KR101246278B1 - Synthetic method of iminodiacetic acid - Google Patents

Abstract

PURPOSE: A synthetic method of iminodiacetic acid is provided to improve the yield of iminodiacetic acid, and to minimize the generation of waste water and by-products in the synthetic process of iminodiacetic acid. CONSTITUTION: A synthetic method of iminodiacetic acid comprises a step of dropping 37%(w/w) formaldehyde into the mixture of H2O and glycine, and obtaining 2-(hydroxymethyl amino)acetic acid; a step of adding a sulfite and sodium cyanide into the 2-(hydroxymethyl amino)acetic acid in order, and obtaining 2-(cyanomethyl amino)acetic acid; a step of adding H2O and sulfuric acid into the 2-(cyanomethyl amino)acetic acid, and stirring the mixture to obtain iminodiacetic acid; and a step of purifying the iminodiacetic acid by methanol.

Description

Synthetic Method of Iminodiacetic Acid

The present invention relates to a method for synthesizing iminodiacetic acid, and more particularly, in the synthesis process of iminodiacetic acid, which is an LCD etchant etching additive, synthesis of iminodiacetic acid which can suppress the generation of wastewater and by-products and improve the yield. It is about a method.

In order to form a metal wiring on a substrate in a semiconductor device, a metal film forming process by sputtering or the like, a photoresist forming process having a predetermined pattern on the metal film, and an etching process for etching using the photoresist as a contact mask The etching process is performed by dry etching using plasma or wet etching using an etching solution. In the case of dry etching, since etching conditions are difficult and expensive, such as requiring a high vacuum, wet etching is more advantageous when an appropriate etching solution is present.

On the other hand, the resistance of the metallization film in the TFT-LCD device is a major factor causing the RC signal delay, and obtaining a low resistance metallization film is a key to increasing the panel size and high resolution. Therefore, in the prior art, chromium, molybdenum, aluminum nidium, and alloys thereof, which are used as materials for metal wiring films, have high resistance, and thus, they are not suitable for use as gates and data wirings used in large-sized TFT-LCDs. ought.

In this regard, copper metals, which are significantly lower in resistance than aluminum or chromium and have no environmental problems, are attracting attention as low-resistance wiring film materials. However, in the case of copper, photoresist is applied to the metal film by patterning. There are many problems such as poor adhesion to the glass substrate and the silicon insulating film. Rather than using copper alone to solve this problem, a technique of using an intermediate metal film together to increase the adhesion between the copper film and the lower glass substrate or the silicon insulating film and to suppress the diffusion of copper into the silicon film has been proposed. The intermediate metal film may include titanium, molybdenum or molybdenum alloy.

The etching of copper in the metal wiring is mainly performed using an etching solution such as ferric chloride + hydrochloric acid and ammonium persulfate. Most of these etching solutions have a high etching rate, but the etching solution composition is unstable and easily decomposed, and thus, the selectivity to copper etching is poor, thereby damaging other metal films exposed to the etching solution such as titanium, molybdenum, or molybdenum alloy. Therefore, there is a need to develop a highly selective copper etching solution that does not damage other metal films such as titanium, molybdenum, or molybdenum alloy while having an etching on the copper film.

Korean Patent Application Publication No. 10-2010-0040352 (2010.01.20.) Proposes a copper etchant having a high selectivity including hydrogen peroxide, phosphoric acid, phosphate, chelating agent, cyclic amine compound, and water. Iminodiacetic acid is used as a chelating agent.

On the other hand, US Patent No. 7,064,235 (2006.06.20.) Discloses a method for synthesizing imino diacetic acid.

The synthesis method has the advantage of being able to produce imino diacetic acid at a low cost and high purity, but waste water and by-products are generated in the synthesis process, there is a problem that the yield is not high.

Accordingly, the present inventors have developed a method for synthesizing iminodiacetic acid which can suppress the generation of wastewater and by-products and improve the yield.

KR 10-2010-0040352 A 2010.01.20. US 7,064,235 B2 2006.06.20.

It is an object of the present invention to provide a method for synthesizing iminodiacetic acid which can suppress the generation of waste water and by-products and improve the yield.

In order to achieve the above object, the present invention provides the following means.

In the present invention, 60 to 65 parts by weight of glycine (Glycine) is added to 100 parts by weight of H ₂ O, followed by stirring for 10 minutes, and then 70 to 75 parts by weight of 37% (w / w) formaldehyde is added dropwise at 60 ° C. Reacting for 1 hour to obtain 2- (hydroxymethylamino) acetic acid (step 1); After stirring by adding 15-20 parts by weight of sulfuric acid (H ₂ SO ₄ ) to 100 parts by weight of 2- (hydroxymethylamino) acetic acid, 20-25 parts by weight of sodium cyanide was added dropwise and reacted at 50 ° C. for 1 hour. To obtain 2- (cyanomethylamino) acetic acid (step 2); After adding 85 to 90 parts by weight of H ₂ O and 10 to 15 parts by weight of sulfuric acid (H ₂ SO ₄ ) to 100 parts by weight of 2- (cyanomethylamino) acetic acid, the mixture was stirred at 40 ° C. for 5 hours to obtain Iminodiacetic acid. Step (step 3); And purifying by adding 2-7 parts by weight of methanol at 1-5 ° C. to 100 parts by weight of the Iminodiacetic acid (step 4); It provides a method for synthesizing iminodiacetic acid (Iminodiacetic acid) comprising a.

In step 1, the 37% (w / w) formaldehyde (Formaldehyde) is characterized in that dropping for 30 minutes at 25 ℃ under N ₂ Purge.

In step 2, the 2- (hydroxymethylamino) acetic acid was cooled to 20 ° C., followed by addition of sulfuric acid (H ₂ SO ₄ ) to adjust the pH to 4-5, and stirred at room temperature for 10 minutes, followed by sodium cyanide. ) Is added dropwise at 10 ~ 25 ℃.

In step 3, sulfuric acid (H ₂ SO ₄ ) is reacted with H ₂ O for 30 minutes, and then dropwise added to the 2- (cyanomethylamino) acetic acid at 20 ℃ to adjust the pH to 1 ~ 2.5.

The method for synthesizing iminodiacetic acid according to the present invention has the advantage of synthesizing the imino diacetic acid with a yield of 97.6% and a purity of 99.95%, and has the effect of suppressing the generation of wastewater and by-products.

1 and a chemical scheme illustrating the mechanism of the synthesis reaction according to the present invention.
Figure 2 is an LC analysis of the iminodiacetic acid synthesized by the synthesis method of the present invention.
Figure 3 shows the IR analysis of iminodiacetic acid-reference.
Figure 4 is an IR analysis of the iminodiacetic acid synthesized by the synthesis method of the present invention.
5 is Proton NMR analysis of iminodiacetic acid-STD.
6 is a result of Proton NMR analysis of iminodiacetic acid synthesized by the synthesis method of the present invention.

Hereinafter, the present invention will be described in detail.

Iminodiacetic acid can be etched to increase the etching effect because it can maintain the etching ability by chemical stability between each additive such as hydrogen peroxide, phosphoric acid and nitric acid, which are the main raw materials of Etchant, in semiconductor and TFT-LCD fields. It is used as an additive.

Iminodiacetic acid prepared by the conventional synthetic method is a waste water and by-products are generated and has a disadvantage that the yield is not high.

The present invention is characterized by providing a method for synthesizing iminodiacetic acid which can suppress the generation of waste water and by-products and improve the yield.

Figure 1 is a chemical reaction illustrating the mechanism of the synthesis reaction according to the present invention.

Referring to Figure 1, a method for synthesizing iminodiacetic acid according to the present invention will be described.

Synthesis method of iminodiacetic acid of the present invention,

60 to 65 parts by weight of glycine (Glycine) was added to 100 parts by weight of H ₂ O, followed by stirring for 10 minutes. Then, 70 to 75 parts by weight of 37% (w / w) formaldehyde was added dropwise thereto at 60 ° C. for 1 hour. Reacting to obtain 2- (hydroxymethylamino) acetic acid (step 1);

After stirring by adding 15-20 parts by weight of sulfuric acid (H ₂ SO ₄ ) to 100 parts by weight of 2- (hydroxymethylamino) acetic acid, 20-25 parts by weight of sodium cyanide was added dropwise and reacted at 50 ° C. for 1 hour. To obtain 2- (cyanomethylamino) acetic acid (step 2);

After adding 85 to 90 parts by weight of H ₂ O and 10 to 15 parts by weight of sulfuric acid (H ₂ SO ₄ ) to 100 parts by weight of 2- (cyanomethylamino) acetic acid, the mixture was stirred at 40 ° C. for 5 hours to obtain Iminodiacetic acid. Step (step 3); And

Purifying by adding 2-7 parts by weight of methanol at 1-5 ° C. to 100 parts by weight of Iminodiacetic acid (step 4);

.

In step 1, the 37% (w / w) formaldehyde (Formaldehyde) is preferably added dropwise for 30 minutes at 25 ℃ under N ₂ Purge.

In step 2, the 2- (hydroxymethylamino) acetic acid was cooled to 20 ° C., followed by addition of sulfuric acid (H ₂ SO ₄ ) to adjust the pH to 4-5, and stirred at room temperature for 10 minutes, followed by sodium cyanide. ) Is preferably added dropwise at 10 to 25 ° C.

In step 3, after reacting H ₂ O with sulfuric acid (H ₂ SO ₄ ) for 30 minutes, it is preferable to drop the 2- (cyanomethylamino) acetic acid at 20 ° C. to adjust the pH to 1 to 2.5.

Synthesis method of the present invention has the advantage of synthesizing the imino diacetic acid of 97.6% yield and 99.95% purity, there is an effect that can suppress the generation of waste water and by-products.

The synthesis method according to the present invention will be described in detail through the following Preparation Examples and Examples.

[Production Example 1]

Add 48 g of H ₂ O to the reaction vessel, add 30 g of glycine, and stir for 10 minutes. Then, 30-50 g of 37% (w / w) formaldehyde (formaldehyde) at 25 ° C. under N ₂ Purge. It was added dropwise for 30 minutes and reacted for 1 hour at 50 ~ 60 ℃ to obtain 2- (hydroxymethylamino) acetic acid. (Step 1)

After cooling the 2- (hydroxymethylamino) acetic acid to 20 ° C., slowly adding 5-40 g of sulfuric acid (H ₂ SO ₄ ) to pH 4-5, stirring at room temperature for 10 minutes, and sodium cyanide. 20-25 g was added dropwise at 15 ° C. and reacted at 50 ° C. for 1 hour to obtain 2- (cyanomethylamino) acetic acid. (Step 2)

After reacting 30-180 g of H ₂ O with 0-70 g of sulfuric acid (H ₂ SO ₄ ) for 30 minutes, the mixture was added dropwise to 2- (cyanomethylamino) acetic acid at 20 ° C., adjusted to pH 1-2.5, at 40-80 ° C. Stirring for 4-7 hours gave Iminodiacetic acid. (Step 3)

0 to 20 g of methanol, acetone, or water at 5 ° C. was purified to the Iminodiacetic acid. (Step 4)

[Experimental Example 1]

In the synthesis in Preparation Example 1, the formaldehyde content of step 1, the reaction temperature of step 1, the sulfuric acid (H ₂ SO ₄ ) content of step 2, the sodium cyanide content of step 2 Yield change was experimented by adjusting, adjusting sulfuric acid (H ₂ SO ₄ ) and H ₂ O content of step 3, adjusting reaction temperature and reaction time of step 3, and adjusting the type and content of washing agent of step 4, The results are shown in Table 1.

G: Glycine

F: Formaldehyde

T1: reaction temperature in step 1

S2: sulfuric acid (H ₂ SO ₄ ) in step 2

N: Sodium cyanide

S3: sulfuric acid (H ₂ SO ₄ ) in step 3

O: H ₂ O in step 3

T3: reaction temperature in step 3

H: reaction time in step 3

W: washing in step 4

a: washing agent acetone

m: washing agent methanol (MeOH)

w: washing agent H ₂ O

-: N / A

G
(g) F
(g) T1
(℃) S2
(g) N
(g) S3
(g) O
(g) T3
(℃) H
(hr) W
(g) Yield
(%) 30 30 60 5 20 35 150 50 4 a 10 65 30 30 60 9 20 35 140 50 4 a 10 68 30 34 60 3 20 38 160 50 4 m 10 56 30 34 60 15 25 21 160 50 5 m 10 75 30 34 60 20 25 20 140 40 5 m 10 97.6 30 34 60 20 25 20 160 40 5 a 10 90 30 34 60 20 25 20 160 40 5 w 20 88 30 34 60 25 25 15 140 40 5 - 60 30 34 60 25 25 15 140 40 5 m 10 60 30 34 60 25 25 15 140 40 5 w 20 60 30 34 60 25 25 15 160 47 5.5 - 80 30 34 60 25 25 20 180 47 5.5 - 84 30 34 50 40 25 15 140 50 5 w 20 78 30 34 50 40 25 15 160 50 5 w 20 75 30 34 60 40 25 15 140 50 5 w 20 78 30 34 60 40 25 15 160 70 5 w 20 73 30 35 60 25 25 15 160 40 5 - 65 30 35 50 25 25 15 160 50 5 w 20 77 30 38 60 15 20 27 160 50 5 m 10 73 30 38 60 15 25 27 160 50 5 m 15 80 30 39 60 4 20 - 40 80 6 a 10 80 30 39 60 4 20 - 40 60 6 a 15 70 30 39 60 4 20 15 40 60 6 a 15 70 30 39 60 4 20 15 35 60 6 a 10 74 30 39 60 4 20 15 30 60 6 a 10 79 30 39 60 4 20 15 35 50 6 a 10 75 30 39 60 4 20 15 30 50 6 a 15 82 30 39 60 4 20 30 30 50 6 a 10 75 30 39 60 4 20 60 40 50 6 a 10 90 30 39 60 4 20 70 40 50 6 a 10 88 30 39 60 8 20 - 40 80 6 a 10 75 30 39 60 8 20 - 40 60 5 a 10 75 30 39 60 8 20 - 40 60 6 - 75 30 39 60 8 20 - 40 60 6 - 65 30 39 60 10 20 - 40 80 7 a 10 83 30 39 60 10 20 - 40 60 6 a 10 80 30 39 60 10 20 - 40 60 6 a 10 80 30 39 60 30 20 - 40 60 6 a 10 60 30 40 60 30 20 38 160 50 4 m 10 60 30 41 60 4 20 15 40 60 6 a 10 73 30 41 60 8 20 - 40 80 6 a 10 72 30 41 60 8 20 - 40 60 6 a 10 80 30 41 60 8 20 - 40 60 5 - 60 30 43 60 15 25 21 160 50 5 m 10 76

Looking at the results of Table 1, formaldehyde (Formaldehyde) content of step 1, 34g, reaction temperature of 60 ° C in step 1, 20g of sulfuric acid (H ₂ SO ₄ ) in step 2, sodium cyanide in step 2, 25g, Yield is 97.6% when synthesized under the conditions of 20 g of sulfuric acid (H ₂ SO ₄ ) in step 3 and 140 g of H ₂ O, reaction temperature of 60 ° C. in step 3 and reaction time of 5 hours, and 10 g of washing methanol in step 4 It can be confirmed that the highest.

[Production Example 2]

Except for using sodium cyanide (Potassium cyanide) instead of sodium cyanide the remainder was synthesized in the same manner as in Preparation Example 1.

[Experimental Example 2]

In the synthesis in Preparation Example 2, the formaldehyde content of step 1, the sulfuric acid (H ₂ SO ₄ ) content of step 2, the potassium cyanide content of step 2, the sulfuric acid of step 3 Yield change according to the control of H ₂ SO ₄ ), the reaction temperature of step 3, the type and content of the washing agent of step 4 was tested, and the results are shown in Table 2.

K: Potassium cyanide

G
(g) F
(g) T1
(℃) S2
(g) K
(g) S3
(g) O
(g) T3
(℃) H
(hr) W
(g) Yield
(%) 30 34 60 25 25 20 160 50 5 w 16 80 30 34 60 25 25 15 160 50 5 w 16 72 30 40 60 25 25 20 160 60 5 - 80 30 40 60 25 20 20 160 60 5 a 10 70 30 45 60 25 25 20 160 50 5 w 16 87 30 45 60 25 25 20 160 50 5 m 10 75 30 45 60 38 25 5 160 50 5 w 16 75 30 45 60 25 23 20 160 50 5 w 16 81 30 45 60 38 21 20 160 50 5 w 16 77 30 52 60 25 25 20 160 50 5 w 16 81 30 48 60 25 25 25 160 50 5 w 16 79 30 48 60 20 20 25 160 50 5 w 16 75

Looking at the results of Table 2, it can be seen that the yield is reduced when using potassium cyanide (Potassium cyanide) instead of sodium cyanide.

Add 48 g of H ₂ O to the reaction vessel, add 30 g of glycine (glycine), and then stir for 10 minutes. Then, 34 g of 37% (w / w) formaldehyde (30 g) at 25 ° C. under N ₂ purge for 30 minutes Was added dropwise and reacted at 60 ° C. for 1 hour to obtain 2- (hydroxymethylamino) acetic acid. (Step 1)

After cooling the 2- (hydroxymethylamino) acetic acid to 20 ° C. and slowly adding 20 g of sulfuric acid (H ₂ SO ₄ ) to pH 4-5 and stirring at room temperature for 10 minutes, 25 g of sodium cyanide was added. The solution was added dropwise at 15 ° C. and reacted at 50 ° C. for 1 hour to obtain 2- (cyanomethylamino) acetic acid. (Step 2)

After reacting 20 g of sulfuric acid (H ₂ SO ₄ ) with 140 g of H ₂ O for 30 minutes, it was added dropwise to the 2- (cyanomethylamino) acetic acid at 20 ° C., adjusted to pH 1˜2.5, and stirred at 40 ° C. for 5 hours to form Iminodiacetic. acid was obtained. (Step 3)

10 g of methanol at 5 ° C. was purified to the Iminodiacetic acid. (Step 4)

[Experimental Example 3]

In order to determine the purity of the iminodiacetic acid synthesized in Example 1 was analyzed using Liquid Chromatography (LC), it is shown in FIG. Looking at the results of Figure 2, it can be seen that the purity of the imino diacetic acid synthesized in Example 1 is 99.95%.

[Experimental Example 4]

In order to determine the heavy metal content of the iminodiacetic acid synthesized in Example 1 using an ICP-OES equipment is shown in Table 3.

division Example 1 (ppm) Reference value (ppm) Fe 3 5 Pb One One Ca 3 5 Cl 500 1200 Na 500 1500 K One One

Looking at the results of Table 3, it can be seen that the iminodiacetic acid (Iminodiacetic acid) synthesized in Example 1 contains a heavy metal below the reference value.

[Experimental Example 5]

Iminodiacetic acid synthesized in Example 1 was analyzed using IR, and the results are shown in FIG. 4.

As compared with the peak of Iminodiacetic acid (IDA) -reference shown in FIG. 3, it can be seen that the iminodiacetic acid synthesized in Example 1 has not detected any foreign substances other than the sample.

Experimental Example 6

Iminodiacetic acid synthesized in Example 1 was analyzed using Proton NMR, and the results are shown in FIG. 6.

As compared with the peak of Iminodiacetic acid (IDA) -STD shown in FIG. 5, it can be seen that the iminodiacetic acid synthesized in Example 1 was not detected in the foreign body other than the sample.

Claims (4)

60 to 65 parts by weight of glycine (Glycine) was added to 100 parts by weight of H ₂ O, followed by stirring for 10 minutes. Then, 70 to 75 parts by weight of 37% (w / w) formaldehyde was added dropwise thereto at 60 ° C. for 1 hour. Reacting to obtain 2- (hydroxymethylamino) acetic acid (step 1);
After stirring by adding 15-20 parts by weight of sulfuric acid (H ₂ SO ₄ ) to 100 parts by weight of 2- (hydroxymethylamino) acetic acid, 20-25 parts by weight of sodium cyanide was added dropwise and reacted at 50 ° C. for 1 hour. To obtain 2- (cyanomethylamino) acetic acid (step 2);
After adding 85 to 90 parts by weight of H ₂ O and 10 to 15 parts by weight of sulfuric acid (H ₂ SO ₄ ) to 100 parts by weight of 2- (cyanomethylamino) acetic acid, the mixture was stirred at 40 ° C. for 5 hours to obtain Iminodiacetic acid. Step (step 3); And
Purifying by adding 2-7 parts by weight of methanol at 1-5 ° C. to 100 parts by weight of Iminodiacetic acid (step 4);
Method for synthesizing iminodiacetic acid (Iminodiacetic acid) comprising a.
2. The method according to claim 1, wherein, in step 1,
The 37% (w / w) formaldehyde (Formaldehyde) is a method for synthesizing iminodiacetic acid (Iminodiacetic acid), characterized in that dropping for 30 minutes at 25 ℃ under N ₂ Purge.
The method of claim 1, wherein in step 2,
After cooling the 2- (hydroxymethylamino) acetic acid to 20 ° C. and adding sulfuric acid (H ₂ SO ₄ ) to adjust the pH to 4-5 and stirring at room temperature for 10 minutes, sodium cyanide is 10-25 A method for synthesizing iminodiacetic acid, which is added dropwise at ℃.
The method of claim 1, wherein in step 3,
After reacting sulfuric acid (H ₂ SO ₄ ) with H ₂ O for 30 minutes, the mixture is added dropwise to the 2- (cyanomethylamino) acetic acid at 20 ° C. to adjust the pH to 1 to 2.5. Method of synthesis).

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