WO2021103361A1

WO2021103361A1 - Blackening liquid containing no bactericide

Info

Publication number: WO2021103361A1
Application number: PCT/CN2020/081267
Authority: WO
Inventors: 丁林; 徐旭; 付海罗; 聂晓霖
Original assignee: 南京科润工业介质股份有限公司; 南京科润工业技术有限公司
Priority date: 2019-11-27
Filing date: 2020-03-26
Publication date: 2021-06-03
Also published as: CN111073430B; CN111073430A

Abstract

Disclosed in the present invention is a blackening liquid containing no bactericide, consisting of the following components in parts by mass: 45-80 parts of a cationic polymer emulsion, 1-3 parts of a nonionic emulsifier, 0-3 parts of organic alcohol amine, 1-3 parts of a film forming auxiliary agent, 1-5 parts of water-based color paste, and 15-50 parts of water. Use of the blackening liquid in the present invention in treating a workpiece can enable the appearance of a product to be blackened to meet requirements of glossy black and corrosion resistance, and can also eliminate excessive abuse of bactericides in the blackening liquid, thereby reducing the risk of harm to a human body, prolonging the service time of the working liquid, and finally reducing manpower and material costs of frequently replacing the liquid in a tank.

Description

A blackening liquid without bactericide

Technical field

The invention relates to a blackening liquid containing no bactericide and belongs to the technical field of blackening of workpieces.

Background technique

The blackening process refers to the formation of a dense black protective film on the surface of the metal workpiece by physical or chemical methods, thereby enhancing the anti-rust ability of the workpiece and beautifying the appearance of the workpiece. According to different film forming principles, the blackening process can be divided into oxidation blackening, normal temperature blackening, phosphating blackening and residual heat blackening. Residual heat blackening is to use the residual heat of the workpiece during heat treatment or other processing to make the steel workpiece form a layer of black polymer resin film that is firmly bonded and not easy to fall off at the moment of contact with the blackening liquid on the surface of the workpiece.

In the waste heat blackening technology, in order to ensure the stability of the resin emulsion, the working fluid needs to be maintained at about 30°C to 50°C. During long-term use, due to the harsh working conditions of the production process, the working fluid is very prone to bacterial corruption. When the smell is serious, the whole tank of the working fluid will be scrapped. By analyzing the reasons for the corruption and smell of the tank liquid, it was found that due to the proliferation of bacteria in the working liquid, the key resin active ingredient of the blackening working liquid is the nutrient substance of the bacteria. At the same time as the large number of bacteria multiplying, the effective ingredient of the working liquid is blackened and filmed. It is consumed in a large amount, resulting in the deterioration of the appearance quality of the blackened workpiece, and even the phenomenon of scrap or rework. When the working fluid is corrupted, the work fluid is changed and the working fluid tank is cleaned, which causes huge losses due to shutdown and production. In order to avoid losses, a common method in the industry is to introduce fungicides, such as BK, MBM, etc., into the waste heat blackening agent stock solution. In recent years, due to the excessive use of fungicides, some microorganisms have developed drug resistance, leading to a sharp increase in the amount of fungicides, which not only led to a substantial increase in the cost of on-site use, but also was not friendly to the human body and the environment, such as the emergence of operators under certain working conditions Allergies.

technical problem

In order to solve the problems in the prior art, the present invention provides a bactericide-free blackening liquid. The blackening liquid contains a cationic polymer emulsion. The surface of the cationic polymer emulsion has a positive charge (with concentrated charge density). , The positive charge can be effectively adsorbed with the negative charge on the surface of the bacterial cell membrane, which damages the normal metabolism of the bacteria, and then kills the bacteria, thereby realizing the antibacterial and antiseptic of the blackening liquid.

Technical solutions

A blackening liquid without bactericide, consisting of the following parts by mass: 45~80 parts of cationic polymer emulsion, 1~3 parts of non-ionic emulsifier, 0~3 parts of organic alcohol amine, 1~3 parts Parts of film-forming aids, 1~5 parts of water-based color paste and 15~50 parts of water.

Among them, the cationic polymer emulsion is a quaternary ammonium salt type cationic acrylic resin emulsion or a quaternary phosphonium salt cationic acrylic resin emulsion.

Wherein, the cationic polymer emulsion includes the following components in mass fraction: 4.5% cationic emulsifier, 0.5% initiator, 8% styrene, 15% methyl methacrylate, 13% butyl acrylate , 1% acrylic acid, 1% acrylonitrile, 0.5% methacrylic acid, 0.5% phosphate functional monomer and the balance is water.

Wherein, the cationic polymer emulsion is prepared by the following method, which specifically includes the following steps:

(1) Add the cationic emulsifier of the formula into water, heat it in an oil bath after ultrasonic stirring, until the cationic emulsifier is completely dissolved, and a cationic emulsion is obtained;

(2) Mix the formulated functional monomers of styrene, methyl methacrylate, butyl acrylate, acrylic acid, acrylonitrile, methacrylic acid and phosphate to obtain mixed monomer materials; mix the monomer materials while stirring Add dropwise to the cationic emulsion, and gradually increase the stirring speed after the addition is complete;

(3) After the monomer emulsification is completed, the obtained emulsion is divided into two parts, one of which has the quality of 2/3 of the entire emulsion, which is emulsion I; the other has the quality of the entire emulsion. 1/3 of the liquid mass is emulsion II;

(4) Heat the emulsion II in an oil bath while stirring. When the temperature of the emulsion II rises to 80°C, add an initiator to the emulsion II, and the emulsion will produce a blue light effect after dripping for 15 to 30 minutes; The dropping amount of the agent is 1/3 of the total amount of the initiator;

(5) After the blue light effect of the emulsion, continue to react for 10-20 minutes, and then start to add emulsion I. The dripping rate of emulsion I is to be completed within 2 to 3 hours; at the same time, the remaining amount accounts for 2% of the total initiator. /3 of the initiator has also been added simultaneously;

(6) After the dripping of emulsion I and the remaining initiator is finished, keep 80 ℃ to continue the reaction for 30 min, after the reaction, adjust the pH of the emulsion to neutral;

(7) Filter the obtained emulsion with a 100-mesh sieve.

The cationic polymer emulsion of the present invention can only obtain a blackening liquid that can blacken into a dense corrosion-resistant film and has antibacterial properties only under such monomer ratio and process conditions. The preparation process of the cationic polymer emulsion of the present invention can obtain a qualified resin emulsion by controlling the dropping rate and the reaction temperature. Since the entire reaction is an exothermic reaction, the temperature will continuously change. If the reaction temperature cannot be controlled, it will cause explosion. , Resulting in failure of the polymerization reaction, and no emulsion can be obtained.

Among them, the nonionic emulsifier is one or two or more of Tween-80, Span-80, fatty acid alkoxylate, fatty alcohol alkoxylate, fatty acid amide, fatty alcohol polyoxyethylene ether. Proportional mixing.

Among them, the organic alcohol amine is one or a mixture of any two or more of monoethanolamine, triethanolamine, isopropanolamine or diglycolamine in any ratio.

Among them, the film-forming aids include wetting agents, thickeners, defoamers, leveling agents, pH regulators and corrosion inhibitors.

Among them, the pigment used in the water-based color paste is one or two or more of carbon black, iron oxide black, chrome black, aniline black, phthalocyanine blue, phthalocyanine green, titanium dioxide, zinc oxide, or aluminum oxide in any ratio mixing.

Dilute the above-mentioned blackening liquid with water into a solution with a mass fraction of 10-30%, immerse the steel workpiece with a temperature of 300-500 degrees in the blackening liquid solution with a mass fraction of 10-30%, and take it out after soaking for 10-30 seconds The workpiece is dried with hot air to form a blackening film layer with good corrosion resistance and strong coverage on the surface of the workpiece. The blackening working fluid of the present invention can not grow bacteria during the normal use cycle (six months to one year) , No smell, and stable quality of blackened appearance.

Beneficial effect

When the blackening liquid of the present invention is used to treat the workpiece, it can not only make the appearance of the blackened product meet the requirements of black, bright and corrosion resistance, but also can prevent the excessive abuse of the fungicide in the blackening liquid, thereby reducing the risk of harm to the human body, and The use time of the working fluid is prolonged, and finally the manpower and material costs of frequently replacing the tank fluid are reduced; the blackening fluid of the present invention can be widely used in various specifications of fasteners, chains, springs, prestressed anchors and various types of The blackening treatment of machinery and auto parts is especially suitable for the working conditions that are sensitive to the use of fungicides in the continuous production process, and the working fluid is frequently corrupted and smelly.

Embodiments of the present invention

The technical solution of the present invention will be further described below in conjunction with specific embodiments.

Example 1

Mix 45 parts of quaternary ammonium salt type cationic acrylic resin emulsion, 1 part of non-ionic emulsifier, 1 part of organic alcohol amine, 1.5 parts of film forming aids, 2 parts of water-based carbon black paste and 49.5 parts of water, and stir evenly to prepare antibacterial type Blackening liquid.

Heat the M8 outer hexagonal bolts in the mesh belt type tempering furnace to 450 degrees. After heat preservation for 1 hour, immerse the mesh belt in the blackening liquid solution with a mass fraction of 15%, soak in the blackening liquid for 30 seconds and then follow the mesh belt. Lift the liquid, and dry the workpiece with 110 degrees hot air to obtain a blackened film with uniform appearance and complete coverage.

The workpiece is blackened by waste heat treated with a blackening liquid with a mass fraction of 15%. The workpiece has a black and bright appearance. The 5% neutral salt spray test is carried out in accordance with GB/T 10125, and the salt spray resistance test time is not less than 72 hours.

The blackening liquid of Example 1 was used continuously for ten months without decay or smell, and the blackening effect was stable.

The quaternary ammonium salt type cationic acrylic resin emulsion used in Example 1 includes the following components in mass fraction: 4.5% quaternary ammonium salt type cationic emulsifier, 0.5% initiator, 8% styrene, 15% methacrylic acid Methyl ester, 13% butyl acrylate, 1% acrylic acid, 1% acrylonitrile, 0.5% methacrylic acid, 0.5% phosphate functional monomer and the balance is water.

The quaternary ammonium salt type cationic acrylic resin emulsion is prepared by the following method, which specifically includes the following steps:

(1) Accurately weigh the cationic emulsifier and monomer (mixed) according to the formula quantity;

(2) Add the amount of deionized water distributed by the emulsifier to the cationic emulsifier and dissolve it ultrasonically; set up a four-necked flask stirring device, separate the stirring device from the oil bath heating device, and heat the oil bath to 90°C while stirring; use During the emulsification time, heat up the oil bath and keep the temperature stable;

(3) After the emulsifier is dissolved, transfer the obtained emulsion to a four-necked flask, slowly turn on the electric stirring device (low speed, to avoid foaming caused by stirring); transfer the weighed monomer mixture to a constant pressure drop In the funnel, slowly open the cock of the constant pressure dropping funnel, and control the monomer dropping speed to be 2~2.5h after the addition is completed. Gradually increase the speed of the stirring device. The speed can be increased to medium to high speed in about 15 minutes. (Determined according to the foam condition of the emulsion), high-speed emulsification;

(4) During the monomer emulsification process, do not leave the operation for a long time (①The constant-pressure dropping funnel has an unconstant dripping speed and the dripping speed will change; ②The stability of the device needs to be ensured during the high-speed stirring process); During the emulsification time, accurately weigh the initiator into a beaker and dissolve it with deionized water;

(5) After the monomer is added, continue to stir at high speed for 30 minutes, stop stirring, test the pH value of the emulsion, and record the pH value;

(6) After the monomer emulsification stage is completed, remove the stirring device, weigh 2/3 of the emulsion quality into the reagent bottle with lid, transfer the remaining 1/3 of the emulsion together with the four-necked flask to the oil bath, and rebuild Electric stirring device, plug in thermometer, cooling reflux device, constant pressure dropping funnel;

(7) Turn on the electric stirring, control the speed to 300 rpm, observe the thermometer in the four-neck flask, wait until the temperature of the thermometer in the four-neck flask rises to 80°C, adjust the temperature of the oil bath to 85°C; Add buffer, test the pH value of the emulsion, and record the pH value;

(8) When the temperature of the emulsion in the four-neck flask rises to about 80°C, start to slowly add the initiator. At this stage, the total amount of the initiator is controlled to not exceed 1/3 of the total amount of all initiators; during the dropping process, Continue to pay attention to changes in emulsion temperature and emulsion appearance. The blue light effect of the emulsion can be observed in about 15 to 30 minutes;

(9) After the emulsion produces the blue light effect, continue to react for 10-20 minutes, and then start to drip the emulsion; control the dripping rate of the emulsion which accounts for 2/3 of the total emulsion to complete the dripping within 2 to 3 hours; at the same time, ensure the remaining initiator Synchronous dripping finished;

(10) After the emulsion and initiator have been added dropwise, keep about 80 ℃ and continue to react for 30 min; measure the pH value of the emulsion and record the pH value;

(11) After the reaction, add a small amount of ammonia water to adjust the pH of the emulsion to neutral (the pH value is 7~8 at this time);

(12) Filter the resin emulsion with a 100-mesh sieve, and reserve the filtered emulsion for later use.

Example 2

Mix 80 parts of quaternary phosphonium salt type cationic acrylic resin emulsion, 1 part of non-ionic emulsifier, 3 parts of film-forming aids, 3 parts of water-based carbon black paste, 1 part of phthalocyanine blue paste and 18 parts of water. Antibacterial blackening liquid.

The blackening liquid of Example 2 was used continuously for twelve months without decay and no smell, and the blackening effect was stable. The waste heat blackened workpiece processed by the blackening liquid of Example 2 with a mass fraction of 15% was subjected to a 5% neutral salt spray test according to GB/T 10125, and the salt spray resistance test time was not less than 72 hours.

The quaternary phosphonium cationic acrylic resin emulsion used in Example 2 includes the following components in mass fraction: 4.5% quaternary phosphonium cationic emulsifier, 0.5% initiator, 8% styrene, 15% methacrylic acid Methyl ester, 13% butyl acrylate, 1% acrylic acid, 1% acrylonitrile, 0.5% methacrylic acid, 0.5% phosphate functional monomer and the balance is water.

The above-mentioned quaternary phosphonium cationic acrylic resin emulsion is prepared by the following method, which specifically includes the following steps:

The antibacterial cationic polymer emulsion obtained in the present invention bears the responsibility of sterilization and antibacterial at the same time.

The function of blackening and film formation can be said to be a combination of blackening, film formation and sterilization.

Claims

A blackening liquid without bactericide, which is characterized in that it is composed of the following parts by mass: 45 to 80 parts of cationic polymer emulsion, 1 to 3 parts of nonionic emulsifier, and 0 to 3 parts of organic alcohol amine , 1~3 parts of film-forming aids, 1~5 parts of water-based color paste and 15~50 parts of water.
The bactericide-free blackening liquid according to claim 1, wherein the cationic polymer emulsion is a quaternary ammonium salt cationic acrylic resin emulsion or a quaternary phosphonium salt cationic acrylic resin emulsion.
The bactericide-free blackening liquid according to claim 2, wherein the cationic polymer emulsion comprises the following components in mass fraction: 4.5% cationic emulsifier, 0.5% initiator, 8% Styrene, 15% methyl methacrylate, 13% butyl acrylate, 1% acrylic acid, 1% acrylonitrile, 0.5% methacrylic acid, 0.5% phosphate functional monomer and the balance is water .
The bactericide-free blackening liquid according to claim 3, wherein the cationic polymer emulsion is prepared by the following method, which specifically includes the following steps:

(1) Add the cationic emulsifier of the formula into water, heat it in an oil bath after ultrasonic stirring, until the cationic emulsifier is completely dissolved, and a cationic emulsion is obtained;

(2) Mix the formulated functional monomers of styrene, methyl methacrylate, butyl acrylate, acrylic acid, acrylonitrile, methacrylic acid and phosphate to obtain mixed monomer materials; mix the monomer materials while stirring Add dropwise to the cationic emulsion, and gradually increase the stirring speed after the addition is complete;

(3) After the monomer emulsification is completed, the obtained emulsion is divided into two parts, one of which has the quality of 2/3 of the entire emulsion, which is emulsion I; the other has the quality of the entire emulsion. 1/3 of the liquid mass is emulsion II;

(4) Heat the emulsion II in an oil bath while stirring. When the temperature of the emulsion II rises to 80°C, add an initiator to the emulsion II, and the emulsion will produce a blue light effect after dripping for 15 to 30 minutes; The dropping amount of the agent is 1/3 of the total amount of the initiator;

(5) After the emulsion produces blue light effect, continue to react for 10-20 min, start to drip emulsion I, the dripping rate of emulsion I is to finish dripping in 2~3h; at the same time, the remaining initiator, which accounts for 2/3 of the total amount of initiator, is also dripped simultaneously;

(6) After the dripping of emulsion I and the remaining initiator is finished, keep 80 ℃ to continue the reaction for 30 min, after the reaction, adjust the pH of the emulsion to neutral;

(7) Filter the obtained emulsion with a 100-mesh sieve.
The bactericide-free blackening liquid according to claim 1, wherein the non-ionic emulsifier is Tween-80, Span-80, fatty acid alkoxylate, fatty alcohol alkoxylate, fatty acid amide , One or two or more of the fatty alcohol polyoxyethylene ethers are mixed in any ratio.
The bactericide-free blackening liquid according to claim 1, wherein the organic alcohol amine is one or two or more of monoethanolamine, triethanolamine, isopropanolamine, or diglycolamine. Proportional mixing.
The bactericide-free blackening liquid according to claim 1, wherein the film-forming auxiliary agent includes a wetting agent, a thickening agent, a defoaming agent, a leveling agent, a pH adjusting agent and a corrosion inhibitor.
The blackening liquid without fungicide according to claim 1, wherein the pigment used in the aqueous color paste is carbon black, iron oxide black, chrome black, aniline black, phthalocyanine blue, phthalocyanine green, titanium dioxide, One or two or more of zinc oxide or aluminum oxide are mixed in any ratio.