JPH0583086B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to a method for producing a novel thin film polymer. More specifically, the present invention relates to a method for easily producing a thin film polymer useful as a crosslinking agent, a photosensitive material, an electronic device material, an electron beam resist material in microphosphorography, and the like. Conventional technology Due to its molecular structure, 5,5'-(1,4-phenylene)-bis(2-cyano-2,4-pentadienoic acid) dialkyl ester can be produced into a thin film-like polymer. If possible, it can be used as a material for various functional materials. However, this polymer is polymerized by light in a crystalline state to produce a crystalline polymer, but this polymer is difficult to process and form into a thin film, and is usually handled as a crystal or powder. Therefore, it has been difficult to use it in electronic devices. Incidentally, the Langmuir-Blodget method is known as a method for preparing a thin film having a certain molecular arrangement and a certain thickness on the order of angstroms. When preparing a thin film using this method, it is necessary to use a compound having a chemical structure capable of forming a monomolecular film, that is, an amphiphilic compound having a hydrophilic group and a hydrophobic group in the molecule. Therefore, in order to produce thin film-like polymers with excellent mechanical strength that can be used in electronic devices, etc., by using the Langmuir-Blodget method, it is necessary to use amphiphilic compounds having polymerizable functional groups. What is necessary is to produce a membrane and polymerize it. However, it is not always easy to synthesize amphiphilic compounds having polymerizable functional groups, and depending on the chemical structure of the compound, a monomolecular film is not necessarily formed. Problems to be Solved by the Invention The present invention is directed to 5,5'-(1,4-phenylene)-bis(2), which is a photoreactive compound that is relatively easy to synthesize.
The present invention provides a method for easily producing a thin film polymer using dialkyl (cyano-2,4-pentadienoic acid) ester. Means for Solving the Problems As a result of intensive research to develop a method for easily producing a thin film polymer of the dialkyl ester, the present inventors found that the dialkyl ester is If the group has a large number of carbon atoms, it will itself form a monolayer, whereas if the alkyl group has a small number of carbon atoms, it is possible to form a monolayer by mixing it with an appropriate amphipathic compound. The monomolecular film of can be accumulated on a substrate such as a quartz plate and has photopolymerizability, so
The inventors have discovered that a thin film polymer can be easily obtained by irradiating this cumulative film with light, and have completed the present invention based on this knowledge. That is, the present invention provides the general formula

5,5'-(1,4-phenylene)-bis(2-cyano-2,4-pentadieno The present invention provides a method for producing a thin film polymer, which comprises preparing a cumulative film made of a dialkyl ester of succinic acid or a mixture of this and an amphipathic compound, and then irradiating the film with light. The present invention will be explained in detail below. 5,5′- used as a monomer in the present invention
(1,4-phenylene)-bis(2-cyano-2,
The (4-pentadienoic acid) dialkyl ester has a structure represented by the general formula (), in which R is a saturated alkyl group having 5 to 20 carbon atoms. Although this substance has a hydrophobic group in its molecule, it was thought that it would not form a monomolecular film because it does not have a strong hydrophilic group. 2-cyano-2,4-pentadienoic acid) di-n-dodecyl ester forms a monomolecular film by itself. In addition, 5,5'-(1,4-phenylene)-bis(2-cyano-2,4-pentadienoic acid) dialkyl ester, which has a small number of carbon atoms in the alkyl group, can be mixed with an appropriate amphipathic compound. By doing so, a stable monomolecular film is formed on the surface of water or a liquid such as a cadmium chloride aqueous solution. The formation of such a monomolecular film is evident from the confirmation of the presence of a solid condensed phase in the surface pressure-occupied area curve. The amphiphilic compound as used in the present invention is a compound that has both a hydrophilic group and a hydrophobic group in its molecule, and such compounds usually have an alkyl group with 12 carbon atoms.
~20 long chain saturated fatty acids and long chain saturated alcohols are used. Examples of long-chain saturated fatty acids include tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, stearic acid, nonadecanoic acid, and arachidic acid. Examples of long-chain saturated alcohols include lauryl alcohol, tridecyl alcohol, myristyl alcohol, pentadecyl alcohol, cetyl alcohol, heptadecyl alcohol, stearyl alcohol, nonadecyl alcohol, and eicosyl alcohol. These amphiphilic compounds may be used alone or in combination of two or more. Next, one example of a suitable method for preparing the cumulative film will be explained. The ester alone or this and a suitable amphipathic compound are usually mixed in a molar ratio of 1:
After dissolving in an organic solvent such as chloroform at a ratio of 5 to 1:1, this solution is gradually dropped onto the surface of a liquid such as distilled water or an aqueous cadmium chloride solution.
5,5′-(1,4-phenylene)-bis(2-cyano-2,4-pentadienoic acid) dialkyl ester, or this and an amphiphilic compound, are compressed and placed on the liquid surface. A cumulative film is created by repeating the steps of forming a monomolecular film consisting of a mixture of the above and then transferring this monomolecular film onto a substrate such as a quartz plate. The absorption spectrum of the cumulative film created in this way has an absorption maximum at 360 nm, which is different from that of a crystal or solution (absorption maximum of 400 nm).
It can be seen that the cumulative film has a molecular arrangement different from that of crystals or solutions. When the cumulative film thus produced is irradiated with light using a xenon lamp or the like, addition polymerization easily occurs and a thin film-like polymer is obtained. For example, when a 10-layer film is irradiated with light of 420 nm or more, the absorbance in the ultraviolet absorption spectrum gradually decreases, while in the infrared absorption spectrum, the absorption of double bonds (1610 cm ^-1 ) decreases and It can be seen that a reaction occurred between the heavy bonds. The thin film obtained by such light irradiation is soluble in tetrahydrofuran, and has a molecular weight of about 1000 to 300 as measured by gel permeation chromatography. from these things,
It can be seen that the thin film is a dimer to pentamer low polymer having a cyclobutane ring produced by a cycloaddition reaction of double bonds. In this low polymer thin film,
When irradiated with light of 320 nm or more, the absorbance decreases,
The absorption maximum at 360 nm almost disappears. This is thought to be because the double bond reaction progresses further and becomes a high polymer, and the resulting thin film becomes difficult to dissolve in common organic solvents. This high polymer film is 290nm
When irradiated with the following light, depolymerization occurs and becomes a low polymer, and when this low polymer is irradiated with light of 320 nm or more, it becomes a high molecular weight polymer again. This indicates that the thin film polymer produced by the production method of the present invention has reversible depolymerizability by light. Since the thin film polymer has such properties and high mechanical strength, it can be used as a resist material in the production of electronic devices and microlithography. Effects of the Invention According to the method of the present invention, 5,5'-(1,4-phenylene)-bis(2-cyano-2,4-pentadienoic acid) dialkyl ester is used as a monomer, and the cumulative film is By irradiating with light, a thin film-like polymer can be easily produced. The thin film polymer obtained by the method of the present invention is reversibly depolymerizable by light and has good mechanical strength, so it can be used, for example, in the production of electronic devices, as a resist material in microlithography, or as a crosslinking agent. It is useful as a photosensitive material. Examples Next, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples in any way. Example 1 5, purified by several recrystallizations from acetone
5'-(1,4-phenylene)-bis(2-cyano-
Chloroform solution of di-n-dodecyl ester (2,4-pentadienoitsuccinic acid) (0.89×10 ^-3 M)
was gradually dropped onto the surface of an aqueous cadmium chloride solution (10 ^-3 M), expanded, and then compressed to form a monomolecular film. The presence of a solid condensed phase was confirmed from the surface pressure-occupied area curve at 20 to 30 dyn/cm, so the surface pressure was
A monomolecular film was formed by setting at 25 dyn/cm.
Next, the monomolecular film thus formed was transferred to a quartz plate by a vertical dipping method to produce a cumulative film consisting of 10 monomolecular film layers. This cumulative film is 360nm
It has an absorption ^maximum at It was shown that the reaction occurred between double bonds. A film irradiated with light for 15 minutes is almost insoluble in common organic solvents, but a film irradiated for a short time, for example 1 minute, is soluble in tetrahydrofuran, and the molecular weight determined by gel permeation chromatography is 1200~ 3000 (2~
pentamer). Example 2 5,5'- purified by recrystallization from acetone
(1,4-phenylene)-bis(2-cyano-2,
A chloroform solution of di-n-hexyl ester (4-pentadienoitsuccinic acid) (0.89 x 10 ^-3 M) and a chloroform solution of arachidic acid (0.89 x 10 ^-3 M) were mixed at a molar ratio of 1:5. This solution was gradually dropped onto the surface of a cadmium chloride aqueous solution (10 ^-3 M) and developed, and the surface pressure-occupied area curve was measured. The presence of a solid condensed phase was observed in this curve, confirming the formation of a monomolecular film. Therefore, the surface pressure
A monomolecular film was formed by setting at 25 dyn/cm. Next, the monomolecular film thus formed was transferred onto a quartz plate by a vertical dipping method to produce a cumulative film consisting of 10 monomolecular film layers. The absorption spectrum of this cumulative film has an absorption maximum at 360 nm, and when it is irradiated with light of 420 nm or more using a xenon lamp as a light source and a filter (Corning 3-72),
The absorbance gradually decreases, but there is an absorption maximum at 860 nm. The accumulated film after irradiation for 3 minutes was dissolved in tetrahydrofuran, and the molecular weight was examined by gel permeation chromatography, and it was found to be a dimer to pentamer. In addition to this low polymer
When irradiated with light above 320 nm, the absorption maximum decreased and almost disappeared. This membrane is insoluble in common organic solvents and is a high polymer. When this high polymer was irradiated with short wavelength light (λ < 290 nm), an absorption maximum at 360 nm gradually appeared, indicating depolymerization to a low polymer. When this low polymer is irradiated with light of 320 nm or more, it becomes a high polymer again, and the conversion from high polymer to low polymer proceeds reversibly by light. Example 3 5,5'- purified by recrystallization from acetone
(1,4-phenylene)-bis(2-cyano-2,
A chloroform solution of di-n-dodecyl ester (4-pentadienoitsuccinic acid) (0.89 x 10 ^-3 M) and a chloroform solution of arachidic acid (0.89 x 10 ^-3 M) were mixed at a molar ratio of 1:2. A fixed amount of this solution was dropped onto the surface of distilled water, developed, and then gradually compressed to measure the surface pressure-occupied area curve.
The presence of a solid condensed phase was observed in this curve, confirming the formation of a monomolecular film. Therefore, the surface pressure was set to 30dyn/cm.
was set to form a monomolecular film. Next, the monomolecular film thus formed was transferred onto a quartz plate by a vertical dipping method to produce a cumulative film consisting of 10 monomolecular film layers. The absorption spectrum of this cumulative film has an absorption maximum at 360 nm, and a xenon lamp is used as a light source, and a filter (Corning 0-52)
When irradiated with light of 300 nm or more, the absorbance gradually decreases, and the infrared absorption spectrum of the irradiated film shows double bond absorption (1610 cm ^-1 ).
A decrease was observed, indicating that a reaction occurred between double bonds. A film irradiated with light for 10 to 15 minutes is almost insoluble in common organic solvents, but a film irradiated for a short time, for example 2 minutes, is soluble in tetrahydrofuran, and the molecular weight determined by gel permeation chromatography is It was 1200-2500 (dimer-tetramer). Example 4 5,5'- purified by recrystallization from acetone
(1,4-phenylene)-bis(2-cyano-2,
A chloroform solution of di-n-amyl ester (4-pentadienoitsuccinic acid) (0.89 x 10 ^-3 M) and a chloroform solution of arachidic acid (0.89 x 10 ^-3 M) were mixed at a molar ratio of 1:5. This solution was gradually dropped onto the surface of a cadmium chloride aqueous solution (10 ^-3 M), developed, and then gradually compressed to measure the surface pressure-occupied area curve. The presence of a solid condensed phase was observed in this curve, confirming the formation of a monomolecular film. Therefore, the surface pressure was set to 30 dyn/cm to form a monomolecular film. Next, this monomolecular film was transferred to a quartz plate by a vertical dipping method to produce a cumulative film consisting of six monomolecular film layers. The absorption spectrum of this mixed cumulative film has an absorption maximum at 360 nm, and a xenon lamp is used as a light source, and a filter (Corning 0-
When irradiated with light of 300 nm or more using 52), the absorbance gradually decreased. The infrared absorption spectrum of the irradiated film showed a decrease in double bond absorption (1610 cm ^-1 ), indicating that a reaction occurred between double bonds. Membranes irradiated for 10 to 15 minutes are almost insoluble in common organic solvents, but membranes irradiated for a short time, for example 2 minutes, are soluble in tetrahydrofuran.
The molecular weight was 950-2500 (dimer-tetramer).

Claims (1)

[Claims] 1 5,5'-(1,4-phenylene)-bis(2- cyano-2,4-pentadienoitsuccinic acid) dialkyl ester or a mixture of this and an amphiphilic compound, and then irradiating the film with light. Production method.