CN106189472B

CN106189472B - Compound whitening slurry and interior wall latex paint using same

Info

Publication number: CN106189472B
Application number: CN201610560102.8A
Authority: CN
Inventors: 何健; 高孝麟
Original assignee: Yashili Coatings (suzhou) Co Ltd
Current assignee: Yashili Coatings (suzhou) Co Ltd
Priority date: 2016-07-15
Filing date: 2016-07-15
Publication date: 2019-12-10
Anticipated expiration: 2036-07-15
Also published as: CN106189472A

Abstract

The invention provides a compound whitening slurry and an interior wall latex paint using the same, wherein the compound whitening slurry comprises the following components in percentage by mass: 6.0% of whitening agent; 1.5 percent of hydroxyethyl cellulose; 5.4 to 6.6 percent of SN-5040 sodium polycarboxylate surfactant; 85.9 to 87.1 percent of pure water. The interior wall latex paint disclosed by the invention uses the multi-step compounded whitening slurry, overcomes the defect of poor whitening effect when the whitening agent is singly used in the original latex paint, further plays the role of the whitening agent and reduces the unit cost. And other components of the coating are not changed, so that the main performance of the coating is not changed, other requirements are not changed, the coating meets all indexes in GB/T9756-2009 standard, and the limit of harmful substances in the inner wall coating of GB/18582-. Compared with the common water-based paint, the invention has lower raw material cost when the same whiteness is improved, and has stronger product competitiveness and wide market prospect.

Description

compound whitening slurry and interior wall latex paint using same

Technical Field

The invention relates to the technical field of decorative coatings, in particular to a compound whitening slurry and an interior wall latex paint using the same.

Technical Field

The first book of relatively authoritative coating processes in the Chinese coating world is defined as follows: the paint is a material which can be coated on the surface of an object by different construction processes to form a continuous solid film with firm adhesion and certain strength. The film thus formed is generally called a coating film, also called a paint film or a coating. "Water-based interior wall latex paint as a decorative material must have good decorativeness and environmental protection, including whiteness index. Overview of whiteness of latex paints: the CIELAB system formulated by CIE is the current international universal color measurement standard, and China derives the standard to form Wb whiteness used in the current latex paint field. The whiteness integrates two factors of color tone and brightness, and the whiteness becomes an important value component of the interior wall latex paint.

titanium dioxide is currently known as the best white pigment in the world, and the reason for generating whiteness is that the titanium dioxide has high refractive index and covering property. Two crystal forms of titanium dioxide are commonly used in coatings: the rutile titanium white has high cost and higher refractive index and covering power; the anatase titanium dioxide has low cost and better same-diameter short-wave reflection effect than rutile, but the anatase titanium dioxide is gradually eliminated by society due to large pollution and unstable crystal form in the production process, and partial substitution of the anatase has adverse effects on the overall performance, the luster and the like.

The whiteness of the economic latex paint is generally not very high, and the efficiency is low and the cost is high simply by improving the titanium white. Therefore, a method for improving the whiteness of the interior wall latex paint, which is non-titanium white, more efficient, environment-friendly and low in cost, is to be found. The development of the method is bound to win the opportunity for enterprises in the red sea game.

The invention specifically comprises the following contents:

One object of the present invention is to provide a compounded whitening slurry and an interior wall latex paint using the same, so that the whiteness of the interior wall paint can be increased to more than 92%.

In order to achieve the purpose, the specific technical scheme of the invention is as follows:

The compound whitening slurry is characterized by comprising the following components in percentage by mass:

Preferably, the whitening agent is UV 05- [ 2,2' - (1, 2-ethenediyl) bis [5- [ [4- [ bis (2-hydroxypropyl) amino ] -6- [ (4-sulfophenyl) amino ] -1,3, 5-triazin-2-ethyl ] amine ] benzenesulfonic acid sodium salt.

The preparation method of the compound whitening slurry is characterized by firstly adding the whitening agent into pure water, stirring and dispersing at a low speed for 5 minutes, then adding the hydroxyethyl cellulose for fully mixing at a low speed, dropwise adding the SN-5040 sodium polycarboxylate surfactant at a low speed after fully and uniformly mixing, and stirring uniformly to form the compound whitening slurry.

the interior wall latex paint using the compound whitening slurry is characterized by comprising the following components in percentage by mass:

The auxiliary material comprises the following components

3.5 to 10 percent of calcined kaolin

30 to 45 percent of calcium carbonate

0 to 10 percent of aluminum silicate.

All raw materials used in the interior wall coating are mainly water-based coating components, are easy to obtain in the market and are low in cost.

The preparation method of the interior wall latex paint is characterized by comprising the following steps:

(1) premixing: accurately adding pure water, accurately adding the cellulose thickener under stirring at a rotating speed of 400-600 revolutions per minute, and fully stirring until the mixture is completely swelled; accurately adding a dispersing agent, and uniformly stirring; accurately adding rutile type titanium dioxide and auxiliary materials in turn during stirring, adjusting the rotating speed to 1200-1600 rpm after the feeding amount accounts for 2/3 of the total powder amount, and stirring for 15-20 minutes at the feeding speed which is suitable for preventing powder from accumulating;

(2) And (3) diluting: adjusting the rotating speed to 500-800 r/min, sequentially adding a film forming agent, a defoaming agent and a mildew preventive, finally adding the compound whitening slurry, and fully and uniformly stirring; adding the latter auxiliary agent after the former auxiliary agent is uniformly stirred, and finally stirring for 5-10 minutes to obtain the interior wall latex paint;

in the whole preparation process, the temperature of the system is kept between 20 ℃ and 45 ℃.

Description of the inventive principle:

Firstly, the whitening agent is added into the common styrene-acrylic emulsion paint for the interior wall according to different proportions, and the function of increasing the whiteness of a dry film is achieved under the condition that the covering power of the original emulsion paint is not changed. Whitening agents are of a wide variety of types, but they can be roughly classified into 6 types: 1) stilbenes; 2) benzoxazoles; 3) coumarins; 4) bis-oxazinamines; 5) pyrazolines; 6) phthalimides. The representative marks in the above categories are as follows: stilbene ER grades have obvious formaldehyde residues in the synthesis process, have great influence on coating VOC, the sublimation fastness of benzoxazole DT grades is not good, the secondary pollution to the home environment is also caused, and the health is endangered, coumarin SWN grades, pyrazoline AD grades and phthalimide APL grades are mainly used for textile finishing and dyeing processes and are insoluble in water, coumarin ANB grades are used for a coating system and can generate serious flocculation, and the research on the stilbene VBL grades and the CXT grades proves that the stilbene ER DT grades and the phthalimide APL grades have direct carcinogenicity. Stilbenes are used as a large class of water-soluble whitening agents and are mainly used in the production processes of papermaking, coating and soap making. Through preliminary screening, experiments with water-soluble stilbenes and benzoxazoles are finally determined.

table 1: the proportion of the whitening agent added to the new formula and the change of whiteness are shown in the table:

from table 1, it can be seen that: since the dispersion of the solid brightener in the latex paint system is reduced with the increase of the amount of the solid brightener, it can be seen from the table that when the amount of the CBS-X brightener and the OB-1 brightener exceeds 2.0 per thousand, the dry film coating has uneven bright spots, and the whitening effect is not as good as that of the liquid brightener. When the addition amount of the liquid whitening agent is more than 8 per mill, the whitening efficiency is obviously deteriorated.

TABLE 2 Effect of liquid brighteners on viscosity of reformulated latex paint systems

as can be seen from Table 2: when the addition amount of the liquid brightener exceeds 6 per thousand in the online addition process, the viscosity is extremely increased, the construction hand feeling brushing experiment is obviously poor, and the influence of an anionic brightener such as a brightener APC (ammonium sulfate phosphate) on the viscosity of a system is very large, so that the brightener UV 05- [ 2,2' - (1, 2-ethenediyl) bis [5- [ [4- [ bis (2-hydroxypropyl) amino ] -6- [ (4-sulfophenyl) amino ] -1,3, 5-triazine-2-ethyl ] amine ] benzenesulfonic acid sodium salt ] is finally selected for carrying out a series of experiments. The whitening agent is Lewis base which is easy to dissolve in water, electrons which can freely move at two ends of a large pi bond can be reduced under the action of ultraviolet illumination, and jump outwards to form blue-violet light with lower energy, thereby offsetting the action of part of yellow light and improving the dry film whiteness of the emulsion paint. The carbon chain structure has a specific gravity of 1.10 to 1.20 and a pH of 8.0 to 10.0 at room temperature. Gradient experiments were performed to determine the whitening effect of the whitening agent with the selected UV05 whitening agent.

the UV05 is used as a 4-sulfonic acid group whitening agent, the fluorescence intensity is not strong, and the phenomenon of green change or even grey change can not be generated when the whitening agent is excessively added, although the whiteness of the experimental formula can be improved from 86.32% to 88.19% after the UV05 is added according to 6 per mill in the experiment, the whiteness of the UV05 is improved by 1.87%, and the whiteness of the experimental sample is still greatly different from the whiteness of 92% of the target whiteness.

Secondly, after the factors of whitening effect, construction hand feeling and viscosity are fully considered, the dispersion sufficiency is taken as an experimental variable, and the better dispersion and adhesion are attempted through the loading of the whitening agent and the cellulose. The whitening agent is anionic, so that the whitening agent can be well dispersed in the solution, and the whitening agent is better adsorbed on the surface of cellulose due to the polarity attraction of functional groups on the surface of the cellulose. When the whitening agent is added in the preceding stage, there is more chance of adequate binding with the cellulose and longer dispersion time. At this point we performed a loading compounding experiment of whitener with different concentrations of cellulose.

The process is as follows: the whitening agent is preferentially added into pure water, the mixture is stirred and dispersed at a low speed, and then cellulose is added to be fully mixed and dispersed to form the compound cellulose high-white slurry.

Firstly, a preliminary experiment shows that the compound formula 1 is as follows (in percentage by mass):

pure water: 92% -93%;

whitening agent: 6 percent;

hydroxyethyl cellulose: 1% -2%;

By adding 10% of the 1# compound slurry in the front section and 6% of the whitening agent in the rear section, equivalent addition contrast is formed.

TABLE 3 Experimental tables in the new formula of viscosity before and after compounding of whitening agent

As can be seen from Table 3: obviously, the whiteness is slightly improved by the measures, the dispersion and the attachment are really improved in the front section, when the addition amount of the cellulose is less than 1.5%, the amount is too small, the attachment influence on the whitening agent is very little, and when the consumption amount of the cellulose is more than or equal to 1.5%, the whiteness is slightly improved. The beneficial loading was determined to be 1.5% and the specific increments were also designed based on the overall viscosity of the system. Probably along with the addition of the auxiliary materials, the di-trivalent metal ions hydrolyzed by the auxiliary materials poison the free whitening agent and weaken the improvement effect of the free whitening agent.

Thirdly, in consideration of the above factors, we try to combine the free whitening agent with the anionic surfactant to form a cell structure, so as to protect the high-valence metal ions dissolved out from the later powder after the later powder is added from poisoning the dispersion, and the high-valence metal ions are mutually exclusive and stably dispersed under the action of the same anionic groups. The surfactant is added into the system for compounding, and the maximum dispersion of the fluorescent whitening agent is achieved through two-step compounding.

The process is as follows: the whitening agent is preferentially added into pure water, the mixture is stirred and dispersed at a low speed, then cellulose is added, the mixture is dispersed and mixed fully at a low speed, and finally SN-5040 polycarboxylate surfactant is dropwise added at a low speed until the mixture is stirred uniformly to form the compound cellulose high-white slurry.

Further experiments show that the compound formula 2 comprises the following components (by mass percent):

pure water: 83.5 to 93.5 percent;

Whitening agent: 6 percent;

hydroxyethyl cellulose: 1.5 percent;

SN-5040 surfactant: 0 to 9 percent.

TABLE 5 SN-5040 different proportions of compounded size used for whiteness table of whitening agent with new formulation No. 1 and same parts

As can be seen from Table 5: experiments show that when the ratio of the whitening agent to the surfactant is less than 1:1.1, a large amount of surfactant is continuously added, not only can the whitening agent be better protected, but also the fluorescence reduction effect can be generated, so that the whitening agent with a planar configuration is grafted into excessive surfactant, the activity of large pi bonds of the surfactant is reduced, and a large amount of free molecules are coated and cannot be combined with cellulose. The dispersion is not enough to ensure the effect of the dispersion in powder and latex paint, and because the powder can be partially stably broken in later stage of dispersion, the system can really achieve the maximization of stable whitening and whitening efficiency only when the dosage of the surfactant reaches dynamic balance in the dispersion and agglomeration effects. When the ratio of the whitening agent to the surfactant is 1: 0.9-1: 1.1, the interior wall formula has good whiteness.

The final formulation was as follows:

Pure water: 85.9 to 87.1 percent;

Whitening agent: 6.0 percent;

hydroxyethyl cellulose: 1.5 percent;

Polycarboxylic acid sodium salt surfactant: 5.4-6.6%.

The compounding process comprises the following steps: the whitening agent is preferentially added into pure water, the mixture is stirred and dispersed at a low speed for 5 minutes, then cellulose is added, dispersed and fully mixed at a low speed, and SN-5040 polycarboxylate surfactant is dropwise added at a low speed after the mixture is fully mixed, until the mixture is uniformly stirred, so that the compound cellulose high-white slurry is formed.

review the mechanism of the present invention to improve whiteness: the whitening agent is introduced, the whole whiteness is improved through reflection and emission of short-wave near ultraviolet light rays of rutile titanium dioxide, the loading attachment and front-section dispersity improvement of the whitening agent are improved through various modes, the coating protection effect of the surfactant micelle on the free whitening agent is improved, and the whitening effect is jointly improved in the emulsion paint. The composite formula formed by the whitening agent is prepared by the composite whitening slurry of cellulose and surfactant, and finally the whiteness of the interior wall formula is up to more than 92% by the scheme of optimal cost performance.

the invention has the advantages that: the other raw materials are mainly water-based paint components, are easy to obtain in the market and have low cost. The whitening agent is less than 6 per mill, and the whiteness of the common interior wall latex paint can be improved to more than 92 percent by compounding a series of common materials and additives.

has the advantages that:

The interior wall latex paint disclosed by the invention innovatively uses multi-step compounded whitening slurry, overcomes the defect of poor whitening effect when the whitening agent is singly used in the original latex paint, further plays the role of the whitening agent and reduces the unit cost. And other components of the coating are not changed, so that the main performance of the coating is not changed, other requirements are not changed, the coating meets all indexes in GB/T9756-2009 standard, and the limit of harmful substances in the inner wall coating of GB/18582-. Compared with the common water-based paint, the invention has lower raw material cost when the same whiteness is improved, and has stronger product competitiveness and wide market prospect.

the specific implementation mode is as follows:

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

examples

1. interior wall latex paint example 1 had the following composition (in mass percent):

The auxiliary materials comprise the following components:

Calcined kaolin 4.9%

43.1 percent of calcium carbonate

2. Interior wall latex paint example 2 had the following composition (in mass percent):

the auxiliary materials comprise the following components

calcined kaolin 12%

Calcium carbonate 25%

2.2 percent of aluminum silicate

3. Interior wall latex paint example 3 had the following composition (in mass percent):

the auxiliary materials comprise the following components

calcined kaolin 8%

20 percent of calcium carbonate

3.8 percent of aluminum silicate

4. The components of the inner wall latex paint comparative example are as follows (in mass percent)

The auxiliary materials comprise the following components:

Calcined kaolin 4.9%

43.1 percent of calcium carbonate.

The experimental results are as follows:

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and all such modifications, equivalents and improvements that come within the spirit and scope of the invention are therefore intended to be included therein. It is intended that the invention be limited in any way so that any modification or variation of the invention herein disclosed which comes within the spirit of the invention is encompassed by the invention as hereinafter claimed.

Claims

1. The compound whitening slurry is characterized by comprising the following components in percentage by mass:

The whitening agent is UV 05- [ 2,2' - (1, 2-ethenediyl) bis [5- [ [4- [ bis (2-hydroxypropyl) amino ] -6- [ (4-sulfophenyl) amino ] -1,3, 5-triazine-2-ethyl ] amine ] benzenesulfonic acid sodium salt.

2. the preparation method of the compound whitening slurry according to claim 1, characterized in that the whitening agent is added into pure water and stirred at a low speed for 5 minutes, then the hydroxyethyl cellulose is added for fully mixing after being dispersed at a low speed, and SN-5040 sodium polycarboxylate surfactant is dropwise added at a low speed after being fully mixed until the compound whitening slurry is uniformly stirred to form the compound whitening slurry.

3. an interior wall latex paint using the compound whitening slurry of claim 1, which is characterized by comprising the following components in percentage by mass:

The auxiliary material comprises the following components in percentage by mass, the sum of the mass percentages of the components is not more than 48 percent,

3.5 to 10 percent of calcined kaolin

30 to 45 percent of calcium carbonate

0 to 10 percent of aluminum silicate.