JP2018070828A - Polyamide resin and film using the same - Google Patents

Abstract

[Problem] To provide a polyamide resin having a small natural shrinkage rate and excellent heat shrinkage, and a film using the same. [Solution] The polyamide resin contains a repeating unit represented by formula (A), a repeating unit represented by formula (B), and a repeating unit represented by formula (C). It may further contain a repeating unit represented by formula (D). A film, which may be a stretched film, containing the polyamide resin. A packaging material containing the film. (A): -(CO-CO)-, (B): -(NH-R1-CO)-, (C): -(NH-R2-NH)-, (D): -(CO-R3-CO)- [R1 to R3 are substituted/unsubstituted hydrocarbon groups] [Selected Figure] None

Description

  The present invention relates to a polyamide resin and a film using the same.

  Polyamide resins are excellent in mechanical strength, thermal properties, chemical properties, and gas barrier properties, and are therefore used as food packaging materials such as retort foods. In recent years, with the expansion of these food packaging applications, the required characteristics are diversified and sophisticated.

  For processed meat products such as ham and sausage and aquatic food packaging applications, which are one of food packaging applications, the packaging material is shrunk by heating while maintaining thin and practical mechanical strength and gas barrier properties. Thus, there is a need for a polyamide film excellent in heat shrinkability that enables easy packaging of the contents.

  So far, polyamide resins and polyamide films that can improve the heat shrinkability of polyamide films have been disclosed. As a polyamide resin capable of improving heat shrinkability, a polyamide copolymer comprising ε-caprolactam, an aliphatic diamine such as hexamethylenediamine, and an aromatic dicarboxylic acid such as terephthalic acid or isophthalic acid is disclosed (for example, , See Patent Document 1).

JP 62-227626 A

  In order to wrap the contents, the polyamide film is required to have a smaller shrinkage rate (natural shrinkage rate) when left naturally. On the other hand, after packaging, in order to further improve the sterilization of the contents and the tightness of the contents, it is subjected to hot water shrinkage, but its hot water shrinkage ratio (excellent in heat shrinkability) and its film are provided. There is a need for polyamide resins that can be made.

  An object of the present invention is to provide a polyamide resin having a small natural shrinkage ratio and excellent heat shrinkability, and a film using the same.

The present invention is as follows.
[1]
A repeating unit represented by the following formula (A);
A repeating unit represented by the following formula (B);
[However, R ₁ represents a hydrocarbon group which may have a substituent. ]
A polyamide resin comprising a repeating unit represented by the following formula (C).
[However, R ₂ represents a hydrocarbon group which may have a substituent. R ₂ may be the same as or different from R _{1 in} formula (B). ]

[2]
Furthermore, the polyamide resin as described in [1] containing the repeating unit represented by a following formula (D).
[However, R ₃ represents a hydrocarbon group which may have a substituent. R ₃ is _{R 1,} it may be the same or different as _{R 2} of formula (C) of formula (B). ]

[3]
The polyamide resin according to [1] or [2], comprising at least two types of repeating units represented by the formula (B).

[4]
The polyamide resin according to any one of [1] to [3], comprising at least two types of repeating units represented by the formula (C).

[5]
In all units of polyamide resin,
0.005 to 25% by weight of the repeating unit represented by the formula (A),
0.05 to 99.97% by weight of the repeating unit represented by the formula (B),
The polyamide resin according to any one of [1] to [4], containing 0.02-49.99 wt% of the repeating unit represented by the formula (C).

[6]
The polyamide resin according to any one of [1] to [5], which includes a repeating unit in which R _{1 of the} repeating unit represented by the formula (B) is an alkylene group having 1 to 11 carbon atoms.

[7]
The polyamide resin according to any one of [1] to [6], including a repeating unit in which R _{3 of the} repeating unit represented by the formula (C) is an alkylene group having 1 to 12 carbon atoms.

[8]
A repeating unit in which R _{1 of the} repeating unit represented by the formula (B) is an alkylene group having 5 carbon atoms;
A repeating unit in which R _{1 of the} repeating unit represented by the formula (B) is an alkylene group having 11 carbon atoms;
The polyamide resin according to any one of [1] to [7].

[9]
A repeating unit in which R _{2 of the} repeating unit represented by the formula (C) is an alkylene group having 1 to 12 carbon atoms;
A repeating unit in which R _{3 of the} repeating unit represented by the formula (D) is an alkylene group having 1 to 10 carbon atoms;
The polyamide resin according to any one of [2] to [8].

[10]
A repeating unit in which R _{2 of the} repeating unit represented by the formula (C) is a C 6 alkylene group;
A repeating unit in which R _{2 of the} repeating unit represented by the formula (C) is a C 12 alkylene group;
A repeating unit in which R _{3 of the} repeating unit represented by the formula (D) is a C 4 alkylene group;
The polyamide resin according to any one of [2] to [9], comprising:

[11]
The film containing the polyamide resin of any one of [1]-[10].

[12]
A stretched film comprising the polyamide resin according to any one of [1] to [10].

[13]
A biaxially stretched film comprising the polyamide resin according to any one of [1] to [10].

[14]
The multilayer film containing the film as described in [11]-[13].

[15]
[11] A packaging material comprising the film according to [14].

  According to the present invention, it is possible to provide a polyamide resin having a small natural shrinkage ratio and excellent heat shrinkability and a film using the same.

[Polyamide resin]
The polyamide resin of the present invention includes a repeating unit represented by the formula (A), a repeating unit represented by the formula (B), and a repeating unit represented by the formula (C). Furthermore, a repeating unit represented by the formula (D) may be included.

[Repeating unit represented by formula (A)]

  From the viewpoint of reducing the natural shrinkage, the repeating unit represented by the formula (A) contained in all units of the polyamide resin is preferably contained in an amount of 0.005 to 25% by weight, and 0.007 to 14.32% by weight. It is more preferable to contain, it is more preferable to contain 0.007-7.16 weight%, It is especially preferable to contain 0.007-1.44 weight%, It contains 0.007-0.72 weight%. Most preferred.

  The repeating unit (A) is derived from an oxalic acid compound. The oxalic acid compound may be any compound as long as it forms an amide bond with the amino group of the diamine component, lactam component or aminocarboxylic acid component and can derive the unit represented by the above formula (A). Oxalic acid monoester or a salt thereof, or oxalic acid diester. From the viewpoint of suppressing side reactions in the polycondensation reaction, carbons such as oxalic acid diesters such as dimethyl oxalate, diethyl oxalate, di (n or iso) propyl oxalate, di (n, iso, sec or tert) butyl oxalate, and dihexyl oxalate An oxalic acid diester having an alkoxy group having 1 to 6 carbon atoms, an oxalic acid diester having a cycloalkoxy group having 3 to 6 carbon atoms such as dicyclohexyl oxalate, and an oxalic acid diaryl ester such as diphenyl oxalate are preferable. Dibutyl and diphenyl oxalate are more preferred, and dibutyl oxalate is more preferred.

[Repeating unit represented by formula (B)]
[However, R ₁ represents a hydrocarbon group which may have a substituent. ]

  The polyamide resin of the present invention preferably contains at least one type of repeating unit represented by formula (B), and at least two types from the viewpoint of increasing hot water shrinkage.

The number of carbon atoms in R ₁ is preferably 1 to 19, more preferably 1 to 11, and still more preferably 3 to 11.

When at least two types of repeating units represented by the formula (B) are included, R _{1 of the} repeating unit represented by the formula (B) is a repeating unit in which R ₁ is a hydrocarbon group having 1 to 7 carbon atoms and R _{1 1} preferably includes a repeating unit which is a hydrocarbon group having 8 to 19 carbon atoms, and R ₁ is a repeating unit which is a hydrocarbon group having 1 to 7 carbon atoms and R ₁ is a hydrocarbon group having 8 to 11 carbon atoms. It is more preferable that R ₁ is a repeating unit in which R ₁ is a hydrocarbon group having 3 to 7 carbon atoms and R ₁ is a repeating unit in which R ₁ is a hydrocarbon group having 8 to 11 carbon atoms. it is particularly preferred that the repeating units and R ₁ R ₁ is a hydrocarbon group having 5 carbon atoms containing a repeating unit is a hydrocarbon group of 11 carbon atoms. Moreover, at least 2 types of repeating unit represented by Formula (B) may be included at random, and you may include in the block form.

In the case where at least two types of repeating units represented by the formula (B) are included, a specific example is exemplified by the repeating unit in which R _{1 of the} repeating units represented by the formula (B) is a hydrocarbon group having 3 carbon atoms. R ₁ is a repeating unit in which the hydrocarbon group has 8 carbon atoms, the repeating unit represented by formula (B) is a repeating unit in which R ₁ is a hydrocarbon group having 3 carbon atoms, and R ₁ is a hydrocarbon having 9 carbon atoms. A repeating unit represented by formula (B), a repeating unit represented by formula (B) wherein R ₁ is a hydrocarbon group having 3 carbon atoms, and a repeating unit wherein R ₁ is a hydrocarbon group having 10 carbon atoms, formula (B repeating units R ₁ of repeating unit represented is a hydrocarbon group of repeating units and R ₁ is carbon 11 is a hydrocarbon group having 3 carbon atoms in), the repeating unit represented by the formula (B) R _A repeating unit in which ₁ is a hydrocarbon group having 5 carbon atoms and R ₁ is a repeating unit in which the hydrocarbon group has 8 carbon atoms, the repeating unit represented by formula (B) is a repeating unit in which R ₁ is a hydrocarbon group having 5 carbon atoms, and R ₁ is a hydrocarbon group having 9 carbon atoms. A repeating unit represented by formula (B) wherein R ₁ is a hydrocarbon group having 5 carbon atoms and R ₁ is a hydrocarbon group having 10 carbon atoms, formula (B) And a repeating unit in which R ₁ is a hydrocarbon group having 5 carbon atoms, a repeating unit in which R ₁ is a hydrocarbon group having 11 carbon atoms, and the like.

Among these, the repeating unit represented by the formula (B) is a repeating unit in which R ₁ is a hydrocarbon group having 5 carbon atoms and a repeating unit in which R ₁ is a hydrocarbon group having 8 carbon atoms, represented by the formula (B). repeating units repeating unit R ₁ R ₁ is a hydrocarbon group having 5 carbon atoms of the repeating units is a hydrocarbon group having 9 carbon atoms are, R ₁ of repeating unit represented by formula (B) is carbon A repeating unit that is a hydrocarbon group of number 5 and a repeating unit that R ₁ is a hydrocarbon group of carbon number 10 and a repeating unit that is represented by formula (B) wherein R ₁ is a hydrocarbon group of carbon number 5 It is preferable that the unit includes a repeating unit in which R ₁ is a hydrocarbon group having 11 carbon atoms, and the repeating unit in which R _{1 in the} repeating unit represented by the formula (B) is a hydrocarbon group having 5 carbon atoms and R Including repeating units in which ₁ is a hydrocarbon group having 11 carbon atoms Is more preferable.

  When at least two types of repeating units represented by the formula (B) are included, the content ratio of each repeating unit can be set to, for example, 1 / 99-99 / 1.

Examples of the hydrocarbon group represented by R ₁ in the formula (B) include an alkylene group and an arylene group. R ₁ may be composed of one type selected from these groups, or may be composed of a combination of two or more types.

  Examples of the alkylene group include a linear alkylene group, a branched alkylene group, a cycloalkylene group, and an alicyclic alkylene group.

  As a linear alkylene group, a C1-C19 linear alkylene group is preferable, A C1-C11 linear alkylene group is more preferable, for example, a propylene group, a pentylene group, a hexylene group, a heptylene group , Nonylene group, decylene group, undecylene group and the like. Among these, a linear alkylene group having 1 to 7 carbon atoms and 8 to 11 carbon atoms is more preferable, and a linear alkylene group having 5 and 11 carbon atoms is particularly preferable.

  The content of the repeating unit represented by the formula (B) contained in all the units of the polyamide resin is preferably 0.05 to 99.97% by weight from the viewpoint of increasing hot water shrinkage. 12-99.97% by weight is more preferable, 78.56-99.97% by weight is more preferable, 95.71-99.97% by weight is particularly preferable, and 97.85- The content is most preferably 99.97% by weight.

  The repeating unit (B) is derived from lactam and / or aminocarboxylic acid. Examples of the lactam include ε-caprolactam, ω-enantolactam, ω-undecalactam, ω-dodecalactam, 2-pyrrolidone, and the like. At least one selected from the group consisting of these is preferable, and ε-caprolactam and More preferred is ω-dodecalactam.

  Examples of the aminocarboxylic acid include 6-aminocaproic acid, 7-aminoheptanoic acid, 8-aminooctanoic acid, 10-aminocapric acid, 11-aminoundecanoic acid, 12-aminododecanoic acid, and the like. At least one selected is preferable, and 6-aminocaproic acid and / or 12-aminododecanoic acid is more preferable.

  These lactams and aminocarboxylic acids may be used alone or in appropriate combination of two or more. When lactam and aminocarboxylic acid are used in combination, they can be mixed and used at an arbitrary ratio.

Among these, R ₁ is preferably an alkylene group having 1 to 11 carbon atoms, more preferably an alkylene group having 1 to 7 carbon atoms and 8 to 11 carbon atoms, and further preferably an alkylene group having 5 carbon atoms and 11 carbon atoms. preferable.

[Repeating unit represented by formula (C)]
[However, R ₂ represents a hydrocarbon group which may have a substituent. R ₂ may be the same as or different from R _{1 in} formula (B). ]

  The polyamide resin of the present invention contains at least one type of repeating unit represented by the formula (C), but preferably contains at least two types from the viewpoint of increasing hot water shrinkage.

The number of carbon atoms in R ₂ is preferably 1-20, more preferably 1-12, and even more preferably 4-12.

When at least two types of repeating units represented by the formula (C) are included, R _{2 of the} repeating unit represented by the formula (C) is a repeating unit in which R ₂ is a hydrocarbon group having 1 to 8 carbon atoms and R _{2 1} preferably includes a repeating unit which is a hydrocarbon group having 9 to 20 carbon atoms, R ₂ is a repeating unit which is a hydrocarbon group having 1 to 8 carbon atoms, and R ₁ is a hydrocarbon group having 9 to 12 carbon atoms. It is more preferable that R ₂ is a repeating unit in which R ₂ is a hydrocarbon group having 4 to 8 carbon atoms and R ₁ is a repeating unit in which R ₁ is a hydrocarbon group having 9 to 12 carbon atoms. It is particularly preferable that R _{2 includes} a repeating unit which is a hydrocarbon group having 6 carbon atoms and a repeating unit where R ₁ is a hydrocarbon group having 12 carbon atoms. Moreover, at least 2 types of repeating unit represented by Formula (C) may be included at random, and you may include in the block form.

In the case where at least two types of repeating units represented by the formula (C) are included, a specific example is illustrated as a repeating unit in which R _{2 of the} repeating units represented by the formula (C) is a hydrocarbon group having 4 carbon atoms. R ₂ is a repeating unit in which the hydrocarbon group has 9 carbon atoms, a repeating unit represented by the formula (C), wherein R ₂ is a hydrocarbon group having 4 carbon atoms, and R ₂ is a hydrocarbon having 10 carbon atoms. A repeating unit represented by formula (C), a repeating unit represented by formula (C) wherein R ₂ is a hydrocarbon group having 4 carbon atoms, and a repeating unit wherein R ₂ is a hydrocarbon group having 11 carbon atoms, formula (C ) In which the repeating unit R ₂ is a hydrocarbon group having 4 carbon atoms, the repeating unit in which R ₂ is a hydrocarbon group having 12 carbon atoms, and the repeating unit R represented by the formula (C) a repeating unit ₂ is a hydrocarbon group of 6 carbon atoms ₂ repeating units is a hydrocarbon group having 9 carbon atoms, a hydrocarbon group of repeating units and R ₂ is 10 carbon atoms R ₂ in the repeating unit represented by formula (C) is a hydrocarbon group of 6 carbon atoms A repeating unit represented by formula (C), a repeating unit in which R ₂ is a hydrocarbon group having 6 carbon atoms, and a repeating unit in which R ₂ is a hydrocarbon group having 11 carbon atoms, formula (C) And a repeating unit in which R ₂ is a hydrocarbon group having 6 carbon atoms, a repeating unit in which R ₂ is a hydrocarbon group having 12 carbon atoms, and the like.

Among these, the repeating unit represented by the formula (C) is a repeating unit in which R ₂ is a hydrocarbon group having 6 carbon atoms and the repeating unit in which R ₂ is a hydrocarbon group having 9 carbon atoms, represented by the formula (C). repeating units repeating unit R ₂ R ₂ in the repeating units is a hydrocarbon group having 6 carbon atoms is a hydrocarbon group having 10 carbon atoms being, R ₂ carbon of the repeating unit represented by formula (C) repeating the repeating units and the repeating units R ₂ is a hydrocarbon group having 11 carbon atoms is a hydrocarbon group having 6, R ₂ in the repeating unit represented by formula (C) is a hydrocarbon group of 6 carbon atoms Preferably, the unit includes a repeating unit in which R ₂ is a hydrocarbon group having 12 carbon atoms, and the repeating unit in which R _{2 in the} repeating unit represented by the formula (C) is a hydrocarbon group having 6 carbon atoms and R Repeating unit ₂ is a hydrocarbon group having 12 carbon atoms, It is more preferable to contain.

  When at least two types of repeating units represented by the formula (C) are included, the content ratio of each repeating unit can be set to, for example, 1 / 99-99 / 1.

Examples of the hydrocarbon group represented by R ₂ in the formula (C) include an alkylene group and an arylene group. R ₂ may be composed of one type selected from these groups, or may be composed of a combination of two or more types.

  Examples of the alkylene group include a linear alkylene group, a branched alkylene group, a cycloalkylene group, and an alicyclic alkylene group.

  As the linear alkylene group, a linear alkylene group having 1 to 20 carbon atoms is preferable, and a linear alkylene group having 1 to 12 carbon atoms is more preferable. For example, a methylene group, an ethylene group, a propylene group, 2, Examples include 2-propylene group, butylene group, hexylene group, nonylene group, undecylene group, dodecylene group and the like. Among these, a linear alkylene group having 1 to 8 carbon atoms and 9 to 12 carbon atoms is more preferable, and a linear alkylene group having 6 to 12 carbon atoms is particularly preferable.

  As the branched alkylene group, a branched alkylene group having 1 to 20 carbon atoms is preferable, and a branched alkylene group having 1 to 12 carbon atoms is more preferable. For example, 1-butyl-1,2-ethylene group, 1,1 -Dimethyl-1,4-butylene group, 1-ethyl-1,4-butylene group, 1,2-dimethyl-1,4-butylene group, 1,3-dimethyl-1,4-butylene group, 1,4 -Dimethyl-1,4-butylene group, 2,3-dimethyl-1,4-butylene group, 2-methyl-1,5-pentylene group, 3-methyl-1,5-pentylene group, 2,2-dimethyl -1,6-hexylene group, 2,5-dimethyl-1,6-hexylene group, 2,4-dimethyl-1,6-hexylene group, 3,3-dimethyl-1,6-hexylene group, 2,2 , 4-trimethyl-1,6-hexylene group, 2,4 4-trimethyl-1,6-hexylene group, 2,4-diethyl-1,6-hexylene group, 2-methyl-1,7-heptylene group, 2,2-dimethyl-1,7-heptylene group, 2, 3-dimethyl-1,7-heptylene group, 2,4-dimethyl-1,7-heptylene group, 2,5-dimethyl-1,7-heptylene group, 2-methyl-1,8-octylene group, 3- Methyl-1,8-octylene group, 4-methyl-1,8-octylene group, 1,4-dimethyl-1,8-octylene group, 2,4-dimethyl-1,8-octylene group, 3,4- Dimethyl-1,8-octylene group, 4,5-dimethyl-1,8-octylene group, 2,2-dimethyl-1,8-octylene group, 3,3-dimethyl-1,8-octylene group, 4, 4-dimethyl-1,8-octylene group, 5-methyl 1,9 nonylene group, and the like. Among these, a branched alkylene group having 1 to 8 carbon atoms and 9 to 12 carbon atoms is more preferable, and a branched alkylene group having 6 and 12 carbon atoms is particularly preferable.

  The cycloalkylene group is preferably a cycloalkylene group having 1 to 20 carbon atoms, more preferably a cycloalkylene group having 1 to 12 carbon atoms, such as a cyclopropylene group, 1,2-cyclohexylene group, 1,3-cyclohexylene. Silene group, 1,4-cyclohexylene group, 1,4- (3-methyl) -cyclohexylene group, 1,4- (3-ethyl) -cyclohexylene group, 1,4- (3,5-dimethyl ) -Cyclohexylene group, 1,4- (3,5-diethyl) -cyclohexylene group, 1,4- (3-methyl-5-ethyl) -cyclohexylene group, 1- (3-methylene) -3,5,5-trimethylcyclohexylene group, 5- (2,2,4-trimethyl)-(1-methylene) -cyclopentylene group, 5- (1,3,3-trimethyl)-(1- Methylene) Examples include a chloroxylene group. Among these, a cycloalkylene group having 1 to 8 carbon atoms and 9 to 12 carbon atoms is more preferable, and a cycloalkylene group having 6 and 12 carbon atoms is particularly preferable.

  The alicyclic alkylene group is preferably an alicyclic alkylene group having 1 to 20 carbon atoms, more preferably an alicyclic alkylene group having 1 to 12 carbon atoms, such as a cyclopropylmethine group, a cyclobutylmethine group, a cyclopentylmethine group, and the like. Is mentioned. Among these, an alicyclic alkylene group having 1 to 8 carbon atoms and 9 to 12 carbon atoms is more preferable, and an alicyclic alkylene group having 6 and 12 carbon atoms is particularly preferable.

  Examples of the arylene group include a phenylene group, a naphthylene group, a tolylene group, an ethylphenylene group, a dimethylphenylene group, a diethylphenylene group, and a methylethylphenylene group. Examples thereof include a p-phenylene group, an m-phenylene group, and 1,4. -Naphthylene group, 1,8-naphthylene group, 2,3-naphthylene group, 2,6-naphthylene group, 2,4-tolylene group, 2,5-tolylene group, 2,6-tolylene group, 1,4- (3-ethyl) phenylene group, 1,4- (3,5-dimethyl) phenylene group, 1,4- (3,5-diethyl) phenylene group, 1,4- (3-methyl-5-ethyl) phenylene Groups and the like.

Two or more kinds of alkylene groups and arylene groups may be combined to form R ₂ of the repeating unit represented by the formula (C). Examples include a combination of two types of alkylene groups, a combination of three types of alkylene groups, a combination of an alkylene group and an arylene group, and the like.

  The combination of two types of alkylene groups includes a combination of a linear alkylene group and a cycloalkylene group, a combination of two cycloalkylene groups, a combination of two alicyclic alkylene groups, and the like. For example, a methylene group and 1- (3- Methylene) -3,5,5-trimethylcyclohexylene group, methylene group and 5- (2,2,4-trimethyl)-(1-methylene) -cyclopentylene group, methylene group and 5- ( And a combination of 1,3,3-trimethyl)-(1-methylene) -cyclohexylene groups.

  As a combination of three types of alkylene groups, a combination of a linear alkylene group, a cycloalkylene group, and a linear alkylene group, a combination of a cycloalkylene group, a linear alkylene group, and a cycloalkylene group, a combination of three cycloalkylene groups, There are combinations of three alicyclic alkylene groups.

  As a combination of a linear alkylene group, a cycloalkylene group and a linear alkylene group, for example, a combination of a methylene group, a 1,3-cyclohexylene group and a methylene group, a methylene group, a 1,4-cyclohexylene group and a methylene group And the like.

  As a combination of a cycloalkylene group, a linear alkylene group and a cycloalkylene group, for example, a combination of a 1,4-cyclohexylene group, a methylene group and a 1,4-cyclohexylene group, a 1,4-cyclohexylene group and a propylene group And 1,4-cyclohexylene group, 1,4- (3-methyl) -cyclohexylene group, methylene group and 1,4- (3-methyl) -cyclohexylene group, 1,4- (3 -Methyl) -cyclohexylene group, propylene group and 1,4- (3-methyl) -cyclohexylene group, 1,4- (3-ethyl) -cyclohexylene group, methylene group and 1,4- ( Combination of 3-ethyl) -cyclohexylene group, 1,4- (3-ethyl) -cyclohexylene group, propylene group and 1,4- (3-ethyl) A combination of cyclohexylene group, 1,4- (3,5-dimethyl) -cyclohexylene group, methylene group and 1,4- (3,5-dimethyl) -cyclohexylene group, 1,4- Combination of (3,5-dimethyl) -cyclohexylene group, propylene group and 1,4- (3,5-dimethyl) -cyclohexylene group, 1,4- (3,5-diethyl) -cyclohexylene Group, methylene group and 1,4- (3,5-diethyl) -cyclohexylene group, 1,4- (3,5-diethyl) -cyclohexylene group, propylene group and 1,4- (3 , 5-diethyl) -cyclohexylene group, 1,4- (3-methyl-5-ethyl) -cyclohexylene group, methylene group and 1,4- (3-methyl-5-ethyl) -cyclo Hexylene group combination , 1,4- (3-methyl-5-ethyl) - xylene group and propylene group cyclohex 1,4 (3-methyl-5-ethyl) - combination of cyclohexylene group and the like.

  Examples of the combination of an alkylene group and an arylene group include combinations such as those of formula (1) and formula (2).

(In the formula, X and Y represent an alkylene group. X and Y may be the same or different. Ar represents an arylene group.)

(In the formula, Z represents an alkylene group. Ar represents an arylene group.)
Examples of the combination of formula (1) include (X, Ar, Y) = (methylene group, p-phenylene group, methylene group), (methylene group, m-phenylene group, methylene group) and the like.

  As a combination of formula (2), for example, (Ar, Z, Ar) = (p-phenylene group, methylene group, p-phenylene group), (2,5-tolylene group, methylene group, 2,5-tolylene group) (1,4- (3-ethyl) phenylene group, methylene group, 1,4- (3-ethyl) phenylene group), (1,4- (3,5-dimethyl) phenylene group, methylene group, 1, 4- (3,5-dimethyl) phenylene group), (1,4- (3,5-diethyl) phenylene group, methylene group, 1,4- (3,5-diethyl) phenylene group), (1,4 -(3-methyl-5-ethyl) phenylene group, methylene group, 1,4- (3-methyl-5-ethyl) phenylene group), (m-phenylene group, 2,2-propylene group, m-phenylene group) ), (P-phenylene group, 2,2-propylene group, -Phenylene group), (2,5-tolylene group, 2,2-propylene group, 2,5-tolylene group), (1,4- (3-ethyl) phenylene group, 2,2-propylene group, 1, 4- (3-ethyl) phenylene group), (1,4- (3,5-dimethyl) phenylene group, 2,2-propylene group, 1,4- (3,5-dimethyl) phenylene group), (1 , 4- (3,5-diethyl) phenylene group, 2,2-propylene group, 1,4- (3,5-diethyl) phenylene group), (1,4- (3-methyl-5-ethyl) phenylene) Group, 2,2-propylene group, 1,4- (3-methyl-5-ethyl) phenylene group) and the like.

Among, R ₂ is preferably an alkylene group having 1 to 12 carbon atoms, more preferably an alkylene group having 9-12 1-8 and carbon atoms, still an alkylene group having 6 to 12 carbon atoms atoms preferable.

  The content of the repeating unit represented by the formula (C) contained in all the units of the polyamide resin is preferably 0.02 to 49.99% by weight from the viewpoint of increasing the hot water shrinkage. The content is more preferably 02-30.44% by weight, still more preferably 0.02-15.22% by weight, particularly preferably 0.02-3.05% by weight, The content is most preferably 1.53% by weight.

  The repeating unit (C) is derived from diamine. Examples of the diamine include linear aliphatic diamines such as ethylene diamine, tetramethylene diamine, hexamethylene diamine, nonamethylene diamine, undecamethylene diamine, and dodecamethylene diamine; 1-butyl-1,2-ethanediamine, 1,1- Dimethyl-1,4-butanediamine, 1-ethyl-1,4-butanediamine, 1,2-dimethyl-1,4-butanediamine, 1,3-dimethyl-1,4-butanediamine, 1,4- Dimethyl-1,4-butanediamine, 2,3-dimethyl-1,4-butanediamine, 2-methyl-1,5-pentanediamine, 3-methyl-1,5-pentanediamine, 2,2-dimethyl- 1,6-hexanediamine, 2,5-dimethyl-1,6-hexanediamine, 2,4-dimethyl-1,6-hexanedia 3,3-dimethyl-1,6-hexanediamine, 2,2,4-trimethyl-1,6-hexanediamine, 2,4,4-trimethyl-1,6-hexanediamine, 2,4-diethyl -1,6-hexanediamine, 2-methyl-1,7-heptanediamine, 2,2-dimethyl-1,7-heptanediamine, 2,3-dimethyl-1,7-heptanediamine, 2,4-dimethyl -1,7-heptanediamine, 2,5-dimethyl-1,7-heptanediamine, 2-methyl-1,8-octanediamine, 3-methyl-1,8-octanediamine, 4-methyl-1,8 -Octanediamine, 1,4-dimethyl-1,8-octanediamine, 2,4-dimethyl-1,8-octanediamine, 3,4-dimethyl-1,8-octanediamine, 4,5-dimethyl 1,8-octanediamine, 2,2-dimethyl-1,8-octanediamine, 3,3-dimethyl-1,8-octanediamine, 4,4-dimethyl-1,8-octanediamine, 5- Branched aliphatic diamines such as methyl-1,9-nonanediamine; p-phenylenediamine, m-phenylenediamine, p-xylylenediamine, m-xylylenediamine, 2,4-tolylenediamine, 2,6-triene Range amine, 1,4-diaminonaphthalene, 1,8-diaminonaphthalene, 2,3-diaminonaphthalene, 2,6-diaminonaphthalene, 3,3′-diaminodiphenylmethane, 3,4′-diaminodiphenylmethane, 4,4 '-Diaminodiphenylmethane, 4,4'-diamino-3,3'-dimethyldiphenylmethane, 4,4'-diamino -3,3'-diethyldiphenylmethane, 4,4'-diamino-3,3 ', 5,5'-tetramethyldiphenylmethane, 4,4'-diamino-3,3', 5,5'-tetraethyldiphenylmethane, 4,4′-diamino-3,3′-dimethyl-5,5′-diethyldiphenylmethane, 2,2′-bis (3-aminophenyl) propane, 2,2′-bis (4-aminophenyl) propane, 2,2′-bis (4-amino-3-methylphenyl) propane, 2,2′-bis (4-amino-3-ethylphenyl) propane, 2,2′-bis (4-amino-3,5) -Dimethylphenyl) propane, 2,2'-bis (4-amino-3,5-diethylphenyl) propane, 2,2'-bis (4-amino-3-methyl-5-ethylphenyl) propane, etc. Group diamine; cyclopropanediamine, cyclopropyldiaminomethyl, cyclobutyldiaminomethyl, cyclopentyldiaminomethyl, bis (4-aminocyclohexyl) methane, bis (4-aminocyclohexyl) propane, 1,2-cyclohexanediamine, 1,3- Cycloaliphatic diamines such as cyclohexanediamine, 1,4-cyclohexanediamine, 1,3-bisaminomethylcyclohexane, 1,4-bisaminomethylcyclohexane; 1-amino-3-aminomethyl-3,5,5-trimethyl Cyclohexane (hereinafter also referred to as “isophoronediamine”). ), 5-amino-2,2,4-trimethyl-1-cyclopentanemethylamine, 5-amino-1,3,3-trimethylcyclohexanemethylamine, bis (4-amino-3-methylcyclohexyl) methane, bis (4-amino-3-methylcyclohexyl) propane, bis (4-amino-3-ethylcyclohexyl) methane, bis (4-amino-3,5-dimethylcyclohexyl) methane, bis (4-amino-3,5- Dimethylcyclohexyl) propane, bis (4-amino-3-ethylcyclohexyl) methane, bis (4-amino-3-ethylcyclohexyl) propane, bis (4-amino-3,5-diethylcyclohexyl) methane, bis (4- Amino-3,5-diethylcyclohexyl) propane, bis (4-amino-3-methyl-5) Branched alicyclic diamines such as ethylcyclohexyl) methane, bis (4-amino-3-methyl-5-ethylcyclohexyl) propane, and the like, preferably at least one selected from the group consisting of these, linear More preferred is at least one selected from aliphatic diamines. These diamines may be used alone or in combination of two or more.

[Repeating unit represented by formula (D)]
[However, R ₃ represents a hydrocarbon group which may have a substituent. R ₃ is _{R 1,} it may be the same or different as _{R 2} of formula (C) of formula (B). ]

  The polyamide resin of the present invention contains at least one type of repeating unit represented by the formula (D), but may contain two or more types.

Examples of the hydrocarbon group represented by R ₃ in the formula (D) include an alkylene group and an arylene group. R ₃ may be composed of one type selected from these groups, or may be composed of a combination of two or more types.

  Examples of the alkylene group include a linear alkylene group, a branched alkylene group, a cycloalkylene group, and an alicyclic alkylene group.

  As a linear alkylene group, a C1-C18 linear alkylene group is preferable, for example, a methylene group, butylene group, pentylene group, hexylene group, heptylene group, octylene group, nonylene group, decylene group, undecylene. Group, dodecylene group, tridecylene group, tetradecylene group, hexadecylene group, octadecylene group and the like. Among these, a linear alkylene group having 1 to 10 carbon atoms is more preferable, and a linear alkylene group having 4 carbon atoms is more preferable.

  As the branched alkylene group, a branched alkylene group having 1 to 20 carbon atoms is preferable. For example, a dimethylmethylene group, a 1,1-dimethylethylene group, a 1,1-dimethylpropylene group, a 1-methylbutylene group, 2- Methylbutylene group, trimethylbutylene group, 1-butylhexylene group, 1,2-dibutylethylene group, 7-ethylhexadecylene group, 7,12-dimethyloctadecylene group, 1-octylnonylene group, 1- Nonyloctylene group etc. are mentioned. Among these, a branched alkylene group having 1 to 10 carbon atoms is more preferable, and a branched alkylene group having 4 carbon atoms is more preferable.

  The cycloalkylene group is preferably a cycloalkylene group having 1 to 20 carbon atoms, more preferably a cycloalkylene group having 1 to 10 carbon atoms, such as a 1,2-cyclohexylene group, 1,3-cyclohexylene group, 1 , 4-cyclohexylene group and the like. Among these, a cycloalkylene group having 4 carbon atoms is more preferable.

  The alicyclic alkylene group is preferably an alicyclic alkylene group having 1 to 20 carbon atoms, more preferably an alicyclic alkylene group having 1 to 10 carbon atoms, and further preferably an alicyclic alkylene group having 4 carbon atoms.

  Examples of the arylene group include a phenylene group, a naphthylene group, a tolylene group, an ethylphenylene group, a dimethylphenylene group, a diethylphenylene group, a methylethylphenylene group, and a benzylphenylene group, and examples thereof include an m-phenylene group and a p-phenylene group. 1,4-naphthylene group, 1,8-naphthylene group, 2,6-naphthylene group, 2,7-naphthylene group, 2-benzyl-1,5-phenylene group and the like.

Two or more alkylene groups or arylene groups may be combined to form R ₃ of the repeating unit represented by the formula (D). Examples include a combination of two types of alkylene groups, a combination of three types of alkylene groups, a combination of an alkylene group and an arylene group, and the like.

  Examples of combinations of three types of alkylene groups include a combination of a cycloalkylene group, an alkylene group, and a cycloalkylene group, such as a combination of a 1,4-cyclohexylene group, a methylene group, and a 1,4-cyclohexylene group. Is mentioned.

  Examples of the combination of an alkylene group and an arylene group include combinations such as formula (3) and formula (4).

(In the formula, Ar represents an arylene group.)

(In the formula, Ar represents an arylene group. X ′ represents an alkylene group.)
Examples of the combination of formula (3) include (Ar, Ar) = (p-phenylene group, p-phenylene group).

  As combinations of the formula (4), for example, (Ar, X ′, Ar) = (m-phenylene group, methylene group, m-phenylene group), (m-phenylene group, methylene group, p-phenylene group), (p -Phenylene group, methylene group, p-phenylene group) and the like.

Among these, R ₃ is preferably an alkylene group having 1 to 10 carbon atoms, and more preferably an alkylene group having 4 carbon atoms.

  The content of the repeating unit represented by the formula (D) contained in all the units of the polyamide resin is preferably 0 to 49.95% by weight from the viewpoint of increasing hot water shrinkage, and is preferably 0 to 30% by weight. % Content is more preferable, and 0-10% by weight is more preferable.

  The repeating unit (D) is derived from a dicarboxylic acid other than oxalic acid. Examples of dicarboxylic acids other than oxalic acid include adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid, tetradecanedioic acid, pentadecanedioic acid, hexadecanedioic acid, octadecanedoic acid Linear aliphatic dicarboxylic acids such as dionic acid and eicosandioic acid; dimethylmalonic acid, 3,3-dimethylsuccinic acid, 2,2-dimethylglutaric acid, 2-methyladipic acid, 3-methyladipic acid, trimethyl Adipic acid, 2-butyloctadionic acid, 2,3-dibutylbutanedioic acid, 8-ethyloctadecanedioic acid, 8,13-dimethyleicosadioic acid, 2-octylundecanedioic acid, 2-nonyldecanedioic acid, etc. Branched aliphatic carboxylic acids; isophthalic acid, terephthalic acid Acid, 1,4-naphthalenedicarboxylic acid, 1,8-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 4,4'-biphenyldicarboxylic acid, diphenylmethane-2,4-dicarboxylic acid Acids, aromatic dicarboxylic acids such as diphenylmethane-3,3′-dicarboxylic acid, diphenylmethane-3,4′-dicarboxylic acid, diphenylmethane-4,4′-dicarboxylic acid; 1,2-cyclohexanedicarboxylic acid, 1,3- Examples include alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, and dicyclohexylmethane-4,4′-dicarboxylic acid. At least one selected from the group consisting of these is preferable, and linear More preferred is at least one selected from aliphatic dicarboxylic acids There. These dicarboxylic acids may be used alone or in combination of two or more.

[Additive]
In the polyamide resin, as long as the effect of the present invention is not hindered, the polyamide resin other than the present invention, the thermoplastic resin other than the polyamide resin, the thermal stabilizer, the ultraviolet absorber, the light stabilizer, the antioxidant, the antistatic agent, Tackifiers, sealant improvers, antifogging agents, mold release agents, impact resistance improvers, plasticizers, pigments, dyes, fragrances, reinforcing materials, and the like can be added.

[Production method of polyamide resin]
The production of the polyamide resin of the present invention can be carried out batchwise or continuously. A batch reactor, a single tank or multi-tank continuous reactor, a tubular continuous reactor, a single screw kneading extruder, a twin screw kneading machine. A known polyamide production apparatus such as a kneading reaction extruder such as an extruder can be used. As the polymerization method, known methods such as melt polymerization, solution polymerization and solid phase polymerization can be used. These polymerization methods can be used alone or in appropriate combination.

  The method for producing the polyamide resin of the present invention includes, for example, charging lactam and / or aminocarboxylic acid, diamine and / or dicarboxylic acid, and water into a pressure-resistant container, and adding it in a temperature range of 200 to 350 ° C. in a sealed state. After polycondensation under pressure, the target polyamide resin can be produced by lowering the pressure and continuing the polycondensation reaction in the temperature range of 200 to 350 ° C. under atmospheric pressure or reduced pressure to increase the molecular weight. . In this case, the diamine and / or dicarboxylic acid is formed by reacting an approximately equimolar oxalic acid compound with lactam or aminocarboxylic acid to form an oxamide bond and diamine, or reacting an oxalic acid compound with diamine to form an oxamide bond. The formed diamine and dicarboxylic acid are mixed with water, alcohol, etc. and dissolved, and then a nylon salt is formed, and the solution is in the state of a solution, concentrated solution, or solid nylon salt obtained by recrystallization. You may charge as. Also, instead of diamine and / or dicarboxylic acid, dicarboxylic acid and diamine, or oxalic acid compound and diamine, which are formed by reacting approximately equimolar oxalic acid compound with lactam or aminocarboxylic acid to form an oxamide bond, are reacted with oxamide. The diamine and dicarboxylic acid that have formed a bond may be charged in a pressure vessel as they are. For example, a diamine constituting a unit having no oxamide bond and a dicarboxylic acid may be charged as an equimolar salt thereof, and a diamine and a dicarboxylic acid forming a unit having an oxamide bond may be directly charged in a pressure vessel. An equimolar mixture of approximately equimolar diamine and dicarboxylic acid substantially corresponds to an equimolar salt.

  The water used in the method for producing a polyamide resin of the present invention is preferably ion exchange water from which oxygen has been removed, distilled water, etc., and the amount used is, for example, 100 parts by weight of the raw material constituting the polyamide resin. 1 to 150 parts by weight.

  When producing the polyamide resin of the present invention, if necessary, phosphorous compounds such as phosphoric acid, phosphorous acid, hypophosphorous acid, polyphosphoric acid and alkali metal salts thereof are added to promote polymerization and prevent oxidation. be able to. The addition amount of these phosphorus compounds is usually 50 to 3,000 ppm with respect to the polyamide resin to be obtained. In addition, monoamines such as laurylamine and stearylamine; diamines such as hexamethylenediamine and metaxylylenediamine; monocarboxylic acids such as acetic acid, stearic acid, and benzoic acid; for molecular weight adjustment and stabilization of melt viscosity during molding processing; A polyamide resin may be produced by adding at least one molecular weight regulator selected from the group consisting of dicarboxylic acids such as adipic acid, isophthalic acid, and terephthalic acid. One type of these molecular weight regulators may be added, or two or more types may be added in appropriate combination. When a molecular weight regulator is used, the amount used varies depending on the reactivity of the molecular weight regulator and the polymerization conditions, but the final viscosity of the polyamide to be obtained is in the range of 1.5 to 5.0. As appropriate.

  The high molecular weight polyamide resin is usually extracted from the reaction vessel in a molten state, cooled with water, and then processed into a pellet. When the polyamide resin containing a large amount of unreacted monomer such as nylon 6 is a pellet whose main component is a pellet, it is preferably used for film production after removing the unreacted monomer by hot water washing or the like.

[Method for confirming the structure of polyamide resin]
The structure of the polyamide resin can be confirmed by ¹ H-NMR measurement. For example, the measurement conditions of ¹ H-NMR are as follows.
・ Model used: Bruker Biospin AVANCE500
・ Solvent: Bisulfuric acid ・ Accumulated times: 1024 times

[Confirmation method of content of each repeating unit in polyamide resin]
The content of each repeating unit in the polyamide resin can be confirmed by ¹ H-NMR measurement and ¹² C-NMR measurement. For example, each measurement condition is as follows.
^<1 H-NMR measurement>
・ Model used: Bruker Biospin AVANCE500
-Solvent: Bisulfuric acid-Number of integration: 1024 times < ¹² C-NMR measurement>
・ Model used: Bruker Biospin AVANCE500
・ Solvent: Bisulfuric acid ・ Accumulated times: 4096 times

[Molecular weight of polyamide resin]
The molecular weight of the polyamide resin of the present invention is based on JIS K-6920, 1 g of polyamide resin is dissolved in 100 ml of 96% concentrated sulfuric acid, and the relative viscosity (ηr) measured at 25 ° C. is in the range of 1.5 to 5.0, Preferably it is the range of 2.0-4.5. In addition, there is no special restriction | limiting in the kind of terminal group of the polyamide resin of this invention, its concentration, and molecular weight distribution.

[the film]
The polyamide resin of the present invention can be suitably used for film production. That is, this invention includes the use of the polyamide resin of this invention in manufacture of the film containing the polyamide resin of this invention, and the film containing the polyamide resin of this invention.

  The method for producing a film from the polyamide resin of the present invention includes a known film production method, for example, a production method such as a T-die method using a melt extruder, an inflation method, a tubular method, a solvent casting method, or a hot press method. Can be applied. The melting temperature of the polyamide in the method using the melt extruder is, for example, from the melting point of the polyamide to be used to 320 ° C. or less.

  The film containing the polyamide resin of the present invention may be a stretched film. That is, it is a stretched film containing the polyamide resin of the present invention. The stretched film can be produced, for example, by stretching a film containing the polyamide resin of the present invention, and the present invention includes the polyamide resin of the present invention and / or the polyamide resin of the present invention in the production of a stretched film of polyamide resin. Includes the use of film. The film containing the polyamide resin of the present invention may be a biaxially stretched film. That is, it is a biaxially stretched film containing the polyamide resin of the present invention. The biaxially stretched film can be produced, for example, by stretching a film containing the polyamide resin of the present invention, and the present invention is a polyamide resin of the present invention and / or of the present invention in the production of a biaxially stretched film of polyamide resin. Includes the use of a film comprising a polyamide resin.

  The stretching may be at least a uniaxial direction, and a uniaxial stretching method, a simultaneous biaxial stretching method, a sequential biaxial stretching method, or the like can be appropriately selected according to the intended use of the film. In particular, when producing a film by the sequential biaxial stretching method, after adding a lubricant such as calcium stearate, bisamide compound, silica, talc, slip agent, nucleating agent and the like to the polyamide resin, a resin composition is obtained. The resin composition is melt-extruded by an extruder equipped with a T die to form an unstretched film. The unstretched film may be continuously stretched in a continuous process, or may be stretched after being wound up. Stretching is performed at a temperature equal to or higher than the glass transition temperature (hereinafter referred to as Tg) of the polyamide resin used. The first stage of sequential biaxial stretching (primary stretching) is stretched in the temperature direction of Tg or more (Tg + 50) ° C., preferably 2 to 5 times, preferably 2.5 to 4 times in the film extrusion direction. Next, the second-stage stretching (secondary stretching) performed in a direction perpendicular to the film extrusion direction is the same temperature as or slightly higher than the primary stretching, and the stretching ratio is 2 to 5 times, preferably 2.5 to 4 times. Stretched. Then, a biaxially stretched film is sequentially manufactured through a process of heat setting at a temperature of 150 ° C. or higher.

[Multilayer film]
Two or more films containing the polyamide resin of the present invention may be laminated to form a multilayer film, or one or more films containing the polyamide resin of the present invention and one or more films containing other resins may be laminated to form a multilayer film. It is also good.

  Examples of other resins include polyethylene (PE), polypropylene (PP), polyolefin (PO), polycarbonate (PC), epoxy resin (EP), polyester, polyamide elastomer (PAE), polyvinyl alcohol (PVA), and ethylene vinyl. Examples include alcohol (EVOH), ethylene vinyl acetate (EVA), ethylene methyl methacrylate (EMMA), ethylene ethyl acrylate (EEA), ethylene bis stearic acid (EBS), styrene ethylene butylene styrene copolymer (SEBS), and silicone resin. It is done.

[Packaging materials]
A packaging material can also be obtained by using a film or a multilayer film containing the polyamide resin of the present invention.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention concretely, unless this invention exceeds the summary, it does not receive any limitation by the following examples. In addition, the measured value shown in the Example and the comparative example was measured with the following method.

(1) Measurement of ηr (relative viscosity) of polyamide resin In accordance with JIS K-6920, 1 g of polyamide resin was dissolved in 100 ml of 96% concentrated sulfuric acid and measured at 25 ° C. using an Ubbelohde viscometer.

(2) Measurement of the natural shrinkage rate After measuring the distance between marked lines (= L) marked on the film, the film was allowed to stand in a non-tensioned environment at 23 ° C. and 50% humidity for 24 hours. = ΔL) was measured, and the natural shrinkage rate (%) was calculated as ΔL / L × 100.

(3) Measurement of hot water shrinkage rate After measuring the natural shrinkage rate, the distance between marked lines (= L ') of the film was measured, and then left in 90 ° C hot water for 1 minute in a non-tensioned state. The amount of shrinkage (= ΔL ′) was measured and calculated as shrinkage (%) = ΔL ′ / L ′ × 100.

Example 1
(1) The inside of a 1 L separable flask equipped with a pre-synthetic agitator of polyamide, a reflux condenser, a nitrogen inlet pipe, and a raw material inlet is replaced with nitrogen gas, 500 ml of dehydrated toluene, dibutyl oxalate (formula (Having a repeating unit represented by (A)) 29.981 g (0.148 mol), 1,12-aminododecanoic acid (R _{1 of the} repeating unit represented by formula (B) is a straight chain having 11 carbon atoms Having a repeating unit which is an alkylene group) was charged in an amount of 63.835 g (0.296 mol). The separable flask was placed in an oil bath, the temperature of the oil bath was raised to 130 ° C., and the reaction was performed under reflux for 3 hours. After cooling the temperature of the oil bath to 50 ° C., dodecanediamine (having a repeating unit in which R _{2 of the} repeating unit represented by the formula (C) is a linear alkylene group having 12 carbon atoms) 29.7 g (0 .148 mol) in 50 ml of methanol was added and stirred for another 30 minutes. Note that all operations from preparation of raw materials to completion of the reaction were performed under a nitrogen stream of 50 ml / min. After completion of the reaction, it was vacuum dried at 50 ° C. for 24 hours.

(2) Preparation of polyamide and preparation of polyamide film ε-caprolactam in a 5 liter pressure vessel equipped with a stirrer, thermometer, torque meter, pressure gauge, nitrogen gas inlet, pressure outlet, pressure regulator and polymer outlet 1061.01 g (82 wt%) having a repeating unit in which R _{1 of the} repeating unit represented by the formula (B) is a linear alkylene group having 5 carbon atoms, hexamethylenediamine (represented by the formula (C) Having a repeating unit in which R ₂ is a linear alkylene group having 6 carbon atoms and adipic acid (wherein R _{3 in the} repeating unit represented by the formula (D) is a linear alkylene having 4 carbon atoms) 41.50 g of an equimolar salt 50% aqueous solution (having a repeating unit as a group) (equimolar salt of hexamethylenediamine and adipic acid: 16% by weight), pre-synthesis of (1) (2 wt%), were charged sodium hypophosphite 0.065 g, repeated several times with nitrogen pressure and pressure relief, was gradually heated pressure vessel after nitrogen substitution. Stirring was performed at a speed of 50 rpm. The temperature was raised from room temperature to 240 ° C. over 2 hours, polymerized at 240 ° C. for 2 hours, then released to a gauge pressure of 0 MPa, and then polymerized at 240 ° C. for 2.7 hours while flowing nitrogen gas at 260 ml / min. To obtain a polyamide. After completion of the polymerization, stirring was stopped, and a colorless and transparent polyamide in a molten state was drawn out from the polymer outlet in a string shape, cooled with water, and pelletized to obtain pellets. The pellet was stirred and washed in hot water for 6 hours to remove unreacted monomers, and then vacuum dried at 110 ° C. for 72 hours. Ηr of the obtained polyamide was 3.8.

  An unstretched film having a thickness of 100 μm was produced using about 2 g of the obtained polyamide under a condition of 260 ° C. using a press molding machine. Draw a marked line (50 mm interval) on a 90 mm long and 10 mm wide sample cut out from this unstretched film and attach it to a tensile tester (Orientec Tensilon RTA-10KN) at an ambient temperature of 80 ° C (stretching temperature). After preheating for about 1 minute, the film was stretched 2.7 times in the longitudinal direction of the film at a deformation speed of 150 mm / min at the same temperature. The stretched film was allowed to stand in an atmosphere of 23 ° C. and 50% RH for 24 hours, and then the natural shrinkage rate was measured to be 7.7%. Subsequently, the hot water shrinkage was measured and found to be 20.2%. The results are shown in Table 1.

(Comparative Example 1)
ε-caprolactam (having a repeating unit in which R _{1 of the} repeating unit represented by the formula (B) is a linear alkylene group having 5 carbon atoms) 1066.00 g (82 wt%), hexamethylenediamine (formula (C straight R ₃ is 4 carbon atoms of the repeating unit) R ₂ of the repeating unit represented by the represented by repeating with unit) adipic acid is a straight chain alkylene group of 6 carbon atoms (formula (D) 468.00 g of an equimolar salt 50% aqueous solution (having a repeating unit which is a chain alkylene group) (equimolar salt of hexamethylenediamine and adipic acid: 18% by weight) Except not using, it implemented by the method similar to an Example and obtained polyamide. The polyamide had a ηr of 4.0. An unstretched film and a stretched film were produced from this polyamide in the same manner as in the Examples, and the natural shrinkage was measured to find 9.6%. Subsequently, the hot water shrinkage was measured and found to be 18.9%. The results are shown in Table 1.

(Comparative Example 2)
ε-caprolactam (having a repeating unit in which R _{1 of the} repeating unit represented by the formula (B) is a linear alkylene group having 5 carbon atoms) 1040.00 g (80 wt%), 1,12-aminododecanoic acid In the same manner as in Comparative Example 1, 260.00 g (20% by weight) (having a repeating unit in which R _{1 of the} repeating unit represented by the formula (B) is a linear alkylene group having 11 carbon atoms) was charged. Carried out to obtain a polyamide. The polyamide had a ηr of 3.9. An unstretched film and a stretched film were produced from this polyamide in the same manner as in the Examples, and the natural shrinkage was measured and found to be 11.0%. Subsequently, the hot water shrinkage was measured and found to be 17.4%. The results are shown in Table 1.

* 1: ε-caprolactam has a repeating unit in which R _{1 of the} repeating unit represented by the formula (B) is a linear alkylene group having 5 carbon atoms. * 2: Hexamethylenediamine is represented by the formula (C). The repeating unit represented by R ₂ has a repeating unit that is a straight-chain alkylene group having 6 carbon atoms, and adipic acid is a straight chain in which R _{3 of the} repeating unit represented by the formula (D) is 4 carbon atoms. * 3: 1,12-aminododecanoic acid having a repeating unit that is a linear alkylene group has a repeating unit in which R _{1 of the} repeating unit represented by the formula (B) is a linear alkylene group having 11 carbon atoms

Claims (15)

A repeating unit represented by the following formula (A);
A repeating unit represented by the following formula (B);
[However, R ₁ represents a hydrocarbon group which may have a substituent. ]
A polyamide resin comprising a repeating unit represented by the following formula (C).
[However, R ₂ represents a hydrocarbon group which may have a substituent. R ₂ may be the same as or different from R _{1 in} formula (B). ] Furthermore, the polyamide resin of Claim 1 containing the repeating unit represented by a following formula (D).
[However, R ₃ represents a hydrocarbon group which may have a substituent. R ₃ is _{R 1,} it may be the same or different as _{R 2} of formula (C) of formula (B). ]   The polyamide resin according to claim 1 or 2, comprising at least two types of repeating units represented by the formula (B).   The polyamide resin according to any one of claims 1 to 3, comprising at least two types of repeating units represented by the formula (C). In all units of polyamide resin,
0.005 to 25% by weight of the repeating unit represented by the formula (A),
0.05 to 99.97% by weight of the repeating unit represented by the formula (B),
The polyamide resin according to any one of claims 1 to 4, comprising 0.02 to 49.99% by weight of the repeating unit represented by the formula (C). The polyamide resin according to any one of claims 1 to 5, comprising a repeating unit in which R _{1 of the} repeating unit represented by the formula (B) is an alkylene group having 1 to 11 carbon atoms. The polyamide resin according to any one of claims 1 to 6, comprising a repeating unit in which R _{3 of the} repeating unit represented by the formula (C) is an alkylene group having 1 to 12 carbon atoms. A repeating unit in which R _{1 of the} repeating unit represented by the formula (B) is an alkylene group having 5 carbon atoms;
A repeating unit in which R _{1 of the} repeating unit represented by the formula (B) is an alkylene group having 11 carbon atoms;
The polyamide resin according to any one of claims 1 to 7, comprising: A repeating unit in which R _{2 of the} repeating unit represented by the formula (C) is an alkylene group having 1 to 12 carbon atoms;
A repeating unit in which R _{3 of the} repeating unit represented by the formula (D) is an alkylene group having 1 to 10 carbon atoms;
The polyamide resin according to any one of claims 2 to 8, comprising: A repeating unit in which R _{2 of the} repeating unit represented by the formula (C) is a C 6 alkylene group;
A repeating unit in which R _{2 of the} repeating unit represented by the formula (C) is a C 12 alkylene group;
A repeating unit in which R _{3 of the} repeating unit represented by the formula (D) is a C 4 alkylene group;
The polyamide resin according to any one of claims 2 to 9, comprising:   The film containing the polyamide resin of any one of Claims 1-10.   The stretched film containing the polyamide resin of any one of Claims 1-10.   The biaxially stretched film containing the polyamide resin of any one of Claims 1-10.   A multilayer film comprising the film according to claim 11.   A packaging material comprising the film according to claim 11.