JP2002193965A - Phthalimide derivative having oxetane ring - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new compound having oxetane rings (an oxetane compound), which can be converted into a resin having high heat resistance and high adhesion by photocuring and thermosetting. SOLUTION: The purpose of the invention is achieved by a phthalimide derivative having oxetane rings represented by formula (1) [wherein, R1 is H or a 1-6C alkyl group; R2 is a divalent hydrocarbon group which may includes, within its carbon chain, an ether linkage or a siloxane linkage.].

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a phthalimide derivative having an oxetane ring, which can be cured by light and heat, and a method for producing the same. The compound having an oxetane ring is a monomer that can be cured by light or heat, and the resin derived therefrom has excellent heat resistance, mechanical properties, adhesion, etc. It can be used as a material, adhesive or the like.

[0002]

BACKGROUND ART Compounds having an oxetane ring (oxetane compounds) are known as monomers capable of cationic polymerization.
It is a compound that has attracted attention in recent years, and many monofunctional and polyfunctional oxetane compounds have been reported.

[0003] For example, Pure Appl. Che
m. , A30 (2 & 3), pp. 189 (1993) describe a method for synthesizing various oxetane compounds.
No. 021858 discloses an oxetane compound represented by the formula (8) (wherein R ⁴ represents an alkyl group, an aryl group,
Represents an aralkyl group, a cycloalkyl group, or an aromatic residue having a valence of 2 or more, Et represents an ethyl group, and k is 1 or 2. ) Is described.

[0004]

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[0005] Also, Japanese Patent Application Laid-Open No. 6-16804 discloses that
An oxetane compound represented by the formula (9) is described (wherein R ⁵ is a hydrogen atom, a fluorine atom, a carbon number of 1 to 6).
, A fluoroalkyl group having 1 to 6 carbon atoms, an allyl group, an aryl group, a furyl group, or a thienyl group. R ⁶ represents a polyvalent group selected from a chain or branched poly (alkyleneoxy) group, a xylylene group, a siloxane bond, and an ester bond. Z represents an oxygen atom or a sulfur atom, and m is an integer of 2 to 4. ).

[0006]

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Further, Japanese Patent Application Laid-Open No. Hei 8-245783 describes a large number of oxetane compounds including a bifunctional oxetane having a 2,2′-bitrylenediyl skeleton. JP-A-10-212343 discloses an oxetane compound represented by the formula (10) (wherein R ⁷ is a hydrogen atom, a fluorine atom, an alkyl group having 1 to 6 carbon atoms, a fluoro group having 1 to 6 carbon atoms). An alkyl group, an allyl group, an aralkyl group, an aryl group, a furyl group, or a thienyl group, R ⁸ represents a hydrogen atom or a monovalent to tetravalent organic group, and has a valence corresponding to the value of p; Z represents an oxygen atom or a sulfur atom, and p is an integer of 1 to 4.).

[0008]

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Japanese Patent Application Laid-Open No. 2000-302774 discloses that
An oxetane compound represented by the formula (11) is also described (wherein R ⁹ represents an alkyl group having 1 to 6 carbon atoms;
¹⁰ represents a divalent aliphatic chain organic group having 2 to 16 carbon atoms. ).

[0010]

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[0011]

However, none of the known documents describes the oxetane compound of the present invention (a phthalic acid derivative having an oxetane ring), and no specific synthesis examples thereof. An object of the present invention is to provide a novel compound having an oxetane ring (oxetane compound) that can be derived into a resin having excellent heat resistance, adhesiveness, and the like by photocuring or thermal curing.

[0012]

The object of the present invention is solved by a phthalimide derivative having an oxetane ring represented by the formula (1). (In the formula, R ¹ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. R ² represents a divalent hydrocarbon group, and may contain an ester bond or a siloxane bond in the carbon chain. .)

[0013]

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[0014]

BEST MODE FOR CARRYING OUT THE INVENTION In the phthalimide derivative having an oxetane ring of the present invention represented by the above formula (1),
² is a divalent hydrocarbon group, which may contain an ether bond or a siloxane bond in its carbon chain. Examples of the hydrocarbon group include an alkylene group having 2 to 14 carbon atoms and an arylene group having 6 to 20 carbon atoms (an ether bond or a siloxane bond may be contained in the carbon chain). However, this carbon number does not include carbon atoms contained in siloxane bonds.

The hydrocarbon group includes, for example,-(C
H_Two)_Two-,-(CH_Two)_Three,-(CH _Two)_Four-,-(C
H_Two)_Five-,-(CH_Two)₆-,-(CH_Two)₈-,-(CH
_Two)_Ten-,-(CH_Two)₁₂Alk having 2 to 14 carbon atoms, such as
Len group, -C₆H_Four-(P-form or m-form), -C₆H_Four
-CH_Two-C₆H_Four6 to 2 carbon atoms such as-(p, p'-form)
0 arylene group, -C₆H_Four-OC₆H_Four− (P,
p'-isomer) having 6 to 20 carbon atoms having an ether bond.
Arylene group or polydimethyl represented by the formula (2)
A siloxane bond such as an alkylene group having a siloxane bond
Specific examples include an alkylene group having 2 to 14 carbon atoms having a bond.
It is listed. Among these hydrocarbon groups, alkylene
Group or an alkylene group having a siloxane bond is preferred.
No.

Further, in the phthalic acid derivative having an oxetane ring of the present invention, R ¹ is a hydrogen atom or a carbon atom having 1 to 6 carbon atoms.
Is an alkyl group. R ¹ is preferably an alkyl group having 1 to 6 carbon atoms (particularly, a methyl group or an ethyl group).

That is, in the phthalic acid derivative having an oxetane ring of the present invention, R ¹ is an alkyl group having 1 to 6 carbon atoms, and R ² is an alkyl group having 2 to 14 carbon atoms or a carbon atom having a siloxane bond. It is preferably an alkylene group having 2 to 14 atoms. Among them, R ¹ is a methyl group or an ethyl group, and R ² is an alkylene group having 2 to 14 carbon atoms or polydimethyl represented by the above formula (2). Those which are alkylene groups having a siloxane bond are more preferred.

The phthalic acid derivative having an oxetane ring of the present invention can be obtained by, for example, reacting trimellitic anhydride represented by the above formula (3) with a diamine represented by the above formula (4), ), And then esterifying the 4,4'-biscarboxyphthalimide to give a 4,4'-bisalkoxycarbonyl represented by the formula (6) It can be produced by producing phthalimide and reacting the 4,4′-bisalkoxycarbonylphthalimide with a 3-hydroxymethyloxetane compound represented by the above formula (7).

Examples of the diamine represented by the formula (4) include 1,2-diaminoethane (ethylenediamine), 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, Aliphatic diamines such as 1,6-diaminohexane (hexamethylenediamine), 1,8-diaminooctane, 1,10-diaminododecane and 1,12-diaminododecane, p-phenylenediamine, m-phenylenediamine, diaminodiphenylmethane Specific examples thereof include aromatic diamines having an ether bond such as diaminodiphenyl ether, and aliphatic diamines having a siloxane bond such as polydimethylsiloxane-α, ω-diamine. Among the diamines, an aliphatic diamine and an aliphatic diamine having a siloxane bond are preferable. In the diamine, R ² is the above-mentioned divalent hydrocarbon group.

Examples of the 3-hydroxymethyloxetane compound represented by the above formula (7) include 3-alkyl-3-hydroxymethyloxetane such as 3-methyl-3-hydroxymethyloxetane and 3-ethyl-3-hydroxymethyloxetane. Oxetane and 3-hydroxymethyloxetane are specifically exemplified. Among the 3-hydroxymethyloxetane compounds, 3-alkyl-3-hydroxymethyloxetanes (particularly, 3-methyl-3-hydroxymethyloxetanes, 3-ethyl-3-hydroxymethyloxetanes) are preferable. In the 3-hydroxymethyloxetane compound, R ¹ is the above-mentioned hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

The reaction (first reaction) between the diamine and trimellitic anhydride represented by the formula (3) can be carried out at 80 to 250 ° C., more preferably 100 to 200 ° C. in the presence of a reaction solvent. preferable. At this time, the amount of the diamine used is preferably 0.4 to 0.6 times mol, more preferably 0.45 to 0.55 mol, of trimellitic anhydride. The reaction time may usually be about 1 to 20 hours. The reaction pressure is not particularly limited, but the pressure may be reduced when water generated for promoting the reaction is distilled out of the system. When water is distilled off, a solvent azeotropic with water, such as benzene, toluene, or xylene, may be added to the reaction solvent. Instead of distilling off water, a dehydrating agent such as acetic anhydride can be added after the start of the reaction.

As the reaction solvent, N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone (NMP), 1,3-dimethyl-2-
Examples include imidazolidinone, dimethyl sulfoxide, sulfolane, cresol, chlorophenol, glyme, diglyme and the like. The use amount of the reaction solvent is not particularly limited, but it is preferable from the viewpoint of operation that the content of 4,4′-biscarboxyphthalimide to be generated is in the range of 5 to 40% by weight. One or more reaction solvents can be used.

After the completion of the first reaction, the reaction solution containing the product 4,4'-biscarboxylphthalimide can be directly used for the next esterification reaction. On the other hand, the reaction solution is poured into a poor solvent to precipitate a product, which is separated by filtration, dried, and then subjected to an esterification reaction of the obtained 4,4′-biscarboxylphthalimide. . Examples of such poor solvents include water, methanol, ethanol, isopropanol, acetone, tetrahydrofuran, diethyl ether, diisopropyl ether, toluene, xylene and the like.

Next, the 4,4'-biscarboxylphthalimide obtained in the first reaction is esterified with an esterifying agent to be converted to 4,4'-bisalkoxycarbonylphthalimide. Examples of the esterifying agent include lower alcohols having 1 to 4 carbon atoms such as methanol and ethanol,
Examples thereof include trialkyl orthoformate having a lower alkoxy group having 1 to 4 carbon atoms, such as trimethyl orthoformate and triethyl orthoformate. Of these, trialkyl orthoformate (particularly, trimethyl orthoformate and triethyl orthoformate) is preferable. The amount of the esterifying agent used is 4,4′-
It is preferably 2.0 to 15 times, more preferably 2.2 to 10 times the mole of biscarboxyphthalimide.

The esterification reaction (second reaction)
, It is preferable to use a catalyst because the reaction can be promoted. As the catalyst, sulfuric acid, hydrochloric acid, p-toluenesulfonic acid, protic acids such as trifluoroacetic acid,
Zinc chloride, titanium alkoxide (titanium butoxide, etc.)
And the like, but a protonic acid (particularly, sulfuric acid, p-toluenesulfonic acid) is preferable. The amount of the catalyst to be used is preferably 0.05 to 20 mol%, more preferably 0.1 to 10 mol%, based on 4,4′-biscarboxylphthalimide.

The second reaction is preferably carried out at 50 to 200 ° C., more preferably 80 to 180 ° C. in the presence of a reaction solvent if necessary. In this case, the same reaction solvent as used in the first reaction can be used. For example, an esterification agent and a catalyst can be added to the reaction solution of the first reaction, and the reaction can be efficiently performed as it is. The reaction time of the second reaction is 1 to 50
It should be about an hour.

After the completion of the second reaction, the product 4,4'-bisalkoxycarbonylphthalimide is separated from the reaction solution by operations such as solvent extraction, washing with water, drying and solvent removal. When the product is a solid at room temperature, the reaction solution is poured into a poor solvent to precipitate the product, which is then separated by filtration and dried to obtain 4,4′-bisalkoxycarbonylphthalimide. As such a poor solvent, the same solvent as in the first reaction can be used.

Next, the 4,4'- obtained in the second reaction is obtained.
The phthalimide derivative having an oxetane ring of the present invention can be produced by reacting a bisalkoxycarboquinylphthalimide with a 3-hydroxymethyloxetane compound represented by the above formula (7).
In this reaction (third reaction), a reaction solvent can be used, but no solvent is advantageous in terms of reaction rate. Further, it is preferable to carry out the reaction while distilling off the produced alcohol (particularly methanol or ethanol) because the reaction can be promoted. The reaction temperature is 80-250 ° C,
The temperature is preferably from 00 to 200 ° C., and the reaction pressure is preferably normal pressure or reduced pressure.

The amount of the 3-hydroxymethyloxetane compound used is 2 to 15 times the molar amount of 4,4'-bisalkoxycarbonylphthalimide, and more preferably 2.2 to 2 times.
It is preferably 10-fold molar, and the amount of catalyst used is
It is preferably 0.001 to 10 mol%, more preferably 0.05 to 5 mol%, based on 4,4′-bisalkoxycarbonylphthalimide. Examples of the catalyst include tetraalkoxytitanium (such as tetrabutoxytitanium), sodium alkoxide (such as sodium methoxide), dibutyltin oxide, tin 2-ethylhexanoate, lead acetate, zinc acetate, and potassium carbonate. Tin 2-ethylhexanoate is preferred.

After completion of the third reaction, the product represented by the above formula (1)
The phthalimide derivative represented by is separated from the reaction solution by operations such as solvent extraction, washing with water, drying, and solvent removal. When the product is a solid at room temperature, the reaction solution is poured into a poor solvent to precipitate the product, which is separated by filtration and dried.
The product can also be obtained. Such poor solvents include:
The same as in the first reaction can be used.

The phthalimide derivative represented by the above formula (1) obtained as described above has a ¹ H-NMR, ¹³ C-
It is a novel compound that can be confirmed by NMR, mass spectrum, and the like. This compound is capable of cationic polymerization. For example, JP-A-7-53711 and JP-A-11-435.
No. 40, Japanese Patent Application No. 11-11663, or the like, it can be polymerized in the same manner as a known oxetane compound. In particular, the compound of the present invention can be used as a photocurable or thermosetting monomer, and a resin derived therefrom has excellent properties such as heat resistance and adhesion,
It can be used for various resists and adhesives.

[0032]

EXAMPLES The present invention will be specifically described below with reference to examples. Example 1 [First reaction] Internal volume 20 equipped with a cooling pipe and a stirrer
In a 0 ml three-necked flask, trimellitic anhydride was added.
21 g (0.1 mol), 100 ml of NMP were charged,
While stirring, 5.81 g of hexamethylenediamine
(0.05 mol) was added. After the stirring was continued to make the solution uniform, the solution was heated to 160 ° C. and further stirred for 3 hours. After completion of the reaction, the reaction solution was cooled to room temperature,
and the resulting precipitate was filtered off. This was washed with a small amount of methanol and dried to obtain a white powder of 22.99.
g was obtained. This substance was analyzed by FD-MS, ¹ H-NMR, ¹³
When analyzed by C-NMR and IR, it was identified as a compound represented by the following formula (12) (see the following data). The yield was 99%.

[0033]

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FD-MS: molecular weight 464 ¹ H-NMR (DMSO-d ₆ , Me ₄ Si): δ
2 to 1.4 (m, 4H), 1.4 to 1.7 (m, 4H)
H) 3.53 (t, J = 7 Hz, 4H), 7.95
(D, J = 7.5 Hz, 2H), 8.20 (s, 6
H), 8.32 (d, J = 7.5 Hz, 2H), 13.
6 (bs, 2H) ¹³ C-NMR (DMSO-d ₆ , Me ₄ Si): δ 2
5.80, 27.67, 37.61, 122.94, 1
23.22, 132.05, 134.87, 135.1
0, 136.33, 165.72, 167.07 IR (cm ^-1 ): 1770 (m), 1700 (s)

[Second Reaction] The above formula (1) was placed in a 100 ml three-necked flask equipped with a cooling tube and a stirrer.
9.29 g (0.02 mol) of the compound represented by 2),
NMP 50 ml, trimethyl orthoformate 12.73 g
(0.12 mol), and 0.04 g (0.2 mmol) of p-toluenesulfonic acid monohydrate were added.
Stirred for 0 hours. After completion of the reaction, the reaction solution was cooled to room temperature, poured into 150 ml of water, and the resulting precipitate was separated by filtration.
This was washed with a small amount of methanol and then dried to obtain 9.59 g of a white powder. When this substance was analyzed by high performance liquid chromatography, the purity was 99%, and FD-M
Analysis by S, ¹ H-NMR and IR gave the following formula (13)
(See data below). The yield was 97%.

[0036]

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FD-MS: molecular weight 492 ¹ H-NMR (CDCl ₃ , Me ₄ Si): δ 1.3-
1.5 (m, 4H), 1.55 to 1.8 (m, 4H),
3.65 (t, J = 7 Hz, 4H), 4.00 (s, 6
H), 7.95 (d, J = 7.5 Hz, 2H), 8.4
0 (s, 2H), 8.45 (d, J = 7.5 Hz, 2
H) IR (cm ^-1 ): 1775 (m), 1705 (s), 1
260 (m)

[Third Reaction] The above-mentioned formula (13) was placed in a 50-ml three-necked flask equipped with a cooling tube and a stirrer.
4.92 g (0.01 mol) of a compound represented by the formula:
3.48 g of ethyl-3-hydroxymethyloxetane
(0.03 mol), dibutyltin oxide 0.002
5 g (0.01 mmol) was charged and stirred at 170 ° C. for 20 hours. After completion of the reaction, the reaction solution was cooled to room temperature, poured into 50 ml of diisopropyl ether, and the resulting precipitate was separated by filtration. This was dried to obtain 6.28 g of a white powder. When this substance was analyzed by high performance liquid chromatography, the purity was 95%, and FD-MS, ¹ H-NMR,
As a result of analysis by ¹³ C-NMR and IR, the compound was identified as a compound represented by the following formula (14) (see the following data). The yield was 95%.

[0039]

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FD-MS: molecular weight 660 ¹ H-NMR (CDCl ₃ , Me ₄ Si): δ 0.95
(T, J = 7.5 Hz, 6H), 1.3 to 1.5 (m,
4H), 1.55-1.75 (m, 4H), 1.85
(Q, J = 7.7 Hz, 4H), 3.70 (t, J = 7
Hz, 4H), 4.4 to 4.6 (m, 12H), 7.9
5 (d, J = 7.5 Hz, 2H), 8.35 to 8.45
(M, 4H) ¹³ C-NMR (CDCl ₃ , Me ₄ Si): δ 7.9
2, 25.72, 26.27, 27.57, 37.6
0, 42.33, 67.60, 76.50, 122.7
4, 123.36, 132.11, 134.78, 13
5.04, 135.25, 164.33, 166.85 IR (cm ^-1 ): 1770 (m), 1700 (s), 9
80 (m)

Example 2 [First reaction] A first reaction was carried out in the same manner as in Example 1 except that 3.71 g (0.05 mmol) of 1,3-propanediamine was used instead of hexamethylenediamine.

[Second reaction] After the completion of the first reaction, the reaction solution was cooled to room temperature, and 31.84 g of trimethyl orthoformate was obtained.
(0.30 mol) and 0.08 g (0.4 mol) of p-toluenesulfonic acid monohydrate were added at 120 ° C.
Stirred for hours. After completion of the reaction, a white powder was prepared in the same manner as in Example 1 except that the reaction solution was poured into 300 ml of water.
30 g were obtained. When this substance was analyzed by high performance liquid chromatography, its purity was 99%. As a result of analysis by ¹ H-NMR, it was identified as a compound represented by the following formula (15) (see the following data). The yield was 99%.

[0043]

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¹ H-NMR (CDCl ₃ , Me ₄ Si):
δ 2.0-2.2 (m, 2H), 3.80 (t, J =
7Hz, 4H), 4.00 (s, 6H), 7.95
(D, J = 7.5 Hz, 2H), 8.40 (s, 2
H), 8.45 (d, J = 7.5 Hz, 2H)

[Third reaction] The compound represented by the formula (13) was converted to the compound represented by the formula (15) 4.50 g (0.5.
01 mol), except that the third reaction was carried out in the same manner as in Example 1. After the completion of the reaction, 5.88 g of a white powder was obtained in the same manner as in Example 1. When this substance was analyzed by high performance liquid chromatography, the purity was 95% and FD-M
As a result of analysis by S, ¹ H-NMR and ¹³ C-NMR, it was identified as a compound represented by the following formula (16) (see the following data). The yield was 95%.

[0046]

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FD-MS: molecular weight 618 ¹ H-NMR (CDCl ₃ , Me ₄ Si): δ 0.95
(T, J = 7.5 Hz, 6H), 1.85 (q, J =
7.7 Hz, 4H), 2.05 to 2.2 (m, 2H),
3.75 (t, J = 7 Hz, 4H), 4.4-4.6
(M, 12H), 7.95 (d, J = 7.5 Hz, 2
H), 8.35~8.45 (m, 4H ) 13 C-NMR (CDCl 3, Me 4 Si): δ 8.0
2, 26.65, 35.67, 42.60, 67.6
0, 76.60, 123.21, 124.00, 13
2.08, 135.16, 135.28, 164.4
3,166.90

Example 3 [First reaction] 45.10 g of hexamethylenediamine was converted to α, ω-bis (3-aminopropyl) polydimethylsiloxane (average molecular weight: 902; manufactured by Dow Corning Toray).
(0.05 mmol), except that the first reaction was carried out in the same manner as in Example 1.

[Second Reaction] After the completion of the first reaction, a second reaction was carried out in the same manner as in Example 2. After completion of the reaction, the reaction solution was cooled to room temperature and poured into 300 ml of water, and toluene 3
Extracted with 00 ml. The toluene layer was dried over anhydrous magnesium sulfate, filtered over anhydrous magnesium sulfate, and distilled to remove toluene to obtain 63.9 g of a viscous liquid.

[Third reaction] A third reaction was carried out in the same manner as in Example 1, except that the compound represented by the formula (13) was replaced by the viscous liquid (12.78 g, 0.01 mol). . After completion of the reaction, the reaction solution was cooled to room temperature, poured into 100 ml of water, and extracted with 100 ml of toluene. The toluene layer was separated, dried over anhydrous magnesium sulfate, filtered over anhydrous magnesium sulfate, and toluene was distilled off.
3.74 g were obtained. This material was subjected to FD-MS, ¹ H-N
When analyzed by MR, it was identified as the compound represented by the following formula (17) (see the following data). The yield was 93% based on trimellitic anhydride.

[0051]

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FD-MS: molecular weight 1458 ¹ H-NMR (CDCl ₃ , Me ₄ Si): δ 0.0-
0.2 (m, 66H), 0.5 to 0.7 (m, 4H),
0.95 (t, J = 7.5 Hz, 6H), 1.5-1.
8 (m, 4H), 1.85 (q, J = 7.7 Hz, 4
H) 3.6-3.8 (m, 4H), 4.3-4.6
(M, 12H), 7.9-8.0 (m, 2H), 8.3
5 to 8.45 (m, 4H)

[0053]

According to the present invention, a novel oxetane compound which can be produced from easily available raw materials can be provided.
Such an oxetane compound can be cationically polymerized and can be polymerized in the same manner as a known oxetane compound. The phthalimide derivative having an oxetane ring of the present invention can be used for various resists and adhesives.

Continued on the front page F term (reference) 4C063 AA05 BB08 CC72 DD07 EE05 4H049 VN01 VP10 VQ60 VQ79 VR23 VR41 VS35 VS60 VU21 VU23 VW02 VW35 4J035 BA01 CA01K CA19U CA22M FB01 HB05 LB01 LB02 LB16

Claims (4)

[Claims] Phthalimide derivative (wherein having an oxetane ring represented by 1. A general formula (1), R ¹ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. Also, R ² is a divalent hydrocarbon Represents a hydrogen group and may contain an ether bond or a siloxane bond in the carbon chain.) Embedded image 2. The phthalimide derivative having an oxetane ring according to claim 1, wherein R ¹ is a methyl group or an ethyl group, and R ² is an alkylene group having 2 to 14 carbon atoms. 3. The phthalimide derivative having an oxetane ring according to claim 1, wherein R ¹ is a methyl group or an ethyl group, and R ² is an alkylene group having a polydimethylsiloxane bond represented by the general formula (2). In the formula, Me represents a methyl group, and n represents an integer of 1 to 20.) Embedded image 4. A trimellitic anhydride represented by the general formula (3) and a diamine represented by the general formula (4) (wherein R ²
Is the same as above. ) To produce 4,4′-biscarboxyphthalimide represented by the general formula (5) (wherein R ² is the same as described above). Embedded image Embedded image The 4,4'-biscarboxyphthalimide is esterified to give a 4,4'-bisalkoxycarbonylphthalimide represented by the general formula (6) (wherein R ² is the same as above, and R ³ has 1 carbon atom). Which represents an alkyl group of the formula: Its 4,4'-bis alkoxycarbonyl phthalimide general formula (7) 3-hydroxymethyl oxetane compound represented by (wherein, R ¹ is the same as defined above.) Is characterized in that is reacted with, wherein Item 10. A method for producing a phthalimide derivative having an oxetane ring according to Item 1. Embedded image