CN111269612B - Water-based metal protection ink and preparation method thereof - Google Patents

Abstract

The invention provides water-based metal protection ink and a preparation method thereof. The water-based metal protection ink comprises the following components in parts by weight: 20-25 parts of water-based acrylic emulsion, 55-60 parts of water-based epoxy resin, 5-10 parts of methylated amino resin, 5-10 parts of water, 0.5-1 part of water-based defoaming agent, 0.5-1 part of water-based leveling agent and 0.5-1 part of water-based coupling agent. The water-based metal protection ink is pure water-based ink with low VOC emission, has high bonding performance and good leveling effect, is low in curing temperature, high in hardness of a dried paint film, high in adhesion fastness with a substrate, good in scratch resistance and protectiveness, and good in cutting fluid polishing solution resistance and water resistance.

Description

Water-based metal protection ink and preparation method thereof

Technical Field

The invention belongs to the technical field of printing ink, and particularly relates to water-based metal protection printing ink and a preparation method thereof.

Background

Stainless steel is used as a high-strength and scratch-resistant material and is widely applied to the fields of high-end smart phones, tablet computers, industrial and commercial electronic appliances and the like. In the field of stainless steel processing, in the process of special processing techniques such as stamping, CNC, edging and polishing, the surface of stainless steel can be scratched, so that the defective rate can even reach 99%. Meanwhile, the damaged stainless steel can increase the subsequent polishing and flat grinding process, thereby increasing the production cost. In order to solve the technical problem, a plurality of protective printing inks are developed on the market, the protective printing inks are mainly sprayed on the surface of stainless steel to form a layer of protective film, and the protective film is removed after the stainless steel is processed, so that the stainless steel is protected from being damaged in the processing process. However, with the increasing requirement for environmental protection, the current oily protective oil with high VOC (volatile organic compound) emission can not meet the requirement at all, and the quality and quantity can not be guaranteed on time due to environmental protection, which seriously affects the delivery period.

CN105482549A discloses an environment-friendly sun-proof wear-resistant water-based ink and a preparation method thereof, wherein the ink comprises the following raw materials in parts by weight: 25-30% of water-based acrylic emulsion, 18-20% of deionized water, 0.2-0.5% of dispersing agent, 0.2-0.5% of dimethylethanolamine, 0.2-0.4% of wetting agent, 1.5-2% of slow drying agent, 5-10% of antiwear agent, 10-15% of anti-ultraviolet sun-screening agent, 0.2-0.4% of flatting agent and 30-35% of organic pigment. The invention adopts single acrylate emulsion to be applied to the water-based ink, has the defects of insufficient water resistance and poor adhesive force, and is difficult to achieve ideal printing effect on the metal surface.

CN108976903A discloses a high-performance environment-friendly water-based ink and a preparation method thereof, wherein the water-based ink is prepared from the following raw materials in percentage by weight: 40-60% of connecting material, 15-20% of pigment, 5-8% of ethanol, 3-5% of polyethylene wax, 1-2.5% of pH regulator, 0.2-0.5% of bacteriostatic agent, 0.2-0.5% of defoaming agent and the balance of deionized water; the connecting material is prepared from the following raw materials in percentage by weight: 95% -99% of polyurethane emulsion and 1% -5% of epoxy resin emulsion, although VOC emission of the formula is low, the used waterborne polyurethane has the defects of poor self-thickening property and poor water resistance and glossiness.

Therefore, the development of an aqueous ink with low VOC emission and good adhesion and water resistance is the focus of current research in the field.

Disclosure of Invention

Aiming at the defects of the prior art, the invention aims to provide the water-based metal protection ink and the preparation method thereof, wherein the water-based metal protection ink is pure water ink with low VOC emission, has very high bonding performance and good leveling effect, is low in curing temperature, has high hardness of a dried paint film, high adhesion fastness with a substrate, and good scratch resistance, protection performance, cutting fluid polishing solution resistance and water resistance of the paint film.

In order to achieve the purpose, the invention adopts the following technical scheme:

in a first aspect, the present invention provides an aqueous metal protection ink, comprising, in parts by weight: 20-25 parts of water-based acrylic emulsion, 55-60 parts of water-based epoxy resin, 5-10 parts of methylated amino resin, 5-10 parts of water, 0.5-1 part of water-based defoaming agent, 0.5-1 part of water-based leveling agent and 0.5-1 part of water-based coupling agent.

In the invention, the water-based acrylic emulsion, the water-based epoxy resin and the methylated amino resin are matched with each other, so that the water dispersibility of a resin system and the stability in a water dispersion are synergistically improved, the rheological property and the adhesive force to a base material of the water-based metal protection ink are improved, the discharge of VOC and the curing temperature are reduced, and the curing time is shortened. According to the invention, through the synergistic cooperation of the water-based defoaming agent, the water-based leveling agent and the water-based coupling agent, chain segments of a resin system are mutually connected under the action of hydrogen bonds, so that a three-dimensional network structure is formed, the flowing of the ink is hindered, and the viscosity of the ink is improved. The viscosity of the ink is improved, so that the shearing stress of the ink in the dispersing process is correspondingly improved, the fineness is improved, and the improvement of the fineness of the ink can improve the dryness, water resistance, adhesion fastness, glossiness and surface smoothness of the ink. Meanwhile, the viscosity of the ink is increased, the motion resistance of the system is increased, pigment particles are difficult to precipitate, and the stability of the resin system is obviously improved.

In the present invention, the weight parts of the aqueous acrylic emulsion are 20 to 25 parts, and may be, for example, 20 parts, 20.5 parts, 21 parts, 21.5 parts, 22 parts, 22.5 parts, 23 parts, 23.5 parts, 24 parts, 24.5 parts, and 25 parts.

In the present invention, the weight part of the aqueous epoxy resin is 55 to 60 parts, and may be, for example, 50 parts, 50.5 parts, 51 parts, 51.5 parts, 52 parts, 52.5 parts, 53 parts, 53.5 parts, 54 parts, 54.5 parts, or 55 parts.

In the present invention, the methylated amino resin is 5 to 10 parts by weight, for example, 5 parts, 5.5 parts, 6 parts, 6.5 parts, 7 parts, 7.5 parts, 8 parts, 8.5 parts, 9 parts, 9.5 parts, and 10 parts.

In the present invention, the water is 5 to 10 parts by weight, for example, 5 parts, 5.5 parts, 6 parts, 6.5 parts, 7 parts, 7.5 parts, 8 parts, 8.5 parts, 9 parts, 9.5 parts, and 10 parts.

In the present invention, the aqueous defoaming agent may be used in an amount of 0.5 to 1 part by weight, for example, 0.5 part, 0.55 part, 0.6 part, 0.65 part, 0.7 part, 0.75 part, 0.8 part, 0.85 part, 0.9 part, 0.95 part, or 1 part.

In the present invention, the aqueous leveling agent may be used in an amount of 0.5 to 1 part by weight, for example, 0.5 part, 0.55 part, 0.6 part, 0.65 part, 0.7 part, 0.75 part, 0.8 part, 0.85 part, 0.9 part, 0.95 part, or 1 part.

In the present invention, the aqueous coupling agent may be used in an amount of 0.5 to 1 part by weight, for example, 0.5 part, 0.55 part, 0.6 part, 0.65 part, 0.7 part, 0.75 part, 0.8 part, 0.85 part, 0.9 part, 0.95 part, or 1 part.

Preferably, the aqueous acrylic emulsion has a pH of 7 to 9, which may be, for example, 7, 7.2, 7.4, 7.6, 7.8, 8, 8.2, 8.4, 8.6, 8.8, 9. If the pH value of the water-based acrylic emulsion is higher than 9, the film fading speed of the base material and the fragment effect after the film fading are poor after the ink is formed into the film, and if the pH value of the water-based acrylic emulsion is lower than 7, the ink is not resistant to CNC and ultrasonic cleaning processes after the ink is formed into the film.

Preferably, the dynamic viscosity of the aqueous acrylic emulsion is 100 mPas, for example 100 mPas, 150 mPas, 200 mPas, 250 mPas, 300 mPas, 350 mPas, 400 mPas, 450 mPas, 500 mPas, 550 mPas, 600 mPas, 650 mPas, 700 mPas, 750 mPas, 800 mPas, 850 mPas, 900 mPas, 950 mPas, 1000 mPas. The kinematic viscosity of the invention is a viscosity at 25 ℃. If the viscosity of the aqueous acrylic emulsion is lower than 100mPa.s, the viscosity of the aqueous metal protection ink system is too low, and a sagging phenomenon occurs during spraying, and if the viscosity of the aqueous acrylic emulsion is higher than 1000mPa.s, the viscosity of the aqueous metal protection ink system is too high, and a spray head is blocked during spraying.

Preferably, the curing temperature of the aqueous acrylic emulsion is 100 ℃ to 120 ℃, and may be, for example, 100 ℃, 102 ℃, 104 ℃, 106 ℃, 108 ℃, 110 ℃, 112 ℃, 114 ℃, 116 ℃, 118 ℃ to 120 ℃. If the curing temperature of the water-based acrylic emulsion is lower than 100 ℃, a paint film formed by the ink has short ultrasonic cleaning resistant time and can not meet the processing requirement, the curing temperature of the water-based acrylic emulsion is higher than 120 ℃, and the processed workpiece is easily damaged when the ink is sprayed.

Preferably, the aqueous acrylic emulsion has a solids content of 30 to 45% by weight, and may be, for example, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45% by weight.

Preferably, the pH value of the water-based epoxy resin is 7-9; for example, 7, 7.2, 7.4, 7.6, 7.8, 8, 8.2, 8.4, 8.6, 8.8, 9 may be used. If the pH value of the water-based epoxy resin is higher than 9, the film fading speed of the base material and the fragment effect after the film fading are poor after the ink is formed into the film, and if the pH value of the water-based epoxy resin is lower than 7, the ink is not resistant to CNC and ultrasonic cleaning processes after the ink is formed into the film.

Preferably, the dynamic viscosity of the aqueous epoxy resin is 100-1000 mPas, and may be, for example, 100 mPas, 150 mPas, 200 mPas, 250 mPas, 300 mPas, 350 mPas, 400 mPas, 450 mPas, 500 mPas, 550 mPas, 600 mPas, 650 mPas, 700 mPas, 750 mPas, 800 mPas, 850 mPas, 900 mPas, 950 mPas, 1000 mPas. The kinematic viscosity of the invention is a viscosity at 25 ℃. If the viscosity of the aqueous epoxy resin is lower than 100mPa.s, the viscosity of the aqueous metal protection ink system is too low, and a sagging phenomenon occurs during spraying, and if the viscosity of the aqueous epoxy resin is higher than 1000mPa.s, the viscosity of the aqueous metal protection ink system is too high, and a spray head is blocked during spraying.

Preferably, the curing temperature of the aqueous epoxy resin is 100 ℃ to 120 ℃, and may be, for example, 100 ℃, 102 ℃, 104 ℃, 106 ℃, 108 ℃, 110 ℃, 112 ℃, 114 ℃, 116 ℃, 118 ℃ to 120 ℃. If the curing temperature of the water-based epoxy resin is lower than 100 ℃, a paint film formed by the ink has short ultrasonic cleaning resistant time, can not meet the processing requirement, the curing temperature of the water-based epoxy resin is higher than 120 ℃, and a processed workpiece is easily damaged when the ink is sprayed.

Preferably, the weight average molecular weight of the aqueous epoxy resin is 10000-30000, and may be 10000, 12000, 14000, 16000, 18000, 20000, 22000, 24000, 26000, 28000, 30000, for example.

Preferably, the aqueous epoxy resin comprises any one of or a combination of at least two of bisphenol A type epoxy resin, bisphenol F type epoxy resin, o-cresol novolac epoxy resin, p-tert-butyl phenol novolac epoxy resin or bisphenol S type epoxy resin.

Preferably, the methylated amino resin is a high imino methylated amino resin. The highly imino methylated amino resin has an end-capping structure which retains a certain amount of unreacted active hydrogen atoms and also retains a certain amount of methylol groups. When the epoxy resin is matched with acrylic emulsion and epoxy resin, the curing property of a resin system is further improved due to higher content of imino in the resin, so that the curing time is shortened, and the emission of VOC is reduced.

The opening temperature of the highly iminomethylated amino resin is preferably 90 to 120 ℃ and may be, for example, 90 ℃, 92 ℃, 94 ℃, 96 ℃, 98 ℃, 100 ℃, 112 ℃, 114 ℃, 116 ℃, 118 ℃ or 120 ℃. If the unsealing temperature of the high imino methylated amino resin is lower than 90 ℃, the storage stability of the aqueous metal protection ink is poor, and if the unsealing temperature of the high imino methylated amino resin is higher than 120 ℃, the processed workpiece is easily damaged when the ink is sprayed.

Preferably, the high imino methylated amino resin comprises any one of LY211, R-717, 5717W, CYMEL 325 or CYMEL 327 or a combination of at least two of the same.

Preferably, the water is deionized water.

Preferably, the deionized water has a conductivity of 10. mu.s/cm or less, and may be, for example, 0.05. mu.s/cm, 0.1. mu.s/cm, 0.2. mu.s/cm, 0.4. mu.s/cm, 0.6. mu.s/cm, 0.8. mu.s/cm, 1. mu.s/cm, 2. mu.s/cm, 3. mu.s/cm, 4. mu.s/cm, 5. mu.s/cm, 6. mu.s/cm, 7. mu.s/cm, 8. mu.s/cm, 9. mu.s/cm, 10. mu.s/cm. If the conductivity of the deionized water is higher than 10 mus/cm, the storage stability of the aqueous metal protection ink of the present invention is affected due to excessive emulsification of the ink system.

Preferably, the aqueous defoamer is a non-silicon defoamer.

Preferably, the aqueous defoamer is BYK-011 and/or BYK-028.

Preferably, the aqueous leveling agent is an acrylate leveling agent.

Preferably, the aqueous leveling agent is BYK-333 and/or BYK-349.

Preferably, the aqueous coupling agent comprises any one of gamma- (2, 3-glycidoxy) propyltrimethoxysilane, gamma-aminopropylsilanetriol, a chelate of isopropyl tris (dioctyl pyrophosphato acyloxy) ethylene titanate and triethanolamine, an aminosilane hydrolysate or an epoxysilane hydrolysate, or a combination of at least two of them.

Preferably, the aqueous metal protection ink further comprises an aqueous color paste.

Preferably, the weight portion of the aqueous color paste in the aqueous metal protection ink is 1-5 parts, such as 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts, and 5 parts.

Preferably, the water-based color paste is water-based acrylic color paste.

Preferably, the color of the aqueous color paste is blue and/or black.

In a second aspect, the present invention provides a method for preparing the aqueous metal protection ink according to the first aspect, the method comprising the steps of:

(1) mixing and dispersing the water-based acrylic emulsion, the water-based epoxy resin, the methylated amino resin and water according to the formula amount to obtain a mixture;

(2) and (2) adding a water-based defoaming agent, a water-based leveling agent and a water-based coupling agent into the mixture obtained in the step (1), and dispersing to obtain the water-based metal protection ink.

Preferably, the dispersion of step (1) is carried out in a disperser.

Preferably, the dispersing time in step (1) is 10-20min, such as 10min, 11min, 12min, 13min, 14min, 15min, 16min, 17min, 18min, 19min, 20 min.

Preferably, the rotation speed of the dispersion in step (1) is 400-600rpm, and may be, for example, 400rpm, 420rpm, 440rpm, 460rpm, 480rpm, 500rpm, 520rpm, 540rpm, 560rpm, 580rpm, 600 rpm.

Preferably, the dispersion of step (2) is carried out in a disperser.

Preferably, the dispersing time in step (2) is 40-60min, such as 40min, 42min, 44min, 46min, 48min, 50min, 52min, 54min, 56min, 58min, 60 min.

Preferably, the rotation speed of the dispersion in the step (2) is 400-800rpm, and may be 400rpm, 450rpm, 500rpm, 550rpm, 600rpm, 650rpm, 700rpm, 750rpm, 800rpm, for example.

Preferably, the preparation method comprises the following steps:

(1) mixing the water-based acrylic emulsion, the water-based epoxy resin, the methylated amino resin and water according to the formula amount, and dispersing for 10-20min in a dispersion machine at the rotating speed of 400-600rpm to obtain a mixture;

(2) and (2) adding an aqueous defoaming agent, an aqueous leveling agent, an aqueous coupling agent and an aqueous color paste into the mixture obtained in the step (1), and dispersing for 40-60min in a dispersion machine at the rotating speed of 400-800rpm to obtain the aqueous metal protective ink.

Compared with the prior art, the invention has the following beneficial effects:

(1) the water-based metal protection ink disclosed by the invention is pure water-based ink with low VOC (volatile organic compounds) emission, is low in curing temperature, high in hardness after drying, high in bonding performance and good in leveling effect, high in ink adhesion fastness, scratch-resistant, good in protection, cutting fluid polishing solution-resistant and good in water resistance.

(2) The viscosity of the water-based metal protection ink is 110-140s (Ford cup 2# cup, 25 ℃), the curing temperature is 115 ℃, the VOC content is below 10 (refer to GB/T23986-2009), the adhesion force between the formed paint film and a stainless steel base material is above 5B, and the hardness of the paint film is between 3H and 4H.

Detailed Description

The technical solution of the present invention is further explained by the following embodiments. It should be understood by those skilled in the art that the examples are only for the understanding of the present invention and should not be construed as the specific limitations of the present invention.

Example 1

The embodiment provides an aqueous metal protection ink, which comprises the following components in parts by weight:

the preparation method of the aqueous metal protection ink provided by the embodiment comprises the following steps:

(1) mixing the water-based acrylic emulsion, the bisphenol A epoxy resin, the high imino methylated amino resin 5717W and deionized water according to the formula amount, and dispersing in a dispersion machine at the rotating speed of 400rpm for 20min to obtain a mixture;

(2) and (2) adding a water-based defoaming agent BYK-011, a water-based leveling agent BYK-333, gamma- (2, 3-epoxypropoxy) propyl trimethoxy silane and black water-based acrylic color paste into the mixture obtained in the step (1), and dispersing for 60min in a dispersion machine at the rotating speed of 400rpm to obtain the water-based metal protection ink.

Example 2

The embodiment provides an aqueous metal protection ink, which comprises the following components in parts by weight:

the preparation method of the aqueous metal protection ink provided by the embodiment comprises the following steps:

(1) mixing the water-based acrylic emulsion, the bisphenol F type epoxy resin, the high imino methylated amino resin CYMEL 325 and deionized water according to the formula amount, and dispersing in a dispersion machine at the rotating speed of 600rpm for 10min to obtain a mixture;

(2) and (2) adding a water-based defoaming agent BYK-028, a water-based leveling agent BYK-349, gamma-aminopropyl silane triol and blue water-based acrylic color paste into the mixture obtained in the step (1), and dispersing for 40min in a dispersion machine at the rotating speed of 800rpm to obtain the water-based metal protection ink.

Example 3

The embodiment provides an aqueous metal protection ink, which comprises the following components in parts by weight:

the preparation method of the aqueous metal protection ink provided by the embodiment comprises the following steps:

(1) mixing the water-based acrylic emulsion, the o-cresol novolac epoxy resin, the high imino methylated amino resin R-717 and deionized water according to the formula amount, and dispersing in a dispersion machine at the rotating speed of 600rpm for 10min to obtain a mixture;

(2) and (2) adding an aqueous defoaming agent BYK-028, an aqueous flatting agent BYK-349, isopropyl tris (dioctyl pyrophosphoric acyloxy) ethylene titanate and blue aqueous acrylic color paste into the mixture obtained in the step (1), and dispersing for 40min in a dispersion machine at the rotating speed of 800rpm to obtain the aqueous metal protection ink.

Example 4

This example provides an aqueous metal protection ink, which differs from example 1 only in that: the pH value of the aqueous acrylic emulsion is 6.5, and the contents of other components and the preparation method are the same as those of example 1.

Example 5

This example provides an aqueous metal protection ink, which differs from example 1 only in that: the pH value of the aqueous acrylic emulsion is 9.5, and the contents of other components and the preparation method are the same as those of example 1.

Example 6

This example provides an aqueous metal protection ink, which differs from example 1 only in that: the dynamic viscosity of the aqueous acrylic emulsion was 50mpa.s, and the contents of other components and the preparation method were the same as in example 1.

Example 7

This example provides an aqueous metal protection ink, which differs from example 1 only in that: the dynamic viscosity of the aqueous acrylic emulsion was 1500mpa.s, and the contents of other components and the preparation method were the same as in example 1.

Example 8

This example provides an aqueous metal protection ink, which differs from example 1 only in that: the curing temperature of the aqueous acrylic emulsion is 90 ℃, and the contents of other components and the preparation method are the same as those of example 1.

Example 9

This example provides an aqueous metal protection ink, which differs from example 1 only in that: the curing temperature of the aqueous acrylic emulsion is 130 ℃, and the contents of other components and the preparation method are the same as those of the example 1.

Example 10

This example provides an aqueous metal protection ink, which differs from example 1 only in that: the bisphenol A epoxy resin has a pH value of 6.5, and the contents of other components and the preparation method are the same as those of example 1.

Example 11

This example provides an aqueous metal protection ink, which differs from example 1 only in that: the bisphenol A epoxy resin has a pH value of 9.5, and the contents of other components and the preparation method are the same as those of example 1.

Example 12

This example provides an aqueous metal protection ink, which differs from example 1 only in that: the dynamic viscosity of the bisphenol a type epoxy resin was 50mpa.s, and the contents of other components and the preparation method were the same as in example 1.

Example 13

This example provides an aqueous metal protection ink, which differs from example 1 only in that: the dynamic viscosity of the bisphenol A epoxy resin is 1500mPa.s, and the contents of other components and the preparation method are the same as those of the bisphenol A epoxy resin in example 1.

Example 14

This example provides an aqueous metal protection ink, which differs from example 1 only in that: the curing temperature of the bisphenol A epoxy resin is 90 ℃, and the contents of other components and the preparation method are the same as those of the example 1.

Example 15

This example provides an aqueous metal protection ink, which differs from example 1 only in that: the curing temperature of the bisphenol A epoxy resin is 130 ℃, and the contents of other components and the preparation method are the same as those of the example 1.

Example 16

This example provides an aqueous metal protection ink, which differs from example 1 only in that: the conductivity of the deionized water is 12 mu s/cm, and the contents of other components and the preparation method are the same as those of the example 1.

Comparative example 1

This comparative example provides an aqueous ink which differs from example 1 only in that: the water-based ink does not contain high imino methylated amino resin, the content of the water-based acrylic emulsion is increased to 25.6 parts, the content of the bisphenol A epoxy resin is increased to 63.6 parts, and the content of other components and the preparation method are the same as those of example 1.

Comparative example 2

This comparative example provides an aqueous ink which differs from example 1 only in that: the water-based ink does not contain water-based epoxy resin, the content of the water-based acrylic emulsion is increased to 52 parts, the content of the high imino methylated amino resin is increased to 37.2 parts, and the content of other components and the preparation method are the same as those in example 1.

Comparative example 3

This comparative example provides an aqueous ink which differs from example 1 only in that: the water-based ink contains no water-based acrylic emulsion, the content of the bisphenol A epoxy resin is increased to 71 parts, the content of the high imino methylated amino resin is increased to 18.2 parts, and the content of other components and the preparation method are the same as those in example 1.

Comparative example 4

This comparative example provides an aqueous ink which differs from example 1 only in that: the water-based ink does not contain a water-based defoaming agent, the content of the water-based flatting agent is increased to 0.9 part, the content of the water-based coupling agent is increased to 0.9 part, and the content of other components and the preparation method are the same as those in example 1.

Comparative example 5

This comparative example provides an aqueous ink which differs from example 1 only in that: the water-based ink contains no water-based leveling agent, the content of the water-based defoaming agent is increased to 1.05 parts, the content of the water-based coupling agent is increased to 0.75 part, and the content of other components and the preparation method are the same as those of example 1.

Comparative example 6

This comparative example provides an aqueous ink which differs from example 1 only in that: the water-based ink contains no water-based coupling agent, the content of the water-based defoaming agent is increased to 1.05 parts, the content of the water-based flatting agent is increased to 0.75 part, and the content of other components and the preparation method are the same as those of example 1.

Test example 1

The viscosities (s, ford cup # 2 cup, 25 ℃) of the aqueous metal protection inks prepared in examples 1 to 16 and the aqueous inks prepared in comparative examples 1 to 6 were measured, respectively, and a paint film prepared by spraying the test sample on a stainless steel surface was measured at 115 ± 5 ℃ for 15 to 20min, and the Volatile Organic Compound (VOC), the adhesion, and the hardness of the paint film were measured, respectively, wherein: volatile Organic Compounds (VOC) are determined with reference to the method of GB/T23986-2009; the adhesive force is detected by adopting a cross-cut method; the hardness is detected by referring to a method of GB/T6739-2006; the specific test results are shown in table 1:

TABLE 1

From the above test data, it can be seen that the viscosity of the aqueous metal protective ink prepared in embodiments 1 to 16 is 110-.

While comparative examples 1-3 lack either resin, the water dispersibility of the resin system and instability in aqueous dispersion, the rheology and adhesion to the substrate of the aqueous metal protection ink decreased correspondingly. Comparative example 4 no aqueous defoamer was added and the surface had pinholes after spraying. Comparative example 5 no aqueous leveling agent was added, and oil was deposited on the surface after spraying. Comparative example 6 does not add an aqueous coupling agent, and the flow of the ink cannot be effectively hindered, and the ink adhesion is low.

Test example 2

The water-based metal protection ink prepared in the examples 1 to 16 and the water-based ink prepared in the comparative examples 1 to 6 are respectively sprayed on the surface of stainless steel to prepare a paint film, and the cutting fluid polishing fluid resistance, the water resistance, the ultrasonic cleaning resistance and the alkali dissolution time of the paint film are respectively measured at the temperature of 115 +/-5 ℃ for 15-20 min. The testing method of the cutting fluid resistant polishing solution comprises the following steps: soaking 5% of cutting fluid polishing solution at normal temperature for 24 hours; the water resistance test method comprises the following steps: soaking in tap water at normal temperature for 24 hours; the test method for ultrasonic cleaning resistance comprises the following steps: 10% of cleaning agent, the temperature is 80 ℃, the ultrasonic frequency is 50KHZ, and the time is 20 minutes; the test method of the alkali dissolution time comprises the following steps: 10% sodium hydroxide, time required at 80 ℃; the specific test results are shown in table 2:

TABLE 2

From the above test data, the water-based metal protection ink prepared in the embodiments 1 to 16 can form a paint film with cutting fluid polishing resistance of more than 24h, water resistance of more than 24h, ultrasonic cleaning resistance of more than 20min, and alkali dissolution time of less than 5 min. The fact that the components of the aqueous metal protection ink disclosed by the invention are matched with each other and have a synergistic interaction effect is fully demonstrated, and a paint film obtained by curing the prepared aqueous metal protection ink has the advantages of high adhesion with a stainless steel substrate, scratch resistance, good protectiveness, cutting fluid polishing solution resistance, good water resistance, quick alkali dissolution, safety and environmental friendliness.

The applicant states that the present invention is illustrated by the above examples to describe the aqueous metal protection ink and the preparation method thereof, but the present invention is not limited to the above examples, i.e. it does not mean that the present invention must be implemented by the above examples. It should be understood by those skilled in the art that any modification of the present invention, equivalent substitutions of the raw materials of the product of the present invention, addition of auxiliary components, selection of specific modes, etc., are within the scope and disclosure of the present invention.

Claims (21)

1. The water-based metal protection ink is characterized by comprising the following components in parts by weight: 20-25 parts of water-based acrylic emulsion, 55-60 parts of water-based epoxy resin, 5-10 parts of methylated amino resin, 5-10 parts of water, 0.5-1 part of water-based defoamer, 0.5-1 part of water-based flatting agent and 0.5-1 part of water-based coupling agent;

the pH value of the water-based acrylic emulsion is 7-9;

the dynamic viscosity of the aqueous acrylic emulsion is 100-1000 mPa.s;

the curing temperature of the aqueous acrylic emulsion is 100-120 ℃;

the solid content of the aqueous acrylic emulsion is 30-45 wt%;

the methylated amino resin is high imino methylated amino resin;

the unsealing temperature of the high imino methylated amino resin is 90-120 ℃;

the water is deionized water with the conductivity of less than 10 mu s/cm;

the pH value of the waterborne epoxy resin is 7-9;

the dynamic viscosity of the waterborne epoxy resin is 100-1000 mPa.s;

the curing temperature of the waterborne epoxy resin is 100-120 ℃.

2. The aqueous metal protection ink as claimed in claim 1, wherein the weight average molecular weight of the aqueous epoxy resin is 10000-30000.

3. The aqueous metal protection ink of claim 1, wherein the aqueous epoxy resin comprises any one of or a combination of at least two of bisphenol a type epoxy resin, bisphenol F type epoxy resin, o-cresol novolac epoxy resin, p-tert-butylphenol novolac epoxy resin, or bisphenol S type epoxy resin.

4. The aqueous metal protection ink of claim 1, wherein the highly imino methylated amino resin comprises any one of LY211, R-717, 5717W, CYMEL 325, or CYMEL 327, or a combination of at least two thereof.

5. The aqueous metal protection ink of claim 1, wherein the aqueous defoamer is a non-silicon defoamer.

6. The aqueous metal protection ink of claim 5, wherein the aqueous defoamer is BYK-011.

7. The aqueous metal protection ink according to claim 1, wherein the aqueous leveling agent is an acrylate leveling agent.

8. The aqueous metal protection ink of claim 7, wherein the aqueous leveling agent is BYK-349.

9. The aqueous metal protection ink of claim 1, wherein the aqueous coupling agent comprises any one of or a combination of at least two of gamma- (2, 3-glycidoxy) propyltrimethoxysilane, gamma-aminopropylsilanetriol, a chelate of isopropyl tris (dioctylpyrophosphate) ethylene titanate and triethanolamine, an aminosilane hydrolysate, or an epoxysilane hydrolysate.

10. The aqueous metal protection ink of claim 1, wherein the aqueous metal protection ink further comprises an aqueous color paste.

11. The aqueous metal protection ink according to claim 10, wherein the aqueous color paste is present in the aqueous metal protection ink in an amount of 1 to 5 parts by weight.

12. The aqueous metal protection ink of claim 10, wherein the aqueous color paste is an aqueous acrylic color paste.

13. The aqueous metal protection ink according to claim 10, wherein the aqueous color paste is blue and/or black in color.

14. Method for preparing an aqueous metal protection ink according to any one of claims 1 to 13, characterized in that it comprises the following steps:

(1) mixing and dispersing the water-based acrylic emulsion, the water-based epoxy resin, the high imino methylated amino resin and water according to the formula amount to obtain a mixture;

(2) and (2) adding a water-based defoaming agent, a water-based leveling agent and a water-based coupling agent into the mixture obtained in the step (1), and dispersing to obtain the water-based metal protection ink.

15. The production method according to claim 14, wherein the dispersion of step (1) is carried out in a disperser.

16. The method according to claim 14, wherein the dispersing time in the step (1) is 10 to 20 min.

17. The method as claimed in claim 14, wherein the rotation speed of the dispersion in step (1) is 400-600 rpm.

18. The production method according to claim 14, wherein the dispersion of step (2) is carried out in a disperser.

19. The method according to claim 14, wherein the dispersing time in the step (2) is 40 to 60 min.

20. The method as claimed in claim 14, wherein the rotation speed of the dispersion in the step (2) is 400-800 rpm.

21. The method of manufacturing according to claim 14, comprising the steps of:

(1) mixing the water-based acrylic emulsion, the water-based epoxy resin, the high imino methylated amino resin and water according to the formula amount, and dispersing for 10-20min in a dispersion machine at the rotating speed of 400-600rpm to obtain a mixture;

(2) and (2) adding an aqueous defoaming agent, an aqueous leveling agent, an aqueous coupling agent and an aqueous color paste into the mixture obtained in the step (1), and dispersing for 40-60min in a dispersion machine at the rotating speed of 400-800rpm to obtain the aqueous metal protective ink.