阅读说明：本技术 一种适用于线路板上的深度清洗剂及其使用方法 (Deep cleaning agent suitable for circuit board and use method thereof ) 是由 陈钜 韦金宇 夏海 李初荣 于 2021-09-07 设计创作，主要内容包括：本发明提供了一种适用于线路板上的深度清洗剂,由以下浓度组分组成：0.05-4g/L的表面活性剂、5-150g/L的无机酸、1-30g/L的有机酸、1-8000ppm的小分子醇类和1-80ppm的含氮铜面保护剂；所述表面活性剂为醇醚羧酸盐,其结构式为R-(OCH-(2)CH-(2))-(n)OCH-(2)COOM(H),其中,R为C12-C14的脂肪醇,n为3或5,M为金属离子。采用本申请的清洗剂清洗铜面后,油污和印上去的手印均能很好地洗去；铜面残留的O小于0.3％,残留的C小于0.9％,说明本发明的适用于线路板上的深度清洗剂。清洗完后,铜面不会立刻氧化,持续抗氧化时间可达到4-8小时。(The invention provides a deep cleaning agent suitable for a circuit board, which consists of the following components in concentration: 0.05-4g/L of surfactant, 5-150g/L of inorganic acid, 1-30g/L of organic acid, 1-8000ppm of micromolecule alcohol and 1-80ppm of nitrogenous copper surface protective agent; the surfactant is alcohol ether carboxylate with a structural formula of R- (OCH) 2 CH 2 ) n OCH 2 COOM (H), wherein R is C12-C14 fatty alcohol, n is 3 or 5, and M is metal ion. After the cleaning agent is used for cleaning the copper surface, oil stains and fingerprints printed on the copper surface can be well removed; the residual O on the copper surface is less than 0.3 percent, and the residual C is less than 0.9 percent, which indicates that the deep cleaning agent is suitable for the circuit board. After the cleaning, the copper surface is not oxidized immediately, and the continuous oxidation resistance time can reach 4 to 8 hours.)

1. The deep cleaning agent suitable for the circuit board is characterized by comprising the following components in concentration: 0.05-4g/L of surfactant, 5-150g/L of inorganic acid, 1-30g/L of organic acid, 1-8000ppm of micromolecule alcohol and 1-80ppm of nitrogenous copper surface protective agent; the surfactant is alcohol ether carboxylate with a structural formula of R- (OCH)₂CH₂)_nOCH₂COOM (H), wherein R is C12-C14 fatty alcohol, n is 3 or 5, and M is metal ion.

2. The deep cleaning agent suitable for the circuit board as claimed in claim 1, wherein the nitrogen-containing copper surface protective agent is one of 1-phenyl-4-methylimidazole, 2-amino-5-mercapto-1, 3, 4-thiadiazole and 1-p-toluene-4-methylimidazole.

3. The deep cleaning agent for circuit boards as claimed in claim 1, wherein the small molecular alcohol has 1-4 carbon atoms.

4. The deep cleaning agent for circuit boards as claimed in claim 3, wherein the small molecular alcohol is one of ethylene glycol and isopropanol.

5. The deep cleaning agent for circuit boards as claimed in claim 1, wherein the organic acid is one of sulfamic acid, citric acid and glycolic acid.

6. The deep cleaning agent for circuit boards as claimed in claim 1, wherein the inorganic acid is sulfuric acid.

7. The deep cleaning agent for circuit boards as claimed in any one of claims 1 to 6, wherein the concentration of the surfactant is 0.1-2g/L, the concentration of the inorganic acid is 30-120g/L, the concentration of the organic acid is 5-20g/L, the concentration of the small molecular alcohol is 1000-6000ppm, and the concentration of the nitrogen-containing copper surface protective agent is 5-50 ppm.

8. The deep cleaning agent for circuit boards as claimed in claim 7, wherein the concentration of the surfactant is 0.2-1g/L, the concentration of the inorganic acid is 50-100g/L, the concentration of the organic acid is 10-15g/L, the concentration of the small molecular alcohol is 3000-5000ppm, and the concentration of the nitrogen-containing copper surface protective agent is 8-20 ppm.

9. The use method of the deep cleaning agent suitable for the circuit board as claimed in any one of claims 1 to 8, wherein the spraying is carried out on the copper surface of the PCB at the temperature of 25-35 ℃, the linear speed is 3-5m/s, and the time is 30-45 s.

10. The use method of the deep cleaning agent suitable for the circuit board as claimed in claim 9, wherein after the spraying is completed, the PCB is washed by overflowing water and then dried at 70-90 ℃.

Technical Field

The invention relates to the technical field of fine circuit board processing, in particular to a deep cleaning agent suitable for a circuit board and a using method thereof.

Background

The cleaning of the circuit board mainly removes surface dirt on the copper surface. After the plate passes through each process, finger prints, dust, oxide layers, oil stains and the like can be inevitably left on the plate surface, and the defects that the circuit board is opened and short-circuited and the like are easily caused if the pollutants are not cleaned. In order to clean the copper surface and ensure that the surface of the copper plate is kept clean before the steps of dry film pasting, pattern electroplating, tin spraying, gold deposition and the like, the surface of the copper plate is generally cleaned (deoiled) before the next process. At present, most of degreasing agents used for cleaning circuit boards are acid degreasing agents based on surfactants, organic acids, inorganic acids and other auxiliaries.

The degreasing agent used in the existing circuit board manufacturing process can not remove some circuit boards which are subjected to deep oxidation, and generally, the circuit boards subjected to deep oxidation need extra steps of grinding boards, sandblasting and the like, so that the time and the production cost are increased. Although the degreasing agents in patent nos. CN113136581A and CN111117793A can solve the problem of deep oxidation, the total phosphorus (introduced by N- (6-aminohexyl) -1, 6-hexamethylenediamine pentamethylenephosphonic acid) in the system liquid medicine of CN113136581A causes ecological pollution in the subsequent wastewater discharge, and the ferric iron compound in CN111117793A is relatively difficult to treat in the subsequent wastewater treatment. Although the degreasing agent in patent CN104388961A can solve the problem of deep oxidation and has no problem of sewage treatment, the degreasing agent needs 2-5 min of treatment time during cleaning and is not suitable for the requirements of circuit board production (the treatment time in the degreasing process is 30-45s generally).

Disclosure of Invention

The technical problem to be solved by the invention is as follows: the copper surface cleaning agent is suitable for the production process of circuit boards, can solve the problem of deep oxidation of copper layers of the circuit boards, and is low in sewage treatment difficulty after application.

In order to solve the technical problems, the invention adopts the technical scheme that:

a deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.05-4g/L of surfactant, 5-150g/L of inorganic acid, 1-30g/L of organic acid, 1-8000ppm of micromolecule alcohol and 1-80ppm of nitrogenous copper surface protective agent; the surfactant is alcohol ether carboxylate with a structural formula of R- (OCH)₂CH₂)_nOCH₂COOM (H), wherein R is C12-C14 fatty alcohol, n is 3 or 5, and M is metal ion.

Further, the nitrogen-containing copper surface protective agent is one of 1-phenyl-4-methylimidazole, 2-amino-5-mercapto-1, 3, 4-thiadiazole and 1-p-toluene-4-methylimidazole.

Further, the carbon number of the small molecule alcohol is 1-4.

Further, the small molecular alcohol is one of ethylene glycol and isopropanol.

Further, the organic acid is one of sulfamic acid, citric acid and glycolic acid.

Further, the inorganic acid is sulfuric acid.

Furthermore, the concentration of the surfactant is 0.1-2g/L, the concentration of the inorganic acid is 30-120g/L, the concentration of the organic acid is 5-20g/L, the concentration of the small molecular alcohol is 1000-6000ppm, and the concentration of the nitrogen-containing copper surface protective agent is 5-50 ppm.

Further, the concentration of the surfactant is 0.2-1g/L, the concentration of the inorganic acid is 50-100g/L, the concentration of the organic acid is 10-15g/L, the concentration of the small molecular alcohol is 3000-5000ppm, and the concentration of the nitrogen-containing copper surface protective agent is 8-20 ppm.

The application method of the deep cleaning agent suitable for the circuit board comprises the step of spraying the copper surface of the PCB at the temperature of 25-35 ℃, wherein the linear speed is 3-5m/s, and the time is 30-45 s.

Further, after spraying is finished, overflowing and washing, and then drying the PCB at the temperature of 70-90 ℃.

The invention has the beneficial effects that:

after the molecules of the surfactant alcohol ether carboxylate are dissolved in water, the repulsion force between the lipophilic group and the water molecules exists, and the trend of the force chart leaving the aqueous solution promotes the molecules to move to the interface of the water, so that the oriented arrangement is generated. Thus, the lipophilic group points to the outside of the water surface, and the hydrophilic group points to the inside of the water surface, so that water molecules on the interface between water and air or between water and other substances are replaced by surfactant molecules, the tension of the water surface is further reduced rapidly, conditions are created for cleaning and removing the grease on the copper surface by using the aqueous solution with the surfactant, and the grease can form oil drops in the aqueous solution and can be effectively removed.

Organic acid and inorganic acid in the system are used as auxiliary agents to enhance the decontamination capability of the surfactant, and can effectively remove copper surface oxidation, and the micromolecular alcohols have excellent diffusivity and wettability, so that the cleaning agent can rapidly infiltrate the copper surface, and the cleaning efficiency is improved.

The nitrogen-containing copper surface-protecting agent is composed of a polar group centered on an N atom having a large electronegativity and a nonpolar group composed of C, N atoms. Therefore, the active center of the nitrogenous copper surface protective agent has strong adsorption effect on copper, can form a stable complex with the copper surface, and is easy to form hydrogen bonds between molecules or in molecules to thicken an adsorption layer, thereby preventing hydrogen ions from approaching the copper surface. The polar group is adsorbed on the surface of copper, so that the structure of a double electric layer is changed, the activation energy of etching reaction is improved, and the etching rate is slowed down; the nonpolar groups are directionally arranged away from the copper surface to form a protective layer, which prevents the transfer of substances that can undergo etching reactions, further reducing the etching rate. The protective film has obvious effect on the oxidation resistance of the board surface, and can ensure that the copper surface can not be oxidized within 1-3 hours (even 4-8 hours) after being cleaned.

The condition and the method of using the cleaning agent are similar to those of the degreasing agent commonly used at the present stage, a production line does not need to be changed for circuit board enterprises, the cleaning agent can effectively remove fingerprints, ash layers, deep oxides and oil stains on a circuit board, a layer of protective film can be formed on a copper surface, the cleaned copper surface can be effectively prevented from being oxidized within 4-8 hours, the protective film can be completely removed through a common acid washing process, and no residue is left on the copper surface.

In conclusion, after the cleaning agent is used for cleaning the copper surface, oil stains and printed fingerprints can be well removed; the residual O on the copper surface is less than 0.3 percent, and the residual C is less than 0.9 percent, which indicates that the deep cleaning agent is suitable for the circuit board. After the cleaning, the copper surface can not be oxidized immediately, and the continuous oxidation resistance time is 1 to 3 hours, even can reach 4 to 8 hours.

Drawings

The detailed structure of the invention is described in detail below with reference to the accompanying drawings

FIG. 1 is a SEM image of the copper surface of a test board cleaned with the cleaning agent of example 1 of the present invention;

FIG. 2 is a SEM image of the copper surface of a test board cleaned by the cleaning agent of example 2 of the present invention;

FIG. 3 is a SEM image of the copper surface of a test board cleaned by using the cleaning agent of example 3 of the present invention;

FIG. 4 is a SEM image of the copper surface of a test board cleaned by the cleaning agent of example 4 of the present invention;

FIG. 5 is a SEM image of the copper surface of a test board cleaned with the cleaning agent of example 5 of the present invention;

FIG. 6 is a SEM image of the copper surface of a test board cleaned with the cleaning agent of example 6 of the present invention;

FIG. 7 is a SEM image of the copper surface of a test board cleaned with the cleaning agent of example 7 of the present invention;

FIG. 8 is a SEM image of the copper surface of a test board cleaned with the cleaning agent of example 8 of the present invention;

FIG. 9 is a SEM image of the copper surface of a test board cleaned with the cleaning agent of example 9 of the present invention;

FIG. 10 is a SEM image of the copper side of a test board cleaned with the cleaning agent of example 10 of the present invention;

FIG. 11 is a SEM image of the copper surface of a test board cleaned with the cleaning agent of example 11 of the present invention;

FIG. 12 is a SEM image of the copper side of a test board cleaned with the cleaning agent of example 12 of the present invention;

FIG. 13 is a SEM image of the copper side of a test plate after being cleaned with the cleaning agent of example 13 of the present invention;

FIG. 14 is a SEM image of the copper side of a test board cleaned with the cleaning agent of example 14 of the present invention;

FIG. 15 is a SEM image of the copper side of a test plate after being cleaned with the cleaning agent of example 15 of the present invention;

FIG. 16 is a SEM image of the copper side of a test plate after being cleaned with the cleaning agent of example 16 of the present invention;

FIG. 17 is a SEM image of the copper side of a test plate after being cleaned with the cleaning agent of example 17 of the present invention;

FIG. 18 is a SEM image of the copper side of a test plate after being cleaned with the cleaning agent of example 18 of the present invention;

FIG. 19 is a SEM image of the copper side of a test plate after being cleaned with the cleaning agent of example 19 of the present invention;

FIG. 20 is a SEM image of the copper side of a test plate after being cleaned with the cleaning agent of example 20 of the present invention;

FIG. 21 is a SEM image of the copper side of a test plate after being cleaned with the cleaning agent of example 21 of the present invention;

FIG. 22 is a SEM image of the copper side of a test plate cleaned with the cleaning agent of example 22 of the present invention;

FIG. 23 is a SEM image of the copper side of a test plate after being cleaned with the cleaning agent of example 23 of the present invention;

FIG. 24 is a SEM image of the copper side of a test plate after being cleaned with the cleaning agent of example 24 of the present invention;

FIG. 25 is a SEM image of the copper side of a test plate after being cleaned with the cleaning agent of example 25 of the present invention;

FIG. 26 is a SEM image of the copper surface of a test board cleaned with the cleaning agent of example 26;

FIG. 27 is a SEM image of the copper side of a test plate after being cleaned with the cleaning agent of example 27 of the present invention;

FIG. 28 is a SEM image of the copper side of a test plate after being cleaned with the cleaning agent of example 28 according to the invention;

FIG. 29 is a SEM image of the copper side of a test plate after being cleaned with the cleaning agent of example 29 of the present invention;

FIG. 30 is a SEM image of the copper side of a test plate after being cleaned with a cleaning agent in example 30 of the present invention;

FIG. 31 is a SEM image of the copper side of a test plate after being cleaned with the cleaning agent of example 31 of the present invention;

FIG. 32 is a SEM image of the copper side of a test plate after being cleaned with the cleaning agent of example 32 of the present invention;

FIG. 33 is a SEM image of the copper side of a test plate after being cleaned by using the cleaning agent in example 33 of the invention;

FIG. 34 is a SEM image of the copper side of a test plate after being cleaned with the cleaning agent of example 34 of the present invention;

FIG. 35 is a SEM image of the copper side of a test plate after being cleaned with the cleaning agent of example 35 of the present invention;

FIG. 36 is a SEM image of the copper side of a test plate after being cleaned with the cleaning agent of example 36 of the present invention;

FIG. 37 is a SEM image of the copper side of a test plate after being cleaned by using the cleaning agent of example 37 of the present invention;

FIG. 38 is a SEM image of the copper side of a test plate after being cleaned with the cleaning agent of example 38 of the invention;

FIG. 39 is a SEM image of the copper side of a test plate after being cleaned with the cleaning agent of example 39 of the present invention;

FIG. 40 is a SEM image of the copper side of a test plate after being cleaned with the cleaning agent of example 40 of the present invention;

FIG. 41 is a SEM image of the copper side of a test panel after cleaning with the cleaner of comparative example 1;

FIG. 42 is a SEM image of the copper side of a test panel after cleaning with the cleaner of comparative example 2;

FIG. 43 is a SEM image of the copper side of a test panel after cleaning with the cleaner of comparative example 3;

FIG. 44 is a SEM image of the copper side of a test panel after cleaning with the cleaner of comparative example 4;

FIG. 45 is a SEM image of the copper side of a test panel after cleaning with the cleaner of comparative example 5;

FIG. 46 is a SEM image of the copper side of a test panel after cleaning with the cleaner of comparative example 6;

FIG. 47 is a SEM image of the copper side of a test panel after cleaning with the cleaner of comparative example 7.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na (i.e. alcohol ether carboxylate, n ═ 3), 60g/L sulfuric acid, 12g/L sulfamic acid, 4500ppm ethylene glycol and 10ppm 1-phenyl-4-methylimidazole.

Example 2

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.1g/L AEC-3Na, 60g/L sulfuric acid, 12g/L sulfamic acid, 4500ppm ethylene glycol and 10ppm 1-phenyl-4-methylimidazole.

Example 3

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 8g/L sulfamic acid, 4500ppm ethylene glycol and 10ppm 1-phenyl-4-methylimidazole.

Example 4

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 8g/L sulfamic acid, 6000ppm ethylene glycol and 10ppm 1-phenyl-4-methylimidazole.

Example 5

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 8g/L sulfamic acid, 4500ppm ethylene glycol and 5ppm 1-phenyl-4-methylimidazole.

Example 6

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 12g/L sulfamic acid, 4000ppm isopropanol and 10ppm 1-phenyl-4-methylimidazole.

Example 7

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.1g/L AEC-3Na, 60g/L sulfuric acid, 12g/L sulfamic acid, 4000ppm isopropanol and 10ppm 1-phenyl-4-methylimidazole.

Example 8

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 8g/L sulfamic acid, 4000ppm isopropanol and 10ppm 1-phenyl-4-methylimidazole.

Example 9

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 8g/L sulfamic acid, 6000ppm isopropanol and 10ppm 1-phenyl-4-methylimidazole.

Example 10

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 8g/L sulfamic acid, 4000ppm isopropanol and 5ppm 1-phenyl-4-methylimidazole.

Example 11

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 12g/L sulfamic acid, 4000ppm isopropanol and 15ppm 2-amino-5-mercapto-1, 3, 4-thiadiazole.

Example 12

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.1g/L AEC-3Na, 60g/L sulfuric acid, 12g/L sulfamic acid, 4000ppm isopropanol and 15ppm 2-amino-5-mercapto-1, 3, 4-thiadiazole.

Example 13

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 8g/L sulfamic acid, 4000ppm isopropanol and 15ppm 2-amino-5-mercapto-1, 3, 4-thiadiazole.

Example 14

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 8g/L sulfamic acid, 6000ppm isopropanol and 15ppm 2-amino-5-mercapto-1, 3, 4-thiadiazole.

Example 15

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 8g/L sulfamic acid, 4000ppm isopropanol and 8ppm 2-amino-5-mercapto-1, 3, 4-thiadiazole.

Example 16

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 12g/L sulfamic acid, 4500ppm ethylene glycol and 15ppm 2-amino-5-mercapto-1, 3, 4-thiadiazole.

Example 17

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.1g/L AEC-3Na, 60g/L sulfuric acid, 12g/L sulfamic acid, 4500ppm ethylene glycol and 15ppm 2-amino-5-mercapto-1, 3, 4-thiadiazole.

Example 18

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 8g/L sulfamic acid, 4500ppm ethylene glycol and 15ppm 2-amino-5-mercapto-1, 3, 4-thiadiazole.

Example 19

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 8g/L sulfamic acid, 6000ppm ethylene glycol and 15ppm 2-amino-5-mercapto-1, 3, 4-thiadiazole.

Example 20

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 8g/L sulfamic acid, 4500ppm ethylene glycol and 8ppm 2-amino-5-mercapto-1, 3, 4-thiadiazole.

Example 21

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 15g/L citric acid, 4500ppm ethylene glycol and 10ppm 1-phenyl-4-methylimidazole.

Example 22

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.1g/L AEC-3Na, 60g/L sulfuric acid, 15g/L citric acid, 4500ppm ethylene glycol and 10ppm 1-phenyl-4-methylimidazole.

Example 23

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 8g/L citric acid, 4500ppm ethylene glycol and 10ppm 1-phenyl-4-methylimidazole.

Example 24

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 8g/L citric acid, 6000ppm ethylene glycol and 10ppm 1-phenyl-4-methylimidazole.

Example 25

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 8g/L citric acid, 4500ppm ethylene glycol and 5ppm 1-phenyl-4-methylimidazole.

Example 26

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 15g/L citric acid, 4000ppm isopropanol and 10ppm 1-phenyl-4-methylimidazole.

Example 27

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.1g/L AEC-3Na, 60g/L sulfuric acid, 15g/L citric acid, 4000ppm isopropanol and 10ppm 1-phenyl-4-methylimidazole.

Example 28

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 8g/L citric acid, 4000ppm isopropanol and 10ppm 1-phenyl-4-methylimidazole.

Example 29

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 8g/L citric acid, 6000ppm isopropanol and 10ppm 1-phenyl-4-methylimidazole.

Example 30

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 8g/L citric acid, 4000ppm isopropanol and 5ppm 1-phenyl-4-methylimidazole.

Example 31

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 15g/L citric acid, 4000ppm isopropanol and 15ppm 2-amino-5-mercapto-1, 3, 4-thiadiazole.

Example 32

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.1g/L AEC-3Na, 60g/L sulfuric acid, 15g/L citric acid, 4000ppm isopropanol and 15ppm 2-amino-5-mercapto-1, 3, 4-thiadiazole.

Example 33

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 8g/L citric acid, 4000ppm isopropanol and 15ppm 2-amino-5-mercapto-1, 3, 4-thiadiazole.

Example 34

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 8g/L citric acid, 6000ppm isopropanol and 15ppm 2-amino-5-mercapto-1, 3, 4-thiadiazole.

Example 35

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-3Na, 60g/L sulfuric acid, 8g/L citric acid, 4000ppm isopropanol and 8ppm 2-amino-5-mercapto-1, 3, 4-thiadiazole.

Example 36

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-5Na (i.e. alcohol ether carboxylate, n ═ 5), 60g/L sulfuric acid, 15g/L glycolic acid, 4500ppm ethylene glycol and 15ppm 1-p-toluene-4-methylimidazole.

Example 37

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.1g/L AEC-5Na, 60g/L sulfuric acid, 15g/L glycolic acid, 4500ppm ethylene glycol and 15ppm 1-p-toluene-4-methyl imidazole.

Example 38

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-5Na, 60g/L sulfuric acid, 8g/L glycolic acid, 4500ppm ethylene glycol and 15ppm 1-p-toluene-4-methyl imidazole.

Example 39

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-5Na, 60g/L sulfuric acid, 8g/L glycolic acid, 6000ppm ethylene glycol and 15ppm 1-p-toluene-4-methyl imidazole.

Example 40

A deep cleaning agent suitable for a circuit board comprises the following components in concentration: 0.5g/L AEC-5Na, 60g/L sulfuric acid, 8g/L glycolic acid, 4500ppm ethylene glycol and 8ppm 1-p-toluene-4-methyl imidazole.

Comparative example 1

A cleaning agent comprises AEC-3Na 0.5 g/L.

Comparative example 2

A cleaning agent comprises AEC-3Na 0.5g/L, sulfuric acid 60g/L and citric acid 10 g/L.

Comparative example 3

A cleaning agent comprises AEC-3Na 0.5g/L, sulfuric acid 60g/L, citric acid 10g/L and ethylene glycol 4000 ppm.

Comparative example 4

A cleaning agent comprises 60g/L sulfuric acid, 12g/L sulfamic acid, 4000ppm ethylene glycol and 10ppm 1-phenyl-4-methylimidazole.

Comparative example 5

A cleaning agent comprises AEC-3Na 0.5g/L, ethylene glycol 4000ppm, and 1-phenyl-4-methylimidazole 10 ppm.

Comparative example 6

A cleaning agent comprises AEC-3Na 0.5g/L, sulfuric acid 60g/L, sulfamic acid 12g/L and 1-phenyl-4-methylimidazole 10 ppm.

Comparative example 7

A commercially available cleaning agent A is sold under the trade name QL-7003.

The cleaning agents of the above examples 1-40 and comparative examples 1-7 are adopted, 47 groups are adopted, and horizontal spraying is respectively carried out on the copper surfaces of the PCB boards of the same batch at 35 ℃, wherein 10 boards in each group have the linear velocity of 4m/s and the time of 30 s. Before spraying, obvious fingerprints are pressed on the copper surface of each PCB. After the spraying is finished, the PCB is washed by overflow water, then the PCB is dried under the condition of 80 ℃, and finally the cleanness degree of the surface, the protection degree of the copper surface (SEM picture) and the existence of residues on the surface of the PCB (EDS elemental analysis) are compared, and the results are detailed in table 1, table 2, table 3, table 4 and figures 1 to 47.

TABLE 1 results of the degree of cleaning of copper surfaces after cleaning with the inventive cleaning agent

TABLE 2 results of degree of cleaning of copper surfaces after cleaning with comparative example cleaner

Table 3 EDS elemental analysis results of copper surfaces cleaned with the inventive cleaner

TABLE 4 EDS elemental analysis results of copper surfaces after cleaning with comparative example cleaning agent

As can be seen from the results in tables 1 and 3, after the cleaning agent of the present application is used for cleaning copper surfaces, oil stains and printed fingerprints can be well removed; the residual O on the copper surface is less than 0.3 percent, and the residual C is less than 0.9 percent, which indicates that the deep cleaning agent is suitable for the circuit board. After the cleaning, the copper surface can not be oxidized immediately, and the continuous oxidation resistance time is 1 to 3 hours, even can reach 4 to 8 hours. As can be seen from the results in tables 3 and 4, in examples 1 to 40, N in the copper surface is mainly derived from the nitrogen-containing copper surface protective agent. Comparative example 1 has a high N content and is derived from oil stains and the like that are not removed from the copper surface. In comparative examples 4 to 6, N in the copper surface was derived from the nitrogen-containing copper surface protective agent. On the other hand, since it is derived from the oil stain and the like which are not removed on the copper surface, the N content is higher than that in examples 1 to 40, i.e., comparative examples 4 to 6 are inferior in cleaning ability.

In conclusion, the deep cleaning agent suitable for the circuit board and the use method thereof provided by the invention are suitable for the production process of the circuit board, can thoroughly clear dirt such as surface grease on the copper surface, can solve the problem of deep oxidation of the copper layer of the circuit board, have continuous oxidation resistance and are low in sewage treatment difficulty after application.

The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes performed by the present specification and drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.