A combined solvent and its application

Abstract

The present invention belongs to the technical field of cleaning agents, and in particular, relates to a combined solvent and its application. The Kb value of the combined solvent of perfluorohexene, γ-valerolactone and trans-1,2-dichloroethylene provided by the present invention is between 50-100, which indicates that the solvent not only has good solubility and removal capabilities for organic pollutants such as mineral oil, synthetic oil, rosin flux and silicone oil, but also has good compatibility with rubber and plastic materials, and will not produce swelling effect on the material matrix, affecting the normal use of electronic devices. When the combined solvent is a certain amount of perfluorohexene, γ-valerolactone and trans-1,2-dichloroethylene, its core parameters are flash point>45°C, acid value<0.1ppm, kinematic viscosity<0.5mm 2 / s (40℃), the kauri resin butanol value (KB value) is between 50‑100.

Description

Technical Field

[0001] The invention relates to the technical field of cleaning agents, and in particular to a combined solvent and application thereof. Background Art

[0002] Modern microelectronics industry and medical devices are gradually developing towards micro-precision processing. The deep cleaning of these electronic devices and medical devices has become a key process in their processing. Usually, such devices are cleaned by immersion in organic solvents to dissolve and remove welding residues, grease and surface residues during processing. Traditional cleaning solvents include halogenated hydrocarbon reagents such as 1,1,2-trichloro-1,2,2-trifluoroethane and 1,1,2-trichloroethylene. Although these reagents have excellent cleaning performance, they have strong biological toxicity and environmental hazards, as well as strong ozone depletion. In recent years, they have been gradually banned. Trans-1,2-dichloroethylene has similar cleaning capabilities to 1,1,2-trichloro-1,2,2-trifluoroethane and 1,1,2-trichloroethylene, extremely low biological toxicity and excellent environmental performance, and can be used to replace traditional cleaning solvents that are harmful to organisms and the environment.

[0003] However, trans-1,2-dichloroethylene has many disadvantages when used alone as a cleaning agent. For example, the flash point of trans-1,2-dichloroethylene is only -11°C, and it has certain combustion and explosion hazards during use; the Cl in its molecular structure is unstable and is easily acidified during cleaning, storage and transportation, forming trace amounts of H + , which can easily damage electronic devices and medical devices; there is a C=C double bond in its molecular structure, which is easy to undergo polymerization under conditions such as light and heating to generate macromolecular compounds, affecting product purity and cleaning effects. These shortcomings have greatly restricted the application of trans-1,2-dichloroethylene in the field of electronic and medical device cleaning. How to solve the shortcomings of trans-1,2-dichloroethylene at the application end is the key factor in promoting its application.

[0004] The existing technologies mainly focus on solving the flammability problem of trans-1,2-dichloroethylene, that is, by adding new components to increase the flash point of the compound, but pay less attention to its shortcomings of easy acidification and easy polymerization. The added components mainly include hydrofluoroalkanes (pentafluoroethane, pentafluorobutane, decafluoropentane, etc.), hydrofluoroethers (methyl nonafluorobutyl ether, octafluoropentyl ether, etc.), hydrofluoroolefins (nonafluorohexene, hexafluorobutene, etc.), hydrofluorochloroolefins (monochlorotrifluoropropylene, etc.) and hydrofluoroolefin ethers (methyl perfluoroheptene ether, etc.). Although these technologies can solve the flammability problem of dichloroethylene, they do not solve the problems of poor stability and easy acidification. On the other hand, when introducing new components, the existing technologies are also prone to new problems such as increased viscosity and changes in cleaning ability. For example, the increase in the viscosity of the mixed solvent will affect the flow and infiltration of trans-1,2-dichloroethylene in some complex structure components (such as micro grooves on circuit boards, etc.), thereby affecting the cleaning effect. If the solvent cleaning ability is too high, it will cause the solvent to swell some organic components on electronic devices and medical equipment, affecting the normal function of these devices; if the cleaning ability is too low, the solvent will have insufficient ability to dissolve impurities such as grease, affecting the cleaning effect.

[0005] In short, the prior art lacks a solution that can simultaneously solve the problems of flammability, acidification, and polymerization. Summary of the invention

[0006] The purpose of the present invention is to provide a combined solvent and application thereof, which can solve the problems of being flammable, easy to acidify and easy to polymerize.

[0007] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0008] The present invention provides a combined solvent, which comprises the following components in parts by mass:

[0009] 5-50 parts of perfluorohexene;

[0010] γ-valerolactone 0.5-5 parts;

[0011] 50-95 parts of trans-1,2-dichloroethylene.

[0012] Preferably, the perfluorohexene comprises one or more of (E)-perfluoro-3-methyl-2-pentene, perfluoro-2-methyl-2-pentene and (Z)-perfluoro-3-methyl-2-pentene.

[0013] Preferably, when the perfluorohexene comprises perfluoro-2-methyl-2-pentene and (E)-perfluoro-3-methyl-2-pentene, the mass ratio of perfluoro-2-methyl-2-pentene to (E)-perfluoro-3-methyl-2-pentene is 20-40:60-80.

[0014] Preferably, when the perfluorohexene comprises (Z)-perfluoro-3-methyl-2-pentene and (E)-perfluoro-3-methyl-2-pentene, the mass ratio of (Z)-perfluoro-3-methyl-2-pentene to (E)-perfluoro-3-methyl-2-pentene is 40-60:40-60.

[0015] Preferably, when the perfluorohexene comprises perfluoro-2-methyl-2-pentene and (Z)-perfluoro-3-methyl-2-pentene, the mass ratio of perfluoro-2-methyl-2-pentene to (Z)-perfluoro-3-methyl-2-pentene is 50-70:30-50.

[0016] Preferably, when the perfluorohexene comprises perfluoro-2-methyl-2-pentene, (Z)-perfluoro-3-methyl-2-pentene and (E)-perfluoro-3-methyl-2-pentene, the mass ratio of perfluoro-2-methyl-2-pentene, (Z)-perfluoro-3-methyl-2-pentene and (E)-perfluoro-3-methyl-2-pentene is 20~40:20~40:30~50.

[0017] Preferably, the following components are included in parts by mass:

[0018] 10-40 parts of perfluorohexene;

[0019] γ-valerolactone 2-4 parts;

[0020] 60-80 parts of trans-1,2-dichloroethylene.

[0021] The invention also provides the use of the combined solvent in removing organic grease or as a cooling medium for an electronic equipment cooling system.

[0022] Preferably, the organic grease comprises mineral oil, synthetic oil, rosin flux and silicone oil.

[0023] The present invention uses a combined solvent containing perfluorohexene, γ-valerolactone and trans-1,2-dichloroethylene as an azeotrope or a near-azeotrope, which has the advantages of high flash point, high stability, easy flow and suitable cleaning ability. The combined solvent has a flash point of >45°C, an acid value of <0.1 ppm, and a kinematic viscosity of <0.5 mm 2 / s (40℃), the shell rosin butanol value (KB value) is between 50 and 100. It is a non-toxic, harmless and non-corrosive cleaning agent that can meet the cleaning and dissolving power requirements of electronic devices and medical devices. It is an efficient cleaning agent with high economic value and application prospects. DETAILED DESCRIPTION

[0024] The present invention provides a combined solvent, which comprises the following components in parts by mass:

[0025] 5-50 parts of perfluorohexene;

[0026] γ-valerolactone 0.5-5 parts;

[0027] 50-95 parts of trans-1,2-dichloroethylene.

[0028] In the present invention, the perfluorohexene is 5 to 50 parts, preferably 10 to 40 parts, and more preferably 20 to 30 parts.

[0029] In the present invention, the γ-valerolactone is 0.5 to 5 parts, preferably 2 to 4 parts, and more preferably 2 to 3 parts.

[0030] In the present invention, the trans-1,2-dichloroethylene is 50 to 95 parts, preferably 60 to 80 parts, and more preferably 65 to 75 parts.

[0031] In the present invention, the perfluorohexene comprises one or more of (E)-perfluoro-3-methyl-2-pentene, perfluoro-2-methyl-2-pentene and (Z)-perfluoro-3-methyl-2-pentene; when the perfluorohexene comprises two or three of them, the proportions of the substances can be arbitrary.

[0032] In the present invention, perfluorohexene can be specifically the following preferred embodiments:

[0033] The mass ratio of perfluoro-2-methyl-2-pentene to (E)-perfluoro-3-methyl-2-pentene is 20-40:60-80, more preferably 25-35:65-75, and even more preferably 30:70;

[0034] The mass ratio of (Z)-perfluoro-3-methyl-2-pentene to (E)-perfluoro-3-methyl-2-pentene is 40-60:40-60, more preferably 45-55:45-55, and even more preferably 50:50;

[0035] The mass ratio of perfluoro-2-methyl-2-pentene to (Z)-perfluoro-3-methyl-2-pentene is 50-70:30-50, more preferably 55-65:35-45, and even more preferably 60:40;

[0036] The mass ratio of perfluoro-2-methyl-2-pentene, (Z)-perfluoro-3-methyl-2-pentene and (E)-perfluoro-3-methyl-2-pentene is 20-40:20-40:30-50, more preferably 25-35:25-35:35-45, and even more preferably 30:30:40.

[0037] Specifically, (E)-perfluoro-3-methyl-2-pentene is , perfluoro-2-methyl-2-pentene is , (Z)-perfluoro-3-methyl-2-pentene is .

[0038] The present invention has no special requirements on the preparation method of the mixed solvent, and it only needs to be mixed evenly.

[0039] The present invention also provides the use of the combined solvent in removing organic grease or as a cooling medium for an electronic equipment cooling system, especially organic grease in electronic devices and medical equipment; the organic grease comprises mineral oil, synthetic oil, rosin soldering flux and silicone oil.

[0040] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0041] At room temperature, a certain amount of perfluorohexene, γ-valerolactone and trans-1,2-dichloroethylene were weighed, mixed evenly and prepared into a combined solvent. The type of perfluorohexene and the mass fraction of each component in the combined solvent are shown in Table 1 below.

[0042] Table 1. Types of perfluorohexene and mass fractions of each component in Examples 1 to 10

[0043]

[0044]

[0045] in,

[0046] In Example 7, the mass ratio of perfluoro-2-methyl-2-pentene to (E)-perfluoro-3-methyl-2-pentene is 30:70;

[0047] In Example 8, the mass ratio of (Z)-perfluoro-3-methyl-2-pentene to (E)-perfluoro-3-methyl-2-pentene is 50:50;

[0048] In Example 9, the mass ratio of perfluoro-2-methyl-2-pentene to (Z)-perfluoro-3-methyl-2-pentene is 60:40;

[0049] In Example 10, the mass ratio of perfluoro-2-methyl-2-pentene, (Z)-perfluoro-3-methyl-2-pentene and (E)-perfluoro-3-methyl-2-pentene is 30:30:40.

[0050] Experimental example

[0051] (1) The flash point of the combined solvent was tested according to the national standard GB / T21929-2008. First, 50 mL of the sample was measured in a test cup, and then its closed cup flash point was tested in the HK-21929A automatic Tiger closed cup flash point tester.T 闭 .

[0052] (2) The acid value of the combined solvent was tested according to the national standard GB / T41633.3-2022. A 0.100 mmol / L potassium hydroxide isopropanol standard solution was prepared for use. 5.00 g of the sample was weighed and dissolved in 20 mL of isopropanol solvent. The sample and the blank sample were then titrated in a Mettler-Toledo T5 automatic potentiometric titrator, and the volume of potassium hydroxide isopropanol standard solution consumed by the sample and the blank sample was recorded. V 1 (mL) and V 0 (mL), and the acid value of each sample was calculated according to the following formula A .

[0053]

[0054] (3) The kinematic viscosity of the combined solvent was tested according to standard ASTM D7042. 10 mL of sample was measured in a test cup and then tested in an Anton Paar SVM1001 fully automatic kinematic viscometer for 40 min. o Kinematic viscosity at C m .

[0055] (4) The combined solvent was tested for the kauri resin butanol value according to ASTM D1133-2002. KB For the test, 400 g of kauri resin was dissolved in 2 kg of n-butanol to obtain a kauri resin-n-butanol standard solution for standby use. 125 mL of toluene and 375 mL of n-heptane were mixed evenly to obtain an n-heptane-toluene standard solution for standby use. Weigh 3 portions of 20 g of kauri resin-n-butanol standard solution and place a standard turbidity card at the bottom. Toluene, n-heptane-toluene standard solution and sample were added to the 3 portions of standard solution respectively until the solution became turbid and the turbidity card could not be observed. The volumes of toluene, n-heptane-toluene standard solution and sample solution added were recorded as follows: V 1 , V 2 and V 3 Calculate the kauri resin butanol value of the sample according to the following formula: KB .

[0056]

[0057]

[0058]

[0059] From the experimental results in Table 1, it can be seen that when the combined solvent is a certain amount of perfluorohexene, γ-valerolactone and trans-1,2-dichloroethylene, its core parameter flash point>45 o C, acid value < 0.1 ppm, kinematic viscosity < 0.5 mm 2 / s (40 o C), the shellac resin butanol value (KB value) is between 50-100.

[0060] According to the experimental results of Comparative Example 1, when the content of perfluorohexene and γ-valerolactone is too low, the flash point of the combined solvent is less than 45 o C is a flammable solvent; the acid value is >0.1 ppm, and parts are easily damaged during use. The shellac butanol value (KB value) is only 37, indicating that the cleaning ability of this combination solvent is significantly reduced compared with the embodiment.

[0061] According to the experimental results of Examples 2-4, when the combined solvent contains only perfluorohexene and trans-1,2-dichloroethylene and no γ-valerolactone, the solvent is unstable, its acid value exceeds 1 ppm, and it is very easy to damage the parts during use; its kinematic viscosity is >0.5 mm 2 / s (40 o C), indicating that the flowability of the combined solvent is greatly reduced; the shellac resin butanol value (KB value) exceeds 100, indicating that the combined solvent will swell some organic matter and cause damage to the target object during the cleaning process.

[0062] According to the experimental results of Example 5, when the combined solvent contains only γ-valerolactone and trans-1,2-dichloroethylene and no perfluorohexene, its flash point is less than 45 o C, is a flammable solvent; its kinematic viscosity> 0.5 mm 2 / s (40 o C), indicating that the flowability of the combined solvent is greatly reduced; the shellac rosin butanol value (KB value) is only 32, indicating that the cleaning ability of the combined solvent is significantly reduced compared with the embodiment.

[0063] In the present invention, perfluorohexene is non-flammable, has no flash point, low viscosity, moderate cleaning ability, and has good wettability and material compatibility; trans-1,2-dichloroethylene has high cleaning ability; γ-valerolactone can effectively capture free radicals in the mixture system, inhibit the polymerization of trans-1,2-dichloroethylene, and reduce its acid value. These three substances work synergistically to form azeotropes or quasi-azeotropes, and the resulting combined solvent has stable properties, high flash point, low acid value, low viscosity, and moderate cleaning ability.

[0064] The results of the examples show that the Kb value of the combined solvent of perfluorohexene, γ-valerolactone and trans-1,2-dichloroethylene provided by the present invention is between 50 and 100, which indicates that the solvent not only has good solubility and removal ability for organic pollutants such as mineral oil, synthetic oil, rosin flux and silicone oil, but also has good compatibility with rubber and plastic materials, and will not produce swelling effect on the material matrix, affecting the normal use of electronic devices.

[0065] At the same time, the perfluorohexene, γ-valerolactone and trans-1,2-dichloroethylene combined solvent provided by the present invention can adjust the mass fraction according to the different parts to be cleaned, balancing the material compatibility and cleaning power requirements, and the flash point is >45°C. This flexible and changeable combination makes the combined solvent have good wettability, wide application and strong applicability.

[0066] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A combined solvent, characterized in that: According to the mass percentage, it is composed of the following components: 5-50 parts of perfluorohexene; γ-valerolactone 0.5-5 parts; 50-95 parts of trans-1,2-dichloroethylene; The perfluorohexene comprises one or more of (E)-perfluoro-3-methyl-2-pentene, perfluoro-2-methyl-2-pentene and (Z)-perfluoro-3-methyl-2-pentene.

2. The combined solvent according to claim 1, characterized in that When the perfluorohexene comprises perfluoro-2-methyl-2-pentene and (E)-perfluoro-3-methyl-2-pentene, the mass ratio of perfluoro-2-methyl-2-pentene to (E)-perfluoro-3-methyl-2-pentene is 20-40:60-80.

3. The combined solvent according to claim 1, characterized in that When the perfluorohexene comprises (Z)-perfluoro-3-methyl-2-pentene and (E)-perfluoro-3-methyl-2-pentene, the mass ratio of (Z)-perfluoro-3-methyl-2-pentene to (E)-perfluoro-3-methyl-2-pentene is 40-60:40-60.

4. The combined solvent according to claim 1, characterized in that When the perfluorohexene comprises perfluoro-2-methyl-2-pentene and (Z)-perfluoro-3-methyl-2-pentene, the mass ratio of perfluoro-2-methyl-2-pentene to (Z)-perfluoro-3-methyl-2-pentene is 50-70:30-50.

5. The combined solvent according to claim 1, characterized in that: When the perfluorohexene comprises perfluoro-2-methyl-2-pentene, (Z)-perfluoro-3-methyl-2-pentene and (E)-perfluoro-3-methyl-2-pentene, the mass ratio of perfluoro-2-methyl-2-pentene, (Z)-perfluoro-3-methyl-2-pentene and (E)-perfluoro-3-methyl-2-pentene is 20-40:20-40:30-50.

6. The combined solvent according to any one of claims 1 to 5, characterized in that: According to the mass percentage, it is composed of the following components: 10-40 parts of perfluorohexene; γ-valerolactone 2-4 parts; 60-80 parts of trans-1,2-dichloroethylene.

7. Use of the combined solvent according to any one of claims 1 to 6 in removing organic grease or as a cooling medium in a cooling system of an electronic device.

8. The use according to claim 7, characterized in that: The organic grease includes mineral oil, synthetic oil, rosin soldering flux and silicone oil.

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