JP2014237598A - Compound and photo-base generator consisting of the compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new compound suitable as a photo-base generator, which can maintain high basicity for a long period of time with ultraviolet irradiation.SOLUTION: A compound is represented by the formula (1).

Description

  The present invention relates to a novel compound and a photobase generator comprising the compound.

  As a photosensitive material of resin such as polyimide or epoxy used in the field of electronic devices such as high-density printed circuit boards, a photoacid generator has been used in many cases. In the insulation treatment with a resin such as polyimide or epoxy, by adding this photoacid generator, the pattern of the connecting portion and the insulating portion can be formed by utilizing the curing reaction of the resin by ultraviolet irradiation. However, an insulating material using a photoacid generator has a problem that a metal wiring may be corroded by an acid generated by ultraviolet irradiation, resulting in a defect in the product. In the future, it is predicted that this problem will become more apparent in consideration of further miniaturization of the wiring of electronic devices.

  On the other hand, in order to solve such a problem, an insulating material to which a photobase generator that does not have a concern about metal corrosion is added has been developed. Examples of such a photobase generator include carbamate-based (urethane-based) photobase generators (for example, Patent Documents 1 to 5), α-aminoketone-based photobase generators (for example, Patent Document 6), Quaternary ammonium-based photobase generator (for example, Patent Document 7), O-acyloxime-based photobase generator (for example, Patent Document 8), photobase generator comprising an amine having a cyclopropenone ring (Patent Various photobase generators such as a photobase generator composed of [9] and [[(2-nitrobenzyl) oxy] carbonyl] alkylamine (Non-patent Document 1) are known.

  However, for example, the photobase generators of Patent Documents 1 to 6, 8, 9 and Non-Patent Document 1 have a relatively low basicity because the base generated by ultraviolet irradiation is a primary or secondary amine, and is particularly patentable. The photobase generators of Literatures 1-3, 6, 8, and 9 have a problem that they do not sufficiently exhibit the effect as a base generator in terms of base generation efficiency. In addition, the photobase generators of Patent Documents 4 and 5 are sensitive to the wavelength region of light rays called so-called h-rays (wavelength of about 405 nm), which has a longer wavelength than the ultraviolet rays that are usually used to form patterns. There is a problem that the area is specified. The quaternary ammonium salt-based photobase generator of Patent Document 7 has insufficient catalytic activity for curing the epoxy group, and the base generated by ultraviolet irradiation contains an ionic component, so that the insulation reliability is improved. There is concern in terms of.

  Therefore, by devising the molecular structure, it is desired to develop a photobase generator that generates a base having higher base generation efficiency and higher catalytic activity than conventional photobase generators.

Japanese Patent Laid-Open No. 10-77264 Japanese Patent Publication No. 51-46159 Japanese Patent Laid-Open No. 6-345711 International Publication No. 2010-38828 International Publication No. 2010-38837 JP-A-11-71450 JP 2005-264156 A JP 2006-36895 A JP 2011-195616 A

J. Am. Chem. Soc., 113, 4303-4313 (1991)

  An object of the present invention is to provide a novel compound suitable as a photobase generator, which can maintain a high basicity for a long time by irradiation with ultraviolet rays.

  The compound of the present invention is represented by the following formula (1).

The photobase generator of the present invention comprises the above formula (1).

  The compound represented by the formula (1) of the present invention is not ionic in structure but is formed from neutral organic molecules, and therefore has high compatibility with an organic medium, particularly in an organic medium such as a resin. On the other hand, it can be dispersed very uniformly at an arbitrary ratio.

When a solution obtained by dissolving the compound represented by the formula (1) of the present invention in various solvents such as dichloromethane is irradiated with ultraviolet rays having a wavelength of 250 to 350 nm, it decomposes and is represented by the formula (2) 1, 2-Bis (tetramethylguanidino) ethyne is generated and carbon monoxide is generated. 1,2-bis (tetramethylguanidino) ethyne exhibits high basicity and can exist stably in an air atmosphere, so that high basicity is maintained for a long time.
Therefore, the compound represented by the formula (1) of the present invention is suitable as a photobase generator.

FIG. 1 is a diagram showing a ¹ H-NMR spectrum of compound (1). FIG. 2 is a diagram showing a ¹³ C-NMR spectrum of compound (1). FIG. 3 is a diagram showing an IR spectrum of the compound (1). FIG. 4 is a diagram showing a UV-Vis spectrum of compound (1).

  Hereinafter, the compound represented by Formula (1) of this invention is demonstrated in detail. Hereinafter, the compound of the present invention is also referred to as “compound (1)”.

The production method of the compound (1) is not particularly limited as long as the object of the present invention is not impaired. For example, J. Am. Chem. Soc., 93, 2573-2574 (1971) and J. Am Referring to the method described in Chem. Soc., 95, 3043-3045 (1973), it can be produced by the following method.

  Sodium trichloroacetate and trichloroethylene are dissolved in a solvent such as 1,2-dimethoxyethane (DME) and heated to reflux to obtain pentachlorocyclopropane.

  To the obtained pentachlorocyclopropane, an aqueous potassium hydroxide solution in which 2.6 equivalents of potassium hydroxide was dissolved with respect to the pentachlorocyclopropane was added, and the mixture was stirred at 75 ° C. for 30 minutes. Cyclopropene is obtained.

  After adding 5 equivalents of 1,1,3,3-tetramethylguanidine to a solution of tetrachlorocyclopropene dissolved in dichloromethane and stirring for 3 hours, 70% aqueous perchloric acid solution was added, and the external temperature was increased. The compound represented by the formula (3) (hereinafter referred to as “compound (3)” as a perchlorate of a cyclopropenium cation having three tetramethylguanidine-derived skeletons by further stirring while cooling to 0 ° C. "). At this time, in the process of synthesizing the compound (3) from tetrachlorocyclopropene, it is presumed that it goes through an intermediate in which four skeletons derived from tetramethylguanidine are bonded to cyclopropene.

  Further, the compound (1) is obtained by stirring the compound (3) in a methanol solution of 4N potassium hydroxide.

In addition, the said reaction example shows an example of the manufacturing method of a compound (1) as already stated, It can manufacture using not only the said manufacturing method but a various well-known method.

The structure of the compound (1) can be confirmed by nuclear magnetic resonance spectroscopy ( ¹ H-NMR and ¹³ C-NMR) and infrared spectroscopy (IR).
That is, in the ¹ H-NMR spectrum, a peak based on a methyl group substituted on the nitrogen atom of guanidine is observed at 2.93 ppm.

^{In the 13} C-NMR spectrum, a peak based on a methyl group substituted on the nitrogen atom of guanidine is observed at 39.70 ppm, a peak based on guanidine carbon is observed at 131.09 ppm, and it is based on the carbonyl carbon of the cyclopropenone ring. A peak is observed at 146.51 ppm, and a peak based on carbon other than the carbonyl carbon of the cyclopropenone ring is observed at 167.17 ppm. The results of the ¹ H- and ¹³ C-NMR spectra were obtained under the measurement conditions of ¹ H resonance frequency of 400 MHz using tetramethylsilane (TMS) as an internal standard substance.

In the infrared (IR) spectrum, a peak derived from the carbonyl group of the cyclopropenone ring is observed at 1834 cm ⁻¹ .
In the ultraviolet-visible (UV-Vis) spectroscopic analysis, an absorption maximum (λ _max ) is observed around 319 nm.

  When a compound in which the compound represented by the above formula (1) is dissolved in, for example, dichloromethane is irradiated with ultraviolet rays having a wavelength of 250 to 350 nm, 1,2-bis (tetramethylguanidino) ethyne represented by the following formula (2) And carbon monoxide is generated.

This 1,2-bis (tetramethylguanidino) ethyne has a pH value of 10.6 and can exist stably in an air atmosphere.

  In the present invention, examples of the solvent for dissolving the compound (1) include polar organic solvents such as chloroform, acetone, methanol, ethanol and toluene in addition to dichloromethane. Further, for example, a mixed solvent in which acetone and water are mixed at a volume ratio of 9: 1 may be used.

  As described above, the compound (1) of the present invention easily produces 1,2-bis (tetramethylguanidino) ethyne represented by the formula (2) when irradiated with ultraviolet rays having a wavelength of 250 to 350 nm. . Since 1,2-bis (tetramethylguanidino) ethyne has a pH value of 10.6, it is considered that the effect as a base generator is sufficiently exhibited in terms of base generation efficiency.

The 1,2-bis (tetramethylguanidino) ethyne produced by irradiating the solution of the compound (1) with ultraviolet rays is confirmed using, for example, the method described below.
A solution in which compound (1) is dissolved in dichloromethane or the like is prepared, and the pH value at room temperature is measured. Next, the solution is irradiated with ultraviolet rays (wavelength 254 nm; illuminance 614 μW / cm ² ), and the pH value thereafter is measured.

  A change in pH is observed before and after UV irradiation, and when the pH value increases before and after UV irradiation, specifically, a base is generated when the pH value is less than 7.0 to a value higher than 7.0. When the pH value before light irradiation is 7.0 or higher and becomes higher after irradiation, it is recognized that the base has increased.

  By the way, the compound (1) of this invention has an effect | action as a dissolution inhibitor with respect to alkaline aqueous solution. A dissolution inhibitor refers to a substance having an action of reducing the solubility of an alkali-soluble compound in an alkali by mixing with the alkali-soluble compound. Compound (1) is decomposed as shown in the above formula by irradiating with ultraviolet rays having a wavelength of 250 to 350 nm to produce 1,2-bis (tetramethylguanidino) ethyne which is a base. It disappears and the solubility is higher than that of the system of the alkali-soluble polymer alone. This is presumably because the produced 1,2-bis (tetramethylguanidino) ethyne acts as a dissolution accelerator.

The compound (1) of the present invention can be used together with an alkali-soluble polymer.
Specific examples of the alkali-soluble polymer include poly (p-hydroxy-α-methylstyrene), poly (p-hydroxystyrene), poly (p-vinylbenzoic acid), polyacrylic acid, and polymethacrylic acid. A styrene / maleic acid copolymer, a styrene / acrylic acid copolymer, a styrene / methacrylic acid copolymer, a novolac resin, and the like are used, but the present invention is not limited thereto.

  However, as will be described later, in the method for producing a negative resist, a carboxyl group-containing alkali-soluble polymer is particularly used as the alkali-soluble polymer. Examples of such a carboxyl group-containing alkali-soluble polymer include poly (p-vinylbenzoic acid), polyacrylic acid, polymethacrylic acid, styrene / maleic acid copolymer, styrene / acrylic acid copolymer, and styrene / acrylic acid copolymer. A methacrylic acid copolymer or the like is used.

  The compounding ratio of the alkali-soluble polymer (hereinafter also simply referred to as “A”) and the photobase generator (hereinafter also simply referred to as “B”) in the resist pattern forming material is A / B (weight ratio). ) Is usually 100/50 to 100/5, preferably about 100/35 to 100/5.

  In addition to the photobase generator and the alkali-soluble polymer, the resist pattern forming material may contain a diluent, a sensitizer, a dye, or the like as long as the object of the present invention is not impaired.

From the resist pattern forming material, both positive and negative resist patterns can be formed.
In the method for producing a positive resist, the resist pattern forming material is applied and dried on a substrate to be processed made of Si, Ga, As, or the like to produce a coating film. The thickness of the coating film is usually about 0.5 to 10 μm, preferably about 0.5 to 5 μm, and particularly preferably about 0.5 to 2 μm. Next, the coating film is irradiated with ultraviolet rays having a wavelength of 250 to 350 nm in a desired pattern. Irradiation with ultraviolet rays is performed through a mask, for example. UV exposure is usually 0.5 J / cm ² or more, preferably 1~100J / cm ^2. In the coating film of the part irradiated with ultraviolet rays (hereinafter referred to as “ultraviolet irradiation part”), as described above, the compound (1) is decomposed to generate a base and the dissolution inhibitory property disappears, and the alkali-soluble property. Rises. On the other hand, in the coating film in the part not irradiated with ultraviolet rays (hereinafter referred to as “ultraviolet non-irradiated part”), the dissolution inhibition property remains, so that the alkali solubility remains lowered. Therefore, when the coating film is developed with an alkaline aqueous solution in this state, the ultraviolet irradiation part is washed away and the ultraviolet non-irradiation part remains, and a positive resist is obtained.

  In the negative resist preparation method, the coating film is prepared and exposed in the same manner as in the positive resist preparation method, and the carboxyl group-containing alkali-soluble polymer described above is used as the alkali-soluble polymer. And, prior to development, the coating film is usually heat treated. The heat treatment is usually performed at 80 to 180 ° C, preferably 110 to 150 ° C, particularly preferably 115 to 140 ° C for about 1 to 30 minutes. By performing the heat treatment, the base generated by the decomposition of the photobase generator reacts with the carboxyl group of the carboxyl group-soluble polymer in the ultraviolet irradiation part, and the carboxyl group is eliminated. As a result of elimination of the carboxyl group, the polymer loses alkali solubility. Accordingly, the ultraviolet irradiation part is insoluble in alkali. On the other hand, although the ultraviolet non-irradiated part has reduced solubility in alkali due to compound (1), it does not completely lose alkali solubility, so the developer or development time is appropriately set. Can be removed. Specifically, as a developing solution, a 2 to 4% aqueous solution of strong alkaline trimethylammonium hydroxide or the like is used, or the development time is increased to, for example, 60 seconds or more, so that the ultraviolet non-irradiated part Can be removed. By such treatment, the ultraviolet non-irradiated part is washed away, and the ultraviolet irradiated part remains, and a negative resist is obtained.

EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to this.
The method for identifying the reaction product and evaluating the basicity is as follows.

[1] Identification of reaction product (1) Nuclear magnetic resonance method ( ¹ H- and ¹³ C-NMR)
Apparatus: JNM-AL400 FT-NMR (manufactured by JEOL Ltd.)
Measurement conditions Internal standard: Tetramethylsilane (TMS)
¹ H resonance frequency: 400 MHz
(2) Ultraviolet / visible (UV-Vis) spectroscopy apparatus: SLUV-4 (manufactured by ASONE Corporation)
Measurement conditions Wavelength: 254nm
Light intensity: 614 μW / cm ²

[2] Basicity evaluation apparatus: pH meter (product name “PHM-103” manufactured by Toa DKK Co., Ltd.)
Measurement method: Glass electrode method It confirmed as follows according to the method described in the international publication 2008/072651.

The pH value at room temperature of a solution in which compound (1) is dissolved in dichloromethane is measured. Subsequently, the solution is irradiated with ultraviolet rays, and the subsequent pH value is measured after 30 minutes.
When pH changes before and after the light irradiation and the pH value increases before and after the light irradiation, specifically, when the pH value is less than 7.0 to a value higher than 7.0, the basicity When the pH value before light irradiation is 7.0 or higher and becomes higher after irradiation, it is recognized that the basicity has increased.

[Example 1]
[1] Synthesis of pentachlorocyclopropane 1 kg (5.366 mol) of sodium trichloroacetate and 3.56 L (36.6 mol) of trichloroethylene were dissolved in 556 mL of 1,2-dimethoxyethane (DME) and reacted by heating to reflux. I let you. When the reaction was completed, the reaction solution was washed with tap water 1.5 times that of sodium trichloroacetate, dried over sodium sulfate, and concentrated. The resulting brown syrup was distilled under reduced pressure to obtain 438 g of the desired product.

[2] Synthesis of tetrachlorocyclopropene In 435 g (2 mol) of pentachlorocyclopropane, 291 g (5.2 mol) of potassium hydroxide, 2.6 times the amount of the pentachlorocyclopropane, was dissolved in 380 mL of water. An aqueous potassium hydroxide solution was added and reacted at 75 ° C. for 30 minutes. The reaction solution was cooled to room temperature, the same amount of hexane as the aqueous potassium hydroxide solution was added, and the organic layer was separated into an aqueous layer. The organic layer was dried with mirabilite and concentrated. The resulting yellow syrup was distilled at atmospheric pressure to obtain 264 g of the desired product.

[3] Synthesis of Compound (3) 10 g (56.4 mmol) of tetrachlorocyclopropene was dissolved in 120 mL of dichloromethane, and 52.2 amount of 1,2,3,3-tetramethylguanidine (32.2 g, 282 mmol) was added. After stirring for 30 minutes, 50 mL of 70% aqueous perchloric acid solution was added, and the mixture was further stirred for 30 minutes while cooling the external temperature to 0 ° C. Double the amount of tap water of 70% perchloric acid aqueous solution was added to precipitate the reaction product, and the solid was collected by filtration to obtain the desired product.

[4] Synthesis of Compound (1) To 24.8 g (51.8 mmol) of Compound (3), 4N aqueous potassium hydroxide solution in which 6.7 g of potassium hydroxide was dissolved in 30 mL of water was added, and 10 volumes of methanol was added. And stirred at 50 ° C. for 12 hours. The reaction solution was cooled to room temperature and a large amount of saline was added. Then, the same amount of dichloroethane as methanol was added, extraction was performed, and the organic layer was dried with mirabilite and concentrated. The obtained brown syrup was subjected to silica gel column chromatography in a developing system of chloroform: methanol = 3: 1 to obtain 2 g of the desired product in a yield of 13.8%.

With respect to compound (1), the measurement results of nuclear magnetic resonance spectrum ( ¹ H-NMR and ¹³ C-NMR), UV-Vis spectrum and IR spectrum are shown below.
¹ H-NMR (400 MHz, CDCl ₃ ) δ: 2.93 ppm (—CH ₃ , methyl, 24H),
¹³ C-NMR (400 MHz, CDCl ₃ ) δ: 39.70 (methyl), 131.09 (guanidine carbon), 146.51 (carbonyl carbon of cyclopropenone ring), 167.17 (carbonyl of cyclopropenone ring) Carbon other than carbon)
UV-Vis spectrum: λ _max 319 nm
IR spectrum: 1834 cm ⁻¹ (Cyclopropenone ring carbonyl group)

[Example 2]
Compound (1) 7.22mg was dissolved in dichloromethane 10mL. 1 mL of this solution was collected and diluted to 10 mL with dichloromethane. The pH value at this time was 7.5.

  The dichloromethane solution was placed in a quartz cell for UV measurement, and irradiated with ultraviolet rays having a wavelength of 254 nm in a light-shielded / air atmosphere. Table 1 shows the results of changes in pH value with time when irradiated with ultraviolet rays.

  For comparison, the pH value of dichloromethane (blank) was measured and found to be 6.24.

Compound (1) is presumed to be decomposed as shown in the following formula.

As is clear from the results in Table 1, the solution in which compound (1) was dissolved in dichloromethane had a pH of 7.5 before the ultraviolet irradiation, but the pH value was 10 after 60 minutes after the ultraviolet irradiation. The basicity is maintained even after 3 hours. From this result, it can be seen that the compound represented by the formula (1) of the present invention is useful as a photobase generator.

Claims (2)

A compound represented by the following formula (1).
The photobase generator which consists of a compound represented by following formula (1).