JP4813089B2 - Acrylic ester compound and acrylic ester compound mixture - Google Patents

Description

  The present invention relates to a novel acrylate compound useful as an organic semiconductor material used in organic electrophotographic photoreceptors, organic ELs, organic TFTs, organic solar cells and the like, and more particularly, charge transport function (hole transportability) in the molecule. ) Acrylic ester compound and acrylic having both a structural unit expressing) and an acrylic ester or methacrylic ester functional group and capable of forming a thermoplastic resin or crosslinked cured resin having a high crosslinking density by a chain reaction such as radical polymerization It relates to an acid ester compound mixture.

The organic semiconductor material having a charge transport function is useful as a semiconductor film forming material for organic devices such as an organic electrophotographic photoreceptor, organic EL, organic TFT, and organic solar battery. As a method for imparting such a charge transport function to a resin, a method in which a charge transport material is dispersed in a resin used as a binder in the formation of a functional film or the like is the most common. in use.
However, it is difficult to ensure the mechanical strength and heat resistance of the charge transporting functional film simply by mixing and dispersing the charge transporting material in the resin, and sufficient characteristics cannot be obtained. Therefore, in order to improve these characteristics, it is effective to combine and integrate the charge transporting material and the resin used as the binder.

For this reason, in recent years, efforts have been made to integrate a charge transporting material and a resin, and various charge transporting monomers in which a radical polymerizable group is bonded to a charge transporting structure and polymers thereof have been proposed.
For example, various charge transporting monomers having two or more chain polymerizable functional groups have been proposed, and application of these to electrophotographic photoreceptors has been proposed. Among the charge transporting monomers, in particular, acrylic ester compounds have good crosslinkability and many have been proposed (see, for example, Patent Documents 1, 2, 3, and 4). By using such a charge transporting monomer, it is said that precipitation resistance, abrasion resistance, scratch resistance, sensitivity, residual potential and the like are improved.

  In addition, the present applicant has previously proposed acrylic esters having an aromatic tertiary amine skeleton, polymers thereof, and electrophotographic photoreceptors (see, for example, Patent Documents 5, 6, and 7). By using these acrylates, the sensitivity and durability of the electrophotographic photoreceptor can be improved.

When focusing on the mobility of holes that exhibit charge transporting properties, it is known that aminobiphenyl structures and amino-substituted stilbene structures with expanded conjugated systems show higher mobility than simple triphenylamine structures, Of the above disclosed charge transporting monomers, those having these structures are particularly useful materials.
If such a charge transporting monomer is used for chain polymerization by radical polymerization or the like to form a three-dimensional cross-linked film having a sufficiently high cross-linking density, a film having high hardness and heat resistance can be obtained without being scratched. The durability can be improved when used in various organic semiconductor elements. However, there is a problem that by increasing the crosslink density, the charge transport property that is originally required is lowered and a sufficient function cannot be obtained.

  In other words, in the case of a large number of charge transporting monomers that have been proposed so far, the formation of a high crosslink density structure capable of meeting demands for durability and heat resistance against abrasion and scratches, etc., and at the same time, good charge transporting properties are exhibited. There is nothing that can be achieved in a compatible manner, and the development of a novel compound that can satisfy both has been desired.

JP 2000-66424 A JP 2000-66425 A JP 2000-206716 A JP 2004-221959 A Japanese Patent No. 3164426 Japanese Patent No. 3194392 Japanese Patent No. 3286704

The present invention has been made in view of the above prior art, and includes a structural unit having a charge transport function (hole transportability) in a molecule and a functional group having good chain polymerizability (for example, radical polymerizability). It has excellent compatibility with other monomers and film formability, and also has good charge transport properties along with the formation of a high-density cross-linked structure that can meet the requirements of mechanical durability such as wear and heat resistance by chain reaction. It is an object of the present invention to provide a novel acrylic ester compound and an acrylic ester compound mixture capable of achieving both of the above-mentioned expression.
The “acrylic ester compound” in the present invention is defined to refer to “a compound having an acrylic ester functional group and / or a methacrylic ester functional group”.

  As a result of intensive studies, the present inventors have introduced the above-mentioned problems by introducing an acrylate or methacrylate functional group into a hydroxy compound having a charge transport function comprising a stilbene structure in the molecule and an aromatic tertiary amine structure. The present inventors have found that an acrylic ester compound and an acrylic ester compound mixture can be obtained. Hereinafter, the present invention will be specifically described.

  The present invention is an acrylate compound represented by the following general formula (1).

(In the formula, Ra and Rb may be the same or different and each represents a hydrogen atom or a methyl group. Rc and Rd may be the same or different and each represents an alkyl group having 1 to 2 carbon atoms. Ar ₁ and Ar ₂ May be the same or different and each represents an aryl group having 6 to 16 carbon atoms, wherein the aryl group having 6 to 16 carbon atoms has one or two alkyl groups or methoxy groups having 1 to 2 carbon atoms I and j may be the same or different and each represents an integer of 0 to 2.)

  The present invention also provides the following general formula (1):

(In the formula, Ra and Rb may be the same or different and each represents a hydrogen atom or a methyl group. Rc and Rd may be the same or different and each represents an alkyl group having 1 to 2 carbon atoms. Ar ₁ and Ar ₂ May be the same or different and each represents an aryl group having 6 to 16 carbon atoms, wherein the aryl group having 6 to 16 carbon atoms has one or two alkyl groups or methoxy groups having 1 to 2 carbon atoms And may be substituted. I and j may be the same or different and each represents an integer of 0 to 2.)
The following general formula (2):

(In the formula, Ra, Rb, Rc, Rd, Ar ₁ , Ar ₂ and i, j are all synonymous with the above general formula (1)),
It is an acrylic ester compound mixture characterized by comprising.

  Moreover, this invention is an acrylate compound represented by following General formula (3).

(In the formula, Ra and Rb may be the same or different and each represents a hydrogen atom or a methyl group. Rc and Rd may be the same or different and each represents an alkyl group having 1 to 2 carbon atoms. Re and Rf are the same. Or may be different and represents an alkyl group having 1 to 2 carbon atoms or a methoxy group, and i, j, k, and l may be the same or different and represent an integer of 0 to 2 ).

  Furthermore, the present invention provides the following general formula (3):

(In the formula, Ra and Rb may be the same or different and each represents a hydrogen atom or a methyl group. Rc and Rd may be the same or different and each represents an alkyl group having 1 to 2 carbon atoms. Re and Rf are the same. Or may be different and represents an alkyl group having 1 to 2 carbon atoms or a methoxy group, i, j, k and l may be the same or different and each represents an integer of 0 to 2 ). A compound,
The following general formula (4):

(In the formula, Ra, Rb, Rc, Rd, Re, Rf and i, j, k, and l are all synonymous with the above general formula (3)) ,
It is an acrylic ester compound mixture characterized by comprising.

  And this invention is represented by following General formula (5), It is an acrylate compound characterized by the above-mentioned.

(Wherein, Rb is .Rc represents a hydrogen atom or a methyl group, Rd, which may be the same or different, represent. Ar _1, Ar ₂ an alkyl group having 1 or 2 carbon atoms, which may be the same or different, a carbon Represents an aryl group having 6 to 16 carbon atoms, wherein the aryl group having 6 to 16 carbon atoms may be substituted with one or two alkyl groups or methoxy groups having 1 to 2 carbon atoms ; j may be the same or different and represents an integer of 0 to 2.)

  The present invention also provides the following general formula (5):

(Wherein, Rb is .Rc represents a hydrogen atom or a methyl group, Rd, which may be the same or different, represent. Ar _1, Ar ₂ an alkyl group having 1 or 2 carbon atoms may be the same or different, a carbon Represents an aryl group having 6 to 16 carbon atoms, wherein the aryl group having 6 to 16 carbon atoms may be substituted with one or two alkyl groups or methoxy groups having 1 to 2 carbon atoms. May be the same or different and each represents an integer of 0 to 2.)
The following general formula (6):

(In the formula, Rb, Rc, Rd, Ar ₁ , Ar ₂ and i, j are all as defined in the general formula (5)),
The following general formula (7):

(In the formula, Rb, Rc, Rd, Ar ₁ , Ar ₂ and i, j are all as defined in the general formula (5)),
It is an acrylic ester compound mixture characterized by comprising.

  Moreover, this invention is an acrylate compound represented by following General formula (8).

(In the formula, Rb represents a hydrogen atom or a methyl group. Rc and Rd may be the same or different and each represents an alkyl group having 1 to 2 carbon atoms, and Re and Rf represent an alkyl group having 1 to 2 carbon atoms or a methoxy group. I, j, k, and l may be the same or different and each represents an integer of 0 to 2.)

  Furthermore, the present invention provides the following general formula (8):

(In the formula, Rb represents a hydrogen atom or a methyl group. Rc and Rd may be the same or different and each represents an alkyl group having 1 to 2 carbon atoms. Re and Rf are alkyl groups having 1 to 2 carbon atoms or A methoxy group, i, j, k and l may be the same or different and each represents an integer of 0 to 2 ).
The following general formula (9):

An acrylic ester compound represented by the formula (Rb, Rc, Rd, Re, Rf and i, j, k, l are all as defined in the general formula (8)):
The following general formula (10):

An acrylic ester compound represented by the formula (Rb, Rc, Rd, Re, Rf and i, j, k, l are all as defined in the general formula (8)):
It is an acrylic ester compound mixture characterized by comprising.

The acrylic ester compound or acrylic ester compound mixture of the present invention has charge transportability and chain polymerization properties such as radical polymerization, and is excellent in film forming properties and compatibility with other monomers. It can be easily polymerized by irradiation with ultraviolet rays, electron beams, radiation, etc. or use of a radical initiator to form a high-density cross-linked film, and also exhibits good charge transport properties while having a high-density cross-linked structure. Therefore, various organic semiconductor devices that require good charge transportability, mechanical durability, and heat resistance, such as the above-mentioned organic electrophotographic photosensitive member, organic EL, organic TFT, organic functional material for organic solar cells, etc. Can be used very effectively.
The acrylic ester compound or acrylic ester compound mixture of the present invention is obtained by subjecting a hydroxy compound having a triarylamine skeleton containing a stilbene structure in the molecule to ring-opening addition reaction of glycidyl acrylate (or glycidyl methacrylate) or epichlorohydrin. It can be easily obtained by introducing acid ester or methacrylate ester functional groups.

Details of the present invention will be described below.
The acrylic ester compound or acrylic ester compound mixture of the present invention is represented by any one of the general formulas (1) to (10).
R _a and R _b in the general formulas (1) to (4) represent a hydrogen atom or a methyl group, and may be the same or different. R _b in the general formulas (5) to (10) represents a hydrogen atom or a methyl group. A hydrogen atom and a methyl group are appropriately selected and used because of differences in chain polymerizability, for example, radical polymerizability, depending on the use environment.

In general formula (1), (2), (5), (6), (7) Ar 1, Ar 2 in is an aryl group which may have a location substituent, full Eniru group, a naphthyl group , Biphenylyl group, terphenylyl group, pyrenyl group, fluorenyl group, 9,9-dimethyl-2-fluorenyl group, azulenyl group, anthryl group, triphenylenyl group, chrysenyl group and the like, and represented by the following general formula (11) Examples of the representative compounds include the following Exemplified Compound Nos. 1-No. As seen in 40, it is preferably an aryl group having 6 to 16 carbon atoms.

[Wherein, R ₂₆ represents a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and X represents —O—, —S—, —SO—, —SO ₂ —, —CO— and a divalent group represented by the following general formulas (12) and (13) are represented.

(Here, R ₂₇ represents a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, a represents an integer of 1 to 12, and b represents an integer of 1 to 3.) ]

Examples of the substituent of the aryl group which may have a substituent and the substituent in R ₂₆ and R ₂₇ include a halogen atom, an optionally substituted alkyl group having 1 to 6 carbon atoms and a substituent. And an alkoxy group which may be used. Specific examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Specific examples of the alkyl group having 1 to 6 carbon atoms include methyl group, ethyl group, n-propyl group, i-propyl group, t-butyl group, s-butyl group, n-butyl group, i- Examples thereof include a butyl group, an n-pentyl group, an n-hexyl group, and a cyclohexyl group, and examples of the substituent include a halogen atom and a phenyl group . However, as typical substituents of the aryl group, the following Exemplified Compound Nos. 1-No. 40, it is preferable that it is a C1-C2 alkyl group or a methoxy group.

  Moreover, as the alkoxy group which may have a substituent, the alkoxy group which has the C1-C6 alkyl group which may have the said substituent is represented, and the alkoxy group which may have the substituent Specific examples thereof include methoxy group, ethoxy group, n-propoxy group, i-propoxy group, t-butoxy group, n-butoxy group, benzyloxy group and the like.

Rc and Rd in the general formulas (1), (2) and (5) to (7), and Rc, Rd, Re and Rf in the general formulas (3), (4) and (8) to (10) are Each represents an alkyl group having 1 to 6 carbon atoms which may have a substituent, an alkoxy group which may have a substituent, or an aryl group which may have a substituent. Rc, Rd, Re and Rf may be the same or different.
Specifically as a C1-C6 alkyl group which may have a substituent, a methyl group, an ethyl group, n-propyl group, i-propyl group, t-butyl group, s-butyl group, n -Butyl group, i-butyl group, n-pentyl group, n-hexyl group, cyclohexyl group and the like. Examples of the substituent include a halogen atom and a phenyl group. For example, specific examples of the alkyl group having 1 to 6 carbon atoms having a substituent include a trifluoromethyl group, a benzyl group, a 4-chlorobenzyl group, and a 4-methylbenzyl group.
Further, the alkoxy group represents an alkoxy group having an alkyl group having 1 to 6 carbon atoms which may have the above substituent, and specific examples thereof include a methoxy group, an ethoxy group, an n-propoxy group, and i-propoxy group. Group, t-butoxy group, n-butoxy group, benzyloxy group and the like.
Examples of the aryl group that may have a substituent include a phenyl group, a naphthyl group, a biphenylyl group, a terphenylyl group, a pyrenyl group, a fluorenyl group, a 9,9-dimethyl-2-fluorenyl group, an azulenyl group, an anthryl group, A triphenylenyl group, a chrycenyl group, etc. are mentioned. Examples of these substituents include halogen atoms and alkyl groups having 1 to 6 carbon atoms. The halogen atom and the alkyl group having 1 to 6 carbon atoms are the same as described above.
Specific examples of the halogen atom so far include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom .
However, the following Exemplified Compound Nos. 1-No. As seen from 40, typical examples of Rc and Rd are alkyl groups having 1 to 2 carbon atoms, and typical examples of Re and Rf are alkyl groups having 1 to 2 carbon atoms or methoxy groups.

  Specific examples of the acrylate compound of the present invention are represented by the following exemplified compound Nos. Represented by the case where Ra and Rb are hydrogen atoms in the general formula (1). 1-No. However, the present invention is not limited to these exemplary compounds, and Ra is a methyl group and Rb is a hydrogen atom, or Ra is a hydrogen atom and Rb is a methyl group, or Ra , Rb can be described similarly when both are methyl groups. Moreover, it can describe similarly about the similar structure body of the said General formula (1) represented by the said General formula (2). Of course, the same applies to the acrylate compounds represented by the general formulas (3) and (4).

Further, in the general formulas (5) to (10), the structure in which one acrylate group or methacrylic ester group is not introduced in the general formula (1) (which is an OH group or a CH ₂ OH group). The above-mentioned A, B, and D can be described similarly except being.

  The acrylic ester compound of the present invention is a novel substance. For example, a hydroxy compound is first synthesized by the procedure shown in the following reaction formula (a) (step A-1), and then as shown in the following reaction formula (b). The hydroxy compound obtained in step A-1 and glycidyl acrylate (or glycidyl methacrylate) are subjected to a ring-opening addition reaction to obtain a 2-hydroxypropyl methacrylate derivative (step A-2). The acrylic ester compound represented by the general formula (5) of the present invention is obtained.

In the ring-opening addition reaction (step A-2), an analogous structure of the general formula (5) represented by the following general formulas (6) and (7) is formed depending on the ring opening direction of the epoxy ring of glycidyl acrylate. By-product.
Therefore, in order to obtain the acrylate compound represented by the general formula (5), a separation operation is required. These separations are not always easy, and the yield is reduced by the separation operation. As a result of the study, the acrylate compound represented by the general formula (5) and the acrylate compound represented by the general formulas (6) and (7) can also be used as a mixture. Even if the mixture is used as it is, there is no effect on the properties, which is advantageous in terms of cost.

  Further, as shown in the following reaction formula (c), the 2-hydroxypropyl methacrylate derivative (acrylic ester compound represented by the general formula (5)) obtained above is reacted with acrylic acid chloride or methacrylic acid chloride. Thus, the acrylate compound represented by the general formula (1) can be easily synthesized (step A-3).

  Even if the step A-2 is changed to the step (B-1 step) shown by the following reaction formula (d), the 2-hydroxypropyl methacrylate derivative (the acrylate compound represented by the general formula (5) of the present invention) ) Can be easily synthesized.

In the case of B-1, an analogous structure of the general formula (5) represented by the following general formulas (6) and (7) is by-produced depending on the opening direction of the epoxy ring of epichlorohydrin.
Therefore, in order to obtain the acrylic ester compound represented by the general formula (5), a separation operation is necessary as described above, and the yield is reduced by the separation operation. As a result of the examination, there is no effect on the characteristics even if the acrylic ester compound represented by the general formula (5) and the acrylic ester compound represented by the general formulas (6) and (7) are used as a mixture. It is more cost effective to use it as a body.

  When the above mixture is used and the acrylate compound is synthesized by the step A-3, when Ra and Rb are different, an acrylate compound mixture is obtained.

  In addition, as shown in the following reaction formula (e), the epoxy compound or the 2-hydroxypropyl methacrylate derivative (the acrylic ester represented by the general formula (5) in the step B-1 (reaction formula (d)) Compound) hydrolyzate (dihydroxy compound) as a raw material, this raw material is reacted with acrylic acid chloride or methacrylic acid chloride (step C-1), and the acrylate compound represented by the general formula (1) (Rb = Ra) can be synthesized. That is, this synthesis method is easy to apply when Ra and Rb in the general formula (1) are the same.

  In addition, the methoxy compound (for example, 4-methoxy-4 ′-(di-p-tolylamino) stilbene) having a triarylamine skeleton having a triarylamine skeleton used in Step A-1 is dialkyl phosphonate (for example, 4-methoxy). Diethyl benzylphosphonate) or its derivatives and various benzaldehyde derivatives (eg 4- (di-p-tolylamino) benzaldehyde) can be synthesized in the presence of a metal alcoholate (eg tert-butoxypotassium).

In the acrylation process of the said A-3 process and C-1 process, it can synthesize | combine similarly to the esterification of the conventional hydroxy body. That is, (meth) acrylic acid or an ester compound thereof is reacted with an alcohol derivative. For example, an acrylate compound can be synthesized by heating and stirring an alcohol derivative and (meth) acrylic acid together with an esterification catalyst such as p-toluenesulfonic acid while dehydrating in an organic solvent. An acrylate compound can also be easily synthesized by reacting an alcohol derivative with acrylic acid chloride in an organic solvent in the presence of an alkali.
As the alkali, for example, an alkali aqueous solution such as sodium hydroxide or potassium hydroxide, or an amine base such as triethylamine or pyridine can be used. As the organic solvent, a hydrocarbon solvent such as toluene, an ether solvent such as tetrahydrofuran, an ester solvent such as ethyl acetate, or the like can be used.

  In the esterification in the step C-1, instead of using acrylic acid chloride, 3-chloropropanoic acid chloride is used, first a 3-chloropropanoic acid ester derivative is added, a base catalyst such as triethylamine is added, and the mixture is stirred with heating. An acrylic ester derivative can also be synthesized by dehydrochlorination. By using this method, it is possible to carry out acrylation in a high yield. A preferable solvent in this case is N, N-dimethylacetamide, and the reaction temperature is 0 to 100 ° C., preferably 10 to 80 ° C.

The acrylate compound of the present invention has an aromatic triarylamine structure in which a stilbene structural unit and an aryl group are bonded to each other in the molecule, and thus has a high hole mobility and a good charge transport function. As well as exerting an acrylic ester or methacrylic ester functional group, it exhibits good chain polymerizability, such as radical polymerizability. Therefore, it is possible to easily form a cured resin film having a high cross-linking density by irradiation with ultraviolet rays (UV), electron beams, radiations, etc. or use of a radical initiator, excellent film formability, and mechanical durability such as abrasion. It is possible to meet demands for heat resistance and heat, and at the same time, it is possible to exhibit good charge transport characteristics. Such excellent properties make it extremely useful as an organic functional material for various organic semiconductor devices such as organic electrophotographic photoreceptors, organic ELs, organic TFTs, and organic solar cells.
In addition, the acrylic ester compound of the present invention has good compatibility with other monomers. For example, methyl methacrylate, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, Tetrahydrofurfuryl acrylate, 2-ethylhexyl carbitol acrylate, 3-methoxybutyl acrylate, benzyl acrylate, cyclohexyl acrylate, isoamyl acrylate, isobutyl acrylate, methoxytriethylene glycol acrylate, phenoxytetraethylene glycol acrylate, cetyl acrylate, isostearyl acrylate, stearyl Acrylate, 1,3-butanediol diacrylate, 1,4-butanedio Diacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate, diethylene glycol diacrylate, neopentyl glycol diacrylate bisphenol A-EO modified diacrylate, bisphenol F- EO modified diacrylate, neopentyl glycol diacrylate, octafluoropentyl acrylate, 2-perfluorooctylethyl acrylate, 2-perfluorooctylethyl methacrylate, 2-perfluoroisononylethyl acrylate, acryloyl polydimethylsiloxane ethyl, methacryloyl polydimethyl Siloxane ethyl, acryloyl polydimethylsiloxane propyl, acryloyl polydimethyl Rusiloxane butyl, diacryloyl polydimethylsiloxane diethyl, trimethylolpropane triacrylate (TMPTA), trimethylolpropane trimethacrylate, trimethylolpropane alkylene-modified triacrylate, trimethylolpropane ethyleneoxy-modified (hereinafter EO-modified) triacrylate, trimethylol Propyleneoxy-modified (hereinafter PO-modified) triacrylate, trimethylolpropane caprolactone-modified triacrylate, trimethylolpropane alkylene-modified trimethacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate (PETTA), glycerol triacrylate, glycerol epichlorohydrin Modified (hereinafter ECH modified) Triacry Glycerol EO modified triacrylate, glycerol PO modified triacrylate, tris (acryloxyethyl) isocyanurate, dipentaerythritol hexaacrylate (DPHA), dipentaerythritol caprolactone modified hexaacrylate, dipentaerythritol hydroxypentaacrylate, alkylation Dipentaerythritol pentaacrylate, alkylated dipentaerythritol tetraacrylate, alkylated dipentaerythritol triacrylate, dimethylolpropane tetraacrylate (DTMPTA), pentaerythritol ethoxytetraacrylate, phosphoric acid EO modified triacrylate, 2, 2, 5, 5, -tetrahydroxymethylcyclopentanone tetraacrylate And the like.
These other monomers may be used singly or in combination and mixed with the acrylate compound of the present invention, and can be selected according to the desired required characteristics. The mixing amount of these other monomers varies depending on the purpose. For example, when applied to the charge transport layer of an electrophotographic photoreceptor, the mixing ratio (wt%) with the acrylate compound of the present invention is usually 1 to 80%, Preferably it is 10 to 70%, more preferably 30 to 70%.
The acrylic ester compound of the present invention can be used by mixing with the other monomers described above, and is excellent in film formability while maintaining the surface smoothness after curing. If the curing speed is slow and curing does not progress uniformly, even if a good film is formed during coating before curing, unevenness occurs in the film due to distortion due to curing shrinkage during curing, resulting in a coating defect The acrylate compound of the present invention has a high reaction site mobility, and since it is bifunctionalized, it is considered that polymerization proceeds rapidly over the entire film and coating defects are unlikely to occur.

  EXAMPLES Hereinafter, although a synthesis example and an evaluation example are given and this invention is demonstrated further in detail, this invention is not limited to these Examples.

(Example 1)
Synthesis of diethyl 4-methoxybenzylphosphonate, synthesis of 4-methoxy-4 ′-(di-p-tolylamino) stilbene, synthesis of 4-hydroxy-4 ′-(di-p-tolylamino) stilbene by the following procedure Using this, 2-hydroxy-3- [4 ′-(di-p-tolylamino) stilben-4-yloxy] propyl methacrylate [acrylic acid ester compounds represented by general formulas (5) and (8)] Is equivalent to the desired 2-acryloyloxy-3- [4 ′-(di-p-tolylamino) stilben-4-yloxy] propyl methacrylate [represented by the general formulas (1) and (3)] Equivalent to an acrylic ester compound] was synthesized.

[Synthesis of diethyl 4-methoxybenzylphosphonate]
4-Methoxybenzyl chloride and triethyl phosphite were reacted at 150 ° C. for 5 hours. Thereafter, excess triethyl phosphite and by-product ethyl chloride were removed by distillation under reduced pressure to obtain diethyl 4-methoxybenzylphosphonate.

[Synthesis of 4-methoxy-4 ′-(di-p-tolylamino) stilbene]
Equimolar diethyl 4-methoxybenzylphosphonate and 4- (di-p-tolylamino) benzaldehyde were dissolved in N, N-dimethylformamide, and tert-butoxypotassium was added little by little with stirring under water cooling. After stirring at room temperature for 5 hours, water was added to make it acidic, and a crude product of the desired product was obtained. Further, purification was performed by column chromatography on silica gel to obtain the desired 4-methoxy-4 ′-(di-p-tolylamino) stilbene.

[Synthesis of 4-hydroxy-4 ′-(di-p-tolylamino) stilbene]
4-Methoxy-4 ′-(di-p-tolylamino) stilbene and 2 equivalents of sodium ethanethiolate were dissolved in N, N-dimethylformamide and reacted at 130 ° C. for 5 hours. Thereafter, the mixture was cooled and poured into water, neutralized with hydrochloric acid, and the target product was extracted with ethyl acetate. The extract was washed with water, dried and evaporated to give a crude product. Furthermore, it refine | purified by the column chromatography with a silica gel, and obtained the target 4-hydroxy-4'- (di-p-tolylamino) stilbene.

[Synthesis of 2-hydroxy-3- [4 ′-(di-p-tolylamino) stilben-4-yloxy] propyl methacrylate]
In a reaction vessel equipped with a stirrer, thermometer, condenser, and dropping funnel, 6.4 g of 4-hydroxy-4 ′-(di-p-tolylamino) stilbene, 1.8 g of benzyltriethylammonium chloride, and 40 ml of tetrahydrofuran were added. A solution of 3.3 ml of glycidyl methacrylate / 10 ml of tetrahydrofuran was added dropwise at room temperature under a nitrogen stream. Then, it heated and refluxed for 40 hours.
After completion of the reaction, the reaction mixture was diluted with ethyl acetate, passed through silica gel, and the solvent was distilled off to obtain 8.5 g of a crude product. Further, the residue was purified by column chromatography using silica gel (solvent: hexane / ethyl acetate (2/1)) to give 2-hydroxy-3- [4 ′-(di-p-tolylamino) stilben-4-yloxy] propyl. Methacrylate was obtained (yield 1.0 g, yellow syrup). An infrared absorption spectrum of the obtained target product is shown in FIG. As a result of mass analysis of this synthetic substance, the mass per unit charge obtained by ionization by the atmospheric pressure chemical ionization method was m / z = 534, which coincided with the value of molecular weight + 1 (proton addition). .

  It should be noted that 2-hydroxy-3- [4 ′-(di-p-tolylamino) stilben-4-yloxy] propyl methacrylate and its structural analog (reaction byproduct) 2-hydroxymethyl- A mixture with 2- [4 ′-(di-p-tolylamino) stilben-4-yloxy] ethyl methacrylate was obtained (yield: 3.0 g, yellow syrup).

[Synthesis of 2-acryloyloxy-3- [4 ′-(di-p-tolylamino) stilben-4-yloxy] propyl methacrylate]
In a reaction vessel equipped with a stirrer, a thermometer, and a dropping funnel, 5.4 g of 2-hydroxy-3- [4 ′-(di-p-tolylamino) stilben-4-yloxy] propyl methacrylate, 50 ml of tetrahydrofuran, and 2 g of triethylamine were added. Then, a mixed solution of 1.9 g of acryloyl chloride and 5 ml of tetrahydrofuran was added dropwise at 15 ° C. under a nitrogen stream. Then, it was made to react at room temperature for 5 hours. After completion of the reaction, the mixture was diluted with 100 ml of toluene and washed with water to obtain an organic layer. The concentrated solution was purified by column chromatography using silica gel (solvent: hexane / ethyl acetate (3/1)) and 2-acryloyloxy-3- [4′- represented by the following structural formula (1-1). (Di-p-tolylamino) stilben-4-yloxy] propyl methacrylate was obtained (yield 3.2 g, yellow oil). An infrared absorption spectrum of the obtained target product is shown in FIG. As a result of mass analysis of this synthetic substance, the mass per unit charge obtained by ionization by the atmospheric pressure chemical ionization method was m / z = 588, which coincided with the value of molecular weight + 1 (proton addition). .

(Example 2)
[2-acryloyloxy-3- [4 ′-(di-p-tolylamino) stilben-4-yloxy] propyl methacrylate and 2-acryloyloxymethyl-2- [4 ′-(di-p-tolylamino) stilbene-4 -Synthesis of mixtures with yloxy] ethyl methacrylate
2-Hydroxy-3- [4 ′-(di-p-tolylamino) stilben-4-yloxy] propyl methacrylate obtained in Example 1 above and 2-hydroxymethyl-2- [4 which is a structural analog thereof Using 3 g of a mixture with '-(di-p-tolylamino) stilben-4-yloxy] ethyl methacrylate, the synthesis was carried out in the same manner as in the synthesis conditions of the acrylate compound in Example 1, and the desired acrylate compound mixture Body was obtained (yield 2.75 g, yellow oil).
The acrylic ester compound mixture thus obtained has the same characteristics as in the case of 2-acryloyloxy-3- [4 ′-(di-p-tolylamino) stilben-4-yloxy] propyl methacrylate alone. Therefore, it is advantageous in terms of cost to use it as a mixture without a precise separation operation.

(Example 3)
1,2-Dihydroxy-3- [4 ′-(di-p-tolylamino) stilben-4-yloxy] propane shown below is synthesized, and then 2-acryloyloxy-3- [4 ′-( Di-p-tolylamino) stilben-4-yloxy] propyl acrylate (corresponding to Exemplified Compound No. 2) was synthesized.

[Synthesis of 1,2-dihydroxy-3- [4 ′-(di-p-tolylamino) stilben-4-yloxy] propane]
A reaction vessel equipped with a stirrer, thermometer, condenser, and dropping funnel was charged with 11.75 g of 4-hydroxy-4 ′-(di-p-tolylamino) stilbene, 4.35 g of glycidyl methacrylate, and 8 ml of toluene. Then, 0.16 g of triethylamine was added, and the mixture was heated and stirred at 95 ° C. for 8 hours. Thereafter, 16 ml of toluene and 20 ml of a 10% aqueous sodium hydroxide solution were added, and the mixture was further heated and stirred at 95 ° C. for 8 hours. After completion of the reaction, the reaction mixture was diluted with ethyl acetate, washed with acid and washed with water, and then the solvent was distilled off to obtain 19 g of a crude product. Further, the residue was purified by column chromatography using silica gel (solvent: ethyl acetate), and 1,2-dihydroxy-3- [4 ′-(di-p-tolylamino) stilbene-- of the following structural formula (1-2) 4-yloxy] propane was obtained (yield 9.85 g, yellow crystals, melting point 127-128.7 ° C., infrared absorption spectrum is shown in FIG. 3). The mass per unit charge obtained by ionization by the ionization method was m / z = 466, which coincided with the value of molecular weight + 1 (proton addition).

[Synthesis of 2-acryloyloxy-3- [4 ′-(di-p-tolylamino) stilben-4-yloxy] propyl acrylate (corresponding to Exemplified Compound No. 2)]
In a reaction vessel equipped with a stirrer, a thermometer, and a dropping funnel, 1.0 g of 1,2-dihydroxy-3- [4 ′-(di-p-tolylamino) stilben-4-yloxy] propane, N, N-dimethyl 10 ml of acetamide was added, and 1.09 g of 3-chloropropanoic acid chloride was added dropwise at 3 ° C. under a nitrogen stream. Then, it was made to react at room temperature for 8 hours. Next, 1.74 g of triethylamine was added, and the mixture was further reacted at 60 ° C. for 4 hours. After completion, the mixture was extracted with methylene chloride and washed with water to obtain an organic layer. The concentrated solution was purified by column chromatography using silica gel (solvent: hexane / ethyl acetate (2/1)) to obtain the desired product. (Yield 1.1 g, yellow oil, infrared absorption spectrum is shown in FIG. 4) As a result of mass analysis of this synthetic substance, the mass per unit charge obtained by ionization by the atmospheric pressure chemical ionization method was positive. M / z = 574, which coincided with the value of molecular weight + 1 (proton addition).

[Evaluation Example 1]
<Elution amount from cured film>
The acrylic ester compound of structural formula (1-1) synthesized in Example 1 above, the acrylic ester compound mixture synthesized in Example 2, and 2-acryloyloxy-3- [4′- synthesized in Example 3 Using (di-p-tolylamino) stilben-4-yloxy] propyl acrylate (corresponding to Exemplified Compound No. 2) and the following comparative compounds (I) [Ref-1] to (VII) [Ref-7] The following coating liquid (A) to coating liquid (J) are prepared, and 10 types of these coating liquids are blade coated on an aluminum plate and dried by touching, and then irradiated with ultraviolet rays under the following conditions. A cured film having a thickness of 5 μm was prepared. The obtained cured film was immersed in tetrahydrofuran for 7 days, and the elution amount from the cured film was measured. The evaluation results are shown in Table 1 below.
Hereinafter, “part” means “part by weight”.

<Coating fluid A>
Acrylic ester compound of Example 1 [Structural Formula (1-1)]: 10 parts Trimethylolpropane triacrylate: 10 parts Polymerization initiator (1-hydroxycyclohexyl phenyl ketone): 1 part Tetrahydrofuran: 84 parts

<Coating fluid B>
In place of the acrylic ester compound of structural formula (1-1) used in coating liquid A, the same composition as in coating liquid A was used except that the acrylic ester compound mixture obtained in Example 2 was used. A coating solution B was prepared.

<Coating fluid C>
In place of the acrylic ester compound of the structural formula (1-1) used in the coating liquid A, the exemplified compound No. 1 obtained in Example 3 was used. A coating liquid C was prepared with the same composition as the coating liquid A except that the acrylic acid ester compound 2 was used.

<Coating fluid D>
The same composition as the coating liquid A except that the following compound (I) [Ref-1] is used as a comparative compound in place of the acrylic ester compound of the structural formula (1-1) used in the coating liquid A. A coating solution D was prepared.

<Coating fluid E>
The same composition as the coating liquid A except that the following compound (II) [Ref-2] is used as a comparative compound instead of the acrylic ester compound of the structural formula (1-1) used in the coating liquid A. A coating solution E was prepared.

<Coating fluid F>
The same composition as the coating liquid A except that the following compound (III) [Ref-3] is used as a comparative compound in place of the acrylic ester compound of the structural formula (1-1) used in the coating liquid A. A coating solution F was prepared.

<Coating fluid G>
The same composition as the coating liquid A except that the following compound (IV) [Ref-4] is used as a comparative compound in place of the acrylic ester compound of the structural formula (1-1) used in the coating liquid A. A coating solution G was prepared.

<Coating fluid H>
The same composition as the coating liquid A except that the following compound (V) [Ref-5] is used as a comparative compound in place of the acrylic ester compound of the structural formula (1-1) used in the coating liquid A. A coating solution H was prepared.

<Coating fluid I>
The same composition as the coating liquid A except that the following compound (VI) [Ref-6] is used as a comparative compound in place of the acrylic ester compound of the structural formula (1-1) used in the coating liquid A. A coating solution I was prepared.

<Coating fluid J>
The same composition as the coating liquid A except that the following compound (VII) [Ref-7] is used as a comparative compound in place of the acrylic ester compound of the structural formula (1-1) used in the coating liquid A. A coating solution J was prepared.

<Ultraviolet irradiation conditions for cured film formation>
Lamp: Metal halide lamp 160W / cm
Irradiation distance: 120mm
Irradiation intensity: 500 mW / cm ²
Irradiation time: 60 seconds

  From the above evaluation results, the acrylate compound or the acrylate compound mixture of the present invention has a smaller elution amount than the conventionally known charge transporting monomers shown in the comparative examples, and has a high crosslinking density by chain polymerization. It can be seen that a cured film is formed. Such a high-density crosslinked structure can meet the improvement in mechanical durability and heat resistance against wear and scratches required when applied as an organic functional material for various organic semiconductor devices.

[Evaluation Example 2]
<Evaluation of charge transportability>
By coating and drying an undercoat layer coating solution, a charge generation layer coating solution, and a charge transport layer coating solution in the following order on an aluminum plate in sequence, an undercoat layer of 0.3 μm; Ten types of photoconductors (1) to (10) were prepared by forming a 3 μm charge generation layer and a 20 μm charge transport layer. In the case of the charge transport layer coating solution, a crosslinked structure was formed by chain polymerization after coating and drying.
In addition, the acrylics of the structural formula (1-1) of the present invention synthesized in Examples 1 to 3, respectively, as the components of the following charge transport layer coating solutions (1) to (10) in 10 types of photoreceptors. Acid ester compound, acrylic ester compound mixture synthesized in Example 2, and Exemplified Compound No. 1 synthesized in Example 3. 2 acrylic acid ester compounds and the respective acrylic compounds of comparative compounds (I) [Ref-1] to (VII) [Ref-7] used in the above-described evaluation of curability were used.

<Coating liquid for undercoat layer>
Polyamide resin (CM-8000: manufactured by Toray Industries, Inc.): 2 parts Methanol: 49 parts Butanol: 49 parts

<Coating liquid for charge generation layer>
Bisazo pigment of the following structural formula (VIII): 2.5 parts Polyvinyl butyral (XYHL: manufactured by UCC): 0.5 parts Cyclohexanone: 200 parts Methyl ethyl ketone: 80 parts

<Coating liquid for charge transport layer: (1) to (10)>
Bisphenol Z polycarbonate
(Panlite TS-2050, manufactured by Teijin Kasei Co., Ltd.): 10 parts Charge transporting monomer (acrylic ester compound shown in Table 2): 10 parts Tetrahydrofuran: 80 parts Tetrahydrofuran solution of 1% silicone oil
(KF-50-100CS, manufactured by Shin-Etsu Chemical Co., Ltd.): 0.2 part

With respect to the photoreceptors (1) to (10) obtained as described above, a commercially available electrostatic copying paper test apparatus [EPA-8200 type manufactured by Kawaguchi Electric Mfg. Co., Ltd.] was used to charge transport from half-exposure amount and residual potential. Evaluated.
That is, after charging to −800 V by −6 kV corona discharge in a dark place, tungsten lamp light is irradiated so that the illuminance on the surface of the photosensitive member becomes 4.5 lux, and the potential is reduced to ½. The time (second) was obtained, and the half-exposure amount E1 / 2 (lux · sec) was calculated. Further, the residual potential (−V) after 30 seconds of exposure was determined. The smaller the half-exposure amount, the better the sensitivity, and the smaller the residual potential, the fewer charge traps.
The evaluation results are shown in Table 2 below.

  From the above evaluation results, the photoconductors (1) to (3) using the acrylate compound of the present invention are half-exposure compared to the comparative photoconductors (4) to (10) using the conventional acrylic compound. It is clear that the amount is small, the sensitivity is good, there is no residual potential and there is no charge trapping, and good charge transport properties are exhibited.

From the above evaluation example 1 (elution amount from the cured film) and evaluation example 2 (charge transportability evaluation), the formation of a high-density cross-linked structure capable of dealing with mechanical durability and heat resistance by a chain reaction and good charge It is the acrylic ester compound of the present invention that can exhibit both transport properties, and none of the conventionally known charge transporting monomers can achieve compatibility.
Therefore, the acrylic ester compound of the present invention is extremely effective as a material for providing the various organic semiconductor devices.

2 is an infrared absorption spectrum diagram of 2-hydroxy-3- [4 ′-(di-p-tolylamino) stilben-4-yloxy] propyl methacrylate synthesized in Example 1. FIG. 2 is an infrared absorption spectrum diagram of 2-acryloyloxy-3- [4 ′-(di-p-tolylamino) stilben-4-yloxy] propyl methacrylate synthesized in Example 1. FIG. 4 is an infrared absorption spectrum diagram of 1,2-dihydroxy-3- [4 ′-(di-p-tolylamino) stilben-4-yloxy] propane synthesized in Example 3. FIG. 4 is an infrared absorption spectrum diagram of 2-acryloyloxy-3- [4 ′-(di-p-tolylamino) stilben-4-yloxy] propyl acrylate synthesized in Example 3. FIG.

Claims (8)

An acrylate compound represented by the following general formula (1):

(In the formula, Ra and Rb may be the same or different and each represents a hydrogen atom or a methyl group. Rc and Rd may be the same or different and each represents an alkyl group having 1 to 2 carbon atoms. Ar ₁ and Ar ₂ May be the same or different and each represents an aryl group having 6 to 16 carbon atoms, wherein the aryl group having 6 to 16 carbon atoms has one or two alkyl groups or methoxy groups having 1 to 2 carbon atoms I and j may be the same or different and each represents an integer of 0 to 2.) The following general formula (1):

(In the formula, Ra and Rb may be the same or different and each represents a hydrogen atom or a methyl group. Rc and Rd may be the same or different and each represents an alkyl group having 1 to 2 carbon atoms. Ar ₁ and Ar ₂ May be the same or different and each represents an aryl group having 6 to 16 carbon atoms, wherein the aryl group having 6 to 16 carbon atoms has one or two alkyl groups or methoxy groups having 1 to 2 carbon atoms And may be substituted. I and j may be the same or different and each represents an integer of 0 to 2.)
The following general formula (2):

(In the formula, Ra, Rb, Rc, Rd, Ar ₁ , Ar ₂ and i, j are all synonymous with the above general formula (1)),
An acrylic ester compound mixture comprising: An acrylate compound represented by the following general formula (3):

(In the formula, Ra and Rb may be the same or different and each represents a hydrogen atom or a methyl group. Rc and Rd may be the same or different and each represents an alkyl group having 1 to 2 carbon atoms. Re and Rf are the same. Or may be different and represents an alkyl group having 1 to 2 carbon atoms or a methoxy group, and i, j, k, and l may be the same or different and represent an integer of 0 to 2 ). The following general formula (3):

(In the formula, Ra and Rb may be the same or different and each represents a hydrogen atom or a methyl group. Rc and Rd may be the same or different and each represents an alkyl group having 1 to 2 carbon atoms. Re and Rf are the same. Or may be different and represents an alkyl group having 1 to 2 carbon atoms or a methoxy group, i, j, k and l may be the same or different and each represents an integer of 0 to 2 ). A compound,
The following general formula (4):

(In the formula, Ra, Rb, Rc, Rd, Re, Rf and i, j, k, and l are all synonymous with the above general formula (3)) ,
An acrylic ester compound mixture comprising: An acrylate compound represented by the following general formula (5):

(Wherein, Rb is .Rc represents a hydrogen atom or a methyl group, Rd, which may be the same or different, represent. Ar _1, Ar ₂ an alkyl group having 1 or 2 carbon atoms may be the same or different, a carbon Represents an aryl group having 6 to 16 carbon atoms, wherein the aryl group having 6 to 16 carbon atoms may be substituted with one or two alkyl groups or methoxy groups having 1 to 2 carbon atoms ; j may be the same or different and represents an integer of 0 to 2.) The following general formula (5):

(Wherein, Rb is .Rc represents a hydrogen atom or a methyl group, Rd, which may be the same or different, represent. Ar _1, Ar ₂ an alkyl group having 1 or 2 carbon atoms may be the same or different, a carbon Represents an aryl group having 6 to 16 carbon atoms, wherein the aryl group having 6 to 16 carbon atoms may be substituted with one or two alkyl groups or methoxy groups having 1 to 2 carbon atoms. May be the same or different and each represents an integer of 0 to 2.)
The following general formula (6):

(In the formula, Rb, Rc, Rd, Ar ₁ , Ar ₂ and i, j are all as defined in the general formula (5)),
The following general formula (7):

(In the formula, Rb, Rc, Rd, Ar ₁ , Ar ₂ and i, j are all as defined in the general formula (5)),
An acrylic ester compound mixture comprising: An acrylate compound represented by the following general formula (8):

(In the formula, Rb represents a hydrogen atom or a methyl group. Rc and Rd may be the same or different and each represents an alkyl group having 1 to 2 carbon atoms, and Re and Rf represent an alkyl group having 1 to 2 carbon atoms or a methoxy group. I, j, k, and l may be the same or different and each represents an integer of 0 to 2.) The following general formula (8):

(In the formula, Rb represents a hydrogen atom or a methyl group. Rc and Rd may be the same or different and each represents an alkyl group having 1 to 2 carbon atoms. Re and Rf are alkyl groups having 1 to 2 carbon atoms or A methoxy group, i, j, k and l may be the same or different and each represents an integer of 0 to 2 ).
The following general formula (9):

An acrylic ester compound represented by the formula (Rb, Rc, Rd, Re, Rf and i, j, k, l are all as defined in the general formula (8)):
The following general formula (10):

An acrylic ester compound represented by the formula (Rb, Rc, Rd, Re, Rf and i, j, k, l are all as defined in the general formula (8)):
An acrylic ester compound mixture comprising:

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