb oxygen. Rate was evaluated. The evaluation results are shown in Table 1.

(Example 6)
A film was prepared by the same method as in Example 4 except that cobalt stearate (II) was dry blended so that the amount of cobalt was 0.005 parts by mass, and a storage test was conducted to maintain and absorb oxygen. Rate was evaluated. The evaluation results are shown in Table 1.

(Example 7)
A film was prepared by the same method as in Example 1 except that the polyester compound C was used in place of the polyester compound A, and a storage test was conducted to evaluate the oxygen absorption capacity and the retention rate. The evaluation results are shown in Table 1.

(Example 8)
A film was prepared by the same method as in Example 7 except that cobalt (II) stearate was dry blended so that the amount of cobalt was 0.01 parts by mass, and a storage test was carried out to maintain and absorb oxygen. Rate was evaluated. The evaluation results are shown in Table 1.

Example 9
A film was prepared by the same method as in Example 7 except that cobalt stearate (II) was dry blended so that the amount of cobalt was 0.005 parts by mass, and a storage test was carried out to maintain and absorb oxygen. Rate was evaluated. The evaluation results are shown in Table 1.

(Comparative Example 1)
A film was prepared by the same method as in Example 1 except that cobalt stearate (II) was dry blended so that the amount of cobalt was 0.05 parts by mass, and a storage test was carried out. Rate was evaluated. The evaluation results are shown in Table 1.

(Comparative Example 2)
A film was prepared by the same method as in Example 4 except that cobalt stearate (II) was dry blended so that the amount of cobalt was 0.05 parts by mass, and a storage test was conducted to determine the oxygen absorption capacity and retention. Rate was evaluated. The evaluation results are shown in Table 1.

(Comparative Example 3)
A film was prepared in the same manner as in Example 7 except that cobalt stearate (II) was dry blended so that the amount of cobalt was 0.05 parts by mass, and a storage test was carried out to maintain and absorb oxygen. Rate was evaluated. The evaluation results are shown in Table 1.

  As is clear from the results shown in Table 1, the oxygen-absorbing resin composition (Examples 1 to 1) in which the cobalt content is 0.001 part by weight or more and 0.015 part by weight or less with respect to 100 parts by weight of the polyester compound. In No. 9), the retention rate of oxygen absorption performance was 90% or more even after 6 months of storage, and the resin composition could be stored for a long period of time without reducing the oxygen absorption capacity.

  On the other hand, the oxygen-absorbing resin composition (Comparative Examples 1 to 3) in which the cobalt content exceeds 0.015 parts by mass with respect to 100 parts by mass of the polyester compound has a remarkable oxygen-absorbing ability after 6 months storage. Declined.

Claims (4)

An oxygen-absorbing resin composition containing a polyester compound,
Structural units represented by the following general formulas (1) to (4):
(In the formula, each R is independently a halogen atom, alkyl group, alkenyl group, alkynyl group, aryl group, heterocyclic group, cyano group, hydroxy group, carboxyl group, ester group, amide group, nitro group, alkoxy group. Represents at least one monovalent substituent selected from the group consisting of a group, an aryloxy group, an acyl group, an amino group, a thiol group, an alkylthio group, an arylthio group, a heterocyclic thio group, and an imide group, In each formula, m independently represents an integer of 0 to 3, and in each formula, n independently represents an integer of 0 to 6, At least one hydrogen atom is bonded to the benzyl position of the tetralin ring, wherein each X is independently an aromatic hydrocarbon group, a saturated or unsaturated alicyclic hydrocarbon group, straight At least one selected from the group consisting of a divalent group containing at least one group selected from the group consisting of linear or branched saturated or unsaturated aliphatic hydrocarbon groups and heterocyclic groups. Containing a structural unit having a tetralin ring,
The polyester compound has a weight average molecular weight (Mw) of 1.0 × 10 ^{3 to} 8.0 × 10 ⁶ , a number average molecular weight (Mn) of 1.0 × 10 ^{3 to} 1.0 × 10 ⁶ , a glass transition temperature ( Tg) is 0 to 90 ° C.
The oxygen-absorbing resin composition is an oxygen-absorbing resin composition containing a transition metal catalyst in an amount of 0.001 part by weight or more and 0.015 part by weight or less as a transition metal amount with respect to 100 parts by weight of the polyester compound.   The oxygen-absorbing resin composition according to claim 1, wherein the transition metal catalyst contains at least one transition metal selected from the group consisting of manganese, iron, cobalt, nickel, and copper.   The oxygen-absorbing resin composition according to claim 1 or 2, wherein the shape of the oxygen-absorbing resin composition is at least one selected from the group consisting of pellets, powders, and flakes. The structural unit represented by the general formula (1) is represented by the following (5) to (7);
The oxygen-absorbing resin composition according to any one of claims 1 to 3, which is at least one selected from the group consisting of: