JP2576065B2 - Semiconductive polymer composition - Google Patents

Description

The present invention relates to a semiconductive polymer composition prepared by a sol-gel method.

2. Description of the Related Art Conventionally, many so-called compound semiconductors, mainly Si and Ge, have been known as semiconductive materials. on the other hand,
It is also known that certain metal oxides exhibit semiconductivity. However, since these materials are generally prepared by a dry film forming method, it is difficult to obtain a device having a large area, and the cost is high.

On the other hand, the development of semiconductive materials made of organic materials has also been actively promoted in recent years, and progress has been made in some fields until practical use. In particular, excellent results have been produced, such as doping a low molecular compound, for example, a charge transport material, into a high molecular polymer to obtain an organic electrophotographic photoreceptor. A semiconductive material using an organic material has many advantages, such as easy area enlargement and low cost. However, there are drawbacks that the conductivity is easily affected by moisture absorbed or impurity ions in the high molecular polymer, and the weather resistance is poor, and the hardness and wear resistance are poor.

Problems to be Solved by the Invention Incidentally, in recent years, a method of forming a metal oxide semiconductor by a sol-gel method has been proposed, and a large-area device can be obtained at low cost. However, a metal oxide exhibiting semiconductivity is difficult to form a uniform film, and a metal oxide easily forming a uniform film is insulative.

On the other hand, it has been proposed to obtain a semiconductor conductive material by doping an organic molecule into a metal oxide in which a uniform film is easily formed. (J. Appl. Phy., 58, 9, 1, p3559 (1985) )), As the organic molecules to be doped, only alcohol-soluble or water-soluble organic molecules can be used, and their applications have been limited.

The present invention has been made in view of the above situation.

Accordingly, an object of the present invention is to provide a semiconductive polymer composition containing an organic compound stably prepared by a sol-gel method.

Means and Action for Solving the Problems The present inventors have studied and found that by substituting a part of the alkoxy group of the metal alkoxide with a hydrophobic substituent having an affinity for an organic compound that disperses, the hydrophobicity of the metal alkoxide is improved. It has been found that the substituent forms a gel in which micelles are aggregated, has an affinity for organic compound molecules, and enables various organic compound molecules to be compatible in the gel. It has been found that the conductivity of the metal oxide can be freely controlled by selecting the organic compound to be contained, and the present invention has been completed.

The first of the semiconductive polymer compositions of the present invention comprises the following general formulas (I), (II) and (III) (Wherein, M ₁ represents a trivalent metal atom, M ₂ represents a tetravalent metal atom or a carbon atom, and R ₁ , R ₂ and R ₃ each represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. Where R ₁ ,
At least one of R ₂ and R ₃ represents an alkyl group having 1 to 6 carbon atoms, and X ₁ and X ₂ each have an alkyl group having 5 or more carbon atoms which may have a substituent, an aryl group, an aralkyl group,
An acyl group, a heterocyclic group, or an unsaturated hydrocarbon group, or X ₁ and X ₂ represent a group bonded to each other to form a ring structure). characterized in that it comprises a charge transport material having the seed of the matrix formed by the condensation polymerization, and the affinity with the group X ₁ or X ₂ contained in the metal alkoxide.

The second one is at least one metal alkoxide selected from the group represented by the above general formulas (I), (II) and (III) and the following general formulas (IV) and (V) (Wherein, M ₃ represents a trivalent metal atom, M ₄ represents a tetravalent metal atom or a carbon atom, and R ₄ , R ₅ and R ₆ are each a hydrogen atom or a C 1 -C 4 Represents an alkyl group;
Is a hydroxyl group, an alkoxy group having 1 to 4 carbon atoms, a halogen atom, an amino group, an alkyl group having 1 to 4 carbon atoms which may have a substituent, an aryl group having a substituent, an acyl group,
A heterocyclic group or an unsaturated hydrocarbon group), a matrix formed by polycondensation with at least one metal alkoxide selected from the group consisting of: and a group X ₁ or X ₂ contained in the metal alkoxide And a charge transporting material having an affinity for.

In the present specification, “metal alkoxide” refers to M ₂ and M in the above general formulas (II), (III) and (V).
It is defined as meaning when ₄ represents a carbon atom.

In the present invention, the metal atom of the metal alkoxide in the above general formulas (I) to (V) used as a raw material is selected from Al, B, Ga, Y, Fe, Si, Ge, Sn, Ti and Zr. Is preferred.

The following are examples of metal alkoxides that can be suitably used for producing the semiconductive polymer composition of the present invention.

Metal alkoxide represented by the general formula _{(I): C 5 H 11} -Al (OCH 3) 2, C 6 H 13 -Al (OCH 3) 2 C 7 H 15 -Al (OCH 3) 2, C 8 H 17 _{-Al (OCH 3) 2 C 9} H 19 -Al (OCH 3) 2, C 10 H 21 -Al (OCH 3) 2 C 15 H 31 -Al (OCH 3) 2, C 20 H 41 -Al (OCH _{3) 2 C 25 H 51 -Al} (OCH 3) 2, C 10 H 21 -Al (OC 2 H 5) 2 C 20 H 41 -Al (OC 2 H 5) 2, C 25 H 51 -Al (OC _{2 H 5) 2 C 10 H} 21 -Al (OC 3 H 7) 2, C 10 H 21 -Al (OC 4 H 9) 2 C 10 H 21 -Al (OC 5 H 11) 2, _{CH 2 = CH (CH 2)} 3 -Al (OCH 3) 2, CH 3 CH = CH (CH 2) 2 -Al (OCH 3) 2, CH 2 = CHCH 2 CH = CH-Al (OCH 3) 2 _{, NH 2 (CH 2) 5} -Al (OCH 3) 2, C 5 H 11 -B (OCH 3) 2 C 10 H 21 -B (OCH 3) 2, _{C 5 H 11 -Ga (OCH 3} ) 2, C 10 H 21 -Ga (OCH 3) 2 _{C 5 H 11 -Y (OCH 3} ) 2 C 10 H 21 -Y (OCH 3) 2 _{C 5 H 11 -Fe (OCH 3} ) 2 C 10 H 21 -Fe (OCH 3) 2 Formula (II) metal represented by _{alkoxide: C 5 H 11 -Si (OCH} 3) 3, C 10 H 21 -Si (OCH 3) 3 C 15 H 31 -Si (OCH 3) 3, C 20 H 41 _{-Si (OCH 3) 3 C 5} H 11 -Si (OC 2 H 5) 3, C 20 H 41 -Si (OC 2 H 5) 3 C 20 H 41 -Si (OC 3 H 7) 3, C 20 _{H 41 -Si (OC 4 H 9} ) 3 C 20 H 41 -Si (OC 5 H 11) 3, CH ₂ = CHCH ₂ CH = CHSi (OCH ₃ ) ₃ , NH ₂ (CH ₂ ) ₅ Si (OCH ₃ ) ₃ , CH ₂ CHCHSi (OC ₂ H ₅ ) ₃ , CH ₂ CHCHSi (OCH ₃ ) ₃ HSC ₃ H ₆ Si (OCH) ₃ , NH ₂ C ₂ H ₄ NHC ₃ H ₆ Si (OCH ₃ ) ₃ , NH ₂ CONHC ₃ H ₆ Si (OC ₂ H ₅ ) ₃ , NH ₂ C ₃ H ₆ Si ( OC ₂ H _{5) 3,} ClC ₃ H ₆ Si (OCH ₃ ) ₃ , _{C 5 H 11 -C (OCH 3} ) 3, C 15 H 31 -C (OCH 3) 3 _{C 5 H 11 -Ge (OCH 3} ) 3 C 20 H 41 -Ge (OCH 3) 3, _{C 5 H 11 -Sn (OCH 3} ) 3, C 20 H 41 -Sn (OCH 3) 3 _{C 5 H 11 -Ti (OCH 3} ) 3 C 20 H 41 -Ti (OCH 3) 3, _{C 5 H 11 -Zr (OCH 3} ) 3, C 20 H 41 -Zr (OCH 3) 3 Metal alkoxide represented by the general formula (III): When the metal alkoxides represented by the general formulas (IV) and (V) are used, the above-mentioned general formulas (I) to (II)
0 to 98 mol% based on the metal alkoxide represented by I)
Used in the range.

The following are examples of the metal alkoxides represented by the general formulas (IV) and (V) used together with the metal alkoxides represented by the general formulas (I) to (III).

Metal alkoxide represented by the general formula (IV): Al (OCH ₃ ) ₃ , Al (OC ₂ H ₅ ) ₃ Al (OC ₃ H ₇ ) ₃ , Al (OC ₄ H ₉ ) ₃ B (OCH ₃ ) ₃ , B (OC ₄ H ₉ ) ₃ , Ga (OCH ₃ ) ₃ , Ga (OC ₄ H ₉ ) ₃ , Y (OCH ₃ ) ₃ , Y (OC ₄ H ₉ ) ₃ , Fe (OCH ₃ ) ₃ , Fe (OC ₄ H ₉ ) ₃ , Metal alkoxide represented by the general formula (V): Si (OCH ₃ ) ₄ , Si (OC ₂ H ₅ ) ₄ Si (OC ₃ H ₇ ) ₄ , Si (OC ₄ H ₉ ) ₄ C (OCH ₃ ) ₄ , C (OC ₄ H ₉ ) ₄ Ge (OCH ₃ ) ₄ , Ge (OC ₄ H ₉ ) ₄ Sn (OCH ₃ ) ₄ , Sn (OC ₄ H ₉ ) ₄ Ti (OCH ₃ ) ₄ , Ti (OC ₄ H ₉ ) ₄ Zr (OCH ₃ ) ₄ , Zr (OC ₄ H ₉ ) ₄ The charge transporting material used in the present invention has an affinity with the group X ₁ (or X ₂ ) of the metal alkoxide, as long as it imparts semiconductivity to the formed film.
Anything can be used. For example, oxadiazole derivatives, pyrazoline derivatives, aromatic tertiary amine compounds, triazine derivatives, hydrazone derivatives,
Examples include quinazoline derivatives, benzofuran derivatives, stilbene derivatives, enamine derivatives, carbazole derivatives, pyrene compounds, cyanovinyl compounds, quinone compounds, ketone compounds, fluorenone compounds, and quinodimethane compounds. These materials can be contained at a content ranging from 0.1 to 99% by volume based on the metal alkoxide.

In order to form the semiconductive polymer composition of the present invention,
The above metal alkoxide, together with a predetermined amount of the charge transporting substance to be contained, is added to a suitable solvent, for example, water, alcohol, or an organic solvent such as toluene, xylene, or halogenated hydrocarbon to cause gelation. Alternatively, after the above-mentioned metal alkoxide is gelled by an appropriate method, a predetermined amount of the charge transport material to be contained is dissolved in an appropriate solvent, and the gel is immersed in the charge transport material. This is performed by impregnating the gel. Further, a catalyst such as an acid can be used, if necessary, in order to promote the gelation reaction. 30 ° C ~
A heat treatment at 1500 ° C. may be performed.

The semiconductive polymer composition of the present invention formed as described above has a state in which the charge transporting substance is dispersed in a matrix formed by condensation polymerization of metal alkoxide. As shown in FIG. 1 (FIG. 1 is a model in the case of silicon), the dispersion state is represented by a group X formed in a matrix composed of a condensation polymer of a metal alkoxide.
₁ (or X ₂₎ micelles structure assembled, it is in the form of a charge-transporting substance A in group X ₁ and affinity captured. Therefore, the charge transport material is contained in the matrix in a stabilized state.

Examples Hereinafter, the present invention will be described with reference to examples.

Example 1 10 parts by weight of tetramethoxysilane (Si (OCH ₃ ) ₄ ), 10 parts by weight of an alkoxysilane represented by the following structural formula, 10 parts by weight of a charge transport material represented by the following structural formula, Is dissolved in 200 parts by weight of cyclohexanone, coated on a Si substrate by a chip coating method, and dried at 150 ° C. for 90 minutes.
A film having a thickness of 1.6 μm was formed.

Next, an electrode made of Au was formed on the formed film by vacuum evaporation, and a sample having a structure of Si / SiO ₂ (surface oxide film) / semiconductive polymer composition / Au was prepared.

An electrometer (Keithk
The measurement of the current-voltage characteristic was performed using ey company type 617). The result is shown in FIG. As apparent from FIG. 2, the film made of the above semiconductive polymer composition exhibited a rectifying action and acted as an n-type semiconductor.

Example 2 A film made of a semiconductive polymer composition was produced in exactly the same manner as in Example 1, except that the charge transport material represented by the following structural formula was used instead of the charge transport material. 1.3 film thickness
μm. The current-voltage characteristics of this sample were measured in exactly the same manner as in Example 1. This sample also exhibited a rectifying action as in Example 1, and acted as an n-type semiconductor.

Example 3 A film made of a semiconductive polymer composition was prepared in exactly the same manner as in Example 1, except that the charge transport material represented by the following structural formula was used instead of the charge transport material. The film thickness is 1.5
μm. The current-voltage characteristics of this sample were measured in exactly the same manner as in Example 1. This sample also exhibited a rectifying action as in Example 1, and acted as a p-type semiconductor.

Comparative Example 1 A film made of a semiconductive polymer composition was produced in the same manner as in Example 1 except that in Example 1, only tetramethoxysilane was used as the alkoxysilane. However, after drying, the added cyano compound was precipitated and a uniform film could not be obtained.

Example 4 A film made of the semiconductive polymer composition shown in Example 1 was formed in the same manner using an aluminum pipe as the conductive substrate. The film thickness was 1.0 μm. This was used as an undercoat layer, and a charge generation layer was formed thereon. That is, a mixture consisting of 90 parts by weight of trigonal selenium (manufactured by Xerox Corporation in the United States), 10 parts by weight of polyvinyl butyral resin, and 300 parts by weight of n-butanol was dispersed using an attritor, and 1 part by weight of the obtained dispersion was dispersed. On the other hand, a liquid diluted by adding 2 parts by weight of n-butanol was applied onto the undercoat layer by drawing, and dried to form a 0.3 μm film. Next, N, N '
-Diphenyl-N, N'-bis (3-methylphenyl)
[1,1'-biphenyl] -4,4'-diamine (4 parts by weight) and a polycarbonate resin (6 parts by weight) are dissolved in toluene (40 parts by weight) to obtain a coating solution. Drying was performed at 60 ° C. for 60 minutes to form a charge transport layer having a thickness of 21 μm.

Various electrophotographic characteristics of the electrophotographic photoreceptor thus obtained were evaluated. The electrophotographic characteristics were measured using an electrophotographic characteristics evaluation device manufactured by Fuji Xerox Co., Ltd., and the following evaluations were made.

The photosensitive member was charged so that the inflow current became −10 μA, and the surface potential of the photosensitive zone one second after the charging was measured. The measured value was VDDP (0). Thereafter, static elimination was performed with a tungsten lamp, the potential after static elimination was measured, and this was defined as residual flow potential VRP (0). Next, the inflow current of the photoreceptor was adjusted so that VDDP became -500 V, and 0.3 seconds after charging, monochromatic light of 550 nm was exposed while changing the amount of light, and 0.7 seconds after exposure (1 second after charging) ) To determine the amount of light at which the potential at -250 V
(0). Next, the inflow current of the photoreceptor is maintained at −10 μA, and charging and discharging are repeated 10,000 times. At that time, the photoreceptor surface potential: VDDP (10000) and the residual potential: VRP (100
0), light sensitivity: E 1/2 (10000) was measured.

 Table 1 shows the obtained results.

Comparative Example 2 Polyamide resin: 10 parts by weight on aluminum pipe
A coating solution consisting of 150 parts by weight of methanol and 40 parts by weight of water is applied by a drawing coating method so that the film thickness after drying becomes 1 μm to form an undercoat layer. An electrophotographic photosensitive member was prepared in exactly the same manner as in Example 4 except for the transport layer. The obtained electrophotographic photosensitive member was evaluated for electrophotographic characteristics in the same manner as in Example 4. The results are shown in Table 1.

As can be seen from the comparison of Examples 1 to 3 and Comparative Example 1,
ADVANTAGE OF THE INVENTION According to this invention, the rectification property of a metal oxide can be controlled and a functional polymer composition can be easily produced.

Furthermore, as can be seen from a comparison between Example 4 and Comparative Example 2, when the polymer composition of the present invention was applied to an undercoat layer of an electrophotographic photoreceptor, an increase in residual potential due to repetitive action was observed.
It is possible to provide an electrophotographic photoreceptor without a decrease in light sensitivity. This is considered to be because the undercoat layer of the present invention does not cause the accumulation of space charge that causes an increase in residual potential / a decrease in photosensitivity.

Effect of the Invention In the semiconductive polymer composition of the present invention, the charge transport material having a hydrophobic group is in a state stably contained in a matrix of a polycondensate of a metal alkoxide, It is possible to provide a material that is hardly affected by moisture absorbed or impurity ions in a high-molecular polymer. In addition, a large-area one can be easily obtained, which is advantageous in terms of cost, and also excellent in terms of weather resistance, hardness, wear resistance and the like.

Therefore, the semiconductive polymer composition of the present invention is useful, for example, as a semiconductor transistor element, a switching element, an electrophotographic material, and the like.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a model of the structure of the semiconductive polymer composition of the present invention, and FIG. 2 is a graph showing current-voltage characteristics of the semiconductor device of Example 1.

Claims (3)

(57) [Claims] (1) The following general formulas (I), (II) and (III) (Wherein, M ₁ represents a trivalent metal atom, M ₂ represents a tetravalent metal atom or a carbon atom, and R ₁ , R ₂ and R ₃ each represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. Where R ₁ ,
At least one of R ₂ and R ₃ represents an alkyl group having 1 to 6 carbon atoms, and X ₁ and X ₂ each have an alkyl group having 5 or more carbon atoms which may have a substituent, an aryl group, an aralkyl group,
At least one of a metal alkoxide selected from the group consisting of: an acyl group, a heterocyclic group, or an unsaturated hydrocarbon group, or X ₁ and X ₂ represent a group bonded to each other to form a ring structure. matrix formed by condensation polymerization of the seed, and the semiconductive polymer composition characterized by containing a charge transporting substance having an affinity with the group X ₁ or X ₂ contained in the metal alkoxide. 2. The following general formulas (I), (II) and (III) (Wherein, M ₁ , M ₂ , R ₁ , R ₂ , R ₃ , X ₁ and X ₂ have the same meanings as described above), and at least one metal alkoxide selected from the group represented by: The following general formulas (IV) and (V) (Wherein, M ₃ represents a trivalent metal atom, M ₄ represents a tetravalent metal atom or a carbon atom, and R ₄ , R ₅ and R ₆ are each a hydrogen atom or a C 1 -C 4 Represents an alkyl group;
Is a hydroxyl group, an alkoxy group having 1 to 4 carbon atoms, a halogen atom, an amino group, an alkyl group having 1 to 4 carbon atoms which may have a substituent, an aryl group which may have a substituent, an acyl group,
A heterocyclic group or an unsaturated hydrocarbon group), a matrix formed by polycondensation with at least one metal alkoxide selected from the group consisting of: and a group X ₁ or X ₂ contained in the metal alkoxide A semiconductive polymer composition comprising a charge transporting substance having an affinity for a polymer. 3. The method according to claim 1, wherein the metal atom of the metal alkoxide is Al,
The semiconductive polymer composition according to claim 1 or 2, wherein the composition is selected from B, Ga, Y, Fe, si, Ge, Sn, Ti and Zi.