CN112251757B

CN112251757B - Protective water and preparation method thereof

Info

Publication number: CN112251757B
Application number: CN202010970763.4A
Authority: CN
Inventors: 郑建国; 罗小平
Original assignee: Shenzhen Chonghui Surface Technology Development Co ltd
Current assignee: Chonghui semiconductor (Shenzhen) Co.,Ltd.
Priority date: 2020-09-15
Filing date: 2020-09-15
Publication date: 2021-09-14
Anticipated expiration: 2040-09-15
Also published as: CN112251757A

Abstract

The application relates to the field of electro-silvering treatment agents, and particularly discloses protective water and a preparation method thereof. The protective water comprises the following components in parts by mass: 1-10 parts of inorganic medium-strong acid; 1-10 parts of organic phosphonic acid scale inhibitor; 0.11-2 parts of triazole compounds; 0.5-0.9 part of sodium hydroxide; 1-10 parts of thiourea; the total mass portion of the protective water is 100 portions, and the balance is water; the preparation method comprises the following steps: and uniformly mixing all the components of the protective water to obtain the protective water. The protective water can be used for cleaning silver-plated products, and has the advantages of better removing alkaline residues of the silver-plated products and simultaneously being beneficial to better protecting the silver plating layer on the surfaces of the silver-plated products; in addition, the preparation method has the advantages of simple and convenient preparation and contribution to industrial production.

Description

Protective water and preparation method thereof

Technical Field

The application relates to the field of electro-silvering treatment agents, in particular to protective water and a preparation method thereof.

Background

At present, the silver electroplating process is widely applied to the manufacturing industries of electric appliances, instruments, lighting appliances and the like, and has extremely important significance for the life of people.

After the LED is plated with silver, an alkaline electrolytic cleaning process is often added to thoroughly prevent the plating layer from remaining other organic substances. If the silver coating is not subjected to alkaline electrolytic cleaning, the silver coating becomes fog white at the temperature of about 180 ℃ during injection molding, so that the product is scrapped. However, the silver-plated product is cleaned by alkaline silver plating, residues are left, and the residues are not easy to clean completely, especially in low temperature, the cleaning of the alkaline residues is troublesome, and the cleaning of the alkaline residues is incomplete, so that subsequent dispensing, wire bonding, die bonding and the like of the silver-plated product are easily influenced.

At present, silver-plated products are cleaned by deionized water after alkaline silver-plating cleaning, but the deionized water is difficult to completely remove alkaline residues, and a cleaning solution capable of effectively cleaning the alkaline residues is not found for a while.

In view of the above-mentioned related art, the inventors considered that there was a defect that alkaline residues on silver-plated products were difficult to clean after the silver-plated products were subjected to alkaline silver-plating cleaning.

Disclosure of Invention

In order to clean alkaline residues on silver-plated products more thoroughly, the application provides protective water and a preparation method thereof.

In a first aspect, the present application provides a protective water, which adopts the following technical scheme:

the protective water comprises the following components in parts by mass:

1-10 parts of inorganic medium-strong acid;

1-10 parts of organic phosphonic acid scale inhibitor;

0.11-2 parts of triazole compounds;

0.5-0.9 part of sodium hydroxide;

1-10 parts of thiourea;

the total mass portion of the protective water is 100 portions, and the balance is water.

By adopting the technical scheme, the addition of the inorganic medium-strong acid is beneficial to more thoroughly cleaning the alkaline residues on the silver-plated products, meanwhile, the addition of the organic phosphonic acid scale inhibitor and the triazole compound is beneficial to better adjusting the acidity of the inorganic medium-strong acid, so that the inorganic medium-strong acid is beneficial to better cleaning the alkaline residues on the silver-plated products more thoroughly, the inorganic medium-strong acid is not easy to influence the silver plating layer of the silver-plated products, the silver-plated products are favorably cleaned, the silver plating layer of the silver-plated products is not easy to influence, and the subsequent dispensing and crystal fixing effects of the silver-plated products are better.

The sodium hydroxide and the thiourea are adopted to improve the triazole compound, so that the cleaning function of the protective water is favorably promoted, the alkaline residues on the silver-plated product are cleaned more easily and thoroughly, the corrosion inhibition of the acidity of the medium and strong acid is favorably realized, and the protective water is less likely to influence the silver plating layer of the silver-plated product.

Preferably, the inorganic medium-strong acid is one or more of phosphoric acid, sulfurous acid, oxalic acid, chromic acid, iodic acid, n-periodic acid, hydrofluoric acid, nitrous acid, carbonic acid, hypochlorous acid, hypoiodic acid, boric acid and metasilicic acid.

By adopting the technical scheme, the compounding of one or more acids is beneficial to better cooperative matching of inorganic medium and strong acid and other components, better adjustment of acidity of the protective water, more thorough cleaning of alkaline residues on silver-plated products by the protective water and better protection of silver-plated layers on the surfaces of the silver-plated products.

Preferably, the inorganic medium-strong acid is phosphoric acid.

By adopting the technical scheme, the phosphoric acid is selected as the inorganic medium-strong acid, so that the acidity of the protective water can be better adjusted, the protective water can more easily clean alkaline residues on silver-plated products thoroughly, and meanwhile, the protective water is not easy to influence the silver plating layer on the surfaces of the silver-plated products.

Preferably, the organic phosphonic acid scale inhibitor is one or more of hydroxyethylidene diphosphonic acid, aminotrimethylene phosphonic acid, hydroxyethylidene diphosphonic acid and hydroxyethylidene diphosphonic acid.

By adopting the technical scheme, one or more substances are compounded, so that the corrosion inhibition of the acidity of inorganic medium and strong acid is facilitated, the acidity of the protective water is more favorable for cleaning the surface of the silver-plated product, and the influence on the silver plating layer on the surface of the silver-plated product is less likely to occur.

Preferably, the organic phosphonic acid scale inhibitor is hydroxyethylidene diphosphonic acid.

By adopting the technical scheme, the hydroxyethylidene diphosphonic acid is adopted as the organic phosphonic acid scale inhibitor, so that the scale inhibitor is favorable for better inhibiting the acidity of inorganic medium and strong acid, the protective water can more easily clean the alkaline residues of the silver-plated product, and the silver plating layer on the surface of the silver-plated product is less susceptible.

Preferably, the triazole compound is one or more of benzotriazole, mercaptotriazole and methylbenzotriazole.

By adopting the technical scheme and compounding one or more substances, the triazole compound is favorable for better slowly releasing the acidity of inorganic medium and strong acid, and the silver plating layer on the surface of the silver plating product is not easily influenced by the corrosion of the acid while the alkaline residues on the surface of the silver plating product are better cleaned by protective water.

Preferably, the triazole compound comprises the following components in parts by mass:

0.1-1 part of methylbenzotriazole;

0.01-1 part of benzotriazole.

By adopting the technical scheme, the synergistic cooperation of the methylbenzotriazole and the benzotriazole in a specific proportion is beneficial to better inhibiting the acidity of inorganic medium and strong acid by the triazole compounds, so that the alkaline residues of the silver-plated products can be cleaned more thoroughly by the protective water, and the silver-plated layers on the surfaces of the silver-plated products are not easily affected by the protective water.

Preferably, the composition comprises the following components in parts by mass:

1-10 parts of phosphoric acid;

1-10 parts of hydroxyethylidene diphosphonic acid;

0.1-1 part of methylbenzotriazole;

0.01-1 part of benzotriazole;

0.5-0.9 part of sodium hydroxide;

1-10 parts of thiourea;

By adopting the technical scheme, the phosphoric acid, the hydroxyethylidene diphosphonic acid, the methyl benzotriazole and the benzotriazole in a specific proportion are matched with each other in a synergistic manner, so that the acidity of the protective water can be better adjusted, the alkaline residues of the silver-plated product can be more easily cleaned more thoroughly, the silver-plated layer on the surface of the silver-plated product can be more difficultly corroded by the protective water, and the silver-plated layer of the silver-plated product can be better protected.

In a second aspect, the present application provides a method for preparing protective water, which adopts the following technical scheme:

a preparation method of the protective water comprises the step of uniformly mixing all the components of the protective water to obtain the protective water.

By adopting the technical scheme, the protective water can be prepared by uniformly mixing the components, the preparation operation is simple, convenient and quick, and the industrial production of the protective water is facilitated.

In summary, the present application has the following beneficial effects:

1. the addition of the inorganic medium-strong acid is favorable for more thoroughly cleaning the alkaline residues on the silver-plated products, and meanwhile, the addition of the organic phosphonic acid scale inhibitor and the triazole compound is also favorable for better adjusting the acidity of the inorganic medium-strong acid, so that the inorganic medium-strong acid is not easy to influence the silver plating layer of the silver-plated products while the inorganic medium-strong acid is favorable for better cleaning the alkaline residues on the silver-plated products more thoroughly, the inorganic medium-strong acid is not easy to influence the silver plating layer of the silver-plated products while the silver-plated products are favorably cleaned, and the subsequent dispensing and die bonding effects of the silver-plated products are also better.

2. The sodium hydroxide and the sulfuric acid are adopted to improve the triazole compound, so that the cleaning function of the protective water is favorably promoted, the alkaline residues on the silver-plated product are cleaned more easily and thoroughly, the corrosion inhibition of the acidity of the medium and strong acid is favorably realized, and the protective water is less likely to influence the silver plating layer of the silver-plated product.

Detailed Description

The present application will be described in further detail with reference to examples.

In the following examples, hydroxyethylidene diphosphonic acid of product number 1 from Germany chemical Co., Ltd, Guangzhou was used.

In the following examples, hydroxyethylidene diphosphonic acid from Sanchang chemical Co., Ltd, Guangzhou under the trade name SC19120409 was used.

In the following examples, benzotriazole of product number 1 from Shiyang Longxing Wei trade company, is used.

In the following examples, methylbenzotriazole of 9957, a trade name of kunshan sandian biotechnology limited, is used as methylbenzotriazole.

In the following examples, 3-mercapto-1, 2, 4-triazole, having a product number of 3179-31-5, available from Wuhan-Prov Biotech Ltd, was used as the mercaptotriazole.

In the following examples, the thiourea used was 62 to 56 to 6, the product number of Zhengzhou Jinfengda chemical products Co., Ltd.

Example 1

The embodiment of the application discloses protective water, which comprises the following components:

sulfurous acid; hydroxyethylidene diphosphonic acid; benzotriazole; sodium hydroxide; thiourea; deionized water.

The embodiment of the application also discloses a preparation method of the protective water, which comprises the following steps:

adding sulfurous acid, hydroxyethylidene diphosphonic acid, benzotriazole, sodium hydroxide, thiourea and deionized water into a stirring kettle, stirring at the normal temperature at the rotating speed of 350r/min, and stirring and mixing uniformly to obtain the protective water.

Wherein, the components and the dosage of the protective water are shown in table 1, and the dosage unit of each component in table 1 is kg.

Example 2

The difference from example 1 is that: the components and the amounts of the protective water are shown in Table 1.

Example 3

Example 4

TABLE 1

Example 5

The difference from example 4 is that: equal amounts of phosphoric acid were used instead of sulfurous acid.

Example 6

The difference from example 4 is that: the hydroxyethylidene diphosphonic acid is replaced by an equal amount of hydroxyethylidene diphosphonic acid.

Example 7

The difference from example 4 is that: the benzotriazole is replaced by equivalent methylbenzotriazole.

Examples 8 to 14

The difference from example 4 is that:

the triazole compound is prepared by uniformly mixing benzotriazole and methyl benzotriazole;

wherein, the components and the dosage of the protective water are shown in table 2, and the dosage unit of each component in table 2 is kg.

TABLE 2

Examples 15 to 18

The difference from example 4 is that: the components and the amounts of the protective water are shown in Table 3, and the unit of the amount of each component in Table 3 is kg.

TABLE 3

	Example 15	Example 16	Example 17	Example 18
					Phosphoric acid	1	5.5	10	8
Hydroxyethylidene diphosphonic acid	10	1	5.5	4
					Benzotriazole	0.01	0.5	1	0.3
Methyl benzotriazole	1	0.55	0.1	0.6
					Sodium hydroxide	0.7	0.9	0.5	0.8
Thiourea	5.5	10	1	5
					Deionized water	81.79	81.55	81.9	81.3

Comparative example 1

The difference from example 4 is that: equal amount of deionized water is used to replace the hydroxyethylidene diphosphonic acid and the benzotriazole.

Comparative example 2

The difference from example 4 is that: equal amounts of deionized water were substituted for hydroxyethylidenediphosphonic acid.

Comparative example 3

The difference from example 4 is that: the benzotriazole was replaced by an equal amount of deionized water.

Comparative example 4

The difference from example 4 is that: equal amounts of deionized water were used in place of sodium hydroxide and thiourea.

Comparative example 5

The difference from example 4 is that: equal amounts of deionized water were used in place of sodium hydroxide.

Comparative example 6

The difference from example 4 is that: equal amounts of deionized water were substituted for the thiourea.

Experiment 1

Taking 100g of the protective water prepared in the above examples and comparative examples, respectively adding 10g of silver strips into the protective water, soaking for 2min, taking out and drying the silver strips, weighing again, recording the mass (g) of the soaked silver strips, and soaking 10g of the silver strips into 100g of deionized water for 2min as a blank group.

Experiment 2

Taking 100g of the protective water prepared in the above embodiment and comparative example, respectively soaking the LED silver-plated products in the protective water for 1min, soaking the LED silver-plated products in deionized water for 1min as a blank group, taking out and drying the LED silver-plated products after soaking, respectively soaking the dried LED silver-plated products in 100g of deionized water for 10min, and then respectively detecting the pH value of the deionized water in which the dried LED silver-plated products are soaked.

Experiment 3

Taking 100g of the protective water prepared in the embodiment and the comparative proportion, respectively putting the LED silver-plated products into the protective water for soaking for 1min, putting the LED silver-plated products into deionized water for soaking for 1min as a blank group, taking out and drying the LED silver-plated products after soaking is finished, putting the LED silver-plated products into an automatic dispenser for dispensing, putting the dispensed LED silver-plated products into a die bonder for die bonding, carrying out die bonding operation after die bonding and baking are finished, carrying out a wafer thrust test by adopting a Dage 4000 thrust tester, and detecting the adhesion degree (g) of the wafer and the silver adhesive at the temperature of 150 ℃. Wherein the larger the pushing force is, the better the adhesion between the wafer and the silver adhesive is.

In the experiment, the LED silver-plated product adopts an LED silver-plated product with a product number of 2006 of Honghao hardware electronics limited company in Huizhou city; the automatic glue dispenser adopts a full-automatic glue dispenser with model number HZ-491 of Shenzhen Hongshanautomation equipment Limited; the die bonder adopts a full-automatic planar LED die bonder with model number AG5200 of Shenzhen Wei Tianxing semiconductor equipment Limited company; the Dane 4000 push-pull force tester is a model 4000 Dane 4000 push-pull force tester manufactured by Chuangjie science and technology (hong Kong) Co.

The data from the above experiments are shown in Table 4.

TABLE 4

According to the comparison of the data of the example 4 and the comparative example 1 in the table 4, the comparative example 1 is less added with the organic phosphonic acid type scale inhibitor and the triazole compound than the example 4, the loss amount of the silver strips after soaking of the example 4 is far less than that of the comparative example 1, and the pH value of the deionized water soaked with the silver-plated product of the example 4 is far closer to neutral than that of the example 1, which shows that the silver-plated layer on the surface of the silver-plated product is easily affected by adding the inorganic medium strong acid alone, and even the silver-plated product cannot be subjected to the operations of dispensing, crystal fixing and the like subsequently.

According to the comparison of the data of the example 4 and the comparative examples 2-3 in the table 4, the comparative example 2 and the comparative example 3 are respectively less added with the organic phosphonic acid scale inhibitor and the triazole compound than the example 4, while the loss amount of the silver strips after soaking and the pH value of the deionized water soaked in the silver-plated product of the comparative examples 2-3 are similar to those of the comparative example 1, which shows that only when the organic phosphonic acid scale inhibitor and the triazole compound jointly inhibit the acidity of the inorganic medium strong acid, the influence of the inorganic medium strong acid on the silver plating layer of the silver-plated product can be better reduced, and any substance synergistic effect is lacked, so that the silver plating layer of the silver-plated product is easily greatly influenced, and even the silver-plated product cannot be subjected to subsequent operations such as dispensing, crystal fixing and the like.

Comparing the data of example 4 and comparative examples 4-6 in table 4, the comparative example 4 has less sodium hydroxide and thiourea than example 4, the comparative examples 5-6 have less sodium hydroxide and thiourea than example 4, respectively, the loss amount of the silver strips after soaking of example 4 is less than that of comparative examples 4-6 to a certain extent, the pH value of the deionized water after soaking of the silver-plated product of example 4 is greater than that of comparative examples 4-6 to a certain extent, the loss amount of the silver strips after soaking of examples 5-6 and the pH value of the deionized water after soaking of the silver-plated product are similar to those of comparative example 4, which shows that only by using the synergistic combination of sodium hydroxide and thiourea together, the triazole compound can be improved better, and any substance is absent, the influence on the silver-plated layer of the silver-plated product is easily increased, even the silver coating of the silver-coated product is difficult to realize subsequent operations such as dispensing, die bonding and the like.

According to the comparison of the data of the examples 4 to 6 in the table 4, the kind of the inorganic medium strong acid in the example 5 is different from that of the example 4, the kind of the organic phosphonic acid type scale inhibitor in the example 6 is different from that of the example 4, while the pH value of the deionized water of the LED silver-plated product soaked and dried in the examples 5 to 6 is closer to neutral to a certain extent, and the adhesion degree of the examples 5 to 6 is greater than that of the example 4, which shows that the acidity of the protection water is favorably adjusted by adopting phosphoric acid as the inorganic medium strong acid or hydroxyl ethylidene diphosphonic acid as the organic phosphonic acid type scale inhibitor, the protection water is favorably used for better cleaning the alkaline residues on the silver-plated product and better protecting the silver-plated layer on the surface of the silver-plated product, and the subsequent dispensing of the silver-plated product is better in crystal fixing effect.

According to the comparison of the data of example 4 and examples 7 to 14 in table 4, the triazole compound of example 4 is benzotriazole, the triazole compound of example 7 is methylbenzotriazole, the triazole compounds of examples 8 to 10 are a mixture of methylbenzotriazole and benzotriazole in a certain proportion range, the triazole compounds of examples 11 to 12 are a mixture of methylbenzotriazole and benzotriazole in a certain proportion range, examples 13 to 14 adopt mercaptotriazole to replace benzotriazole and methylbenzotriazole respectively on the basis of example 10, while the pH value of the deionized water of the dried LED silver-plated products of examples 8 to 10 is lower than that of examples 11 to 12 in a certain degree, is lower than that of examples 13 to 14 in example 7 and example 4 in examples 13 to 10, and the adhesion degree of the embodiments 8 to 10 is greater than that of the embodiments 11 to 12, is greater than that of the embodiments 13 to 14, is greater than that of the embodiments 7 and 4, and the data of the embodiments 4, 7 and 13 to 14 are similar, which indicates that the triazole compound is formed by mutually cooperating benzotriazole and methyl benzotriazole in a specific proportion, so that the corrosion inhibition of the inorganic medium and strong acid is better facilitated, the prepared protective water is beneficial to better cleaning the alkaline residues on the surface of the silver-plated product and better protecting the silver-plated layer on the surface of the silver-plated product, the subsequent dispensing and crystal fixation effects of the silver-plated product are better, any substance is lacked or any proportion of the protective water is changed, and the cleaning performance and the protective performance of the protective water are easily influenced.

According to the comparison of the data of examples 5 to 6, examples 8 to 10 and examples 15 to 18 in table 4, in example 5, phosphoric acid alone is used as the inorganic medium-strong acid, in example 6, hydroxyethylidene diphosphonic acid alone is used as the organic phosphonic acid type scale inhibitor, in examples 8 to 10, a mixture of methylbenzotriazole and benzotriazol within a specific proportion range is used as the triazole compound, in examples 15 to 18, phosphoric acid, hydroxyethylidene diphosphonic acid, benzotriazol and methylbenzotriazole are used together to cooperate synergistically, while the pH value of the deionized water of the LED silver-plated products soaked and dried in examples 15 to 18 is lower than that of examples 5 to 6 and examples 8 to 10 to a certain extent, and the adhesion degree of examples 15 to 18 is higher than that of examples 5 to 6 and examples 8 to 10 to a certain extent, the method is characterized in that phosphoric acid, hydroxyethylidene diphosphonic acid, benzotriazole and methyl benzotriazole are simultaneously adopted to cooperate with each other, so that the acidity of the protective water can be better adjusted, the protective water can be better used for cleaning alkaline residues of silver-plated products, and simultaneously the silver-plated layers on the surfaces of the silver-plated products can be better protected, and the subsequent dispensing and die-bonding effects of the silver-plated products are better.

According to the data of the embodiments 1 to 18 in the table 4, alkaline residues on the surface of the silver-plated product can be completely removed only by soaking the silver-plated product in the protective water for 1min, and in order to improve the efficiency, the speed of the existing electroplating line is increased to 10-20 m/min, so that the protective water in the electroplating line can meet the production requirement, the silver-plated product can be cleaned only by passing the electroplated silver-plated product through a cleaning tank filled with the protective water, the production cost is favorably reduced under the condition of not influencing the production efficiency, the discharge amount of electroplating wastewater is favorably reduced, and the electroplating line is favorable for energy conservation and environmental protection.

The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims

1. A protective water, characterized in that: the paint comprises the following components in parts by mass:

1-10 parts of inorganic medium-strong acid;

1-10 parts of organic phosphonic acid scale inhibitor;

0.11-2 parts of triazole compounds;

0.5-0.9 part of sodium hydroxide;

1-10 parts of thiourea;

the total mass portion of the protective water is 100 parts, and the balance is water;

the triazole compound comprises the following components in parts by mass:

0.1-1 part of methylbenzotriazole;

0.01-1 part of benzotriazole.

2. The protective water according to claim 1, wherein: the inorganic medium and strong acid is one or more of phosphoric acid, sulfurous acid, chromic acid, iodic acid, normal periodic acid, hydrofluoric acid and nitrous acid.

3. The protective water according to claim 2, characterized in that: the inorganic medium-strong acid is phosphoric acid.

4. The protective water according to any one of claims 1 to 3, wherein: the organic phosphonic acid scale inhibitor is one or more of hydroxyethylidene diphosphonic acid, aminotrimethylene phosphonic acid and hydroxyethylidene diphosphonic acid.

5. The protective water according to claim 4, wherein: the organic phosphonic acid scale inhibitor is hydroxyethylidene diphosphonic acid.

6. The protective water according to claim 1, wherein: the paint comprises the following components in parts by mass:

1-10 parts of phosphoric acid;

1-10 parts of hydroxyethylidene diphosphonic acid;

0.1-1 part of methylbenzotriazole;

0.01-1 part of benzotriazole;

0.5-0.9 part of sodium hydroxide;

1-10 parts of thiourea;

7. A method for producing the protective water according to any one of claims 1 to 6, characterized in that: and uniformly mixing all the components of the protective water to obtain the protective water.