Colored facing mortar and preparation method thereof

Abstract

The invention discloses colored facing mortar and a preparation method thereof, and relates to the technical field of facing mortar, the colored facing mortar comprises the following components by weight: 20-30 parts of cement; 40 to 60 parts by weight of sand; 0.2 to 1 part by weight of latex powder; 0.3 to 0.5 part by weight of cellulose ether; 0-3 parts by weight of a reinforcing agent; 1-5 parts of an inorganic pigment; and 0.5-3 parts by weight of an efflorescence inhibitor. According to the technical scheme provided by the invention, the compressive strength of the colored facing mortar is improved while the saltpetering of the colored facing mortar is inhibited.

Description

Technical Field

[0001] The invention relates to the technical field of facing mortar, and in particular to a colored facing mortar and a preparation method thereof. Background Art

[0002] Colored facing mortar, also known as colored decorative mortar or cement-based colorful decorative powder, is a new type of environmentally friendly decorative material. In developed countries, it has been widely used to replace paint and tiles for interior and exterior wall decoration of buildings, meeting the development trend of "safety, environmental protection and energy saving". Colored facing mortar has the following advantages: (1) Environmentally friendly and non-toxic: The raw materials of colored facing mortar are mainly natural mineral materials, which do not contain volatile organic compounds such as free formaldehyde and benzene, are non-toxic and odorless, and are green and environmentally friendly. (2) Rich colors: The colors are simple and decorative, and can meet the decorative effects of different styles and different needs. (3) Excellent performance: It has good air permeability and hydrophobicity, and can form a colorful exterior wall decoration system with breathing function, which has significant moisture-proof and anti-seepage effects. It has excellent alkali resistance, pollution resistance and impact resistance, and a long service life of more than 20 years. It has good elasticity and low shrinkage, and is not easy to crack after painting.

[0003] The efflorescence of cement-based materials often has a serious impact on colored finishing mortars. Efflorescence usually forms white salt deposits on the surface of colored finishing mortars. These deposits are in sharp contrast with the original color of the mortar, thus destroying the overall decorative effect of the mortar. Especially when the color of the colored mortar is darker, the white spots formed on the surface will be more obvious, seriously affecting the aesthetics of the building, and even causing the mortar to crack, fall off and other problems during use. At present, the efflorescence treatment processes mainly include acid washing, sandblasting, etc., which will inevitably cause damage to the concrete surface. For this reason, internally added efflorescence inhibitors have appeared on the market. Most of these efflorescence inhibitors are organic components. While inhibiting efflorescence to a certain extent, they will also reduce the compressive strength of the finishing mortar. Summary of the invention

[0004] The main purpose of the present invention is to provide a colored facing mortar and a preparation method thereof, aiming to inhibit efflorescence of the colored facing mortar while improving the compressive strength of the colored facing mortar.

[0005] To achieve the above object, the present invention provides a colored facing mortar, which comprises, by weight:

[0006] 20 to 30 parts by weight of cement;

[0007] 40-60 parts by weight of sand;

[0008] 0.2-1 parts by weight of latex powder;

[0009] 0.3-0.5 parts by weight of cellulose ether;

[0010] 0 to 3 parts by weight of a reinforcing agent;

[0011] 1-5 parts by weight of an inorganic pigment; and,

[0012] 0.5 to 3 parts by weight of efflorescence inhibitor.

[0013] In one embodiment, the enhancer comprises cupric chloride dihydrate.

[0014] In one embodiment, the efflorescence inhibitor includes one or any combination of magnesium chloride, zinc chloride, aluminum chloride and polyaluminum chloride.

[0015] In one embodiment, the inorganic pigment includes an iron-based inorganic pigment.

[0016] In one embodiment, the latex powder includes a copolymer of two or three of vinyl acetate, ethylene and acrylic acid.

[0017] In one embodiment, the cellulose ether includes one or two of methyl cellulose ether, hydroxypropyl cellulose ether, hydroxypropyl starch ether and hydroxymethyl starch ether.

[0018] The present invention also provides a method for preparing a colored facing mortar, wherein the colored facing mortar comprises the following components in parts by weight:

[0019] 20 to 30 parts by weight of cement;

[0020] 40-60 parts by weight of sand;

[0021] 0.2-1 parts by weight of latex powder;

[0022] 0.3-0.5 parts by weight of cellulose ether;

[0023] 0 to 3 parts by weight of a reinforcing agent;

[0024] 1-5 parts by weight of an inorganic pigment; and,

[0025] 0.5 to 3 parts by weight of an efflorescence inhibitor;

[0026] The preparation method of the colored facing mortar comprises the following steps:

[0027] Mixing and stirring the various components of the color finishing mortar for the first time to obtain a dry powder color finishing mortar;

[0028] The dry powder colored finishing mortar is added with water and mixed and stirred for a second time to obtain the colored decorative mortar.

[0029] In one embodiment, the first mixing and stirring time is 10 to 15 minutes; and / or,

[0030] The second mixing and stirring time is 1.5 to 2.5 minutes; and / or,

[0031] The step of adding water to the dry powder color finishing mortar for a second mixing and stirring specifically includes: adding the dry powder color finishing mortar into water in small amounts for a second mixing and stirring.

[0032] In the technical solution of the present invention, cement is used to provide strength and durability to the colored facing mortar after hardening; sand is used to increase the volume of the mortar and help control the shrinkage and expansion of the colored facing mortar; cellulose ether can thicken the colored facing mortar and improve the water retention of the colored facing mortar; the efflorescence inhibitor can reduce the phenomenon of salt deposition on the surface caused by water evaporation (i.e., efflorescence) to maintain the beauty of the finish; the inorganic pigment has excellent color stability and weather resistance, and can maintain bright colors when exposed to the natural environment for a long time; the enhancer promotes the colored facing mortar to form a tighter particle arrangement, improves the internal density, and thus improves the compressive strength. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0034] Figure 1 A sample picture of Example 1 of the colored facing mortar provided by the present invention;

[0035] Figure 2 This is a sample picture of Example 3 of the colored facing mortar provided by the present invention;

[0036] Figure 3 This is a sample picture of Comparative Example 5 of the colored facing mortar provided by the present invention;

[0037] Figure 4 This is an electron microscope image of the sample of Example 5 of the colored facing mortar provided by the present invention;

[0038] Figure 5 This is an electron microscope image of the sample of Comparative Example 5 of the colored finishing mortar provided by the present invention.

[0039] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0042] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0043] Colored facing mortar, also known as colored decorative mortar or cement-based colorful decorative powder, is a new type of environmentally friendly decorative material. In developed countries, it has been widely used to replace paint and tiles for interior and exterior wall decoration of buildings, meeting the development trend of "safety, environmental protection and energy saving". Colored facing mortar has the following advantages: (1) Environmentally friendly and non-toxic: The raw materials of colored facing mortar are mainly natural mineral materials, which do not contain volatile organic compounds such as free formaldehyde and benzene, are non-toxic and odorless, and are green and environmentally friendly. (2) Rich colors: The colors are simple and decorative, and can meet the decorative effects of different styles and different needs. (3) Excellent performance: It has good air permeability and hydrophobicity, and can form a colorful exterior wall decoration system with breathing function, which has significant moisture-proof and anti-seepage effects. It has excellent alkali resistance, pollution resistance and impact resistance, and a long service life of more than 20 years. It has good elasticity and low shrinkage, and is not easy to crack after painting.

[0044] The efflorescence of cement-based materials often has a serious impact on colored finishing mortars. Efflorescence usually forms white salt deposits on the surface of colored finishing mortars. These deposits are in sharp contrast with the original color of the mortar, thus destroying the overall decorative effect of the mortar. Especially when the color of the colored mortar is darker, the white spots formed on the surface will be more obvious, seriously affecting the aesthetics of the building, and even causing the mortar to crack, fall off and other problems during use. At present, the efflorescence treatment processes mainly include acid washing, sandblasting, etc., which will inevitably cause damage to the concrete surface. For this reason, internally added efflorescence inhibitors have appeared on the market. Most of these efflorescence inhibitors are organic components. While inhibiting efflorescence to a certain extent, they will also reduce the compressive strength of the finishing mortar.

[0045] In order to solve the above technical problems, the present invention provides a colored facing mortar, which comprises, by weight:

[0046] 20 to 30 parts by weight of cement;

[0047] 40-60 parts by weight of sand;

[0048] 0.2-1 parts by weight of latex powder;

[0049] 0.3-0.5 parts by weight of cellulose ether;

[0050] 0 to 3 parts by weight of a reinforcing agent;

[0051] 1-5 parts by weight of an inorganic pigment; and,

[0052] 0.5 to 3 parts by weight of efflorescence inhibitor.

[0053] In the technical solution of the present invention, cement provides strength and durability to the colored facing mortar after hardening; sand increases the volume of the mortar and helps to control the shrinkage and expansion of the colored facing mortar; cellulose ether can thicken the colored facing mortar and improve the water retention of the colored facing mortar; the efflorescence inhibitor can reduce the phenomenon of salt deposition on the surface caused by water evaporation (i.e., efflorescence) to maintain the beauty of the finish; the inorganic pigment has excellent color stability and weather resistance, and can maintain bright colors after long-term exposure to the natural environment; the enhancer promotes the colored facing mortar to form a tighter particle arrangement, improves the internal density, and thus improves the compressive strength.

[0054] It is understandable that the cement can be selected as silicate cement, with no limitation on color and grade. After hardening, silicate cement can provide higher compressive and tensile strengths, which helps to improve the compressive strength of the entire colored facing mortar.

[0055] It is understandable that the sand is natural river sand, machine-made sand, etc. The particles of natural river sand are round, less mud content, and uniform color, which is suitable for high requirements for surface finish; the particles of machine-made sand are angular, hard, and wear-resistant, and the resources are abundant and environmentally sustainable. The mesh number (particle size) of the sand needs to be adjusted according to the specific application to ensure the density, workability and compressive strength of the colored facing mortar, and the mesh number is not particularly limited here.

[0056] In one embodiment, the reinforcing agent includes cupric chloride dihydrate. In this way, the addition of cupric chloride dihydrate changes the hydration process of the cement, and the hydration product of the cement develops from needle-shaped to flake-shaped, which increases the density inside the cement, thereby increasing the compressive strength of the test block of the color facing mortar.

[0057] In one embodiment, the efflorescence inhibitor includes one or any combination of magnesium chloride, zinc chloride, aluminum chloride and polyaluminum chloride. In this way, the efflorescence inhibitor can react chemically with calcium hydroxide (Ca(OH)2) in the cement to generate insoluble compounds, thereby preventing soluble salts from migrating to the surface of the colored facing mortar to form efflorescence. At the same time, by changing the pH environment in the colored facing mortar system, the tendency of alkaline substances to migrate to the surface is suppressed. It can be understood that zinc chloride (ZnCl□): is a good retarder that can delay the initial hydration of cement and reduce the production of calcium hydroxide; magnesium chloride (MgCl□) and aluminum chloride (AlCl□): can react with the cement hydration product to form a stable complex, close the capillary pores, and help to improve the early strength of the colored facing mortar; polyaluminum chloride (PAC): as a highly efficient inorganic polymer coagulant, it has a very strong adsorption effect and has a good efflorescence inhibition effect.

[0058] In one embodiment, the inorganic pigment includes an iron-based inorganic pigment. In this way, the iron-based inorganic pigment has excellent color stability and weather resistance, good resistance to acid and alkali environments, can maintain bright colors after long-term exposure to natural environments, is not easy to fade or deteriorate, and will not react adversely with the cement hydration product. It is understood that the iron-based inorganic pigments are iron black, iron yellow, iron red, etc., and are not particularly limited here.

[0059] In one embodiment, the latex powder includes a copolymer of two or three of vinyl acetate, ethylene and acrylic acid. In this way, the vinyl acetate has good bonding and film-forming properties, can enhance the adhesion between the mortar and the substrate, improve the workability and water retention of the mortar, and help prevent cracking. The ethylene can increase flexibility and impact resistance, making the mortar more durable. The acrylic acid can improve weather resistance and UV resistance, and extend the service life of the material. By reasonably selecting a copolymer containing two or three monomers of the vinyl acetate, the ethylene and the acrylic acid as the latex powder, multiple optimizations of bonding, flexibility, weather resistance and workability can be achieved without affecting the core performance of the color facing mortar.

[0060] In one embodiment, the cellulose ether includes one or two of methyl cellulose ether, hydroxypropyl cellulose ether, hydroxypropyl starch ether and hydroxymethyl starch ether. In this way, the methyl cellulose ether has good thickening and water retention properties, can effectively prevent excessive water loss, and is beneficial to improving the bonding strength between the colored facing mortar and the base layer. The hydroxypropyl cellulose ether has excellent dispersibility and fluidity, reduces shrinkage cracks caused by water evaporation, and has good water retention capacity, making the mortar easier to apply and level. The hydroxypropyl starch ether has good thickening and stabilizing effects, which is beneficial to improving the overall density and weather resistance of the colored facing mortar. The hydroxymethyl starch ether helps to accelerate the hardening process of the colored facing mortar and shorten the construction period. By reasonably selecting one or two of the methyl cellulose ether, the hydroxypropyl cellulose ether, the hydroxypropyl starch ether and the hydroxymethyl starch ether as the cellulose ether, multiple optimizations of workability, water retention and stability can be achieved without affecting the core performance of the colored facing mortar.

[0061] The present invention also provides a method for preparing a colored facing mortar, wherein the components of the colored facing mortar are calculated by weight and include: 20 to 30 parts by weight of cement; 40 to 60 parts by weight of sand; 0.2 to 1 parts by weight of latex powder; 0.3 to 0.5 parts by weight of cellulose ether; 0 to 3 parts by weight of a reinforcing agent; 1 to 5 parts by weight of an inorganic pigment; and 0.5 to 3 parts by weight of an alkali-inhibitor;

[0062] The preparation method of the color facing mortar comprises the following steps: mixing and stirring the components of the color facing mortar for the first time to obtain dry powder color facing mortar; adding water to the dry powder color facing mortar and mixing and stirring for the second time to obtain the color decorative mortar. In this way, through the first mixing and stirring, the components can be evenly distributed to avoid local aggregation, which affects the performance of the final color facing mortar. Through the first mixing and stirring, the components can be evenly distributed to avoid local aggregation, which affects the performance of the final color facing mortar; through the second mixing and stirring, the components can be fully hydrated and evenly distributed, thereby improving the final quality, decorative effect and durability of the color facing mortar.

[0063] In one embodiment, the first mixing and stirring time is 10 to 15 minutes. In this way, it can ensure that each component is dispersed evenly during this time, while reducing damage to each component. For example, long-term mixing causes damage or degradation of some component chopped fibers, affecting the performance of the final colored finish.

[0064] In one embodiment, the second mixing and stirring time is 1.5 to 2.5 minutes. In this way, this time range not only ensures the mixing effect, but also avoids the negative effects caused by excessive stirring, and can ensure that each component is fully hydrated and evenly distributed without affecting the core performance of the color facing mortar, which is conducive to the preparation of high-quality color facing mortar.

[0065] In one embodiment, the step of adding water to the dry powder color finishing mortar for a second mixing and stirring specifically includes: adding the dry powder color finishing mortar to the water in a quantity by quantity for a second mixing and stirring. In this way, each time a portion of the dry powder color finishing mortar is added, a short stirring is immediately performed to ensure that each batch of the dry powder color finishing mortar can quickly contact with water and start a hydration reaction, which is conducive to reducing the possibility of the dry powder color finishing mortar forming lumps in water.

[0066] The technical solution of the present invention is further described in detail below in conjunction with specific embodiments and drawings. It should be understood that the following embodiments are only used to explain the present invention and are not used to limit the present invention.

[0067] Example 1

[0068] A method for preparing a colored facing mortar comprises the following steps:

[0069] 20 parts by weight of 32.5 ordinary Portland cement, 40 parts by weight of river sand, 0.2 parts by weight of ethylene propylene glycol copolymer, 0.3 parts by weight of hydroxypropyl cellulose ether, 5 parts by weight of iron black, 2 parts by weight of cupric chloride dihydrate and 1 part by weight of polyaluminium chloride are added into a stirrer and stirred for 10 minutes. After uniform mixing, a dry powder coloured facing mortar is obtained and set aside. A certain amount of the dry powder coloured facing mortar is weighed, water is poured into a mixing barrel, and the dry powder coloured facing mortar is slowly sprinkled into the mixture under low-speed stirring of a planetary cement mortar mixer, and stirred for 15 seconds. The stirring blade is removed, and the mortar on the stirring blade and the wall of the mixing barrel is cleaned within 60 seconds, and the stirring blade is reinserted, and stirred for 75 seconds to obtain the coloured facing mortar.

[0070] Example 2

[0071] A method for preparing a colored facing mortar comprises the following steps:

[0072] 30 parts by weight of 42.5 white cement, 60 parts by weight of standard sand, 1 part by weight of ethylene propylene acid copolymer, 0.5 parts by weight of hydroxypropyl cellulose ether, 1 part by weight of iron black, 0.5 parts by weight of cupric chloride dihydrate and 0.5 parts by weight of polyaluminium chloride are added into a stirrer and stirred for 10 minutes. After uniform mixing, a dry powder coloured facing mortar is obtained and set aside. A certain amount of the dry powder coloured facing mortar is weighed, water is poured into a mixing barrel, and the dry powder coloured facing mortar is slowly sprinkled into the mixture under low-speed stirring of a planetary cement mortar mixer, and stirred for 15 seconds. The stirring blade is removed, and the mortar on the stirring blade and the wall of the mixing barrel is cleaned within 60 seconds, and the stirring blade is reinserted, and stirred for 75 seconds to obtain the coloured facing mortar.

[0073] Example 3

[0074] A method for preparing a colored facing mortar comprises the following steps:

[0075] 20 parts by weight of 32.5 ordinary Portland cement, 40 parts by weight of river sand, 0.2 parts by weight of ethylene propylene acid copolymer, 0.3 parts by weight of hydroxypropyl cellulose ether, 5 parts by weight of iron black, 1 part by weight of cupric chloride dihydrate and 2 parts by weight of magnesium chloride are added into a stirrer and stirred for 10 minutes. After uniform mixing, a dry powder color facing mortar is obtained and set aside. A certain amount of dry powder color facing mortar is weighed, water is poured into a mixing barrel, and the dry powder color facing mortar is slowly sprinkled in with a planetary cement mortar mixer at a low speed, stirred for 15 seconds, a stirring blade is taken out, the mortar on the stirring blade and the wall of the mixing barrel is cleaned within 60 seconds, the stirring blade is reinserted, and stirred for 75 seconds to obtain the colored facing mortar.

[0076] Example 4

[0077] A method for preparing a colored facing mortar comprises the following steps:

[0078] 20 parts by weight of 32.5 ordinary Portland cement, 40 parts by weight of river sand, 0.2 parts by weight of ethylene propylene acid copolymer, 0.3 parts by weight of hydroxypropyl cellulose ether, 5 parts by weight of iron black, 1 part by weight of cupric chloride dihydrate and 2 parts by weight of aluminum chloride are added into a stirrer and stirred for 10 minutes. After uniform mixing, a dry powder color facing mortar is obtained and set aside. A certain amount of dry powder color facing mortar is weighed, water is poured into a mixing barrel, and the dry powder color facing mortar is slowly sprinkled in with a planetary cement mortar mixer at a low speed, stirred for 15 seconds, a stirring blade is taken out, the mortar on the stirring blade and the wall of the mixing barrel is cleaned within 60 seconds, the stirring blade is reinserted, and stirred for 75 seconds to obtain the colored facing mortar.

[0079] Example 5

[0080] A method for preparing a colored facing mortar comprises the following steps:

[0081] 20 parts by weight of 32.5 ordinary Portland cement, 40 parts by weight of river sand, 0.2 parts by weight of ethylene propylene glycol copolymer, 0.3 parts by weight of hydroxypropyl cellulose ether, 5 parts by weight of iron black, 3 parts by weight of cupric chloride dihydrate and 3 parts by weight of polyaluminium chloride are added into a stirrer and stirred for 10 minutes. After uniform mixing, a dry powder coloured facing mortar is obtained and set aside. A certain amount of the dry powder coloured facing mortar is weighed, water is poured into a mixing barrel, and the dry powder coloured facing mortar is slowly sprinkled into the mixture under low-speed stirring of a planetary cement mortar mixer, and stirred for 15 seconds. The stirring blade is removed, and the mortar on the stirring blade and the wall of the mixing barrel is cleaned within 60 seconds, and the stirring blade is reinserted, and stirred for 75 seconds to obtain the coloured facing mortar.

[0082] Comparative Example 1

[0083] A method for preparing a colored facing mortar comprises the following steps:

[0084] 20 parts by weight of 32.5 ordinary Portland cement, 40 parts by weight of river sand, 0.2 parts by weight of ethylene propylene acid copolymer, 0.3 parts by weight of hydroxypropyl cellulose ether, 5 parts by weight of iron black and 2 parts by weight of aluminum chloride are added into a stirrer and stirred for 10 minutes. After uniform mixing, a dry powder color facing mortar is obtained and set aside. A certain amount of dry powder color facing mortar is weighed, water is poured into a mixing barrel, and the dry powder color facing mortar is slowly sprinkled in with a planetary cement mortar mixer at a low speed, stirred for 15 seconds, a stirring blade is taken out, the mortar on the stirring blade and the wall of the mixing barrel is cleaned within 60 seconds, the stirring blade is reinserted, and stirred for 75 seconds to obtain the colored facing mortar.

[0085] Comparative Example 2

[0086] A method for preparing a colored facing mortar comprises the following steps:

[0087] 20 parts by weight of 32.5 ordinary Portland cement, 40 parts by weight of river sand, 0.2 parts by weight of ethylene propylene acid copolymer, 0.3 parts by weight of hydroxypropyl cellulose ether, 5 parts by weight of iron black and 2 parts by weight of magnesium chloride are added into a stirrer and stirred for 10 minutes. After uniform mixing, a dry powder color facing mortar is obtained and set aside. A certain amount of dry powder color facing mortar is weighed, water is poured into a mixing barrel, and the dry powder color facing mortar is slowly sprinkled in with a planetary cement mortar mixer at a low speed, stirred for 15 seconds, a stirring blade is taken out, the mortar on the stirring blade and the wall of the mixing barrel is cleaned within 60 seconds, the stirring blade is reinserted, and stirred for 75 seconds to obtain the colored facing mortar.

[0088] Comparative Example 3

[0089] A method for preparing a colored facing mortar comprises the following steps:

[0090] 20 parts by weight of 32.5 ordinary Portland cement, 40 parts by weight of river sand, 0.2 parts by weight of ethylene propylene glycol copolymer, 0.3 parts by weight of hydroxypropyl cellulose ether, 5 parts by weight of iron black and 2 parts by weight of polyaluminium chloride are added into a stirrer and stirred for 10 minutes. After uniform mixing, a dry powder coloured facing mortar is obtained and set aside. A certain amount of the dry powder coloured facing mortar is weighed, water is poured into a mixing barrel, and the dry powder coloured facing mortar is slowly sprinkled into the mixture under low-speed stirring of a planetary cement mortar mixer, and stirred for 15 seconds. The stirring blade is removed, and the mortar on the stirring blade and the wall of the mixing barrel is cleaned within 60 seconds, and the stirring blade is reinserted, and stirred for 75 seconds to obtain the coloured facing mortar.

[0091] Comparative Example 4

[0092] A method for preparing a colored facing mortar comprises the following steps:

[0093] 20 parts by weight of 32.5 ordinary Portland cement, 40 parts by weight of river sand, 0.2 parts by weight of ethylene propylene acid copolymer, 0.3 parts by weight of hydroxypropyl cellulose ether, 5 parts by weight of iron black and 2 parts by weight of zinc chloride are added into a stirrer and stirred for 10 minutes. After uniform mixing, a dry powder color facing mortar is obtained and set aside. A certain amount of dry powder color facing mortar is weighed, water is poured into a mixing barrel, and the dry powder color facing mortar is slowly sprinkled in with a planetary cement mortar mixer at a low speed, stirred for 15 seconds, a stirring blade is taken out, the mortar on the stirring blade and the wall of the mixing barrel is cleaned within 60 seconds, the stirring blade is reinserted, and stirred for 75 seconds to obtain the colored facing mortar.

[0094] Comparative Example 5

[0095] A method for preparing a colored facing mortar comprises the following steps:

[0096] 20 parts by weight of 32.5 ordinary Portland cement, 40 parts by weight of river sand, 0.2 parts by weight of ethylene propylene glycol copolymer, 0.3 parts by weight of hydroxypropyl cellulose ether and 5 parts by weight of iron black are added into a stirrer and stirred for 10 minutes. After uniform mixing, a dry powder color facing mortar is obtained and set aside. A certain amount of dry powder color facing mortar is weighed, water is poured into a mixing barrel, and the dry powder color facing mortar is slowly sprinkled in with a planetary cement mortar mixer at a low speed, stirred for 15 seconds, a stirring blade is taken out, the mortar on the stirring blade and the wall of the mixing barrel is cleaned within 60 seconds, the stirring blade is reinserted, and stirred for 75 seconds to obtain the color facing mortar.

[0097] Experimental test 1, by photographing the samples of the above-mentioned embodiments 1-5 and comparative examples 1-5 under the same lighting conditions, the optical density value of the colored finishing mortar was analyzed using ImagePro plus software.

[0098] The test results are shown in Table 1 below:

[0099] Table 1 shows the optical density values ​​of the samples of Examples 1-5 and Comparative Examples 1-5

[0100]

[0101]

[0102] Among them, the sample pictures of Example 1 and Example 3, and Comparative Example 5 are as follows Figures 1 to 3 shown.

[0103] From the above, we can see that the larger the optical density value, the darker the color of the sample. The efflorescence inhibitor can inhibit the color fading of the colored finishing mortar and maintain the beauty of the finishing.

[0104] Experimental test 2, by using the samples of the above-mentioned embodiments 1-5 and comparative examples 1-5 to test the 7d (7 days) compressive strength according to the "Basic Performance Test Method of Building Mortar" JGJ70 in the field of Chinese construction engineering.

[0105] The test results are shown in Table 2 below:

[0106] Table 2 shows the 7d (7 days) compressive strength of the samples of Examples 1-5 and Comparative Examples 1-5.

[0107] sample 7d compressive strength / MPa Example 1 28.6 Example 2 38.1 Example 3 29.5 Example 4 30.4 Example 5 42.5 Comparative Example 1 28.9 Comparative Example 2 25.7 Comparative Example 3 5.2 Comparative Example 4 7.1 Comparative Example 5 26.5

[0108] Among them, the electron microscope image of the sample of Example 5 is shown in Figure 4, and the electron microscope image of the sample of Comparative Example 5 is shown in Figure 5.

[0109] It can be seen from the above that the reinforcing agent promotes the formation of a tighter particle arrangement of the colored facing mortar, improves the internal density, and thus improves the compressive strength.

[0110] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A colored facing mortar, characterized in that: By weight, including: 20-30 parts by weight of cement; 40-60 parts by weight of sand; 0.2-1 parts by weight of latex powder; 0.3-0.5 parts by weight of cellulose ether; 0 to 3 parts by weight of a reinforcing agent; 1-5 parts by weight of an inorganic pigment; and, 0.5 to 3 parts by weight of efflorescence inhibitor.

2. The colored facing mortar according to claim 1, characterized in that: The enhancer includes cupric chloride dihydrate.

3. The colored facing mortar according to claim 1, characterized in that: The efflorescence inhibitor includes one or any combination of magnesium chloride, zinc chloride, aluminum chloride and polyaluminum chloride.

4. The colored facing mortar according to claim 1, characterized in that: The inorganic pigment includes an iron-based inorganic pigment.

5. The colored facing mortar according to claim 1, characterized in that: The latex powder includes a copolymer of two or three of vinyl acetate, ethylene and acrylic acid.

6. The colored facing mortar according to claim 1, characterized in that: The cellulose ether includes one or two of methyl cellulose ether, hydroxypropyl cellulose ether, hydroxypropyl starch ether and hydroxymethyl starch ether.

7. A method for preparing a colored facing mortar, characterized in that: The preparation of the colored facing mortar according to any one of claims 1 to 6 comprises the following steps: Mixing and stirring the various components of the color finishing mortar for the first time to obtain a dry powder color finishing mortar; The dry powder colored finishing mortar is added with water and mixed and stirred for a second time to obtain the colored decorative mortar.

8. The method for preparing the colored facing mortar according to claim 7, characterized in that: The first mixing and stirring time is 10 to 15 minutes; and / or, The second mixing and stirring time is 1.5 to 2.5 minutes; and / or, The step of adding water to the dry powder color finishing mortar for a second mixing and stirring specifically includes: adding the dry powder color finishing mortar into water in small amounts for a second mixing and stirring.

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