JP5458846B2 - Electrophotographic member containing a novel polyamide resin - Google Patents

Description

  The present invention relates to an electrophotographic member containing a novel polyamide resin composition. Specifically, it is an electrophotographic member excellent in surface smoothness and dimensional stability, excellent in chemical resistance and hydrolysis resistance as compared with an electrophotographic member such as nylon 6, and has 1, as a diamine component. It is dispersed in the polyamide resin, which has a wider moldable temperature range than materials using 9-nonanediamine alone, has excellent melt moldability, and can produce a tough electrophotographic member that can be made high in molecular weight. The present invention relates to a member for electrophotography comprising a layered silicate and a conductivity imparting agent and blended with a conductivity imparting material.

  Crystalline polyamides represented by nylon 6, nylon 66 and the like are widely used as materials for clothing, industrial materials, or general-purpose engineering plastics because of their excellent characteristics and ease of melt molding. On the other hand, problems such as changes in physical properties due to water absorption, acid, high-temperature alcohol, deterioration in hot water, etc. have been pointed out, and there is a need for a polyamide resin having lower water absorption and excellent chemical resistance and the polyamide resin. It is growing.

  Crystalline polyamides are preferably crystallized sufficiently in order to exhibit their characteristics. However, crystalline polyamides such as nylon 6 and nylon 66 generally have a low crystallization rate, and depending on molding conditions. There is a problem that the crystallization of the polyamide during molding is insufficient, the crystallization of the polyamide occurs after molding, and the dimensional stability is poor. Therefore, there is a demand for a polyamide resin having a high crystallization speed and excellent dimensional stability even when molded under various molding conditions and a molded body produced using the polyamide resin.

  On the other hand, a polyamide resin using oxalic acid as a dicarboxylic acid component is called a polyoxamide resin, and is known to have a higher melting point and lower water absorption than other polyamide resins having the same amino group concentration (Patent Document 1). In addition, it is expected to be used in fields where conventional polyamides are difficult to use due to changes in physical properties due to water absorption.

  So far, polyoxamide resins using various aliphatic linear diamines as diamine components have been proposed. However, for example, a polyoxamide resin using 1,6-hexanediamine as a diamine component has a melting point (about 320 ° C.) higher than the thermal decomposition temperature (1% weight loss temperature in nitrogen; about 310 ° C.) (non-patent document). 1) Melt polymerization and melt molding were difficult and could not withstand practical use.

For a polyoxamide resin whose diamine component is 1,9-nonanediamine (hereinafter abbreviated as PA92), L. Franco et al. Discloses a production method and its crystal structure when diethyl oxalate is used as the oxalic acid source ( Non-patent document 2). The PA 92 obtained here is a polymer having an intrinsic viscosity of 0.97 dL / g and a melting point of 246 ° C., but only a low molecular weight substance that cannot form a tough molded article is obtained. In addition, JP-A-5-506466 discloses that PA92 having an intrinsic viscosity of 0.99 dL / g and a melting point of 248 ° C. was produced when dibutyl oxalate was used as the dicarboxylic acid ester ( Patent Document 2). In this case as well, there is a problem that only a low molecular weight body that cannot be formed into a tough molded body is obtained.
In the prior literature, there was no specific disclosure of a polyoxamide resin using two kinds of diamines of 1,9-nonanediamine and 2-methyl-1,8-octanediamine as a diamine component in a specific ratio. Further, in the use of electrophotographic members, there is a demand for conductivity for the purpose of preventing charging. Furthermore, there is a demand for a tough molded body having a high surface hardness.

  The present invention has been made based on the above circumstances, and the present invention is superior in surface smoothness and dimensional stability, and excellent in chemical resistance and hydrolysis resistance as compared with a molding material such as nylon 6. It is a molding material, and has a wider moldable temperature range and excellent melt moldability than a material using 1,9-nonanediamine alone as a diamine component, and can produce a tough molded body capable of increasing the molecular weight. It is an object of the present invention to provide an electrophotographic member containing a layered silicate dispersed in the polyamide resin and blended with a conductivity imparting material.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that from oxalic acid diester as a oxalic acid source, 1,9-nonanediamine and 2-methyl-1,8-octanediamine as diamine components. It has been found that the above-mentioned problems can be solved by using the resulting polyamide resin as a molding material, and the present invention has been completed.

Specifically, the present invention relates to the following aspects.
[Aspect 1]
An electrophotographic member comprising a polyamide resin and a layered silicate dispersed in the polyamide resin, and blended with a conductivity imparting material, wherein the dicarboxylic acid component of the polyamide resin is composed of oxalic acid, and the diamine component is It consists of 1,9-nonanediamine and 2-methyl-1,8-octanediamine, and the molar ratio of 1,9-nonanediamine to 2-methyl-1,8-octanediamine is 1:99 to 99: 1. An electrophotographic member containing a polyamide resin.

[Aspect 2]
Aspect 1 in which the relative viscosity (ηr) measured at 25 ° C. using a polyamide resin solution having a concentration of 1.0 g / dl using 96% sulfuric acid as a solvent is 1.8 to 6.0. The member for electrophotography described in 1.
[Aspect 3]
1% weight loss temperature in thermogravimetric analysis of the polyamide resin measured at a temperature rising rate of 10 ° C./min in a nitrogen atmosphere, and differential scanning calorimetry measured at a temperature rising rate of 10 ° C./min in a nitrogen atmosphere. The electrophotographic member according to the aspect 1 or 2, wherein the temperature difference from the melting point measured by the step is 50 ° C or higher.

[Aspect 4]
The member for electrophotography according to any one of aspects 1 to 3, wherein the molar ratio of 1,9-nonanediamine to 2-methyl-1,8-octanediamine is 5:95 to 95: 5.

[Aspect 5]
The member for electrophotography according to any one of claims 1 to 4, wherein a content of the layered silicate is 0.05 to 10 parts by mass with respect to 100 parts by mass of the polyamide resin.

[Aspect 6]
The member for electrophotography according to any one of claims 1 to 5, wherein the layered silicate is an aluminum silicate phyllosilicate or a magnesium silicate phyllosilicate.

  The electrophotographic member of the present invention is a molding material that is excellent in surface smoothness and dimensional stability, excellent in chemical resistance and hydrolysis resistance as compared with a molding material such as nylon 6, and as a diamine component. A tough electrophotographic member having a wider moldable temperature range and excellent melt moldability than that of a material using 1,9-nonanediamine alone can be produced.

Hereinafter, the present invention will be described in detail.
[Polyamide resin]
In the polyamide resin used in the present invention, the dicarboxylic acid component is composed of oxalic acid, the diamine component is composed of 1,9-nonanediamine and 2-methyl-1,8-octanediamine, and 1,9-nonanediamine and 2-methyl- The molar ratio with 1,8-octanediamine is 1:99 to 99: 1.

  As the oxalic acid source as the dicarboxylic acid source of the polyamide resin used in the present invention, oxalic acid diester is used, and there is no particular limitation as long as it has reactivity with an amino group. Dimethyl oxalate, diethyl oxalate, oxalic acid Di-n- (or i-) propyl, oxalic acid diesters of aliphatic monohydric alcohols such as di-n- (or i-, or t-) butyl oxalate, oxalic acid diesters of alicyclic alcohols such as dicyclohexyl oxalate, diphenyl oxalate, etc. And oxalic acid diesters of aromatic alcohols.

  Among the above oxalic acid diesters, oxalic acid diesters of aliphatic monohydric alcohols having more than 3 carbon atoms, oxalic acid diesters of alicyclic alcohols, and oxalic acid diesters of aromatic alcohols are preferred, and among them, dibutyl oxalate and diphenyl oxalate are particularly preferred.

  In the polyamide resin used in the present invention, oxalic acid is used as the dicarboxylic acid source, but other dicarboxylic acid components can be blended within a range that does not impair the effects of the present invention. Examples of dicarboxylic acid components other than succinic acid include malonic acid, dimethylmalonic acid, succinic acid, glutaric acid, adipic acid, 2-methyladipic acid, trimethyladipic acid, pimelic acid, 2,2-dimethylglutaric acid, 3, Aliphatic dicarboxylic acids such as 3-diethylsuccinic acid, azelaic acid, sebacic acid and suberic acid, alicyclic dicarboxylic acids such as 1,3-cyclopentanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid, and terephthalic acid , Isophthalic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,4-phenylenedioxydiacetic acid, 1,3-phenylenedioxydiacetic acid, dibenzoic acid Acid, 4,4′-oxydibenzoic acid, diphenylmethane-4,4′-dicarboxylic acid, diphenylsulfuric acid Down-4,4'-dicarboxylic acid, 4,4'-biphenyl dicarboxylic acid aromatic dicarboxylic acids such as such alone or may be added any mixtures thereof during the polycondensation reaction. Furthermore, polycarboxylic acids such as trimellitic acid, trimesic acid, and pyromellitic acid can be used within a range where melt molding is possible.

  The blending amount of the other dicarboxylic acid is not particularly limited as long as the effects of the present invention are not impaired. In general, it is preferably 5 mol% or less with respect to the total amount of the dicarboxylic acid.

  As the diamine component, 1,9-nonanediamine and 2-methyl-1,8-octanediamine are used. The molar ratio of the 1,9-nonanediamine component to the 2-methyl-1,8-octanediamine component is 1:99 to 99: 1, preferably 5:95 to 95: 5. By copolymerizing a specific amount of 1,9-nonanediamine and 2-methyl-1,8-octanediamine, a polyamide having a high molecular weight and a high melt viscosity can be obtained as compared with a conventional polyamide.

Furthermore, the molar ratio of 1,9-nonanediamine to 2-methyl-1,8-octanediamine is preferably, for example, 5:95 to 40:60 or 60:40 to 95: 5, and 5: It is particularly preferred that it is 95-30: 70 or 70: 30-90: 10.
When the molar ratio is 5:95 to 40:60, particularly 5:95 to 30:70, the crystallinity is excellent, so that low water absorption and mechanical properties are excellent, and liquid and / or vapor (for example, , Alcohol) has low permeability, and more water absorption than the case where the molar content of 1,9-nonanediamine is higher than the molar content of 2-methyl-1,8-octanediamine. There is an advantage that it is low. On the other hand, when the molar ratio is 60:40 to 95: 5, particularly 70:30 to 90:10, there is an advantage that low water absorption and mechanical properties are more excellent and excellent transparency is imparted. .

  Further, in the polyamide resin used in the present invention, 1,9-nonanediamine and 2-methyl-1,8-octanediamine are used as diamine components, but other diamine components are used within a range not impairing the effects of the present invention. Can be blended. Examples of diamine components other than 1,9-nonanediamine and 2-methyl-1,8-octanediamine include ethylenediamine, propylenediamine, 1,4-butanediamine, 1,6-hexanediamine, and 1,8-octanediamine. 1,10-decanediamine, 1,12-dodecanediamine, 3-methyl-1,5-pentanediamine, 2,2,4-trimethyl-1,6-hexanediamine, 2,4,4-trimethyl-1 , 6-hexanediamine, aliphatic diamines such as 5-methyl-1,9-nonanediamine, cyclohexanediamine, methylcyclohexanediamine, and cycloaliphatic diamines such as isophoronediamine, p-phenylenediamine, m-phenylenediamine, p -Xylenediamine, m-xylenediamine, 4,4'-diamy Diphenylmethane, 4,4'-diaminodiphenyl sulfone, 4,4'-aromatic diamines diaminodiphenyl ether or the like, etc. alone, or can be added any mixture thereof during the polycondensation reaction.

  Although it will not specifically limit if it is a range which does not impair the effect of this invention as a compounding quantity of said other diamine component, It is preferable that it is 5 mol% or less with respect to the total amount of a diamine component.

[Production method of polyamide resin]
The polyamide resin used in the present invention can be produced by any method known as a method for producing polyamide. According to the study by the present inventors, it is preferable to polymerize the polyamide resin by subjecting diamine and oxalic acid diester to a polycondensation reaction in a batch or continuous manner. Specifically, it is preferable to carry out in the order of (i) pre-polycondensation step and (ii) post-polycondensation step as shown by the following operations.

  (I) Pre-polycondensation step: First, the inside of the reactor is purged with nitrogen, and then diamine (diamine component) and oxalic acid diester (oxalic acid source) are mixed. When mixing, a solvent in which both the diamine and the oxalic acid diester are soluble may be used. The solvent in which both the diamine component and the oxalic acid source are soluble is not particularly limited, but toluene, xylene, trichlorobenzene, phenol, trifluoroethanol, and the like can be used, and particularly, toluene can be preferably used. For example, after heating the toluene solution which melt | dissolved diamine to 50 degreeC, oxalic acid diester is added with respect to this. At this time, the charging ratio of the oxalic acid diester and the diamine is oxalic acid diester / the diamine, 0.8 to 1.5 (molar ratio), preferably 0.91 to 1.1 (molar ratio), more preferably 0. .99 to 1.01 (molar ratio).

  While stirring and / or nitrogen bubbling in the reactor charged with the above raw materials, the temperature is raised under normal pressure. The reaction temperature is preferably controlled so that the final temperature reaches 80 to 150 ° C., preferably 100 to 140 ° C. The reaction time at the final temperature reached is 3-6 hours.

  (Ii) Post-polycondensation step: In order to further increase the molecular weight, the polymer produced in the pre-polycondensation step is gradually heated in the reactor under normal pressure. In the temperature rising process, the final temperature of the prepolycondensation step, that is, from 80 to 150 ° C, is finally 220 ° C to 300 ° C, preferably 230 ° C to 280 ° C, more preferably 240 ° C to 270 ° C. Let reach the range. It is preferable to carry out the reaction for 1 to 8 hours including the temperature raising time, preferably 2 to 6 hours. Furthermore, in the post-polymerization step, polymerization can be performed under reduced pressure as necessary. The preferable final ultimate pressure in the case of performing the vacuum polymerization is less than 0.1 MPa to 13.3 Pa.

  Next, the specific example of the manufacturing method of the polyamide resin used for this invention is demonstrated. First, the raw oxalic acid diester is charged into the container. The container is not particularly limited as long as it can withstand the temperature and pressure of the polycondensation reaction to be performed later. Thereafter, the container is heated to a temperature at which it is mixed with the raw material diamine, and then the diamine is injected to start the polycondensation reaction. The temperature at which the raw materials are mixed is not particularly limited as long as it is a temperature that is not lower than the melting point and lower than the boiling point of the oxalic acid diester and diamine, and the polyoxamide generated by the polycondensation reaction of the oxalic acid diester and diamine does not thermally decompose. For example, it consists of a mixture of 1,9-nonanediamine and 2-methyl-1,8-octanediamine, and the molar ratio of 1,9-nonanediamine and 2-methyl-1,8-octanediamine is 1:99 to 99: In the case of a polyoxamide resin using diamine 1 and dibutyl oxalate as raw materials, the mixing temperature is preferably 15 ° C to 240 ° C. Moreover, since the molar ratio of 1,9-nonanediamine and 2-methyl-1,8-octanediamine is 5:95 to 90:10, it is liquid at room temperature or liquefied only by heating to about 40 ° C. It is more preferable because it is easy to handle. When the mixing temperature is equal to or higher than the boiling point of the alcohol produced by the condensation reaction, it is desirable to use a container equipped with a device for distilling and condensing the alcohol. In addition, when pressure polymerization is performed in the presence of an alcohol generated by a condensation reaction, a pressure vessel is used. The charging ratio of oxalic acid diester and diamine is oxalic acid diester / diamine as described above, 0.8 to 1.2 (molar ratio), preferably 0.91 to 1.09 (molar ratio), more preferably 0.98. -1.02 (molar ratio).

  Subsequently, the inside of the container is heated to a temperature not lower than the melting point of the polyoxamide resin and not higher than the temperature at which it is not thermally decomposed. For example, a diamine and shu comprising 1,9-nonanediamine and 2-methyl-1,8-octanediamine, and the molar ratio of 1,9-nonanediamine and 2-methyl-1,8-octanediamine is 85:15. In the case of a polyoxamide resin using dibutyl acid as a raw material, the melting point is 235 ° C., so it is preferable to raise the temperature from 240 ° C. to 280 ° C. (pressure is 2 MPa to 4 MPa). While distilling off the produced alcohol, the polycondensation reaction is continued under an atmospheric pressure of nitrogen or reduced pressure as necessary. When the raw materials are mixed in a pressure vessel and subjected to pressure polymerization in the presence of an alcohol produced by a condensation reaction, the pressure is first released while the produced alcohol is distilled off. Thereafter, the polycondensation reaction is continued under an atmospheric pressure of nitrogen or reduced pressure as necessary. The preferable final pressure in the case of carrying out the vacuum polymerization is 760 to 0.1 Torr. The temperature is preferably 240 to 280 ° C. The alcohol is cooled and liquefied by a water-cooled condenser and recovered.

  The molecular weight of the polyamide resin used in the present invention is 1.0 to 6.0 g, more preferably 2.0 to 5 relative viscosity ηr measured at 25 ° C. using a 1.0 g / dl 96% concentrated sulfuric acid solution. .5, particularly preferably having a molecular weight in the range of 2.5 to 4.5. If the molecular weight is low, the melt viscosity tends to be low and not suitable for hollow molding. On the other hand, when the molecular weight increases, the melt viscosity increases and the melt moldability tends to deteriorate.

  The polyamide resin used in the present invention uses oxalic acid as the carboxylic acid component and copolymerizes 1,9-nonanediamine and 2-methyl-1,8-octanediamine as the diamine component, so that oxalic acid and 1,9-nonanediamine are copolymerized. The relative viscosity can be increased, that is, the molecular weight can be increased as compared with the polyamide made of The moldable temperature range represented by the difference (Td−Tm) between the 1% weight loss temperature (hereinafter abbreviated as Td) and the melting point (hereinafter abbreviated as Tm), which is a substantial thermal decomposition index, is oxalic acid. And a polyamide composed of 1,9-nonanediamine, preferably 50 ° C. or higher, more preferably 60 ° C. or higher, and even 90 ° C. or higher. The polyamide resin used in the present invention has a Td of preferably 280 ° C. or higher, more preferably 300 ° C. or higher, still more preferably 320 ° C. or higher, and has high heat resistance.

Layered Silicate The electrophotographic member of the present invention can produce an electrophotographic member having excellent surface smoothness and dimensional stability only with the above-mentioned polyamide resin, but more accurate dimensional stability is required. In application, the electrophotographic member of the present invention may further contain a layered silicate.
Further, by adding a layered silicate, it is possible to improve the rigidity, weather resistance and / or heat resistance and barrier property against liquid or vapor of the electrophotographic member produced from the electrophotographic member of the present invention.

  The layered silicate is preferably a flat plate having a side length of 0.002 to 1 μm and a thickness of 6 to 20 mm. Moreover, it is preferable that the said layered silicate is a thing disperse | distributed uniformly, each layer maintaining the interlayer distance of about 20 mm or more in the above-mentioned polyamide resin.

  Here, “interlayer distance” refers to the distance between the centroids of the plate-like layered silicate, and “uniformly dispersed” means that each layer exists mainly in a random state, and the layered silicate 50% by mass or more, preferably 70% by mass or more, is dispersed in a single layer without forming a multilayer.

  The amount of the layered silicate is not particularly limited as long as the effect of the layered silicate is exhibited, but is preferably 0.05 to 10 with respect to 100 parts by mass of the polyamide resin described above. It is 0.05 parts by mass, more preferably 0.05-8 parts by mass, particularly preferably 0.05-5 parts by mass. When the ratio of the layered silicate is lowered, the effect of the layered silicate is not exhibited, and when the ratio is increased, the melt viscosity becomes extremely high, so that the moldability is deteriorated or the impact resistance is lowered. There is.

  As a raw material of the said layered silicate, the layered phyllosilicate mineral comprised from the layer of magnesium silicate or an aluminum silicate, ie, the aluminum silicate phyllosilicate, or the magnesium silicate phyllosilicate can be illustrated. Specific examples include smectite clay minerals such as montmorillonite, saponite, beidellite, nontronite, hectorite, and stevensite, vermiculite, and halloysite. It may be what was done.

  Moreover, in order to disperse the layered silicate in the polyamide resin, a swelling agent is usually used. The swelling agent has a role of expanding the interlayer of the clay mineral and a role of giving the clay mineral a force for taking up the interlayer polymer. In the present invention, it is preferable to use 1,9-nonanediamine and 2-methyl-1,8-octanediamine as the swelling agent.

  The layered silicate is preferably pulverized using a mixer, a ball mill, a vibration mill, a pin mill, a jet mill, a beating machine, or the like to have a desired shape and size in advance.

  The method for adding the layered silicate is not particularly limited as long as the layered silicate can be uniformly dispersed in the polyamide resin. For example, when the raw material of the layered silicate is a multilayered clay mineral, as disclosed in JP-A-62-74957, the layered silicate is ionized with hydrochloric acid or the like, and a swelling agent such as, for example, 1,9-nonanediamine and 2-methyl-1,8-octanediamine are added to widen the space between the layers of the layered silicate in advance. Next, a polyamide raw material can be introduced between the layers, and the raw materials can be polymerized between the layers.

  Alternatively, an organic compound may be used as a swelling agent, and the layers may be preliminarily spread to about 100 mm or more and melt-mixed with the polyamide resin to disperse each layer in the polyamide resin.

Conductivity imparting agent The conductivity imparting agent used in the present invention is not particularly limited as long as it can be blended with a polyamide resin to impart conductivity.
The conductivity imparting agent is not particularly limited as long as it can impart conductivity, and examples thereof include carbon black, carbon fiber, and metal fiber, and carbon black and carbon fiber are particularly preferably used.

  The carbon black that can be used in the present invention includes all carbon blacks commonly used for imparting conductivity, and preferred carbon blacks include acetylene black obtained by incomplete combustion of acetylene gas, Examples include, but are not limited to, ketjen black, oil black, naphthalene black, thermal black, lamp black, channel black, roll black, disc black, etc., which are manufactured from crude crude oil by furnace-type incomplete combustion. Absent. Among these, acetylene black and furnace black (Ketjen black) are particularly preferably used.

Carbon black is produced in various carbon powders having different characteristics such as particle diameter, surface area, DBP oil absorption, ash content and the like. Although there is no restriction | limiting in the characteristic of this carbon black, What has a favorable chain structure and a large aggregation density is preferable. A large amount of carbon black is not preferable in terms of impact resistance, and from the viewpoint of obtaining excellent electrical conductivity with a smaller amount, the average particle size is preferably 500 nm or less, more preferably 5 to 100 nm, more preferably from 10 to 70 nm, also the surface area (BET method) is preferably ^{10 m} 2 / g or more, more preferably 300 meters ² / g or more, to be 500 to 1500 ² / g Further, the DBP (dibutyl phthalate) oil absorption is preferably 50 ml / 100 g or more, more preferably 100 ml / 100 g, and further preferably 300 ml / 100 g or more. The ash content is preferably 0.5% by weight or less, and more preferably 0.3% by weight or less. The DBP oil absorption here is a value measured by a method defined in ASTM D-2414. Carbon black preferably has a volatile content of less than 1.0% by weight.

  The blending ratio of carbon black is preferably 2 to 35 parts by weight with respect to 100 parts by weight of the entire resin. If the blending ratio of the carbon black is less than 2 parts by weight, it is not preferable because sufficient conductivity cannot be obtained. If the blending ratio exceeds 35 parts by weight, the melt viscosity is high, the fluidity is lowered, and the molding processability is significantly impaired. Therefore, it is not preferable. 2 to 25 parts by weight is preferred.

  As the carbon fiber, pitch-based and PAN-based carbon fibers are used without limitation, but PAN-based carbon fibers are more preferable in view of properties such as physical properties and conductivity.

  The carbon fiber length may be a short fiber having a length of 1000 mm in addition to the short fiber depending on the application, but the fiber length before kneading is preferably 0.1 to 12 mm, particularly preferably 1 to 8 mm.

  Moreover, although the fiber diameter of a carbon fiber has a preferable thing of 5-15 micrometers, a fine carbon fiber can also be used.

  The blending ratio of the carbon fibers is preferably 2 to 30 parts by weight with respect to 100 parts by weight of the whole resin. When the blending ratio exceeds 30 parts by weight, the rigidity is high and the impact resistance is inferior, the smoothness of the surface of the molded product is poor, and the slidability may be lowered. The blending ratio of the carbon fiber is preferably 3 parts by weight or more, more preferably 5 parts by weight or more, and further preferably 7 parts by weight or more. If the blending ratio is small, the electrical conductivity is lowered and it is easy to be charged with static electricity.

The conductivity required for the electrophotographic member of the present invention may vary depending on the application and is not particularly limited. The surface resistance of the polyamide resin is about 10 ¹⁵ Ω. By blending a conductivity imparting agent, for example, it can be reduced to about 10 ¹² to 10 ¹ Ω or less, but a conductivity range of about 10 ³ to 10 ¹⁴ Ω is suitable depending on the application. it is conceivable that.

  Moreover, you may mix | blend a reinforcing fiber with the member for electrophotography of this invention. The reinforcing fiber to be blended is not particularly limited, and examples thereof include inorganic fibers such as glass fiber, carbon fiber, metal fiber, and mineral fiber, and organic fibers such as aramid fiber that is tougher than polyamide resin. By blending the reinforcing fibers, the effect of improving the physical properties such as the strength and creep resistance of the composition is remarkable. Glass fiber and carbon fiber are particularly preferable. Use of carbon fiber has an effect of imparting antistatic performance. About carbon fiber, what was demonstrated previously can be used.

  The glass fiber is not particularly limited. The glass fiber diameter is not limited, but is preferably 5 to 15 μm. The fiber length may be a short fiber or a long fiber depending on the use, but is preferably 5 to 1000 μm.

  The blending ratio of the glass fibers is preferably 35% by mass or less, more preferably 2 to 33% by mass, further preferably 3 to 30% by mass, and particularly preferably 5 to 25% by mass with respect to the entire resin composition. If the blending amount of the glass fiber is small, the improvement in rigidity and creep resistance is lowered, and the bonding with a tube or the like may be deteriorated. On the other hand, when the compounding amount of the glass fiber is increased, the fluidity of the composition is deteriorated, which may cause a short shot or the surface state.

  Furthermore, the electrophotographic material of the present invention may contain a filler, a stabilizer such as a copper compound, a colorant, an ultraviolet absorber, a light stabilizer, an antioxidant, a flame retardant, a crystallization accelerator, a plasticizer, if necessary. An agent, a lubricant and the like can also be added during or after the polycondensation reaction.

[Electrophotographic materials]
The dicarboxylic acid component consists of oxalic acid, the diamine component consists of 1,9-nonanediamine and 2-methyl-1,8-octanediamine, and the moles of 1,9-nonanediamine and 2-methyl-1,8-octanediamine Polyamide resins having a ratio of 1:99 to 99: 1 are included.

The electrophotographic member of the present invention can further contain the following components as optional components in addition to the polyamide resin.
(1) Other polymer The dicarboxylic acid component used in the present invention is composed of oxalic acid, the diamine component is composed of 1,9-nonanediamine and 2-methyl-1,8-octanediamine, and 1,9-nonanediamine and 2- The polyamide resin having a molar ratio with methyl-1,8-octanediamine of 1:99 to 99: 1 can be partially substituted with other polymer components as long as the effects of the present invention are not impaired. Examples of other polymer components include other polyamides such as polyoxamide, aromatic polyamide, aliphatic polyamide, alicyclic polyamide, and polymers other than polyamide, such as thermoplastic polymers and elastomers.

Although it will not specifically limit if it is the range which does not impair the effect of this invention as said substitution ratio by said other polymer, Preferably it is less than 50 mass%, More preferably, it is 30 mass% or less.
In the following, when simply referred to as “polyamide” or “polyamide resin”, the dicarboxylic acid component consists of oxalic acid, the diamine component consists of 1,9-nonanediamine and 2-methyl-1,8-octanediamine, And it shall refer to the polyamide resin whose molar ratio of 1,9-nonanediamine and 2-methyl-1,8-octanediamine is 1: 99-99: 1.

(2) Additive The electrophotographic member of the present invention can contain other additives as long as the effects of the present invention are not impaired. Other additives include, for example, pigments, dyes, colorants, heat resistance agents, antioxidants, weathering agents, UV absorbers, light stabilizers, lubricants, crystal nucleating agents, crystallization accelerators, mold release agents, and charging agents. Examples thereof include stabilizers, plasticizers, stabilizers such as copper compounds, antistatic agents, flame retardants, glass fibers, lubricants, fillers, reinforcing fibers, reinforcing particles, and foaming agents.

  The method for adding the other polymer and the additive is not particularly limited as long as each of them can be dispersed in the polyamide resin, and the polyamide resin can be added to the polyamide resin at any time without impairing its effect. Can be added. For example, the other polymers and additives can be added immediately after the post polycondensation step of the polyamide resin.

[Electrophotographic parts]
The electrophotographic component can be produced by molding the electrophotographic member of the present invention by, for example, injection molding, extrusion molding, blow molding, compression molding or the like.
The electrophotographic member of the present invention can be obtained by inflation extrusion molding. By this method, a molded product having an arbitrary diameter and a thickness of 30 to 1000 μm is obtained. The electrophotographic member thus formed does not have a seam, and is useful as an intermediate transfer belt, a transfer conveyance belt, and the like used for an electrophotographic copying machine, a printer, a fax machine, and the like. Further, similarly, a member for electrophotography formed into a cylindrical shape is coated on a conductive support, and heated and fused to form a conductive roll. Or it can also be set as an electroconductive roll by carrying out melt coating of the electroconductive polyamide composition continuously on an electroconductive support body with an extruder. The conductive roll is useful as, for example, a cleaning roll, a charging roll, a developing roll, or a transfer roll.

Furthermore, the electrophotographic member of the present invention formed into a cylindrical shape with the above-described thickness of 30 to 1000 μm has an average surface roughness Ra of 1 μm or less, and has a maximum and minimum surface resistivity in the same plane. The ratio is preferably 10 times or less. When Ra is 1 μm or less, when the electrophotographic member of the present invention is used for an intermediate transfer belt, a charging roll, a developing roll, a transfer roll, etc., the sharpness of the generated image is remarkably improved. Further, since the ratio of the maximum value and the minimum value of the surface resistivity in the same plane is 10 times or less, the electrophotographic member of the present invention has a uniform attractive force for attracting toner and paper, and the intermediate transfer belt, transfer conveyance It can be more suitably used as an electrophotographic member such as a belt, a cleaning roll, a charging roll, a developing roll, and a transfer roll.
In order to set the Ra of the electrophotographic member to 1 μm or less, it is effective to set the temperature of the annular die at the time of molding slightly higher. Further, in order to suppress the ratio of the maximum value and the minimum value of the volume resistivity in the same plane of the electrophotographic member to 10 times or less, it is effective to suppress the aggregate size of the conductivity imparting agent to be small. Specifically, a method of molding so that the average diameter of the aggregate is 3 μm or less, more preferably 2 μm or less is effective.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated, this invention is not limited to these Examples.

[Physical property measurement, molding, evaluation method]
The characteristic value was measured by the following method.
(1) Relative viscosity (ηr)
ηr was measured at 25 ° C. with an Ostwald viscometer using a 96% sulfuric acid solution of polyamide (concentration: 1.0 g / dl).

(2) Melting point (Tm) and crystallization temperature (Tc)
Tm and Tc were measured under a nitrogen atmosphere using a PYRIS Diamond DSC manufactured by PerkinELmer. The temperature was raised from 30 ° C. to 270 ° C. at a rate of 10 ° C./min (referred to as a temperature rise first run), held at 270 ° C. for 3 minutes, and then lowered to −100 ° C. at a rate of 10 ° C./min (temperature fall first). Then, the temperature was raised to 270 ° C. at a rate of 10 ° C./min (called a temperature raised second run). From the obtained DSC chart, the exothermic peak temperature of the temperature decrease first run was Tc, and the endothermic peak temperature of the temperature increase second run was Tm.

(3) 1% weight loss temperature (Td)
Td was measured by thermogravimetric analysis (TGA) using THERMOGRAVIMETRIC ANALYZER TGA-50 manufactured by Shimadzu Corporation. The temperature was raised from room temperature to 500 ° C. at a rate of 10 ° C./min under a nitrogen stream of 20 ml / min, and Td was measured.
(4) Melt viscosity Melt viscosity was measured by attaching a 25 mm cone plate to a melt viscoelasticity measuring device ARES manufactured by TA Instruments Japan Co., Ltd., at 250 ° C. in nitrogen and at a shear rate of 0.1 s ⁻¹ . Measured under conditions.

(5) Film formation A film was formed from the pellets using a vacuum press TMB-10 manufactured by Toho Machinery Co., Ltd. After being melted by heating at 260 ° C. for 5 minutes under a reduced pressure atmosphere of 500 to 700 Pa, the film was formed by pressing at 5 MPa for 1 minute. Next, the reduced-pressure atmosphere was returned to normal pressure, and then cooled and crystallized at room temperature of 5 MPa for 1 minute to obtain a film.

(6) Saturated water absorption rate A film (dimensions: 20 mm × 10 mm, thickness 0.25 mm; mass of about 0.05 g) formed under the conditions of (5) above is immersed in ion-exchanged water at 23 ° C., and every predetermined time. The film was taken out and the mass of the film was measured. When the rate of increase in the film mass lasts 3 times within the range of 0.2%, it is judged that the absorption of moisture into the polyamide resin film has reached saturation, and the mass (Xg) of the film before being immersed in water The saturated water absorption (%) was calculated from the mass (Yg) of the film when reaching saturation with the following equation (1).
Saturated water absorption (%) = 100 × (Y−X) / X (1)

(7) Chemical Resistance After immersing the polyamide hot press film obtained by the present invention in the chemicals listed below for 7 days at 23 ° C., changes in the residual mass (%) and appearance of the film were observed. Concentrated hydrochloric acid, 64% sulfuric acid, and glacial acetic acid were tested.

(8) Hydrolysis resistance A hot press film is prepared from the injection molding material of the present invention, and the hot press film is placed in an autoclave, and water (pH = 7), 0.5 mol / l sulfuric acid (pH = 1) or In a 1 mol / l sodium hydroxide aqueous solution (pH = 14), the residual weight ratio (%) and appearance change after treatment at 121 ° C. for 60 minutes were examined.

(9) Mechanical properties [1] to [4] shown below were measured by molding the following test pieces by injection molding at a resin temperature of 260 ° C. and a mold temperature of 80 ° C. The data measured at 23 ° C. after the molding was shown in the table as dry, the moisture was adjusted at a humidity of 65% RH after molding, and the data measured at 23 ° C. was shown in the table.
[1] Tensile yield strength or tensile strength: Measured according to ASTM D638 using a Type I test piece described in ASTM D638.
[2] Flexural modulus: Measured according to ASTM D790 using a test piece with a test piece size of 3.2 mm × 12.7 mm × 127 mm.
[3] Izod impact strength: Measured at 23 ° C. in accordance with ASTM D256 using a test piece with a test piece size of 3.2 mm × 12.7 mm × 127 mm.
[4] Deflection temperature under load (thermal deformation temperature): Measured at a load of 1.82 MPa in accordance with ASTM D648 using a test piece having a test piece size of 3.2 mm × 12.7 mm × 127 mm.

(10) Water absorption rate The water absorption rate (%) was calculated according to the measurement method of (6) saturated water absorption rate, except that it was placed under conditions of 23 ° C. and humidity 65% RH.

(11) Average surface roughness The average surface roughness of the molded product was measured at a vertical magnification of 50000 times using a Surfcom 570A type surface shape measuring device manufactured by Tokyo Seimitsu Co., Ltd. In the measurement, a measuring needle having a radius of 5 μm was scanned at a speed of 0.03 mm / second in the direction perpendicular to the flow direction of the molded product.

[Example 1: Production of PA92-1]
Oxalic acid in a pressure vessel with a volume of 150 liters equipped with a stirrer, thermometer, torque meter, pressure gauge, raw material inlet directly connected with a diaphragm pump, nitrogen gas inlet, pressure relief port, pressure regulator and polymer outlet The operation of charging 28.40 kg (140.4 mol) of dibutyl, pressurizing the inside of the pressure vessel to 0.5 MPa with nitrogen gas having a purity of 99.9999%, and then releasing nitrogen gas to normal pressure is performed 5 After repeated nitrogen substitution, the system was heated while stirring under a sealing pressure. After adjusting the temperature of dibutyl oxalate to 100 ° C. over about 30 minutes, 18.89 kg (119.3 mol) of 1,9-nonanediamine and 3.34 kg (21.1 mol) of 2-methyl-1,8-octanediamine were obtained. ) (Molar ratio of 1,9-nonanediamine and 2-methyl-1,8-octanediamine is 85:15) into a reaction vessel by a diaphragm pump at a flow rate of 1.49 liters / minute for about 17 minutes. The temperature was raised simultaneously with the supply. The internal pressure in the pressure vessel immediately after the supply increased to 0.35 MPa by butanol generated by the polycondensation reaction, and the temperature of the polycondensate increased to about 170 ° C. Thereafter, the temperature was raised to 235 ° C. over 1 hour. Meanwhile, the internal pressure was adjusted to 0.5 MPa while extracting the generated butanol from the pressure relief port. Immediately after the temperature of the polycondensate reached 235 ° C., butanol was extracted from the pressure release port over about 20 minutes, and the internal pressure was brought to normal pressure. From the normal pressure, the temperature was raised while flowing nitrogen gas at 1.5 liters / minute, the temperature of the polycondensate was brought to 260 ° C. over about 1 hour, and the reaction was carried out at 260 ° C. for 4.5 hours. . Thereafter, stirring was stopped, the inside of the system was pressurized to 1 MPa with nitrogen and allowed to stand for about 10 minutes, then released to an internal pressure of 0.5 MPa, and the polycondensate was extracted in a string form from the lower outlet of the pressure vessel. The string-like polymer was immediately cooled with water, and the water-cooled string-like resin was pelletized with a pelletizer. The obtained polyamide was a white tough polymer, and ηr = 3.20.

[Example 2: Production of PA92-2]
A mixture of 17.62 kg (111.3 mol) of 1,9-nonanediamine and 4.45 kg (28.1 mol) of 2-methyl-1,8-octanediamine (1,9-nonanediamine and 2-methyl-1,8 A polyamide was obtained by reacting in the same manner as in Example 1 except that the octanediamine molar ratio was 80:20). The obtained polyamide was a white tough polymer and had ηr = 3.10.

[Example 3: Production of PA92-3]
A mixture of 11.11 kg (70.2 mol) of 1,9-nonanediamine and 11.11 kg (70.2 mol) of 2-methyl-1,8-octanediamine (1,9-nonanediamine and 2-methyl-1,8 -Polyamide was obtained by reacting in the same manner as in Example 1 except that the octanediamine molar ratio was 50:50). The obtained polymer was a white tough polymer, and ηr = 3.35.

[Example 4: Production of PA92-4]
A mixture of 6.67 kg (42.1 mol) of 1,9-nonanediamine and 15.56 kg (98.3 mol) of 2-methyl-1,8-octanediamine (1,9-nonanediamine and 2-methyl-1,8 -Polyamide was obtained by reacting in the same manner as in Example 1 except that the octanediamine molar ratio was 30:70). The obtained polyamide was a white tough polymer, and ηr = 3.55.

[Example 5: Production of PA92-5]
A mixture of 1.33 kg (8.4 mol) of 1,9-nonanediamine and 20.88 kg (131.9 mol) of 2-methyl-1,8-octanediamine (1,9-nonanediamine and 2-methyl-1,8 -Polyamide was obtained by carrying out the reaction in the same manner as in Example 1 except that the molar ratio of octanediamine was 6:94). The obtained polymer was a white tough polymer, and ηr = 3.53.

[Example 6: Production of PA92-6]
A mixture of 1.33 kg (8.4 mol) of 1,9-nonanediamine and 20.88 kg (131.9 mol) of 2-methyl-1,8-octanediamine (1,9-nonanediamine and 2-methyl-1,8 -The octanediamine molar ratio was 6:94), and the reaction was carried out in the same manner as in Example 1 except that the internal pressure by extracting butanol was maintained at 0.25 MPa to obtain polyamide. The obtained polymer was a white tough polymer, and ηr = 4.00.

[Comparative Example 1: Production of PA92-0]
Using only 22.25 kg (140.4 mol) of 1,9-nonanediamine as a diamine raw material, a reaction was carried out in the same manner as in Example 1 to obtain a polyamide. The obtained polymer was a yellowish white polymer, and ηr = 2.78.

Table 1 shows the characteristic data of PA92-1 to PA92-6 prepared in Examples 1 to 6 and PA92-0 prepared in Comparative Example 1.
Moreover, the characteristic data of commercially available products PA6 (Ube Industries, UBE nylon 1015B) and PA66 (Ube Industries, UBE nylon 2020B) are shown in Table 1 as Comparative Examples 2 and 3, respectively.

  From Table 1, the injection molding material of the present invention has low water absorption compared to materials such as nylon 6 and nylon 66, excellent chemical resistance and hydrolysis resistance, and excellent mechanical properties under wet conditions. , And producing a tough molded body having a wider moldable temperature range and better melt moldability and higher molecular weight than polyamide resin (PA92-0) using 1,9-nonanediamine alone as a diamine component You can see that

[Examples 7 to 19, Comparative Examples 4 to 10]
Polyamides PA92-1 to PA92-6 and PA92-0 manufactured in Examples 1 to 6 and Comparative Example 1, commercially available nylon 6 (UBE Nylon 1015B; U6 manufactured by Ube Industries), nylon 66 (UBE Nylon 2020B manufactured by Ube Industries) PA66) and nylon 12 (UBESTA3020U; PA12), organic montmorillonite (Nanocor, Nanomer 30TC), carbon fiber (Toho Tenax Co., Ltd. Besfite HTA-C6NR (fiber diameter 7 μm), Ketjen Black (Ketjen) The mixture of the ratio shown in Table 2 was created using EC600JD (Black International).

Furthermore, these mixtures were melt-kneaded at 260 ° C. (290 ° C. for PA66, 230 ° C. for nylon 12) using a twin-screw kneader with a cylinder diameter of 40 mm, extruded into a strand, cooled in a water tank, and then used with a pelletizer. Pellets were made.
A seamless belt-like film having a thickness of 200 μm was prepared from the obtained pellets using an inflation extrusion molding method.

  Using the film obtained above, the surface resistance value, mechanical properties, chemical resistance, molded product smoothness and the like were evaluated. The evaluation results are shown in Table 2. The smoothness of the molded article was determined as ◯ when Ra was 1 μm or less, and x when Ra was larger than 1 μm.

  The electrophotographic member of the present invention is an electrophotographic member excellent in surface smoothness and dimensional stability, excellent in chemical resistance and hydrolysis resistance, compared to an electrophotographic member such as nylon 6. And, it is possible to produce a tough molded body having a wider moldable temperature range and excellent melt moldability than that of a material using 1,9-nonanediamine alone as a diamine component, and capable of increasing the molecular weight. Since it can be used in electrophotographic parts that are required to have excellent dimensional stability, it is industrially useful.

JP 2006-57033 A Special table 5-506466

S. W. Shalaby., J. Polym. Sci., 11, 1 (1973) L. Franco et al., Macromolecules., 31, 3912 (1988)

Claims (6)

  An electrophotographic member comprising a polyamide resin and a layered silicate dispersed in the polyamide resin and blended with a conductivity imparting material, wherein the dicarboxylic acid component is composed of oxalic acid, and the diamine component is 1,9- Comprising a polyamide resin consisting of nonanediamine and 2-methyl-1,8-octanediamine and having a molar ratio of 1,9-nonanediamine to 2-methyl-1,8-octanediamine of 1:99 to 99: 1 Electrophotographic member.   The relative viscosity (ηr) of the polyamide resin measured at 25 ° C. using a polyamide resin solution having a concentration of 1.0 g / dl using 96% sulfuric acid as a solvent is 1.8 to 6.0. The electrophotographic member according to 1.   1% weight loss temperature in thermogravimetric analysis of the polyamide resin measured at a heating rate of 10 ° C./min in a nitrogen atmosphere, and differential scanning calorimetry measured at a heating rate of 10 ° C./min in a nitrogen atmosphere. The member for electrophotography according to claim 1 or 2, wherein the temperature difference from the melting point measured by (1) is 50 ° C or more.   The member for electrophotography according to any one of claims 1 to 3, wherein a molar ratio of 1,9-nonanediamine to 2-methyl-1,8-octanediamine is 5:95 to 95: 5.   The member for electrophotography according to any one of claims 1 to 4, wherein a content of the layered silicate is 0.05 to 10 parts by mass with respect to 100 parts by mass of the polyamide resin.   The member for electrophotography according to any one of claims 1 to 5, wherein the layered silicate is an aluminum silicate phyllosilicate or a magnesium silicate phyllosilicate.