CN108117786B - Water-based zinc-rich shop primer for roll coating and preparation method thereof - Google Patents

Abstract

The invention discloses a water-based zinc-rich shop primer for roll coating and a preparation method thereof, wherein the water-based zinc-rich shop primer comprises 20-25 wt% of water-based resin, 2-3 wt% of dispersing agent, 0.1-0.5 wt% of wetting agent, 0.1-0.5 wt% of defoaming agent, 3-5 wt% of active aid slurry, 2-4 wt% of heavy metal powder and 62-70 wt% of zinc powder, all the raw materials are stirred and mixed uniformly, and then the mixture is filtered through a 100-mesh filter screen, and then the viscosity is adjusted by water to obtain the water-based zinc-rich shop primer. The water-based zinc-rich shop primer for roller coating can solve the problems of poor rheological property, loose and layered zinc powder, uneven zinc powder distribution, poor coating spreading property, poor and uneven electro-optic wheel adsorption coating, poor wettability of coating and substrate and powder-liquid separation of zinc powder sedimentation of the conventional water-based zinc-rich coating, and is completely suitable for a roller coating process.

Description

Water-based zinc-rich shop primer for roll coating and preparation method thereof

Technical Field

The invention relates to a water-based zinc-rich shop primer for roll coating and a preparation method thereof, belonging to the field of chemical paint.

Background

In 2007, a centralized group firstly starts to test and use a pretreatment roller coating construction process of a container steel plate, and then in a few years, the process is popularized and used by a plurality of manufacturers in the container industry, and until now, the two-component epoxy zinc-rich primer is used as a shop primer for pre-coating the steel plate, and becomes a very mature process. In 2017, the domestic environmental protection pressure is getting worse, the oil-to-water and full-water in the coating industry have to be promoted, and in the current process, a solvent type two-component epoxy zinc-rich primer used as a workshop primer is prohibited from being used in a centralized group from 4 months and 1 days in 2017. Therefore, a pure water zinc-rich primer suitable for the roller coating process becomes a necessary choice for the market. Paint manufacturers such as Dewei, China and abroad Guanxi, Weishibo, Shi and the like successively try roller coating experiments by using water-based zinc-rich as shop primers, but have more or less disadvantages: the coating thickness can not be kept stable, the drying time can not meet the requirements of a customer production line, the coating has poor spreading performance and uniformity, flash rust appears, rust spots appear in the time required by placement, and the like. The problems limit the popularization and development of the waterborne zinc-rich primer as a shop primer in the aspect of pretreatment process of the container steel plate, and restrict the pretreatment of the container steel plate to be a waterborne process.

Disclosure of Invention

The purpose of the invention is as follows: the invention aims to solve the technical problem of the prior art and provides a water-based zinc-rich shop primer capable of adopting a roller coating process and used for a container and a preparation method thereof.

In order to solve the technical problem, the invention discloses a water-based zinc-rich shop primer for roll coating, which comprises the following components in percentage by weight:

further, the water-based zinc-rich shop primer for roller coating preferably comprises the following components in percentage by weight:

the water-based resin is inorganic silicate modified water-based zinc-rich special resin, and is preferably a HW-100 water-based resin product which is purchased from Wuxi Euro Germany chemical industry Co.

The dispersant is a modified polyacrylate polymer, preferably a 4560 dispersant product available from Effkona adjuvant (Jiangsu) Co., Ltd.

The wetting agent is purchased from TEGO @ Co high adjuvant and is 4100 in model number.

The defoamer was purchased from affkona adjuvant (jiangsu) ltd and has a model number PD 524.

The coagent slurry was purchased from Wuxi Huhuang Lacquer Co., Ltd, and was HW-101M in model.

The heavy metal stone powder is purchased from Heshan chemical industry (Huzhou) Co., Ltd, and has the model of SM-K100.

The zinc powder is 500 meshes and is purchased from Yangzhou Shuangsheng zinc industry Co.

The invention also provides a preparation method of the water-based zinc-rich shop primer for roller coating, which comprises the following steps:

the method comprises the following steps: mixing the water-based resin, the dispersing agent, the wetting agent and the defoaming agent, and uniformly stirring;

step two: adding the active auxiliary agent slurry into the mixture obtained in the step one under the stirring state, and continuously dispersing until the fineness of the mixture is less than or equal to 10 mu m;

step three: adding the heavy metal stone powder and the zinc powder into the mixture obtained in the step two, and continuously stirring and uniformly mixing;

step four: sieving the material obtained in the step three by a 100-mesh filter screen to obtain a master batch;

step five: and D, adjusting the viscosity of the master batch obtained in the step four by using water to obtain the master batch.

For containers, shop primers are a precoating protective coating that, in addition to all the properties of a water-borne zinc-rich primer, requires a dry film thickness of no more than 10 μm (or as thin as possible while ensuring all the properties), has good flash rust resistance, good cutting and welding properties, and at the same time, has good corrosion resistance at low film thicknesses. The Euromdell water-based zinc-rich resin used in the formula of the water-based zinc-rich workshop primer for roller coating is a product specially developed for roller coating, and can be matched with the active assistant slurry to achieve the purposes of ensuring that a paint film is uniform and does not leak during roller coating, ensuring that the thickness of a dried film of a precoating layer reaches 7 mu m, and having good welding and cutting performances. The Europa waterborne zinc-rich resin has the characteristics of excellent wetting property, high drying speed and good adhesive force, and mainly ensures the drying speed and the adhesive force of a coating. The active assistant slurry can enable the resin and the antirust and anticorrosive powder to form a uniform system, so that the resin and the antirust and anticorrosive powder can be uniformly adsorbed and spread on the surfaces of the roller wheel and the electro-optic wheel in the roller coating process to form an uninterrupted continuous phase, the defect that the coating is difficult to spread uniformly on the roller and the electro-optic wheel due to thinness is solved, and the film forming thickness of a dry film is finally ensured. The active additive slurry has the advantages of micro-charge adsorption, super-strong uniform powder spreading performance and thixotropic property to a system, and finally ensures the possibility of roller coating and various physical and chemical properties of subsequent coating.

Has the advantages that:

1. the water-based zinc-rich shop primer adopts the special active assistant slurry matched with the water-based zinc-rich resin, can solve the problems of poor rheological property, loose and layered zinc powder, uneven zinc powder distribution, poor coating spreading performance, poor and uneven electro-optic wheel adsorption coating, poor wettability of the coating and a substrate and powder-liquid separation of zinc powder sedimentation of the conventional water-based zinc-rich coating, and is completely suitable for a roller coating process.

2. The thickness of a dry film obtained by the water-based zinc-rich workshop primer through a roller coating process can be controlled within the range of 7-10 microns, the coating is dried at 35 ℃ for 2 minutes, no flash rust occurs on the whole coating, the whole coating is observed by a 15-time magnifying glass, the whole coating is free of missing coating, a coating piece is naturally placed indoors for 30 days, no rust point occurs, the interlayer adhesive force with a subsequent coating is excellent, and the construction is barrier-free.

3. The water-based zinc-rich shop primer can be coated in a roller coating mode, so that the assembly line production of the container is facilitated.

Detailed Description

The invention will be better understood from the following examples.

The following are the starting materials used in the examples:

aqueous resin HW-100, available from Stannless Euromand chemical; dispersant AFCONA 4560, available from affkona adjuvant (jiangsu) ltd; wetting agent DG 4100, purchased from diyao high adjuvant; antifoam AFCONA PD524, available from affkona adjuvant (jiang su) ltd; coagent slurry HW-101M, available from Wuxi Huhuang Lacquer Co., Ltd; heavy gold stone powder SM-K100, Heishan chemical (Huzhou) Co., Ltd; zinc powder 500 mesh, Yangzhou Shuangsheng zinc Co., Ltd.

Example 1

The formula comprises the following components in percentage by weight:

the preparation method comprises the following steps:

the method comprises the following steps: adding the water-based resin, the dispersing agent, the wetting agent and the defoaming agent into a drawn cylinder, mixing, dispersing for 10 minutes at 500-600 rpm, and uniformly stirring;

step two: slowly adding the active auxiliary agent slurry into the mixture obtained in the step one under the stirring state of 500 revolutions per minute, and continuously dispersing at 800 revolutions per minute until the fineness of the mixture is less than or equal to 10 mu m;

step three: adding the heavy metal stone powder and the zinc powder into the mixture obtained in the step two, dispersing for 10 minutes at 800 rpm, and continuously stirring and uniformly mixing;

step four: sieving the material obtained in the step three by a 100-mesh filter screen to obtain a master batch;

step five: and (5) adjusting the viscosity of the master batch obtained in the step four by using water until the slurry flows out of the rock field cup for 18 +/-2 seconds, thus obtaining the cement.

Example 2

The formula comprises the following components in percentage by weight:

the specific preparation method is the same as that of example 1.

Example 3

The formula comprises the following components in percentage by weight:

the specific preparation method is the same as that of example 1.

Example 4

The formula comprises the following components in percentage by weight:

the specific preparation method is the same as that of example 1.

Table 1 shows the performance tests of the waterborne zinc rich shop primers prepared in examples 1-4. Wherein, a polyurethane foaming type soft roller with a net sleeved on the surface is adopted for roller coating, and the surface drying time adopts a surface drying and middle drying method in GB/T1728-1979; the adhesion force is specified in GB/T9826; the flash rust condition is that whether yellow rust spots appear on the surface of the coating film after the roller coating surface is dried or not and whether the yellow rust spots appear on the surface of the coating film after the coating film is naturally placed for 7 days or not; the dry film thickness was measured after natural standing for 48 hours according to the film thickness. As can be seen from the data in the table: the water-based zinc-rich shop primer can solve the problems of poor rheological property, loose and layered zinc powder, uneven zinc powder distribution, poor coating spreading performance, poor and uneven adsorption of the coating by an electro-optic wheel, poor wettability of the coating and a substrate and powder-liquid separation of zinc powder sedimentation of the conventional water-based zinc-rich coating.

TABLE 1

Performance of	Example 1	Example 2	Example 3	Example 4
					Surface drying time (35 ℃)/s	120	125	118	116
Adhesive force (scribing lattice)	Level 0	Level 0	Level 0	Level 0
					Flash rust condition	No flash rust	No flash rust	No flash rust	No flash rust
Dry film thickness-μm	7	10	8	8
					Condition of the coating	Uniform surface without leakage points	Uniform surface without leakage points	Uniform surface without leakage points	Uniform surface without leakage points
Indoor placement	No rust spot for 30 days	No rust spot for 30 days	No rust spot for 30 days	No rust spot for 30 days
					Settling property	No sedimentation in 3 hours	No sedimentation in 3 hours	No sedimentation in 3 hours	No sedimentation in 3 hours
Interlayer adhesion	Is excellent in	Is excellent in	Is excellent in	Is excellent in

The present invention provides a water-based zinc-rich shop primer for roll coating and a method for preparing the same, and a plurality of methods and ways for implementing the technical scheme are provided, the above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of improvements and embellishments can be made without departing from the principle of the present invention, and the improvements and embellishments should be regarded as the protection scope of the present invention. All the components not specified in the present embodiment can be realized by the prior art.

Claims (3)

1. The water-based zinc-rich shop primer for roll coating is characterized by comprising the following components in percentage by weight:

wherein the water-based resin is inorganic silicate modified water-based zinc-rich special resin which is purchased from Jiangsu Euromand technology Limited and has the model of HW-100;

the dispersant is a modified polyacrylate polymer;

the dispersing agent is purchased from Effkona auxiliary agent company Limited, and the model number is 4560;

the active assistant slurry is purchased from Tiger Royal lacquer industry Co., Ltd in Wuxi city, and the model is HW-101M;

the heavy metal stone powder is purchased from Heshan chemical industry Co., Ltd, and has the model of SM-K100;

the zinc powder is 500 meshes.

2. The water-based zinc-rich shop primer for roll coating according to claim 1, which comprises the following components in percentage by weight:

3. the method for preparing the water-based zinc rich shop primer for roll coating as claimed in claim 1 or 2, comprising the steps of:

the method comprises the following steps: mixing the water-based resin, the dispersing agent, the wetting agent and the defoaming agent, and uniformly stirring;

step two: adding the active auxiliary agent slurry into the mixture obtained in the step one under the stirring state, and continuously dispersing until the fineness of the mixture is less than or equal to 10 mu m;

step three: adding the heavy metal stone powder and the zinc powder into the mixture obtained in the step two, and continuously stirring and uniformly mixing;

step four: sieving the material obtained in the step three by a 100-mesh filter screen to obtain a master batch;

step five: and D, adjusting the viscosity of the master batch obtained in the step four by using water to obtain the master batch.