JP5639863B2 - MOLDING MATERIAL, MOLDED BODY, MANUFACTURING METHOD THEREOF, AND CASE FOR ELECTRIC AND ELECTRONIC DEVICE - Google Patents

Description

  The present invention relates to a molding material, a molded body, a manufacturing method thereof, and a casing for electric and electronic equipment.

Various materials are used for members constituting electric and electronic devices such as copiers and printers in consideration of characteristics and functions required for the members. For example, PC (Polycarbonate), ABS (Acrylonitrile-butadiene-styrene) resin, PC / ABS, etc. are generally used as a member (housing) that stores a drive machine for electrical and electronic equipment and protects the drive machine. In large amounts (Patent Document 1). These resins are produced by reacting compounds obtained from petroleum as a raw material.
By the way, fossil resources such as oil, coal, and natural gas are mainly composed of carbon that has been fixed in the ground for many years. When such fossil resources or products made from fossil resources are burned and carbon dioxide is released into the atmosphere, carbon that was originally not deep in the atmosphere but fixed deep in the ground Is rapidly released as carbon dioxide, and carbon dioxide in the atmosphere greatly increases, which causes global warming. Therefore, polymers such as ABS and PC made from petroleum, which is a fossil resource, have excellent characteristics as materials for electrical and electronic equipment, but are made from petroleum, which is a fossil resource. Therefore, it is desirable to reduce the amount used from the viewpoint of preventing global warming.
On the other hand, a plant-derived resin is originally produced by a photosynthesis reaction using carbon dioxide and water in the atmosphere as raw materials. Therefore, even if plant-derived resin is incinerated to generate carbon dioxide, the carbon dioxide is equivalent to carbon dioxide originally in the atmosphere, so the balance of carbon dioxide in the atmosphere is plus or minus zero After all, there is an idea that the total amount of CO _{2 in} the atmosphere is not increased. Based on this idea, plant-derived resins are referred to as so-called “carbon neutral” materials. The use of carbon-neutral materials in place of petroleum-derived resins is an urgent need to prevent global warming in recent years.
For this reason, in PC polymer, the method of reducing petroleum origin resources is proposed by using plant origin resources, such as starch, as some raw materials derived from petroleum (patent documents 2).
However, further improvements are required from the perspective of aiming for a more complete carbon neutral material.

As known cellulose derivatives, hydroxypropylmethylacetylcellulose is described in Patent Document 3 and Patent Document 4. Patent Document 3 and Patent Document 4 describe that this hydroxypropylmethylacetylcellulose is useful as an additive for reducing the vapor pressure of an organic solvent that easily volatilizes. In addition, the substitution degree of each substituent in hydroxypropylmethylacetylcellulose described in Patent Document 3 and Patent Document 4 is, for example, a molar substitution degree (MS) of hydroxypropyl group in a range of about 2 to 8, a substitution degree of methyl group Is in the range of about 0.1 to 1 and the degree of substitution of the acetyl group is in the range of about 0.8 to 2.5.
In addition, in order to improve the characteristics of such a cellulose resin, it is widely practiced to incorporate a low molecular weight, oligomer type or polymer type plasticizer. For example, a method of applying a plasticizer having a modified solubility parameter (SP value) has been studied. Patent Document 5 discloses a resin mainly composed of a cellulose ester resin and a plasticizer having a solubility parameter value of 9.0 or less. A composition is disclosed, and Patent Document 6 discloses a resin composition mainly composed of a cellulose ester resin and a plasticizer having a solubility parameter value of more than 9.0.

JP-A-56-55425 JP 2008-24919 A US Pat. No. 3,979,179 U.S. Pat. No. 3,940,384 JP 2008-291245 A JP 2008-291246 A

The inventors of the present invention focused on using cellulose as a carbon neutral resin. However, since cellulose generally does not have thermoplasticity, it is difficult to mold by heating or the like, and thus is not suitable for molding. Further, even if thermoplasticity can be imparted, there is a problem that strength such as impact resistance (for example, falling ball impact strength) and bending elastic modulus are greatly reduced.
For example, the cellulose derivatives described in Patent Documents 3 and 4 are water-soluble or swellable and insufficient in strength, which is not preferable as a molding material.
Patent Documents 5 and 6 disclose a resin composition mainly composed of a cellulose ester resin and a plasticizer having a specific solubility parameter (SP value) as described above. These resin compositions are optical films. The purpose of this is to manufacture. Patent Documents 5 and 6 are inventions aimed at providing a resin composition that forms a film with excellent transparency as is apparent from the Examples. In order to achieve high transparency, cellulose ester-based resins are used. It is necessary to use in combination with a plasticizer with high affinity and high polarity. On the other hand, as described later, the present invention dares to combine the cellulose derivative according to the present invention with a low affinity (low polarity) plasticizer to disperse the plasticizer unevenly and form particles. It is an invention intended. Therefore, Patent Documents 5 and 6 do not provide effects such as excellent falling ball impact strength as in the present invention. Patent Documents 5 and 6 do not describe a cellulose derivative having a specific structure according to the present invention having an ether structure and an ester structure.
From the viewpoint of ease of molding, the molding material preferably has low water absorption characteristics. A molding material having a low water absorption property is also required for a molding material containing a cellulose derivative.

  An object of the present invention is to provide a molding material and a molded article that are excellent in impact resistance such as falling ball impact strength, have low water absorption characteristics, and have a high flexural modulus. Another object of the present invention is to provide a method for producing the molded body and a housing for electrical and electronic equipment composed of the molded body.

Usually, when a cellulose resin is used for an optical film, a plasticizer having a low affinity with a cellulose derivative is not used because high transparency is required. In general, when a plasticizer having a low affinity is mixed with an ordinary cellulose derivative such as acetylcellulose, the cellulose derivative and the plasticizer are separated into individual phases, and generally the plasticizer phase is several tens of μm or more. Therefore, the resulting material has a poor mechanical strength. However, by using the cellulose derivative of the present invention and a plasticizer having an SP value in a specific range, it can be dispersed in small particles of several μm or less, and surprisingly by taking such a form. It has been found that the mechanical strength, particularly the falling ball impact strength, is dramatically increased.
The present inventors paid attention to the molecular structure of cellulose, and made cellulose a cellulose derivative having a specific structure having an ether structure and an ester structure, and the cellulose derivative having the specific structure and a solubility parameter (SP value) of less than 9 With a molding material containing a plasticizer within the range, this plasticizer forms a particle state with a range of sizes in the molding material, and as a result cannot be reached with conventional cellulosic resin and plasticizer combinations Molding material and molded body having low water absorption characteristics and high flexural modulus, method for producing the molded body, and electric and electronic equipment comprising the molded body The present inventors have found that a housing can be provided and have completed the present invention.

（式中、Ｒ _Ｃ１ は炭化水素基を表し、Ｒ _Ｃ２ は炭素数が２〜４のアルキレン基を表す。ｎは１以上の整数を表す。）
〔４〕
前記アルキレンオキシ基のモル置換度ＭＳが、０＜ＭＳ≦１．５である、〔３〕に記載の成形材料。
〔５〕
前記Ａ）炭素数１〜４のアルキル基：−Ｒ _Ａ の置換度ＤＳ _Ａ が、１．０＜ＤＳ _Ａ ≦２．５である、〔１〕〜〔４〕のいずれかに記載の成形材料。
〔６〕
前記Ｒ _Ａ がメチル基又はエチル基である、〔１〕〜〔５〕のいずれかに記載の成形材料。
〔７〕
前記Ｒ _Ｃ１ が、アルキル基又はアリール基である、〔２〕〜〔４〕のいずれかに記載の成形材料。
〔８〕
前記Ｒ _Ｂ 及びＲ _Ｃ１ が、それぞれ独立に、メチル基、エチル基、プロピル基、ブチル基、又は３−ヘプチル基である、〔２〕〜〔７〕のいずれかに記載の成形材料。
〔９〕
前記Ｒ _Ｂ が、炭素数３〜１０の分岐構造を有するアルキル基である、〔１〕〜〔７〕のいずれかに記載の成形材料。
〔１０〕
前記アルキレンオキシ基が下記式（１）又は（２）で表される基である、〔２〕〜〔４〕及び〔７〕のいずれかに記載の成形材料。

〔１１〕
前記セルロース誘導体が、カルボキシル基、スルホン酸基、及びこれらの塩を実質的に有さない、〔１〕〜〔１０〕のいずれかに記載の成形材料。
〔１２〕
前記セルロース誘導体が水に不溶である、〔１〕〜〔１１〕のいずれかに記載の成形材料。
〔１３〕
前記可塑剤が、エポキシ系可塑剤、ポリエステル系可塑剤及び多価カルボン酸系可塑剤からなる群より選ばれる少なくとも一つである、〔１〕〜〔１２〕のいずれかに記載の成形材料。
〔１４〕
前記可塑剤を成形材料の全固形分に対して１〜３０質量％含有する、〔１〕〜〔１３〕のいずれかに記載の成形材料。
〔１５〕
〔１〕〜〔１４〕のいずれかに記載の成形材料を成形して得られる成形体。
〔１６〕
〔１〕〜〔１４〕のいずれかに記載の成形材料を加熱し、成形する工程を含む、成形体の製造方法。
〔１７〕
〔１５〕に記載の成形体から構成される電気電子機器用筐体。
本発明は上記〔１〕〜〔１７〕に記載した事項に関するものであるが参考のためにその他の事項（たとえば下記＜１＞〜＜１７＞に記載した事項など）についても記載した。 That is, the said subject can be achieved by the following means.
[1]
The hydrogen atom of the hydroxyl group contained in cellulose
At least one group substituted in A) below, and
A cellulose derivative comprising at least one group substituted in B) below;
Containing a plasticizer having a solubility parameter (SP value) of less than 9;
The mass ratio of the cellulose derivative and the plasticizer (cellulose derivative / plasticizer) is 95/5 to 60/40,
The plasticizer forms particles in the cellulose derivative;
The molding material whose number average particle diameter of the said plasticizer which exists in the said cellulose derivative is 0.1 micrometer-10 micrometers.
A) an alkyl group having 1 to 4 carbon atoms: -R _A
B) Acyl group: —CO—R _B (R _B represents an alkyl group having 1 to 12 carbon atoms or an aryl group.)
[2]
The molding material according to claim 1, wherein the cellulose derivative further comprises at least one group in which a hydrogen atom of a hydroxyl group contained in cellulose is substituted by the following C).
C) a group containing an alkyleneoxy group: —R _C2 —O— and an acyl group: —CO—R _C1 (R _C1 represents a hydrocarbon group, and R _C2 represents an alkylene group having 2 to 4 carbon atoms. )
[3]
[Claim 2] The molding material according to [2], wherein the C) group containing an alkyleneoxy group and an acyl group is a group represented by the following general formula (3).

(Wherein R _C1 represents a hydrocarbon group, R _C2 represents an alkylene group having 2 to 4 carbon atoms, and n represents an integer of 1 or more.)
[4]
Molding material as described in [3] whose molar substitution degree MS of the said alkyleneoxy group is 0 <MS <= 1.5.
[5]
The molding material according to any one of [1] to [4], wherein the A) alkyl group having 1 to 4 carbon atoms: -R _{A has} a substitution degree DS _A of 1.0 <DS _A ≦ 2.5. .
[6]
The molding material according to any one of [1] to [5], wherein R _A is a methyl group or an ethyl group.
[7]
The molding material according to any one of [2] to [4], wherein R _C1 is an alkyl group or an aryl group.
[8]
The molding material according to any one of [2] to [7], wherein R _B and R _C1 are each independently a methyl group, an ethyl group, a propyl group, a butyl group, or a 3-heptyl group.
[9]
The molding material according to any one of [1] to [7], wherein R _B is an alkyl group having a branched structure having 3 to 10 carbon atoms.
[10]
The molding material according to any one of [2] to [4] and [7], wherein the alkyleneoxy group is a group represented by the following formula (1) or (2).

[11]
The molding material according to any one of [1] to [10], wherein the cellulose derivative does not substantially contain a carboxyl group, a sulfonic acid group, and a salt thereof.
[12]
The molding material according to any one of [1] to [11], wherein the cellulose derivative is insoluble in water.
[13]
The molding material according to any one of [1] to [12], wherein the plasticizer is at least one selected from the group consisting of an epoxy plasticizer, a polyester plasticizer, and a polycarboxylic acid plasticizer.
[14]
Molding material in any one of [1]-[13] which contains the said plasticizer 1-30 mass% with respect to the total solid of a molding material.
[15]
[1] A molded product obtained by molding the molding material according to any one of [14].
[16]
The manufacturing method of a molded object including the process of heating and molding the molding material in any one of [1]-[14].
[17]
[15] A casing for an electric and electronic device comprising the molded article according to [15].
The present invention relates to the items described in [1] to [17] above, but other items (for example, items described in <1> to <17> below) are also described for reference.

<1>
The hydrogen atom of the hydroxyl group contained in cellulose
A cellulose derivative comprising at least one group substituted in A) below and at least one group substituted in B) below;
A molding material containing a plasticizer having a solubility parameter (SP value) of less than 9.
A) Hydrocarbon group: -R _A
B) Acyl group: —CO—R _B (R _B represents a hydrocarbon group.)
<2>
The molding material according to <1>, wherein the cellulose derivative further contains at least one group in which a hydrogen atom of a hydroxyl group contained in cellulose is substituted by the following C).
C) a group containing an alkyleneoxy group: —R _C2 —O— and an acyl group: —CO—R _C1 (R _C1 represents a hydrocarbon group, and R _C2 represents an alkylene group having 2 to 4 carbon atoms. )
<3>
The molding material according to <2>, wherein the group C) containing an alkyleneoxy group and an acyl group is a group represented by the following general formula (3).

(Wherein R _C1 represents a hydrocarbon group, R _C2 represents an alkylene group having 2 to 4 carbon atoms, and n represents an integer of 1 or more.)
<4>
The molding material as described in any one of said <1>-<3> whose said _RA is a C1-C4 alkyl group.
<5>
The molding material as described in any one of said <1>-<4> whose said _RA is a methyl group or an ethyl group.
<6>
The molding material according to any one of <2> to <5>, wherein R _B and R _C1 are each independently an alkyl group or an aryl group.
<7>
The molding material according to any one of <2> to <6>, wherein R _B and R _C1 are each independently a methyl group, an ethyl group, a propyl group, a butyl group, or a 3-heptyl group. .
<8>
Wherein R _B is a hydrocarbon group having a branched structure having 3 to 10 carbon atoms, molding material according to any one of the above <1> to <6>.
<9>
The molding material as described in any one of said <2>-<8> whose said alkyleneoxy group is group represented by following formula (1) or (2).

<10>
Molding material as described in any one of said <1>-<9> in which the said cellulose derivative does not have a carboxyl group, a sulfonic acid group, and these salts substantially.
<11>
The molding material according to any one of <1> to <10>, wherein the cellulose derivative is insoluble in water.
<12>
The plasticizer according to any one of <1> to <11>, wherein the plasticizer is at least one selected from the group consisting of an epoxy plasticizer, a polyester plasticizer, and a polycarboxylic acid plasticizer. Molding material.
<13>
The molding material as described in any one of said <1>-<12> whose number average particle diameter of the said plasticizer which exists in the said cellulose derivative is 0.1 micrometer-10 micrometers.
<14>
Molding material as described in any one of said <1>-<13> which contains the said plasticizer 1-50 mass% with respect to the total solid of a molding material.
<15>
The molded object obtained by shape | molding the molding material as described in any one of said <1>-<14>.
<16>
The manufacturing method of a molded object including the process of heating and shape | molding the molding material as described in any one of said <1>-<14>.
<17>
A housing for electrical and electronic equipment comprising the molded article according to <15> above.

  Since the molding material of the present invention has excellent thermoplasticity, it can be molded by heat molding or the like. In addition, the molding material and the molded body of the present invention are excellent in terms of impact resistance such as falling ball impact strength, water absorption characteristics, and bending elastic modulus. -It can be suitably used as a building material. Furthermore, since the molding material of the present invention uses a cellulose derivative obtained from cellulose which is a plant-derived resin, it can be replaced with a conventional petroleum-derived resin as a material that can contribute to prevention of global warming.

In the present invention, the hydrogen atom of the hydroxyl group contained in cellulose is
A cellulose derivative (hereinafter also referred to as “cellulose derivative”) comprising at least one group substituted with A) below and at least one group substituted with B) below;
The present invention relates to a molding material containing a plasticizer having a solubility parameter (SP value) of less than 9.
A) Hydrocarbon group: -R _A
B) Acyl group: —CO—R _B (R _B represents a hydrocarbon group.)
Hereinafter, the present invention will be described in detail.

1. Cellulose derivative The cellulose derivative contained in the molding material of the present invention has a hydrogen atom of a hydroxyl group contained in cellulose.
A cellulose derivative comprising at least one group substituted with A) below and at least one group substituted with B) below.
A) Hydrocarbon group: -R _A
B) Acyl group: —CO—R _B (R _B represents a hydrocarbon group.)
That is, the cellulose derivative in the present invention is a cellulose ether ester, and at least a part of the hydrogen atoms of the hydroxyl group contained in cellulose {(C ₆ H ₁₀ O ₅ ) _n } is A) a hydrocarbon group: —R _A , B) Acyl group: substituted with —CO—R _B (R _B represents a hydrocarbon group).
More specifically, the cellulose derivative in the present invention has a repeating unit represented by the following general formula (A).

In the above general formula (A), R ² , R ³ and R ⁶ are each independently a hydrogen atom, A) a hydrocarbon group: —R _A , B) an acyl group: —CO—R _B (R _B is carbonized) Represents a hydrogen group) or other substituents. However, at least a part of R ² , R ³ , and R ⁶ represents A) a hydrocarbon group, and at least a part of R ² , R ³ , and R ⁶ represents B) an acyl group.

As described above, the cellulose derivative in the present invention has thermoplasticity due to etherification and esterification of at least part of the hydroxyl group of the β-glucose ring by A) a hydrocarbon group and B) an acyl group. It can be expressed and is suitable for molding.
Furthermore, since cellulose is a completely plant-derived component, it is carbon neutral and can greatly reduce the burden on the environment.

  The “cellulose” referred to in the present invention is a polymer compound in which a large number of glucoses are bonded by β-1,4-glycosidic bonds, and the carbon atoms at the 2nd, 3rd and 6th positions in the glucose ring of cellulose. Means that the hydroxyl group bonded to is unsubstituted. Further, “hydroxyl group contained in cellulose” refers to a hydroxyl group bonded to carbon atoms at the 2nd, 3rd and 6th positions in the glucose ring of cellulose.

The cellulose derivative only needs to contain the A) hydrocarbon group and B) acyl group in any part of the whole, and may be composed of the same repeating unit, or a plurality of types. It may consist of repeating units. The cellulose derivative does not need to contain all of the A) hydrocarbon group and B) acyl group in one repeating unit.
More specific embodiments include the following embodiments, for example.
(1) At least one of R ² , R ³ and R ⁶ is A) a repeating unit substituted with a hydrocarbon group, and at least one of R ² , R ³ and R ⁶ is substituted with B) an acyl group A cellulose derivative composed of repeating units.
(2) At least one of R ² , R ³ and R ⁶ of one repeating unit is substituted with A) a hydrocarbon group, and at least one of the other is substituted with B) an acyl group ( That is, a cellulose derivative composed of the same type of repeating units having the substituents A) and B) in one repeating unit.
(3) A cellulose derivative in which repeating units having different substitution positions and different types of substituents are bonded at random.
The cellulose derivative may contain an unsubstituted repeating unit (that is, a repeating unit in which R ² , R ³ and R ⁶ are all hydrogen atoms in the general formula (A)).
Moreover, the cellulose derivative may have other substituents other than a hydrogen atom, A) a hydrocarbon group, and B) an acyl group.

A) Hydrocarbon group: -R _A may be either an aliphatic group or an aromatic group.
When R _A is an aliphatic group, it may be linear, branched, or cyclic, and may have an unsaturated bond. Examples of the aliphatic group include an alkyl group, a cycloalkyl group, an alkenyl group, and an alkynyl group.
When R _A is an aromatic group, it may be either a single ring or a condensed ring. When _RA is an aromatic group, the preferable carbon number is 6-18, More preferably, it is 6-14, More preferably, it is 6-10. Examples of the aromatic group include a phenyl group, a naphthyl group, a phenanthryl group, and an anthryl group.
A) The hydrocarbon group is preferably an aliphatic group because the resulting molding material (hereinafter sometimes referred to as “cellulose resin composition” or “resin composition”) has excellent impact resistance. From the viewpoint of excellent molding processability such as melt flow rate and excellent bending elastic modulus of the molding material, an alkyl group is more preferable, and an alkyl group having 1 to 4 carbon atoms (lower alkyl group) is more preferable. Specific examples include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, pentyl group, hexyl group, heptyl group, 2-ethylhexyl group, tert-butyl group, isoheptyl group, and the like. A group or an ethyl group is particularly preferred.

B) an acyl group: In _{-CO-R B, R B} represents a hydrocarbon group. R _B is an aliphatic group, and may be any aromatic group.
If R _B is an aliphatic group, straight chain, branched, and may be any of circular, it may have an unsaturated bond. Examples of the aliphatic group include an alkyl group, a cycloalkyl group, an alkenyl group, and an alkynyl group.
If R _B is an aromatic group may be either monocyclic and condensed. Examples of the aromatic group include a phenyl group, a naphthyl group, a phenanthryl group, and an anthryl group.
R _B is preferably an alkyl group or an aryl group. R _B is, in view of flexural modulus, more preferably an alkyl group or an aryl group having 1 to 12 carbon atoms, more preferably an alkyl group having 1 to 12 carbon atoms, particularly preferably 1 to 4 carbon atoms Alkyl group (preferably methyl group, ethyl group, propyl group), and most preferably alkyl group having 1 or 2 carbon atoms (namely, methyl group or ethyl group).
Also, R _B, it is also preferably a hydrocarbon group having a branched structure having 3 to 10 carbon atoms, more preferably an alkyl group having a branched structure having 3 to 10 carbon atoms, having a carbon number of 7 to 9 More preferably, it is an alkyl group having a branched structure.
The R _B, specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a pentyl group, a hexyl group, a heptyl group, 3-heptyl group, tert- butyl group and isoheptyl group, Etc. Preferably, R _B is methyl, ethyl, propyl, butyl, or 3-heptyl group, more preferably a methyl group, an ethyl group, butyl group, or 3-heptyl group, most preferably methyl It is a group.

The cellulose derivative in the molding material of the present invention is a cellulose derivative in which the hydrogen atom of the hydroxyl group contained in cellulose contains at least one group substituted with A) and at least one group substituted with B). However, it is further preferable from the viewpoints of impact resistance and flexural modulus to contain at least one group in which the hydrogen atom of the hydroxyl group contained in cellulose is substituted by the following C).
C) a group containing an alkyleneoxy group: —R _C2 —O— and an acyl group: —CO—R _C1 (R _C1 represents a hydrocarbon group, and R _C2 represents an alkylene group having 2 to 4 carbon atoms. )

In the acyl group (—CO—R _C1 ) contained in C), R _C1 represents a hydrocarbon group. As the hydrocarbon group represented by R _{C1, the same} groups as those described above for R _B can be applied. The preferred range of R _C1 is the same as R _B.

In the alkyleneoxy group (—R _C2 —O—) contained in C), R _C2 represents an alkylene group having 2 to 4 carbon atoms. R _C2 preferably represents an alkylene group having 2 or 3 carbon atoms. R _C2 may be linear, branched or cyclic, but is preferably linear or branched, and more preferably branched.
Specific examples of the alkyleneoxy group (—R _C2 —O—) include the following structures.

Among them, a group represented by the following formula (1) or (2) in which —RC ₂ —O— is branched is preferable because the resulting molding material has excellent falling ball impact strength.

  The group C) may contain a plurality of alkyleneoxy groups or may contain only one. Preferably, the group of C) can be represented by the following general formula (3).

In the general formula (3), R _C1 represents a hydrocarbon group, and R _C2 represents an alkylene group having 2 to 4 carbon atoms. The preferred ranges of R _C1 and R _C2 are the same as those described above. n is an integer of 1 or more. The upper limit of n is not particularly limited, and varies depending on the amount of alkyleneoxy group introduced, but is about 10, for example. n is preferably 1 to 5, more preferably 1 to 3, and still more preferably 1. When a plurality of R _C2 are present, they may be the same or different, but are preferably the same.
In addition, the cellulose derivative in the present invention is a group of C) containing only one alkyleneoxy group (a group in which n is 1 in the general formula (3)) and C) containing two or more alkyleneoxy groups. And a group (a group in which n is 2 or more in the above general formula (3)).

Further, the bonding direction of the alkyleneoxy group to the cellulose derivative in the group C) is not particularly limited, but it is preferable that the alkylene group part (R _C2 ) of the alkyleneoxy group is bonded to the β-glucose ring structure side.

R _A in A), R B in _B ), R _C1 and R _C2 in C) may have a further substituent or may be unsubstituted, but are preferably unsubstituted.

_{R A} in the A), _{R B} in the B), in the case where the _{where R C1} and _{R C2} in the C) has a further substituent, examples of the further substituent include a halogen atom (e.g. fluorine atom, chlorine atom, bromine Atoms, iodine atoms), hydroxy groups, alkoxy groups (the alkyl group portion preferably has 1 to 5 carbon atoms), alkenyl groups, and the like. However, even when a substituent is included, the carbon number of R _C2 is 2 to 4, preferably 2 or 3. In _the case R A, _{R B,} and _{R C1} is other than alkyl group, an alkyl group (preferably having from 1 to 5 carbon atoms) may have as a substituent.

In particular, when R _B and R _C1 have a further substituent, it is preferable that they substantially have no carboxyl group, sulfonic acid group, and salts thereof. When the cellulose derivative is substantially free of carboxyl groups, sulfonic acid groups, and salts thereof, the molding material of the present invention can be made water-insoluble and the moldability can be further improved. In addition, when the cellulose derivative has a carboxyl group, a sulfonic acid group, and a salt thereof, it is known that the compound stability is deteriorated, and in particular, thermal decomposition may be promoted. It is preferable.
Note that “substantially free of carboxyl groups, sulfonic acid groups, and salts thereof” means only when the cellulose derivative in the present invention has no carboxyl groups, sulfonic acid groups, and salts thereof. In addition, the case where the cellulose derivative in the present invention has a trace amount of carboxyl groups, sulfonic acid groups, and salts thereof in a range insoluble in water is included. For example, a cellulose which is a raw material may contain a carboxyl group, and a cellulose derivative in which the substituents A) to C) are introduced using this may contain a carboxyl group. , A sulfonic acid group, and a cellulose derivative substantially free of salts thereof.
In this case, the preferred content of the carboxyl group, sulfonic acid group, and salts thereof is 1% by mass or less, more preferably 0.5% by mass or less, based on the cellulose derivative.

  Moreover, it is preferable that the cellulose derivative in this invention is insoluble in water. Here, “being insoluble in water” means that the solubility in 100 parts by mass of water at 25 ° C. is 5 parts by mass or less.

Specific examples of the cellulose derivative in the present invention include acetyl methyl cellulose, acetyl ethyl cellulose, acetyl propyl cellulose, acetyl butyl cellulose, acetyl pentyl cellulose, acetyl hexyl cellulose, acetyl cyclohexyl cellulose, acetyl phenyl cellulose, acetyl naphthyl cellulose, propionyl methyl cellulose, and propionyl ethyl cellulose. , Propionylpropylcellulose, propionylbutylcellulose, propionylpentylcellulose, propionylhexylcellulose, propionylcyclohexylcellulose, propionylphenylcellulose, propionylnaphthylcellulose, butyrylmethylcellulose, butyrylethylcellulose, butyrylpropylcellulose Butyrylbutylcellulose, butyrylpentylcellulose, butyrylhexylcellulose, butyrylcyclohexylcellulose, butyrylphenylcellulose, butyrylnaphthylcellulose, methylcellulose-2-ethylhexanoate, ethylcellulose-2-ethylhexanoate, propylcellulose 2-ethylhexanoate, butylcellulose-2-ethylhexanoate, pentylcellulose-2-ethylhexanoate, hexylcellulose-2-ethylhexanoate, cyclohexylcellulose-2-ethylhexanoate, phenylcellulose 2-ethylhexanoate, naphthylcellulose-2-ethylhexanoate, acetoxyethylmethylacetylcellulose, acetoxyethylethylacetylcellulose Acetoxyethylpropylacetylcellulose, acetoxyethylbutylacetylcellulose, acetoxyethylpentylacetylcellulose, acetoxyethylhexylacetylcellulose, acetoxyethylcyclohexylacetylcellulose, acetoxyethylphenylacetylcellulose, acetoxyethylnaphthylacetylcellulose, acetoxyethylmethylpropionylcellulose, acetoxy Ethylethylpropionylcellulose, acetoxyethylpropylpropionylcellulose, acetoxyethylbutylpropionylcellulose, acetoxyethylpentylpropionylcellulose, acetoxyethylhexylpropionylcellulose, acetoxyethylcyclohexylpropionylcellulose, acetoxyethyl Ruphenylpropionylcellulose, acetoxyethylnaphthylpropionylcellulose, acetoxyethylmethylcellulose-2-ethylhexanoate, acetoxyethylethylcellulose-2-ethylhexanoate, acetoxyethylpropylcellulose-2-ethylhexanoate, acetoxyethylbutylcellulose 2-ethylhexanoate, acetoxyethylpentylcellulose-2-ethylhexanoate, acetoxyethylhexylcellulose-2-ethylhexanoate, acetoxyethylcyclohexylcellulose-2-ethylhexanoate, acetoxyethylphenylcellulose-2-ethyl Hexanoate, acetoxyethyl naphthylcellulose-2-ethylhexanoate, propionyloxyethylmeth Ruacetylcellulose, propionyloxyethylethylacetylcellulose, propionyloxyethylpropylacetylcellulose, propionyloxyethylbutylacetylcellulose, propionyloxyethylpentylacetylcellulose, propionyloxyethylhexylacetylcellulose, propionyloxyethylcyclohexylacetylcellulose, propionyloxyethylphenylacetyl Cellulose, propionyloxyethyl naphthylacetyl cellulose, propionyloxyethylmethylpropionylcellulose, propionyloxyethylethylpropionylcellulose, propionyloxyethylpropylpropionylcellulose, propionyloxyethylbutylpropionylcellulose, propionyl Nyloxyethylpentylpropionylcellulose, propionyloxyethylhexylpropionylcellulose, propionyloxyethylcyclohexylpropionylcellulose, propionyloxyethylphenylpropionylcellulose, propionyloxyethylnaphthylpropionylcellulose, propionyloxyethylmethylcellulose-2-ethylhexanoate, propionyloxyethylethylcellulose 2-ethylhexanoate, propionyloxyethylpropylcellulose-2-ethylhexanoate, propionyloxyethylbutylcellulose-2-ethylhexanoate, propionyloxyethylpentylcellulose-2-ethylhexanoate, propionyloxyethylhexyl Cellulose 2-ethylhexanoate, propionyloxyethylcyclohexylcellulose-2-ethylhexanoate, propionyloxyethylphenylcellulose-2-ethylhexanoate, propionyloxyethylnaphthylcellulose-2-ethylhexanoate, acetoxypropylmethylacetyl Cellulose, acetoxypropylethylacetylcellulose, acetoxypropylpropylacetylcellulose, acetoxypropylbutylacetylcellulose, acetoxypropylpentylacetylcellulose, acetoxypropylhexylacetylcellulose, acetoxypropylcyclohexylacetylcellulose, acetoxypropylphenylacetylcellulose, acetoxypropylnaphthylacetylcellulose, Propioni Oxypropylmethylacetylcellulose, propionyloxypropylethylacetylcellulose, propionyloxypropylpropylacetylcellulose, propionyloxypropylbutylacetylcellulose, propionyloxypropylpentylacetylcellulose, propionyloxypropylhexylacetylcellulose, propionyloxypropylcyclohexylacetylcellulose, propionyloxy Examples thereof include propylphenylacetylcellulose, propionyloxypropylnaphthylacetylcellulose, valeroxypropylmethylvaleroylcellulose, valeroxybutylmethylvaleroylcellulose and the like.

  The molding material of the present invention may contain only one kind of the specific cellulose derivative, or may contain two or more kinds.

A) Hydrocarbon group: —R _A , B) Acyl group: —CO—R _B , and C) Alkyleneoxy group: —R _C2 —O— and acyl group: —CO—R _C1 in the cellulose derivative of the present invention And the number of substitution groups per β-glucose ring unit (substitution degree) are not particularly limited.

For example, A) Hydrocarbon group: Degree of substitution DS _{A of} -R _A (number of R _A with respect to hydroxyl groups at the 2nd, 3rd and 6th positions of the β-glucose ring in the repeating unit) is 1.0 <DS _A It is preferable that 1.0 <DS _A <2.5. Further, DS _A is preferably 1.1 or more.
B) Degree of substitution DS _{B of} acyl group (—CO—R _B ) (number of —CO—R _B with respect to hydroxyl groups at the 2nd, 3rd and 6th positions of the cellulose structure of the β-glucose ring in the repeating unit) 0.1 <DS _B is preferable, and 0.1 <DS _B <2.0 is more preferable.
C) Degree of substitution DS _C of a group containing an alkyleneoxy group: —R _C2 —O— and an acyl group: —CO—R _C1 (in the repeating unit, the 2nd, 3rd and 6th positions of the cellulose structure of the β-glucose ring) position of C to the hydroxyl group) alkyleneoxy _{group: -R} C2 -O- acyl group: the number of groups containing a _{-CO-R C1)} is preferably _{0 <DS C, 0 <DS} C <1 0.0 is more preferable. 0 <By a DS _C, it is possible to lower the melting initiation temperature of the cellulose derivative can be performed thermoforming easier.
By setting the degree of substitution within the above range, mechanical strength, moldability, and the like can be improved.

Further, the number of unsubstituted hydroxyl groups present in the cellulose derivative is not particularly limited. The degree of substitution DS _{H of} hydrogen atoms (ratio in which the hydroxyl groups at the 2nd, 3rd and 6th positions in the repeating unit are unsubstituted) can be in the range of 0 to 1.5, preferably 0 to 0.6. And it is sufficient. By the DS _H and 0.6 or less, or to improve the fluidity of the molding material, the foaming and the like due to water absorption of the molding material during acceleration and molding of the pyrolysis can or is suppressed.

In addition, the cellulose derivative in the present invention may have a substituent other than A) a hydrocarbon group, B) an acyl group, and C) a group containing an alkyleneoxy group and an acyl group. Examples of the substituent that may be included include a hydroxyethyl group, a hydroxypropyl group, a hydroxyethoxyethyl group, a hydroxypropoxypropyl group, a hydroxyethoxyethoxyethyl group, and a hydroxypropoxypropoxypropyl group. Therefore, the sum of the degree of substitution of all the substituents of the cellulose derivative is 3, but (DS _A + DS _B + DS _C + DS _H ) is 3 or less.

  The amount of alkyleneoxy group introduced in the group C) is expressed in terms of molar substitution (MS: number of moles of substituent introduced per glucose residue) (edited by Cellulose Society, Cellulose Dictionary P142). The molar substitution degree MS of the alkyleneoxy group is preferably 0 <MS, more preferably 0 <MS ≦ 1.5, and still more preferably 0 <MS <1.0. When MS is 1.5 or less (MS ≦ 1.5), heat resistance, moldability and the like can be improved, and a cellulose derivative suitable for a molding material can be obtained.

  The cellulose derivative in the molding material of the present invention is a cellulose derivative in which the hydrogen atom of the hydroxyl group contained in cellulose contains at least one group substituted with A) and at least one group substituted with B). However, when a hydrogen atom of a hydroxyl group contained in cellulose is substituted, from the viewpoint of moldability, it is substituted only by A) and B) or A), B), and C. ) Is preferred. That is, in the cellulose derivative in the present invention, it is preferable that the hydrogen atom of the hydroxyl group contained in the cellulose is not substituted with a group other than the above A), B), and C).

The molecular weight of the cellulose derivative in the present invention is preferably a number average molecular weight (Mn) in the range of 5 × 10 ^{3 to} 1000 × 10 ³ , more preferably in the range of 10 × 10 ^{3 to} 500 × 10 ³ , and 10 × 10 ³ to A range of 200 × 10 ³ is most preferred. The mass average molecular weight (Mw) is preferably in the range of 7 × 10 ^{3 to} 10000 × 10 ³ , more preferably in the range of 15 × 10 ^{3 to} 5000 × 10 ³ , and in the range of 100 × 10 ^{3 to} 3000 × 10 ³ . Is most preferred. By setting the average molecular weight within this range, it is possible to improve the moldability and mechanical strength of the molded body.
The molecular weight distribution (MWD) is preferably in the range of 1.1 to 10.0, and more preferably in the range of 1.5 to 8.0. By setting the molecular weight distribution within this range, moldability and the like can be improved.
In the present invention, the number average molecular weight (Mn), mass average molecular weight (Mw) and molecular weight distribution (MWD) can be measured using gel permeation chromatography (GPC). Specifically, N-methylpyrrolidone can be used as a solvent, a polystyrene gel can be used, and the molecular weight can be obtained using a conversion molecular weight calibration curve obtained in advance from a constituent curve of standard monodisperse polystyrene.

2. Method for Producing Cellulose Derivative The method for producing a cellulose derivative in the present invention is not particularly limited, and the cellulose derivative in the present invention can be produced by using cellulose as a raw material and etherifying and esterifying cellulose. The raw material for cellulose is not limited, and examples thereof include cotton, linter, and pulp.

A preferred embodiment of the method for producing a cellulose derivative having the above-mentioned A) hydrocarbon group: -R _A and B) acyl group: -CO-R _B (R _B represents a hydrocarbon group) includes cellulose ether, It includes a step of esterification by reacting acid chloride or acid anhydride in the presence.
As the cellulose ether, for example, one in which at least a part of the hydrogen atoms of the hydroxyl groups at the 2nd, 3rd and 6th positions of the β-glucose ring contained in cellulose is substituted with a hydrocarbon group can be used. Specific examples include methyl cellulose, ethyl cellulose, propyl cellulose, butyl cellulose, allyl cellulose, and benzyl cellulose.

A) hydrocarbon group: —R _A , B) acyl group: —CO—R _B (R _B represents a hydrocarbon group), and C) alkyleneoxy group: —R _C2 —O— and an acyl group: A preferred embodiment of a method for producing a cellulose derivative having a group containing —CO—R _C1 (R _C1 represents a hydrocarbon group, and R _C2 represents an alkylene group having 2 to 4 carbon atoms) is a hydrocarbon group. And hydroxyethyl cellulose ether having a hydroxyethyl group or hydroxypropyl cellulose ether having a hydroxypropyl group are reacted by an acid chloride or an acid anhydride to react with the esterification (acylation). is there.
Further, as another embodiment, for example, after etherification with cellulose ether such as methyl cellulose or ethyl cellulose with propylene oxide or the like, alkyl chloride such as methyl chloride or ethyl chloride / alkylene oxide having 3 carbon atoms or the like is allowed to act on cellulose. Furthermore, a method including a step of esterification by reacting an acid chloride or an acid anhydride is also included.
As a method for reacting acid chloride, for example, the method described in Cellulose 10; 283-296, 2003 can be used.
Specific examples of the cellulose ether having a hydrocarbon group and a hydroxyethyl group include hydroxyethyl methyl cellulose, hydroxyethyl ethyl cellulose, hydroxyethyl propyl cellulose, hydroxyethyl allyl cellulose, and hydroxyethyl benzyl cellulose. Preferred are hydroxyethyl methyl cellulose and hydroxyethyl ethyl cellulose.
Specific examples of the cellulose ether having a hydrocarbon group and a hydroxypropyl group include hydroxypropylmethylcellulose, hydroxypropylethylcellulose, hydroxypropylpropylcellulose, hydroxypropylallylcellulose, hydroxypropylbenzylcellulose, and the like. Preferred are hydroxypropylmethylcellulose and hydroxypropylethylcellulose.

  As the acid chloride, B) acyl group and carboxylic acid chloride corresponding to the acyl group contained in C) can be used. Examples of the carboxylic acid chloride include acetyl chloride, propionyl chloride, butyryl chloride, isobutyryl chloride, pentanoyl chloride, 2-methylbutanoyl chloride, 3-methylbutanoyl chloride, pivaloyl chloride, hexanoyl chloride, 2-methylpentanoyl chloride, 3-methylpentanoyl chloride, 4-methylpentanoyl chloride, 2,2-dimethylbutanoyl chloride, 2,3-dimethylbutanoyl chloride, 3,3-dimethylbutanoyl chloride, 2- Ethylbutanoyl chloride, heptanoyl chloride, 2-methylhexanoyl chloride, 3-methylhexanoyl chloride, 4-methylhexanoyl chloride, 5-methylhexanoyl chloride, 2,2-dimethylpentanoyl chloride, , 3-dimethylpentanoyl chloride, 3,3-dimethylpentanoyl chloride, 2-ethylpentanoyl chloride, cyclohexanoyl chloride, octanoyl chloride, 2-methylheptanoyl chloride, 3-methylheptanoyl chloride, 4-methyl Heptanoyl chloride, 5-methylheptanoyl chloride, 6-methylheptanoyl chloride, 2,2-dimethylhexanoyl chloride, 2,3-dimethylhexanoyl chloride, 3,3-dimethylhexanoyl chloride, 2-ethylhexanoyl Chloride, 2-propylpentanoyl chloride, nonanoyl chloride, 2-methyloctanoyl chloride, 3-methyloctanoyl chloride, 4-methyloctanoyl chloride, 5-methyloctanoyl chloride, 6-methyloctanoy Chloride, 2,2-dimethylheptanoyl chloride, 2,3-dimethylheptanoyl chloride, 3,3-dimethylheptanoyl chloride, 2-ethylheptanoyl chloride, 2-propylhexanoyl chloride, 2-butylpentanoyl chloride, Decanoyl chloride, 2-methylnonanoyl chloride, 3-methylnonanoyl chloride, 4-methylnonanoyl chloride, 5-methylnonanoyl chloride, 6-methylnonanoyl chloride, 7-methylnonanoyl chloride, 2,2- Examples include dimethyloctanoyl chloride, 2,3-dimethyloctanoyl chloride, 3,3-dimethyloctanoyl chloride, 2-ethyloctanoyl chloride, 2-propylheptanoyl chloride, 2-butylhexanoyl chloride and the like.

As the acid anhydride, for example, carboxylic acid anhydrides corresponding to the acyl group contained in the above B) acyl group and C) can be used. Examples of such carboxylic anhydrides include acetic anhydride, propionic anhydride, butyric anhydride, valeric anhydride, hexanoic anhydride, heptanoic anhydride, octanoic anhydride, 2-ethylhexanoic acid. An anhydride, nonanoic acid anhydride, etc. are mentioned.
As described above, since the cellulose derivative in the present invention preferably has no carboxylic acid as a substituent, for example, a dicarboxylic acid such as phthalic anhydride, maleic anhydride, or the like, and a compound that generates a carboxyl group by reacting with cellulose. It is preferable not to use.

  Other specific production conditions and the like can follow conventional methods. For example, a method described in “Encyclopedia of Cellulose” pages 131 to 164 (Asakura Shoten, 2000) can be referred to.

3. Plasticizer with a solubility parameter (SP value) of less than 9 The molding material of the present invention contains a plasticizer with a solubility parameter (SP value) of less than 9 (hereinafter also simply referred to as “plasticizer”). A plasticizer having a solubility parameter (SP value) of less than 9 means that the plasticizer is hydrophobic.
By containing a plasticizer having a solubility parameter (SP value) of less than 9 in the present invention, the molding material of the present invention obtained by blending with the cellulose derivative surprisingly exhibits high falling ball impact strength. The reason for this is not clear, but a plasticizer having a solubility parameter (SP value) of less than 9 has poor affinity with the cellulose derivative. Therefore, the plasticizer is not uniformly dispersed in the cellulose derivative. And particles are formed in the cellulose derivative. It is presumed that the particles formed by unevenly dispersing the plasticizer impart resistance to impact. Specifically, the presence of particles formed by uneven dispersion of the plasticizer in the molding material prevents the growth of microcracks caused by stress when force is applied, It is considered that the falling ball impact strength is increased by relaxing the stress by creating a crack. Furthermore, although a cellulose polymer is usually easy to absorb water, a molding material having low water absorption characteristics can be obtained by adding a plasticizer having a solubility parameter (SP value) of less than 9 (that is, a hydrophobic plasticizer) in the present invention. Can be obtained.

By blending such a plasticizer having a solubility parameter of less than 9 into the cellulose derivative, the plasticizer can be made into a particle state. The size of the particulate plasticizer present in the cellulose derivative is not particularly limited as long as the effect of the present invention is exhibited, but the number average particle diameter (diameter) is preferably 0.1 μm to 10 μm, more preferably 0.3 μm to It is 5 μm, particularly preferably 0.5 μm to 3 μm. When only a plasticizer having a solubility parameter of 9 or more is blended with the cellulose derivative of the present invention, such a particle state is not formed, or the number average particle diameter (diameter) of the particulate plasticizer present in the cellulose derivative. ) Becomes 0.05 μm or less, and the falling ball impact strength of the obtained molding material becomes low. In addition, since the number average particle diameter (diameter) of the particulate plasticizer present in the cellulose derivative is 0.1 μm or more, the stress that can be absorbed per particle increases, resulting in a falling ball impact strength. Lowering is preferable because it is suppressed, and it is preferable that the thickness is 10 μm or less because falling ball impact strength is suppressed due to a decrease in the interparticle distance.
The method for controlling the size of the plasticizer particles in such a molding material is not particularly limited, but as described above, a method for appropriately selecting the solubility parameter of the plasticizer, a method for changing the shearing force during kneading, Although a method of blending particles in which a plasticizer is previously encapsulated in a hard shell can be used, a method of selecting a solubility parameter of the plasticizer is preferable because it is easy and does not impair the properties of other molding materials.

The solubility parameter (SP value) of the plasticizer in the present invention is preferably less than 9, more preferably 7.5 or more and less than 9, and still more preferably 8 or more and less than 9. Here, the solubility parameter (SP value) can be determined by the Okitsu method. The Okitsu method is one of methods for calculating SP values well known in the art. 29, no. 6 (1993) 249-259. The Okitsu method has been improved to improve accuracy based on the small method, and there is no significant difference between the results obtained by both methods.
The plasticizer of the present invention is not particularly limited as long as the solubility parameter (SP value) is less than 9, but examples of the plasticizer of the present invention include alcohol plasticizers, amide plasticizers, ketone plasticizers, and epoxy resins. Plasticizers, isocyanate plasticizers, polyester plasticizers, glycerin plasticizers, polycarboxylic acid ester plasticizers, polyalkylene glycol plasticizers, aromatic carboxylic acid ester plasticizers, phosphate ester plasticizers, Examples include paraffinic process oils.

In the present invention, the plasticizer is at least one selected from the group consisting of an epoxy plasticizer, a polyester plasticizer, and a polycarboxylic acid plasticizer, because the resulting molding material has excellent falling ball impact strength. Is preferred.
As an epoxy plasticizer, epoxidized soybean oil, epoxidized linseed oil, epoxidized fatty acid octyl ester, epoxyhexahydrophthalic acid di-2-ethylhexyl, and the like can be used.
Specific examples of the polyester plasticizer include acid components such as adipic acid, sebacic acid, terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, rosin, propylene glycol, 1,3-butanediol, 1,4 -Polyesters composed of diol components such as butanediol, 1,6-hexanediol, ethylene glycol and diethylene glycol, and polyesters composed of hydroxycarboxylic acids such as polycaprolactone. These polyesters may be end-capped with a monofunctional carboxylic acid or monofunctional alcohol, or may be end-capped with an epoxy compound or the like.
Specific examples of the polyvalent carboxylic acid plasticizer include phthalic acid esters such as dioctyl phthalate and diheptyl phthalate, di (n-decyl) adipate, diisodecyl adipate, n-octyl-n-decyl adipate, Adipic acid esters such as methyl diglycol butyl diglycol adipate, benzyl methyl diglycol adipate, benzyl butyl diglycol adipate, diisononyl adipate, di-2-ethylhexyl adipate, azelaic acid di (n-hexyl), azelain Azelaic acid esters such as di-2-ethylhexyl acid, dibutyl sebacate, di-2-ethylhexyl sebacate, di-2-ethylhexyl dodecanedioate, tri-n-hexyl trimellitic acid, tri-2-trimellitic acid Ethylhexyl etc. It is below.
Preferably, epoxidized soybean oil, epoxidized linseed oil, epoxidized fatty acid octyl ester, epoxy-2-hydrohexyl hexahydrophthalate, adipic acid-ethylene glycol copolymer, adipic acid-butanediol copolymer, polycaprolactone Dioctyl phthalate, diisononyl adipate, di-2-ethylhexyl adipate, di-2-ethylhexyl sebacate, tri-2-ethylhexyl trimellitic acid, paraffinic process oil, more preferably epoxidized fatty acid octyl ester, epoxy hexa Di-2-ethylhexyl hydrophthalate, diisononyl adipate, di-2-ethylhexyl sebacate, adipic acid-ethylene glycol copolymer, tri-2-ethylhexyl trimellitic acid, most preferably Shin di-2-ethylhexyl adipate - ethylene glycol copolymer, trimellitic acid tri-2-ethylhexyl.
100-1000 are preferable, as for the molecular weight of the plasticizer whose solubility parameter (SP value) is less than 9, 200-900 are more preferable, 300-800 are still more preferable.
These plasticizers can be produced by a known method. Commercial products can also be used.

4). Molding material and molded body The content ratio of the cellulose derivative contained in the molding material of the present invention is not particularly limited as long as it is not 100% by mass. Preferably, the cellulose derivative is 50% by mass or more and 99% by mass or less, more preferably 60% by mass or more and 98% by mass or less, still more preferably 70% by mass or more and 95% by mass or less, and particularly preferably based on the total solid content of the molding material. 70 to 85% by mass is contained.
In the molding material of the present invention, the content of the plasticizer having the solubility parameter (SP value) of less than 9 is 1 to 50 mass with respect to the total solid content of the molding material of the present invention because of improvement in impact resistance. % Is preferable, 5 to 30% by mass is more preferable, and 10 to 25% by mass is still more preferable.
Moreover, as for the preferable content mass ratio of the said cellulose derivative and the said plasticizer, a cellulose derivative / plasticizer is 95 / 5-60 / 40, More preferably, it is 90 / 10-70 / 30.
Moreover, the molding material of this invention can contain another additive other than a cellulose derivative and a plasticizer as needed.

  In addition to the cellulose derivative, the molding material of the present invention may contain various additives such as an antioxidant, a filler (reinforcing material), and a flame retardant as necessary.

When the molding material of the present invention contains an antioxidant, its content is not limited, but is usually 30% by mass or less, preferably 0.01 to 10% by mass in the molding material. By setting it as this range, it is preferable from a viewpoint of coloring property improvement.
Examples of the antioxidant include hindered phenol antioxidants, phosphorus antioxidants, amine antioxidants, sulfur antioxidants, and hindered phenol antioxidants (for example, Ciba It is preferable to use “Irganox 1010” manufactured by Specialty Chemicals, “Sumilyzer GP” manufactured by Sumitomo Chemical Co., Ltd.).

The molding material of the present invention may contain a flame retardant. The flame retardant is not particularly limited as long as it is added for the purpose of imparting flame retardancy to the resin. By adding a flame retardant, a flame retardant effect such as a reduction or suppression of the burning rate of the molding material can be improved.
The flame retardant is not particularly limited, and a conventional flame retardant can be used. For example, brominated flame retardants, chlorine-based flame retardants, phosphorus-containing flame retardants, silicon-containing flame retardants, nitrogen compound-based flame retardants, inorganic flame retardants and the like can be mentioned. Among these, hydrogen halides are not generated by thermal decomposition during resin compounding or molding, and do not corrode processing machines or molds or deteriorate the working environment. Phosphorus-containing flame retardants and silicon-containing flame retardants are preferred because they are less likely to adversely affect the environment through the generation of harmful substances such as dioxins when they are diffused or decomposed.

  The phosphorus-containing flame retardant is not particularly limited, and a commonly used one can be used. Examples thereof include organic phosphorus compounds such as phosphate esters, condensed phosphate esters, and polyphosphates.

  Specific examples of phosphate esters include trimethyl phosphate, triethyl phosphate, tributyl phosphate, tri (2-ethylhexyl) phosphate, tributoxyethyl phosphate, triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, tris (isopropylphenyl) Phosphate, tris (phenylphenyl) phosphate, trinaphthyl phosphate, cresyl diphenyl phosphate, xylenyl diphenyl phosphate, diphenyl (2-ethylhexyl) phosphate, di (isopropylphenyl) phenyl phosphate, monoisodecyl phosphate, 2-acryloyloxyethyl Acid phosphate, 2-methacryloyloxyethyl acid phosphate, diphenyl Examples include 2-acryloyloxyethyl phosphate, diphenyl-2-methacryloyloxyethyl phosphate, melamine phosphate, dimelamine phosphate, melamine pyrophosphate, triphenylphosphine oxide, tricresylphosphine oxide, diphenyl methanephosphonate, diethyl phenylphosphonate be able to.

  Examples of phosphoric acid condensed esters include resorcinol polyphenyl phosphate, resorcinol poly (di-2,6-xylyl) phosphate, bisphenol A polycresyl phosphate, hydroquinone poly (2,6-xylyl) phosphate, and condensates thereof. Aromatic phosphoric acid condensed ester and the like.

  Moreover, the polyphosphate which consists of a salt of phosphoric acid, polyphosphoric acid, a periodic table group 1-14 group metal, ammonia, an aliphatic amine, and an aromatic amine can also be mentioned. As typical salts of polyphosphates, lithium salts, sodium salts, calcium salts, barium salts, iron (II) salts, iron (III) salts, aluminum salts and the like as metal salts, methylamine salts as aliphatic amine salts, Examples include ethylamine salts, diethylamine salts, triethylamine salts, ethylenediamine salts, piperazine salts, and examples of aromatic amine salts include pyridine salts and triazines.

In addition to the above, halogen-containing phosphate esters such as trischloroethyl phosphate, trisdichloropropyl phosphate, tris (β-chloropropyl) phosphate), and structures in which a phosphorus atom and a nitrogen atom are connected by a double bond Phosphazene compounds having phosphoric acid and phosphoric ester amides.
These phosphorus-containing flame retardants may be used singly or in combination of two or more.

  Examples of the silicon-containing flame retardant include an organic silicon compound having a two-dimensional or three-dimensional structure, polydimethylsiloxane, or a methyl group at a side chain or a terminal of polydimethylsiloxane, a hydrogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, Examples thereof include those substituted or modified with an aromatic hydrocarbon group, so-called silicone oils, or modified silicone oils.

Examples of the substituted or unsubstituted aliphatic hydrocarbon group and aromatic hydrocarbon group include an alkyl group, a cycloalkyl group, a phenyl group, a benzyl group, an amino group, an epoxy group, a polyether group, a carboxyl group, a mercapto group, Examples include a chloroalkyl group, an alkyl higher alcohol ester group, an alcohol group, an aralkyl group, a vinyl group, or a trifluoromethyl group.
These silicon-containing flame retardants may be used alone or in combination of two or more.

  Examples of the flame retardant other than the phosphorus-containing flame retardant or the silicon-containing flame retardant include, for example, magnesium hydroxide, aluminum hydroxide, antimony trioxide, antimony pentoxide, sodium antimonate, zinc hydroxystannate, zinc stannate, Metastannic acid, tin oxide, tin oxide salt, zinc sulfate, zinc oxide, ferrous oxide, ferric oxide, stannous oxide, stannic oxide, zinc borate, ammonium borate, ammonium octamolybdate, tungsten Inorganic flame retardants such as acid metal salts, complex oxides of tungsten and metalloid, ammonium sulfamate, ammonium bromide, zirconium compounds, guanidine compounds, fluorine compounds, graphite, and swellable graphite can be used. . These other flame retardants may be used alone or in combination of two or more.

  In the molding material of the present invention, the content of the flame retardant is not limited, but is preferably 30 parts by mass or less, more preferably 2 to 10 parts by mass with respect to 100 parts by mass of the cellulose derivative. By setting it as this range, impact resistance, brittleness, etc. can be improved, or generation | occurrence | production of pellet blocking can be suppressed.

The molding material of the present invention may contain a filler (reinforcing material). By containing the filler, the mechanical properties of the molded body formed of the molding material can be enhanced.
A well-known thing can be used as a filler. The shape of the filler may be any of fibrous, plate-like, granular, powdery and the like. Further, it may be inorganic or organic.
Specifically, as the inorganic filler, glass fiber, carbon fiber, graphite fiber, metal fiber, potassium titanate whisker, aluminum borate whisker, magnesium whisker, silicon whisker, wollastonite, sepiolite, slag fiber, zonolite, Elastadite, gypsum fiber, silica fiber, silica-alumina fiber, zirconia fiber, boron nitride fiber, silicon nitride fiber and boron fiber, and other inorganic fillers; glass flakes, non-swellable mica, carbon black, graphite, metal foil , Ceramic beads, talc, clay, mica, sericite, zeolite, bentonite, dolomite, kaolin, fine silicate, feldspar, potassium titanate, shirasu balloon, calcium carbonate, magnesium carbonate, barium sulfate, calcium oxide Beam, aluminum oxide, titanium oxide, magnesium oxide, aluminum silicate, silicon oxide, aluminum hydroxide, magnesium hydroxide, gypsum, novaculite, dawsonite, and a plate-like or granular inorganic fillers of clay or the like.

  Organic fillers include synthetic fibers such as polyester fiber, nylon fiber, acrylic fiber, regenerated cellulose fiber, and acetate fiber, and natural fibers such as kenaf, ramie, cotton, jute, hemp, sisal, Manila hemp, flax, linen, silk, and wool. Examples thereof include fibrous organic fillers obtained from microcrystalline cellulose, sugar cane, wood pulp, paper waste, waste paper and the like, and granular organic fillers such as organic pigments.

  When the molding material contains a filler, the content is not limited, but is usually 30 parts by mass or less, preferably 5 to 10 parts by mass with respect to 100 parts by mass of the cellulose derivative.

The molding material of the present invention may contain other components other than those described above for the purpose of further improving various properties such as moldability and flame retardancy within the range not impairing the object of the present invention. .
Examples of other components include the cellulose derivatives, polymers other than the plasticizers and flame retardants, stabilizers (ultraviolet absorbers, etc.), mold release agents (fatty acids, fatty acid metal salts, oxy fatty acids, fatty acid esters, aliphatic moieties. Saponified ester, paraffin, low molecular weight polyolefin, fatty acid amide, alkylene bis fatty acid amide, aliphatic ketone, fatty acid lower alcohol ester, fatty acid polyhydric alcohol ester, fatty acid polyglycol ester, modified silicone), antistatic agent, flame retardant aid, Examples include processing aids, anti-drip agents, antibacterial agents, and antifungal agents. Further, a coloring agent containing a dye or a pigment can be added.

As the polymer other than the cellulose derivative, the plasticizer, and the flame retardant, any of a thermoplastic polymer and a thermosetting polymer can be used, but a thermoplastic polymer is preferable from the viewpoint of moldability. Specific examples of polymers other than cellulose derivatives include low density polyethylene, linear low density polyethylene, high density polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-propylene-nonconjugated diene copolymer, ethylene-butene- 1 copolymer, polypropylene homopolymer, polypropylene copolymer (such as ethylene-propylene block copolymer), polyolefin such as polybutene-1 and poly-4-methylpentene-1, polybutylene terephthalate, polyethylene terephthalate and other aromatic polyesters, etc. Polyamide such as polyester, nylon 6, nylon 46, nylon 66, nylon 610, nylon 612, nylon 6T, nylon 12, etc., polystyrene, high impact polystyrene, polyacetate (Including homopolymers and copolymers), polyurethanes, aromatic and aliphatic polyketones, polyphenylene sulfide, polyetheretherketone, thermoplastic starch resins, polymethyl methacrylate and methacrylate-acrylate copolymers Acrylic resin, AS resin (acrylonitrile-styrene copolymer), ABS resin, AES resin (ethylene rubber reinforced AS resin), ACS resin (chlorinated polyethylene reinforced AS resin), ASA resin (acrylic rubber reinforced AS resin) ), Polyvinyl chloride, polyvinylidene chloride, vinyl ester resin, maleic anhydride-styrene copolymer, MS resin (methyl methacrylate-styrene copolymer), polycarbonate, polyarylate, polysulfone, polyethersulfone, phenoxy resin Thermoplastic polyimide such as polyphenylene ether, modified polyphenylene ether, polyetherimide, polytetrafluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-ethylene copolymer, tetrafluoroethylene-perfluoroalkyl vinyl ether Fluoropolymers such as polymers, polychlorotrifluoroethylene, polyvinylidene fluoride, tetrafluoroethylene-hexafluoropropylene-perfluoroalkyl vinyl ether copolymer, cellulose acetate, polyvinyl alcohol, unsaturated polyester, melamine resin, phenol resin, A urea resin, a polyimide, etc. can be mentioned.
In addition, various acrylic rubbers, ethylene-vinyl acetate copolymers, ethylene-acrylic acid copolymers and alkali metal salts thereof (so-called ionomers), ethylene-acrylic acid alkyl ester copolymers (for example, ethylene-ethyl acrylate copolymer) Copolymer, ethylene-butyl acrylate copolymer), diene rubber (for example, 1,4-polybutadiene, 1,2-polybutadiene, polyisoprene, polychloroprene), copolymer of diene and vinyl monomer (for example, Styrene-butadiene random copolymer, styrene-butadiene block copolymer, styrene-butadiene-styrene block copolymer, styrene-isoprene random copolymer, styrene-isoprene block copolymer, styrene-isoprene-styrene block copolymer Polymer, polybutadiene Styrene-grafted styrene, butadiene-acrylonitrile copolymer), polyisobutylene, copolymer of isobutylene and butadiene or isoprene, butyl rubber, natural rubber, thiocol rubber, polysulfide rubber, acrylic rubber, nitrile rubber, poly Examples include ether rubber, epichlorohydrin rubber, fluoro rubber, silicone rubber, and other thermoplastic elastomers such as polyurethane, polyester, and polyamide.

Furthermore, those having various degrees of crosslinking, those having various microstructures such as cis structure and trans structure, those having vinyl groups, those having various average particle diameters, core layers and the like A multi-layer structure polymer called a so-called core-shell rubber, which is composed of one or more shell layers to be covered and whose adjacent layers are composed of different types of polymers, can also be used, and further a core-shell rubber containing a silicone compound Can also be used.
These polymers may be used alone or in combination of two or more.

  When the molding material of this invention contains polymers other than a cellulose derivative, the said plasticizer, and a flame retardant, the content is 30 mass parts or less with respect to 100 mass parts of cellulose derivatives, and 2-10 mass parts is more. preferable.

The molded body of the present invention can be obtained by molding a molding material containing the cellulose derivative and the plasticizer. More specifically, the cellulose derivative and the plasticizer, or the manufacturing method including the step of heating the molding material containing various additives and the like as necessary to the cellulose derivative and the plasticizer, and molding by various molding methods. Obtained by.
The method for producing a molded body of the present invention includes a step of heating and molding the molding material.
Examples of the molding method include injection molding, extrusion molding, blow molding and the like.
The heating temperature is usually 160 to 300 ° C, preferably 180 to 260 ° C.

  The use of the molded article of the present invention is not particularly limited. For example, interior or exterior parts of electric and electronic equipment (home appliances, OA / media related equipment, optical equipment, communication equipment, etc.), automobiles, mechanical parts And materials for housing and construction. Among these, from the viewpoint of having excellent heat resistance and impact resistance and low environmental impact, for example, exterior parts (especially casings) for electrical and electronic equipment such as copiers, printers, personal computers, and televisions. ) Can be suitably used. That is, the housing for electrical and electronic equipment of the present invention is composed of the molded body of the present invention.

  EXAMPLES The present invention will be specifically described below with reference to examples and comparative examples, but the scope of the present invention is not limited to the examples shown below.

<Synthesis Example 1: Synthesis of acetoxypropylmethylacetylcellulose (C-1)>
Weigh 60 g of hydroxypropylmethylcellulose (trade name Metrolose 90SH-100; manufactured by Shin-Etsu Chemical Co., Ltd.) and 2100 mL of N, N-dimethylacetamide in a 5 L three-necked flask equipped with a mechanical stirrer, thermometer, condenser and dropping funnel, and stir at room temperature. did. After confirming that the reaction system became transparent and completely dissolved, 101 mL of acetyl chloride was slowly added dropwise to raise the temperature of the system to 80 ° C to 90 ° C. After stirring for 3 hours, the temperature of the reaction system was cooled to room temperature. When the reaction solution was added to 10 L of water with vigorous stirring, a white solid was precipitated. The white solid was filtered off by suction filtration and washed with a large amount of water three times. The obtained white solid was vacuum-dried at 100 ° C. for 6 hours to obtain the objective cellulose derivative (C-1) (acetoxypropylmethylacetylcellulose) as a white powder. The solubility of this cellulose derivative (C-1) in water at 25 ° C. was less than 0.1% by mass (insoluble).

<Synthesis Examples 2, 3, and 4: Synthesis of acetoxyethyl methyl acetyl cellulose (C-2), methyl acetyl cellulose (C-3), and ethyl acetyl cellulose (C-4)>
Hydroxypropyl methylcellulose (trade name Metrolose 90SH-100; manufactured by Shin-Etsu Chemical Co., Ltd.) in Synthesis Example 1 was replaced with hydroxyethyl methylcellulose (trade name Marporose ME-250T; manufactured by Matsumoto Yushi), methylcellulose (trade name Marporose M-4000: Matsumoto Yushi Co., Ltd.) Acetoxyethyl methyl acetyl cellulose (C-2), methyl acetyl cellulose (C-3), ethyl acetyl cellulose (C-3), and ethyl cellulose (trade name Etcel 300CP: manufactured by Dow Chemical). C-4) was obtained. All of these cellulose derivatives (C-2), (C-3), and (C-4) had a solubility in water at 25 ° C. of less than 0.1% by mass (insoluble).

<Synthesis Example 5: Synthesis of methylcellulose-2-ethylhexanoate (C-5)>
In a 3 L three-necked flask equipped with a mechanical stirrer, thermometer, condenser, and dropping funnel, 80 g of methylcellulose (manufactured by Wako Pure Chemical Industries, Ltd .: methyl substitution degree 1.8) and 1500 mL of pyridine were weighed and stirred at room temperature. 173 mL of 2-ethylhexanoyl chloride was dripped slowly under water cooling here, and also it stirred at 60 degreeC for 6 hours. After the reaction, the reaction solution was returned to room temperature and quenched by adding 200 mL of methanol under ice cooling. When the reaction solution was added to 12 L of water with vigorous stirring, a white solid was precipitated. The white solid was filtered off by suction filtration and washed 3 times with a large amount of methanol solvent. The obtained white solid was vacuum-dried at 100 ° C. for 6 hours to obtain methylcellulose-2-ethylhexanoate (C-5). The solubility of this cellulose derivative (C-5) in water at 25 ° C. was less than 0.1% by mass (insoluble).

<Synthesis Example 6: Synthesis of valeroxypropylmethyl valeroyl cellulose (C-6)>
Instead of methyl cellulose in Synthesis Example 5 (manufactured by Wako Pure Chemical Industries, Ltd .: methyl substitution degree 1.8), valeroyl was changed to hydroxypropyl methylcellulose (trade name Metroze 90SH-100; manufactured by Shin-Etsu Chemical Co., Ltd.) and 2-ethylhexanoyl chloride. Valeroxypropylmethyl valeroyl cellulose (C-6) was obtained in the same manner as in Synthesis Example 5 except that chloride was used. The solubility of this cellulose derivative (C-6) in water at 25 ° C. was less than 0.1% by mass (insoluble).

<Synthesis Example 7: Synthesis of valeroxybutyl methyl valeroyl cellulose (C-7)>
Valeroxybutylmethyl valeroyl cellulose (C-7) was synthesized in the same manner as in Synthesis Example 6 except that hydroxybutylmethylcellulose was used instead of hydroxypropylmethylcellulose (trade name Metroze 90SH-100; manufactured by Shin-Etsu Chemical Co., Ltd.) in Synthesis Example 6. Got. The solubility of this cellulose derivative (C-7) in water at 25 ° C. was less than 0.1% by mass (insoluble).

<Synthesis Example 8: Synthesis of benzoylpropylmethylacetylcellulose (C-8)>
Benzoylpropylmethylacetylcellulose (C-8) was obtained in the same manner except that the acetyl chloride in Synthesis Example 1 was changed to benzyl chloride (same mole number). The solubility of this cellulose derivative (C-8) in water at 25 ° C. was less than 0.1% by mass (insoluble).

In addition, the kind and substitution degree of the hydrocarbon group, the kind and molar substitution degree of the alkyleneoxy group, the kind of acyl group, and the acylation degree of the cellulose derivative obtained above are described in Cellulose Communication 6, 73-79 (1999). Were observed and determined by 1H-NMR. The degree of substitution of the hydrocarbon group is the number of moles of the hydrocarbon group substituted on the glucose ring unit, and takes a value of 0 or more and less than 3. The molar substitution degree of the alkyleneoxy group is the number of moles of the alkyleneoxy group substituted on the glucose ring unit, and takes a value of 0 or more. The degree of acylation indicates the degree of substitution with an acyl group by esterifying a hydroxyl group present in the glucose ring or ether substituent of cellulose, and is represented by 0 or more and 100 or less. In addition, since there is almost no difference between the reactivity of the acyl group with respect to the hydroxyl group of the glucose ring of cellulose and the reactivity of the acyl group with respect to the hydroxyl group derived from the alkyleneoxy group, C) of the group containing an alkyleneoxy group and an acyl group The molar substitution degree can be determined by multiplying the alkylene oxygen group molar substitution degree and the acylation degree.
Moreover, the colloid titration method is performed, and the substitution degree of the carboxyl group or sulfonic acid group in the cellulose derivatives (C-1) to (C-8) is less than 0.02 (that is, the content of the carboxyl group or sulfonic acid group is It was confirmed that it was less than 0.5% by mass with respect to the cellulose derivative.

<Measurement of molecular weight of cellulose derivative>
About the obtained cellulose derivative, the number average molecular weight (Mn) and the mass average molecular weight (Mw) were measured. These measuring methods are as follows.
[Molecular weight and molecular weight distribution]
For the measurement of the number average molecular weight (Mn) and the mass average molecular weight (Mw), gel permeation chromatography (GPC) was used. Specifically, N-methylpyrrolidone was used as a solvent, a polystyrene gel was used, and the molecular weight was determined using a conversion molecular weight calibration curve obtained in advance from a constituent curve of standard monodisperse polystyrene. As the GPC apparatus, HLC-8220 GPC (manufactured by Tosoh Corporation) was used.

  The number average molecular weight (Mn), the mass average molecular weight (Mw) and the degree of substitution are shown together in Table 1.

[Production of molded body]
Cellulose derivatives (C-1 to C-8, H-1) and plasticizers (P-1 to P-9) were added in parts by mass shown in Table 2 below, and an antioxidant (Ciba Specialty Chemicals) was added. After adding 0.5 parts by mass of “Irganox 1010” manufactured by the company, a mixture for molding material was prepared by mixing with a Henschel mixer. This mixture was supplied to a twin-screw kneading extruder (manufactured by Technobel Co., Ltd., Ultrano) set at a barrel temperature of 210 ° C. to produce pellets. Subsequently, the obtained pellets were supplied to a small injection molding machine (FANUC ROBOSHOT S-2000i, automatic injection molding machine), and a multipurpose test piece (bending test piece, length 80 mm × width 10 mm × thickness 4 mm) HDT test piece) and a plate-like test piece having a width of 5 cm, a length of 8 cm and a thickness of 2 mm were formed.

[Plasticizer]
Additive P-1: Di-2-ethylhexyl sebacate (SP value: 8.9)
Additive P-2: Adipic acid-ethylene glycol copolymer (weight average molecular weight 550, SP value: 8.9, "Adeka Sizer RS-700" manufactured by Adeka Corporation)
Additive P-3: Tri-2-ethylhexyl trimellitic acid (SP value: 8.7)
Additive P-4: Diisononyl adipate (SP value: 8.5)
Additive P-5: Epoxidized fatty acid octyl ester (SP value: 8.5)
Additive P-6: Epoxyhexahydrophthalic acid di-2-ethylhexyl (SP value: 8.3)
Additive P-7: Epoxidized soybean oil (SP value: 8.0, “Sanso Sizer E-2000H” manufactured by Shin Nippon Chemical Co., Ltd.)
Additive P-8: Paraffinic process oil (SP value: 7.9, “Diana Process Oil NR” manufactured by Idemitsu Kosan Co., Ltd.)
Additive P-9: dialkylene glycol dibenzoate (SP value: 9.9)

[Evaluation]
The following items were evaluated using the obtained multipurpose test pieces and plate-like test pieces. The evaluation results are shown in Table 2.
(Size of plasticizer particles in molding material (number average particle diameter))
The obtained multipurpose test piece is put into liquid nitrogen, completely cooled and then broken, and the central part of the test piece is observed with a scanning electron microscope (SEM) to determine the size of the plasticizer particles in the molding material. Was calculated as an average value (number average) of about 1,000 particles by image analysis.
(Falling ball impact test)
According to JIS K7211-1, both ends of the plate-shaped test piece (1 cm each out of the length of 8 cm) are fixed, and a 500 g steel ball is placed from the predetermined height to the center of the test piece using a cylindrical guide. It was dropped and it was observed whether or not a crack penetrated the test piece. A test was performed on a plurality of test pieces, and the height when the probability that a crack penetrates the test piece was 50% was obtained. From the results, 50% fracture energy (unit J) was determined and used as the falling ball impact strength. The test was conducted at 23 ° C.
(Water absorption characteristics (water content when immersed in water))
In accordance with JIS K 7209, the multi-purpose test piece was dried at 50 ° C. for 24 hours, then subjected to mass measurement, immersed in a constant temperature water bath at 23 ° C. for 24 hours, taken out of the test piece, and attached to the surface. Removed moisture and immediately measured the mass. The moisture content (%) was determined by {(mass after immersion / mass before immersion-1) × 100}. The measurement is an average of three measurements. When the water content is 3.0% or less, it means that it can be practically used as a molding material.
(Flexural modulus)
In accordance with ISO 178, a multi-purpose test piece molded by injection molding is prepared at 23 ° C. ± 2 ° C. and 50% ± 5% RH for 48 hours or more, and then between fulcrums by Instron (Toyo Seiki, Strograph V50) Measurement was performed at a distance of 64 mm and a test speed of 2 mm / min. The measurement is an average of three measurements. The results are shown in Table 2. In addition, that a bending elastic modulus is 1 GPa or more means that a molding material can be used practically satisfactorily.

The molding materials of Examples 1 to 17 all had a plasticizer-dispersed particle size in the material of 0.3 to 5.0 μm, high falling ball impact strength, low water absorption characteristics, and high flexural modulus.
The molding material of Comparative Example 1 containing no plasticizer in the present invention had a low falling ball impact strength and a high water absorption property. Further, in the molding material of Comparative Example 2 using a cellulose resin other than the present invention, the plasticizer was uniformly dispersed and particles were not formed, and the falling ball impact strength was low. Further, in the molding material of Reference Example 3 using a plasticizer having an SP value of 9.0 or more, the plasticizer was uniformly dispersed and particles were not formed, and the falling ball impact strength was low.

Claims (17)

The hydrogen atom of the hydroxyl group contained in cellulose
A cellulose derivative comprising at least one group substituted in A) below and at least one group substituted in B) below;
Containing a plasticizer having a solubility parameter (SP value) of less than 9 ;
The mass ratio of the cellulose derivative and the plasticizer (cellulose derivative / plasticizer) is 95/5 to 60/40,
The plasticizer forms particles in the cellulose derivative;
The molding material whose number average particle diameter of the said plasticizer which exists in the said cellulose derivative is 0.1 micrometer-10 micrometers .
A) an alkyl group having 1 to 4 carbon atoms : -R _A
B) Acyl group: —CO—R _B (R _B represents an alkyl group having 1 to 12 carbon atoms or an aryl group .) The molding material according to claim 1, wherein the cellulose derivative further comprises at least one group in which a hydrogen atom of a hydroxyl group contained in cellulose is substituted by the following C).
C) a group containing an alkyleneoxy group: —R _C2 —O— and an acyl group: —CO—R _C1 (R _C1 represents a hydrocarbon group, and R _C2 represents an alkylene group having 2 to 4 carbon atoms. ) The molding material according to claim 2, wherein the C) group containing an alkyleneoxy group and an acyl group is a group represented by the following general formula (3).

(Wherein R _C1 represents a hydrocarbon group, R _C2 represents an alkylene group having 2 to 4 carbon atoms, and n represents an integer of 1 or more.)   The molding material of Claim 3 whose molar substitution degree MS of the said alkyleneoxy group is 0 <MS <= 1.5.   A) the alkyl group having 1 to 4 carbon atoms: -R _A Degree of substitution DS _A However, 1.0 <DS _A The molding material according to claim 1, wherein ≦ 2.5. Wherein R _A is a methyl group or an ethyl group, molding material according to any one of claims 1-5. The molding material according to any one of claims 2 to 4 , wherein R _C1 is an alkyl group or an aryl group. Wherein R _B and R _C1 are each independently a methyl group, an ethyl group, a propyl group, a butyl group, or 3-heptyl group, molding material according to any one of claims 2-7. Wherein R _B is an alkyl group having a branched structure having 3 to 10 carbon atoms, molding material according to any one of claims 1-7. The molding material as described in any one of Claims 2-4 and 7 whose said alkyleneoxy group is group represented by following formula (1) or (2).

The molding material as described in any one of Claims 1-10 in which the said cellulose derivative does not have a carboxyl group, a sulfonic acid group, and these salts substantially. The molding material according to any one of claims 1 to 11 , wherein the cellulose derivative is insoluble in water. The molding material according to any one of claims 1 to 12 , wherein the plasticizer is at least one selected from the group consisting of an epoxy plasticizer, a polyester plasticizer, and a polycarboxylic acid plasticizer . Wherein for 1 containing 30 wt% of a plasticizer with respect to the total solid content of the molding material, the molding material according to any one of claims 1 to 13.   The molded object obtained by shape | molding the molding material as described in any one of Claims 1-14.   The manufacturing method of a molded object including the process of heating and shape | molding the molding material as described in any one of Claims 1-14.   A housing for electrical and electronic equipment comprising the molded body according to claim 15.