CN112159229B

CN112159229B - Antibacterial reinforced bone china

Info

Publication number: CN112159229B
Application number: CN202011096980.1A
Authority: CN
Inventors: 高秋祥; 高峰; 师全
Original assignee: Pingding Yingyu Porcelain Co ltd
Current assignee: Pingding Yingyu Porcelain Co ltd
Priority date: 2020-10-14
Filing date: 2020-10-14
Publication date: 2022-09-27
Anticipated expiration: 2040-10-14
Also published as: CN112159229A

Abstract

The invention relates to ceramic production, in particular to antibacterial reinforced bone china; the bone-setting brick is made of blank and glaze, 40-43 parts of bone carbon, 22-25 parts of wulan tea crystal stone, 18-33 parts of Pingding three-flower gangue and 12-18 parts of Pingding dry surface; the glaze comprises 95 parts of frit, 3 parts of flat dry surface and 2 parts of cellulose in parts by weight; the formula design is carried out by adopting the wulan tea crystal stone as the main raw material of the ceramic blank and glaze, no special additive is required to be added, the cost of the domestic or imported antibacterial agent in the current market is basically 40-120 ten thousand per ton, the cost is extremely high, the cost of the ceramic ingredients is basically not greatly improved by the wulan tea crystal stone, and the test result shows that the antibacterial effect is excellent; high strength, strong thermal shock resistance, and the shock strength is improved by more than one time compared with the traditional ceramics, and reaches the center 1.875J/cm ² Edge 1.17J/cm ² 。

Description

Antibacterial reinforced bone china

Technical Field

The invention relates to ceramic production, in particular to antibacterial reinforced bone china.

Background

In recent years, as consumers have been increasingly aware of daily ceramic products, higher demands have been made on the aesthetic and functional properties of the daily ceramic products. The concrete main points are as follows: 1. the lead and cadmium elution amount not only reaches the national standard, but also reaches the FDA international standard. 2. The beauty and the richness of colors are required to be pursued for practicality, and the requirements for updating products are also required. 3. The popularity of the big health concept, consumers are more concerned about health functions. This presents a new topic for our ceramic industry. This item is implemented for this purpose.

Staphylococcus aureus is an important pathogenic bacterium in humans, belonging to the genus Staphylococcus, which is also known as a mesophilic bacterium, and is a representative of gram-positive bacteria, and causes many serious infections. The two kinds of bacteria have a lot of pollution opportunities in food, and the American center for disease control reports that the infections caused by escherichia coli and staphylococcus aureus to human bodies account for the first and second places respectively. The epidemiology of the disease is characterized in that various toxic foods are available, and milk, meat and fish and products thereof are common in spring and summer. In recent years, researchers have conducted many exploratory researches, at present, two methods are mainly used for killing surface bacterial microorganisms, one is a surface antibacterial layer technology, a layer of antibacterial material is further coated on the surface of a ceramic glaze layer, the antibacterial layer is fixed through a low-temperature sintering method, antibacterial ingredients are directly involved in a ceramic glaze melting process through the antibacterial agent added to the glaze material technology, the first method is that the antibacterial materials are two, one is a photocatalytic titanium oxide material, and the surface microorganisms are killed through the redox reaction of trivalent titanium ions and tetravalent titanium ions under the action of light. The earliest antibacterial technology of the Japan Dongtao company is to apply a transparent titanium oxide photocatalytic antibacterial layer on a glaze layer. The other method is to thermally spray metal silver paste on the surface of the ceramic glaze layer, take the metal silver as an anode and form a very thin silver film on the surface of the glaze layer by adopting a plasma spraying method, thereby achieving the sterilization effect of the surface. This technology is still used by antibacterial sanitary wares of the company of empferia japan at present. The second method is to add antibacterial agent directly into glaze to prepare antibacterial functional glaze, and this technology was originally developed and invented by Egyptian corporation of Japan. At present, the existing domestic antibacterial ceramics mainly adopt the technology, and at present, more antibacterial agent manufacturers exist, wherein the antibacterial agent produced by American Miaokang corporation is the best. There are many domestic products, such as Xiamen jin science and technology, Shandong Boner science and technology, and Fushan Li Yuan chemical industry. The method has the problems of high metal component mixing amount, high cost, limited adding amount (generally 1-2 parts), loss of high-temperature sintering components and easy fluctuation of antibacterial performance.

The applicant finds that the wulan tea crystal stone serving as a fluxed ceramic raw material can obviously improve the strength and the thermal shock resistance of a ceramic material after being fired, and can be used for producing reinforced porcelain, heat-resistant porcelain and the like; the ceramic product produced based on the Wulan tea spar has the functions of far infrared, antibiosis and easy cleaning.

Disclosure of Invention

The invention aims to provide an antibacterial reinforced bone china, wherein a novel wulan tea crystalline stone material is added into a material formula, and a unique process technology is utilized, so that the product has an antibacterial function and the strength and toughness of the product are enhanced. The antibacterial performance of the antibacterial ceramic product is detected by a national fixed-point detection mechanism, and the two indexes of staphylococcus aureus and escherichia coli reach and are superior to the national standard JC/T897-2014 antibacterial ceramic product antibacterial performance.

In order to solve the technical problems, the technical scheme adopted by the invention is as follows:

the antibacterial reinforced bone china is prepared from a blank and a glaze, wherein the blank comprises the following components in parts by weight: 40-43 parts of bone charcoal, 22-25 parts of oolong tea crystal stone, 18-33 parts of Pingding three-flower gangue and 12-18 parts of Pingding dry surface; the glaze comprises, by weight, 95 parts of frit, 3 parts of flat dry surface and 2 parts of cellulose.

The composition of the above-mentioned blank and glaze each has a well-known chemical composition (in parts) as shown in the following table:

analysis of rare earth element in Wulan tea spar trace (unit: mg/kg)

Element(s)	La ₂ O ₃	CeO ₂	Pr ₈ O ₁₁	Nd ₂ O ₃	Sm ₂ O ₃	Eu ₂ O ₃	Gd ₂ O ₃	Tb ₄ O ₇
									Results	61.46	129.47	12.97	40.87	6.71	0.66	7	0.89
Element(s)	Dy ₂ O ₃	Ho ₂ O ₃	Er ₂ O ₃	Tm ₂ O ₃	Yb ₂ O ₃	Lu ₂ O ₃	Y ₂ O ₃
									Results	4.68	0.83	2.47	0.33	2.12	0.62	24.60

The invention also provides a preparation method of the antibacterial reinforced bone china, which comprises the following steps:

step one, proportioning blanks in parts by weight, ball-milling the blanks, sieving for removing iron, filtering mud, performing vacuum mud refining and ageing of mud, performing second vacuum mud refining and ageing of mud, shaping blanks after blank making and shaping, performing biscuit firing after the biscuit making, and polishing to obtain a smooth and fine biscuit firing product without impurities;

step two, proportioning glaze materials in parts by weight, performing wet ball milling on the glaze materials, preparing glaze slip, and deironing and sieving the glaze slip to obtain standby glaze slip;

and step three, spraying glaze on the biscuit firing product obtained in the step one by using the standby glaze slip prepared in the step two, and firing after glaze spraying to obtain the antibacterial reinforced bone china.

Further, when the blank is ball-milled, the blank is uniformly mixed according to the formula proportion, and the mixture enters a ball mill according to the following materials: ball stones: 1 part of water: 1.8: 1, and performing wet grinding and fine crushing, and performing fineness test analysis, wherein the standard is 0.09-0.15 part of residue of a ten-thousand-hole sieve of the slurry.

Further, when glaze slurry is subjected to ball milling, the glaze material in the formula is filled into a wet ball mill for fine crushing, and the raw materials are as follows: ball stones: water 1: 1.8: the 0.4 grind fineness criteria were: 0.01 to 0.02 portion of residue of a ten-thousand-hole sieve.

Preferably, the first ageing process of the pug in the first step is to store the pug strips subjected to vacuum pugging in a clean pug storehouse with the ambient temperature of 15-25 ℃ and the relative humidity of 50 parts HR for ageing, wherein the ageing period is about 3-7 days, the environment must be clean and tidy, the pug strips cannot fall to the ground and can not be stained, and the pug strips can not be mixed with impurities.

Preferably, biscuiting is finished in a natural gas tunnel kiln, a gas tunnel kiln or an electric-burning shuttle kiln, wherein the burning temperature is 1230-1250 ℃, and the burning curve is as follows: room temperature-200 deg.C, 60 min; at 200-400 deg.c for 90 min; 400-600 ℃ for 100 minutes; 600-900 ℃ for 120 minutes; 900-1000 ℃ for 40 minutes; 90 minutes at 1000-1200 ℃; 1200-1250 ℃ for 40 minutes; keeping the temperature for 2 hours, and cooling to 700 ℃ for two hours.

Preferably, the method is characterized in that the firing after the glaze spraying in the three steps is finished in a natural gas tunnel kiln, a gas tunnel kiln or an electric-firing shuttle kiln, and qualified products are obtained at the firing temperature of 1130-1150 ℃; the firing curve is as follows: room temperature-200 deg.C, 60 min; at 200-400 deg.c for 90 min; 400-600 ℃ for 100 minutes; 600-900 ℃ for 120 minutes; 900-1000 ℃ for 60 minutes; 1000-1150 ℃ for 90 minutes; keeping the temperature for 1 hour, and cooling to 700 ℃ for two hours.

Assessment and performance research of the oolong tea spar raw materials:

(1) strength test (including mechanical strength and thermal shock resistance)

1) Mechanical strength

A basic formulation was designed based on the wulan theophyllite mineral composition and chemical composition, as shown in table 1.

TABLE 1 basic ceramic formulation (wt%)

The formula is prepared into pug for standby according to a normal ceramic process, and the pug of the formula is called G material. For G material, the sintering point and expansion coefficient of the material are measured, the ceramic material which is sintered at the sintering point of 1250-.

On the basis of the G material, the Wulan tea spar is ground to 250 meshes, the powder is marked as W, and the powder is matched and mixed with the G material, and the marked as Bx material is shown in Table 2.

TABLE 2 proportioning of the materials B (wt/wt)

Along with the increase of the proportion of the wulan theophyllite, the sintering temperature of the material is reduced, and the sintering point of each sample is measured. By B9, the sintering point reached 1185-1200 ℃.

The above B1-B9 were used to prepare test pieces of 3mm in thickness, and the above impact strength test was repeated, and the results are shown in Table 3.

TABLE 3 impact resistance test results (J)

The experimental result of the relationship between the adding amount of the wulan tea stones and the strength can obtain that the wulan tea stones reach the highest strength section in the same system basic component within the range of 25% -50%, and the performance reaches the highest value when the adding amount of the wulan tea stones is 25% -40% according to the drawn trend line. The rapid increase in strength starting from 20% content is concluded to be a slightly different result for the G base stock if the base composition is changed, since these ceramic products are substantially in the porcelain forming range of the K2O-Al2O3-SiO2 phase diagram (except for magnesium porcelain). Besides, the sintering temperature of the blank and the thermal expansion coefficient of the material at each temperature stage are comprehensively considered, and the forming performance, the green body strength and other factors in the process are also considered. Due to the different forming modes and different sintering processes (slow sintering and fast sintering) in various ceramic products, the adding amount of the wulan tea spar in the practical application can be greatly different according to specific products, but the excellent performances of the wulan tea spar are not very strong when the adding amount is less than 20%.

2) Thermal shock resistance

The thermal shock resistance of a ceramic material depends on two factors, one is the strength of the ceramic material itself, which is the amount of expansion with heat and contraction with cold (i.e., the rate of thermal expansion). The former is the intrinsic property of the material itself, and the latter is the change caused by the change of external conditions. We prepared 5mm by 50mm bars at respective sintering temperatures for 20%, 30%, 35%, 40% bird's web and tested the respective coefficients of thermal expansion, as shown in table 4.

TABLE 4 expansion coefficient test results (10) ^-6 ℃)

The thermal expansion coefficient test shows that the overall thermal expansion coefficient of the material is lower than that of the traditional ceramic body material, and the thermal expansion coefficient is slightly reduced along with the increase of the proportion of wulan tea stones, which is caused by a large amount of plagioclase and microcline in wulan tea stones, and is consistent with the results of the previous research (see the silicate handbook), but the overall change range is not large, namely, the overall thermal expansion coefficient of the material does not change rapidly in the process of increasing the adding amount of wulan tea stones, which is mainly caused by the fact that a large amount of amorphous quartz exists in the mineral composition of wulan tea stones, and semi-stable cristobalite is formed in the heating process, and the existence of the semi-stable cristobalite can increase the thermal expansion value of the material and is just opposite to the large amount of microcline and plagioclase. Macroscopically this is shown by the fact that the thermal expansion properties of the material do not fluctuate much. The result brings about two influences, if an unglazed product is produced, the thermal shock resistance of the material is excellent, the material can reach 280-20 ℃ without burst when tested according to the method specified by the national standard GB/T3532-2009, but in practical application, the application examples of the unglazed product are few, most of the unglazed product needs to be glazed, and only the all-ceramic tile polishing product does not need to be glazed. Once glazing, because the expansion coefficient of the glaze in the current use is larger than that of the blank, no matter the raw glaze, the fritted glaze or the semi-fritted glaze has the phenomenon that the expansion coefficient of the glaze is larger than that of the blank, a tensile stress glaze layer of the glaze is cracked in the production and use processes, the one-time firing cannot be strong due to the transitional buffer action of the blank glaze in the blank glaze, but the firing product has problems. Therefore, when the wulan theophyllite is used as the main flux raw material in the blank, the material formula must be thoroughly improved. Because a large amount of feldspar or feldspar materials are applied to the original blank in China, in order to reasonably introduce wulan tea spar as the main flux type raw material of the blank body, the formula transformation can be carried out without using different types of materials, the result is tested on various types of ceramics in the application research of the project, and a better effect is obtained. So far, we can certainly say that the standardized Wulan theophyllite raw materials can be applied to more detailed technical work in daily-use construction purchase and sanitation, and professional enterprises need to further research according to own processes and production lines to achieve stable production and improve quality.

(2) Functional experiments and tests

1) Research and test of far infrared function

First we tested the far infrared function of the wulan thea crystal stone raw ore, see table 5.

TABLE 5 ultra-far infrared test of wulan tea-crystal stone raw ore

From the above far infrared test results of the wulan tea spar raw material, we can see that wulan tea spar and raw ore can emit far infrared rays with the wavelength of 220m and the relative energy of more than 0.7 at normal temperature, wherein the highest intensity can reach 0.87 at the wave band of 3-5m, and can reach about 0.8 at 5-20 μm, and the processed and purified wulan tea spar is not much different from the raw ore, the wave band performance is approximately the same, and the relative energy value is slightly reduced.

In the ceramic proportion, according to the previous chapter experiment results, the proportion of the glaucophyllite added is basically between 20 and 50 percent (aiming at daily ceramics, architectural ceramics and sanitary wares, not including the later-stage physical therapy porcelain products), and then when the addition is below 50 percent, whether the far infrared function is lower than that of the raw material (or raw ore)? In practice, the formula consisting of different types in various proportions is tested, and the basic conclusion is as follows: the far infrared emission intensity is increased along with the increase of the adding amount of the Wulan tea-spar; the components in the B composition are different, and the far infrared emission intensity of the material is obviously different. But the overall band is narrowed. The relative values of far infrared emission for different proportions of wulan theophyllite are listed in table 6.

TABLE 6 relative energy of far infrared emission of wulan tea spar in different ceramic materials (wavelength maximum between 2-22 μm)

Therefore, the conclusion can be drawn that the ceramic product made from the wulan tea spar is a ceramic product with the function of emitting infrared rays, the wavelength of the ceramic product is within the range of 2-20 microns, the far infrared emission intensity is increased along with the increase of the adding amount of wulan tea spar, and simultaneously, the phase composition of the wulan tea spar formed in ceramics made of different materials is different due to the difference of reactant formulas. The different phases show the difference of internal energy (enthalpy) of the ceramic material, and also show that a plurality of rare earth elements contained in the wulan tea crystalloid enter into the crystal phase of the material to generate anomorphic body of the anomorphic body, and a part of rare earth oxides or (certain mineral) in the crystal boundary hinders the migration of liquid phase components to the crystal phase so as to inhibit the growth and growth of the crystal, thereby leading to the increase of the internal energy of the phase, and further increasing the vibration energy, the movement kinetic energy, the rotation kinetic energy and the like of the irregular movement of ions in the material, and a part of the rare earth oxides are melted in the glass phase to play a toughening role. Based on this analysis, we judged that ceramic materials incorporating wulan tea crystals can exhibit strong blackbody properties at high temperatures. In practice, when the daily-used ceramic is prepared by secondary sintering, the same frit glaze is used in the secondary glaze sintering process, and when the daily-used ceramic is subjected to glaze sintering in the same kiln, the plain body glaze surface without the glauconite is good in quality, and the ceramic plain body glaze surface containing the glauconite is over-sintered to show orange glaze and even bubbles. The firing temperature of the same product is reduced, the glaze firing temperature is reduced from 1140 ℃ to 1130 ℃, 1120 ℃, 1110 ℃, 1090 ℃ and 1080 ℃ through multiple times of trial firing, and compared with the glaze firing effect, the glaze firing quality within the range of 1090 plus 1110 ℃ is optimal and is reduced by 30-50 ℃ compared with the glaze firing temperature of the original product. In the same one-time fired daily porcelain, the same raw glaze is used, and the blank of the wulan tea spar is added to be fired to obtain a glaze surface which is generally better than that of the original product, is flat, bright and fine, and has obviously reduced glaze surface defects (see application test parts and object samples). This shows that in the high temperature stage, the temperature of the product is higher than the temperature of the kiln due to the fact that the green body shows strong black body property, so that the whole melting process of the glaze is prolonged, and the temperature is increased. In addition, the porcelain forming speed of all the daily porcelain varieties is greatly increased, the pushing speed is 22 cars/shift originally, the highest pushing speed is increased to 27 cars/shift, and the water absorption rate of the product is very low. The analysis reason is that a plurality of rare earth trace elements contained in the A. play a good role in mineralization and accelerate the reaction speed of porcelain formation. B. The black body properties exhibited by the green body result in a reduction in firing time.

2) Research and test of antibacterial function

The results of the antibacterial tests of various developed products are shown in Table 7.

TABLE 7 antibacterial Rate% of different ceramic materials (see test report)

According to different proportions of the wulan tea spar contained in a plurality of porcelain varieties, different effects also appear in the presented antibacterial rate. The basic rule is that along with the improvement of the proportion of the wulan tea stones, the antibacterial rate is also continuously improved. For staphylococcus aureus and escherichia coli, it is believed that the enamel layer plays a dominant role and the body plays an auxiliary role for the former. In the latter case, the body plays a dominant role and the glaze layer plays an auxiliary role. Therefore, in order to increase the sterilization rate of staphylococcus aureus, the proportion of wulan theophyllite in the glaze layer needs to be increased, and in order to increase the sterilization rate of escherichia coli, the content of wulan theophyllite in the blank needs to be increased. Of course, different materials show different sterilization rates under the condition of the same proportion of the bird-lan tea spar. Generally, the higher the energy of the formed porcelain (high energy state structure), the higher the sterilization rate. When the water absorption of the green body is high, the contribution of the green body to the sterilization rate is rapidly reduced once the sample green body absorbs water. This is because electrons escaping from the green body are trapped by water and impair the ability of the surface to form radicals. It should be emphasized that the antibacterial property of the material is reduced when the surface of the material is coated with some organic silicon or non-polar substances because the material structure of the surface weakens the formation of free radicals and the strength is different, the sterilization rate is increased along with the increase of the proportion of wulan tea stones, and the sterilization rate is rapidly reduced when the proportion of wulan tea stones exceeds a certain value in the aspect of the strength. The antibacterial performance is related to the proportion of wulan tea stones and different system basic components, and is similar to the far infrared function in the aspect of antibacterial performance of the material, namely wulan tea stone is a main factor for exciting the antibacterial performance in a formula, but the expression result is different due to different excited substances, and the infrared emission function is basically the same as the infrared emission result.

Study on easy cleaning

The research finds that whether the product is subjected to secondary firing or primary firing, whether the glaze contains the wulan tea stone component or not, the washing experiment of the product shows easy cleaning performance, in this respect, because no standard can be relied on, no test data is available, only experience in use is provided, and the analysis reason is that as long as the blank contains the sufficient amount of the wulan tea stone component, after firing, because the porcelain body material can emit stronger far infrared rays and has negative ions on the surface, under the action of the energy, when water contacts the glaze surface, water molecules can show depolymerization phenomenon, namely the original aggregation state of the water molecules is changed into a dispersion state), the large molecular groups of the water can be changed into small molecular groups, the surface tension of the water can be reduced, the affinity of the water to the surface of the porcelain can be increased (the wettability is increased, the contact wetting angle is reduced), and therefore, the water can be preferentially attached to the glaze surface to form a water film, macroscopically it appears that the glaze of the porcelain is easier to clean.

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

the formula design is carried out by adopting the wulan tea stone as the main raw material of the ceramic blank and the glaze, no special additive is required to be added, the cost of the domestic or imported antibacterial agent in the current market is basically 40-120 ten thousand per ton, the cost is extremely high, the cost of the ceramic ingredients is basically not greatly increased by the wulan tea stone, and the test result shows that the antibacterial effect is excellent. When the addition amount of the wulan theophyllite is between 20 and 30 percent, the antibacterial rate exceeds more than 90 percent specified by the national standard, so that the ceramic product can be said to come out of a brand-new way of the antibacterial functional porcelain.

In addition, the Wulan tea spar is used as a fluxed ceramic raw material, the strength and the thermal shock resistance of the ceramic material can be obviously improved after the sintered material is sintered, the antibacterial reinforced bone china has high strength and strong thermal shock resistance, and the impact strength is improved by more than one time compared with the traditional ceramics, and reaches the central 1.875J/cm ² Edge 1.17J/cm ² (ii) a The breaking strength is improved by 10 percent and reaches 60.75 MPa. The antibacterial reinforced bone china also has the functions of far infrared, antibiosis and easy cleaning.

Detailed Description

The present invention is further illustrated by the following specific examples.

Example 1

1. Preparation of the pug

(1) Ingredients (taking the following weight proportion)

40 parts of bone charcoal, 25 parts of black blue tea crystal stone, 32 parts of Pingding trilobate gangue and 18 parts of Pingding dry surface;

the raw materials are uniformly mixed according to the proportion of the formula, and are put into a ball mill (according to the proportion of materials, ball stones and water, the ratio is 1: 1.8: 1) for wet grinding and fine crushing, and the fineness test analysis is carried out, wherein the standard is 0.09-0.15 part of screen residue of a ten-thousand-hole screen of slurry.

(2) Iron removal sieving

The slurry passes through 4 sets of iron removal screening systems, each set of system comprises two wet magnetic separators, and one three-layer vibrating screen (180 meshes, 200 meshes and 250 meshes respectively) obtains purified, uniform and qualified slurry with certain particle size distribution, and the slurry is put into a slurry pool for later use.

(3) Filter-pressing mud

The mechanical equipment used in the process is a plunger pump and a mud filter, the plunger pump is used for pumping the uniform qualified mud which is reserved in a mud pool into the mud filter, and the mud slices with water content of 20-25 parts are formed through the dehydration of filter cloth.

(4) Vacuum pugging and staleness of mud

A. And (3) carrying out vacuum pugging on the dewatered mud slices once by using a vacuum pug mill with the vacuum degree of not less than 0.09 MPa.

B. And (3) neatly storing the mud strips subjected to vacuum pugging in a clean mud warehouse with the ambient temperature of 15-25 ℃ and the relative humidity of 50 parts HR for ageing for about 3-7 days. The environment must be clean and tidy, and the mud strip can not fall to the ground, can not glue dirty, guarantees that the mud strip can not mix into impurity.

(5) Secondary vacuum pugging

A. And performing secondary vacuum pugging on the mud strips aged for 3-7 days, wherein the vacuum is controlled to be-0.09 MPa to-0.095 MPa, so that the water content of the mud strips is kept consistent and uniformly diffused in the process, and hard mud blocks and dry mud residues cannot appear. The prepared mud strip is aged for more than 24 hours, so that the moisture in the mud strip is fully and uniformly diffused for forming.

B. When the mud strip is used for forming, the vacuum pugging is carried out again, the vacuum degree is not lower than 0.092PMa in the process, and the purpose is to divide the mud strip into mud strips with various diameters and thicknesses which meet the requirements of various varieties.

2. Blank making

(1) The process adopts the forming equipment such as a rolling forming machine, a cold-pressing forming machine, pressure grouting, high-pressure grouting and the like to produce ceramic mud blanks with various shapes. In the process, the product is designed reasonably, the sizes of all parts are accurate, the gravity analysis is fully considered, the bottom weight and the mouth weight are light, the process is a key point, and the deformation defect can be caused in the firing process due to slight error in design.

(2) Drying the various products after forming to automatic demoulding, drying the demoulded products in a drying room with the ambient temperature of about 60 ℃, and controlling the water content to be below 2 parts to obtain qualified blanks.

(3) Repairing and testing blank

The working procedure adopts a trimmer, sand paper, iron sand and a sea brocade grading tool to polish the edge of the blank smoothly and polish the front and back of the product smoothly. The blank is carefully inspected by clear water to achieve round product mouth, smooth whole body, no defects of rolling marks, mud dragging, mud residue, blank missing and pimples exist, so that the product is attractive and elegant, and then the product is dried in a blank warehouse at the ambient temperature of about 30 ℃ to obtain qualified green blanks.

3. Biscuit firing

The working procedure can be completed in a natural gas tunnel kiln, a gas tunnel kiln and an electric burning shuttle kiln, and the burning temperature is 1230-1250 ℃.

The firing curve is as follows:

4. grinding and polishing

This procedure was done in a manual grinding and polishing machine. So that the biscuit firing product is smooth, fine and free of impurities.

5. Preparation of glaze

(1) Glaze material

The following percentage contents are taken to form the mixture ratio.

95 parts of clinker, 3 parts of Suzhou soil and 2 parts of cellulose.

(2) Formation of glaze slip

The glaze material according to the formula is filled into a wet ball mill to be finely ground (according to the grinding fineness standard, the material: ball stone: water is 1: 1.8: 0.4): 0.01 to 0.02 portion of residue of a ten-thousand-hole sieve.

(3) Iron removal sieving

And (3) after the ground glaze slurry reaches the standard after chemical analysis, passing through a set of iron-removing screening system (the iron-removing screening system comprises two 180-mesh, 200-mesh and 250-mesh three-layer vibrating screens of magnetic separators connected in series) to obtain qualified glaze slurry for later use.

6. Glaze spraying

In the working procedure, a manual glaze spraying method and a mechanical glaze spraying method can be adopted to glaze the qualified biscuit product, and the thickness of the glaze layer is controlled to be between 0.5 and 1 mm. Obtaining the qualified glazed product. Drying in a drying room, controlling the water content to be about 2 parts, and preparing for glaze firing.

7. Glaze firing

The process can be completed in a natural gas tunnel kiln, a gas tunnel kiln and an electric burning shuttle kiln, and the burning temperature is 1130 ℃ to 1150 ℃. And obtaining a qualified product.

The firing curve is as follows:

example 2

The antibacterial reinforced bone china is prepared from a blank and a glaze, wherein the blank comprises the following components in parts by weight: 43 parts of bone carbon, 22 parts of wulan tea crystal stone, 18 parts of Pingting trilobal gangue and 17 parts of Pingting dry surface; the glaze comprises, by weight, 95 parts of frit, 3 parts of perennial land and 2 parts of cellulose, and the preparation method is the same as example 1.

Example 3

The antibacterial reinforced bone china is prepared from a blank and glaze, wherein the blank comprises the following components in parts by weight: 40 parts of bone carbon, 22 parts of wulan tea crystal stone, 23 parts of Pingding trilobate waste rock and 15 parts of Pingding dry surface; the glaze comprises, by weight, 95 parts of frit, 3 parts of Pingting dry surface and 2 parts of cellulose, and the preparation method is the same as that of example 1.

The antibacterial bone china prepared in the above example 1 was sent to the national ceramic testing key laboratory alliance national building sanitary ceramic testing key laboratory foshan customs integrated technology center for antibacterial testing. The number of samples is 12, and the specification of the samples is 50mm multiplied by 50 mm; the inspection date is 2020-05-12 to 2020-05-17, and the inspection basis is as follows: JC/T897-2014 antibacterial ceramic product' test result is as follows:

the wulan tea spar used in the above examples was prepared from granite formed two hundred million years ago by the following steps: (1) transporting the mine raw ore to an open-air storage yard, homogenizing and mixing for the first time, and then entering a coarse crushing production line;

(2) coarse crushing ore blocks smaller than 300mm by a frequency crusher, stacking again by a forklift for second homogenization and mixing, then crushing in a middle stage, conveying the material smaller than 100mm to a hydraulic cone crusher by a belt, and continuously and uniformly mixing ore bodies from large to small in the whole production process through each working section to achieve stable material components;

(3) materials smaller than 30mm are conveyed to a high-speed impact sand making machine by a belt, the conventional sand making machine achieves the purpose of crushing by mechanical collision, the project is to process mica in a mineral body in a way of wall breaking, separation measuring, separation and enrichment by adopting a self-contained technology, the traditional turbine cavity wall is made of high manganese alloy wear-resistant materials to achieve the purpose of impact crushing of the materials, the project improves equipment without a lining plate in a cavity, the materials are naturally stacked into a surface, the diameter of a feed inlet is larger than 150mm, the material is directly communicated with the center end of a high-speed rotating turbine, when the materials enter the center end of the turbine, the materials are uniformly distributed to each emission flow channel of an impeller by a distribution cone in the center of the impeller, a wear-resistant alloy projection plate is arranged at the emission flow channel opening, the impeller projects the materials at the rotating speed of 6575m and impacts the materials on the stacking inclined plane of the cavity to generate strong mutual collision among the materials, so as to keep the magnetic mica in the material in the original state; an impeller grading system is improved at the top of a sand making machine body and is integrated into a machine, mica and amorphous light substances in the materials are subjected to collision wall breaking, separation and disintegration, and the ultrafine and light amorphous substances in the materials are enriched in a dust collecting system through a grading impeller and a draught fan system;

(4) materials smaller than 5mm are conveyed to a material collecting bin through a belt to be stored, are uniformly mixed for the fourth time, are ground by a lifter to a wet continuous ball mill, the ball mill is in metal-free contact grinding, the lining of the mill is a corundum lining plate, a grinding medium is a corundum ball, the materials with the grain size smaller than 26 meshes are ground by the ball mill and enter a desliming system, the desliming of the materials smaller than 325 meshes enters a thickener system in an overflow mode, the materials larger than 325 meshes enter a hindered settling grading system, and the materials larger than 50 meshes return to the ball mill system; the separated 5-0325-mesh material enters a magnetic separation system;

(5) the separated 50-325 mesh material passes through a multi-stage magnetic separation system, and then the ceramic standard raw material, namely the Wulan tea stone functional material enters a packaging system.

The performance mechanism of the Wulan tea crystal stone for preparing the ceramic is discussed:

1) with respect to strength it was first discovered that wulan tea stones significantly improve the strength of ceramic materials, which for domestic porcelain is focused on impact resistance. According to the test result, the impact strength of the central part is improved by more than one time when the proportion of the impact strength of the central part is 25%, the impact strength of the edge is improved by more than two times, and the bending strength of the bricks is the focus of attention and is improved by more than 10%. This is thought to be due to the various rare earth-like trace elements contained in the wulan tea stones, especially La ₂ O ₃ ，Sm ₂ O ₃ ，Y ₂ O ₃ Is an excellent substance, can improve the wettability of multiple components in the material, reduce the sintering point and promote Al ₂ O ₃ And SiO ₂ The reaction between the particles and the liquid phase with low melting point is formed, and the filling of substances among the particles to the pores can be promoted through the capillary action among the particles, so that the porosity of the material is reduced, and the density is improved. This analysis was validated as various products showed very low water absorption in this project. Meanwhile, the ion radius of the trace rare earth oxide is much larger than that of the ceramic material researched by us, except that a small part of the trace rare earth oxide participates in solid melting, most of the trace rare earth oxide mainly exists at the phase boundaries between a crystal phase and between glass and the crystal phase, and large ions on the phase boundaries like nails nailed on a glass network hinder the uneven structure caused by the abnormal growth of the crystal on one hand, and limit the migration and crystallization of amorphous substances to the crystal on the crystal boundary on the other hand, and reduce the migration rate of the crystal boundary. And a part of rare earth oxide is fused into the glass phase, so that the strength of the glass is improved, and the overall mechanical property of the material is improved.

2) Discussion about antibacterial property, far infrared and negative ion mechanism

The existing inorganic antibacterial agents are basically divided into two types, one is a metal ion taking a metal ion as an active component, such as Ag ⁺ 、Zn ²⁺ ，Cu ²⁺ (ii) a Another class is oxide photocatalysts, e.g. TiO ₂ The action mechanisms of ZnO, MgO and the like are roughly as follows, the first type is a contact type reaction, namely metal ions are firmly adsorbed on cell membranes by virtue of charge acting force and then penetrate cell walls to enter cells, so that bacterial proteins are solidified, the cells lose division and proliferation capacity and die, and meanwhile, the metal ions can also damage a microorganism electron transmission system, a respiratory system and a substance transmission system. b, photocatalytic reaction, under the action of light, metal ions can be excited to generate electron transfer, and O in water and air adsorbed on the surface of the glaze layer ₂ Production of-OH and O ₂ ^- They destroy the proliferation ability of bacteria in a short time, and inhibit or kill bacteria. The first class of antimicrobial agents generally requires an active carrier to carry the metal ions, such as zeolites, activated carbon, silica gel, phosphates, etc., as the metal ion type carrier. The second category of oxide photocatalytic antibacterial agents is primarily redox reactions under the action of light, such as TiO ₂ Under ultraviolet irradiation, Ti ³⁺ With Ti ⁴⁺ Electron transfer occurs, and a large number of negative oxygen ions and free radicals OH with extremely strong chemical activity are generated on the surface of the carbon dioxide, and when the free radicals contact with microorganisms, the carbon dioxide is oxidized into CO ₂ And HO, thereby performing a sterilization effect in a short time. Both of these antibacterial agents are limited in terms of use because they require the action of light in addition to the contact reaction in the first type, and particularly, the second type of oxide photocatalytic type requires irradiation with high-energy light such as ultraviolet light or near ultraviolet light.

In order to expand the photoresponse range of the antibacterial agent and enable the antibacterial agent to continuously play an antibacterial role under visible light or no light conditions, a great deal of research work is carried out by technical workers in recent years, a rare earth activation and compounding technology is adopted, so that a new energy level is added on the surface of a metal oxide photocatalytic material, multiband photocatalytic reaction under the conditions of visible light and ultraviolet light is realized, the generation capacity of free radicals is improved, and the function of the material is enhanced through a photocatalysis and rare earth valence-change synergistic component.

All products developed by the invention do not need to be added with any antibacterial agent. Conventional chemical analysis and X fluorescence spectrum analysis in the components of the blank and glaze do not have Ag ions, so the invention does not belong to the first type of contact participation reaction type antibacterial mechanism, but because of the existence of rare earth elements with rich species in the wulan tea crystalloid and the existence of magnesium oxide, zinc oxide, titanium oxide, calcium oxide, berkelium oxide, iron oxide and a plurality of trace oxides with relatively large atomic weight in the glaze of the ceramic blank, the surface energy level can be improved under the excitation of the rare earth elements, and the same action and mechanism of a second type of antibacterial agent can also be generated. In addition, as mentioned above, the various rare earth elements after sintering enter into amorphous states, namely crystals and crystal boundaries, and a large amount of rare earth element oxides in the crystal boundaries inhibit the migration of the crystals, so that the whole material is in a high energy state, so that the ceramic material prepared by taking wulan tea crystal as a main raw material is an 'energy porcelain', and metal ions in the ceramic material can release certain energy waves outwards through vibration, coupling, rotation and the like among the ions without special excitation conditions. Due to the fact that the types of the contained rare earth elements are various, the rare earth elements enter an aluminosilicate structure due to the special electronic layer structure of the elements, and the materials show certain particularity in the aspects of light and electricity under the synergistic effects of hybridization among orbitals, entanglement of electronegativity among orbitals, mutual activation and the like, and the complex system action is reflected on the surface, such as the generation of far infrared rays, the increase of surface free radicals, the generation of negative ions and the like. We believe this is the primary antimicrobial mechanism for this project.

In addition, a mechanism is discussed here, which is based on the analysis result of trace elements in wulan tea spar, that rubidium, a light metal with a content of more than 195pm, is a very strong photoelectric material, and can release electrons under normal visible light, and if it participates in the reaction of aluminosilicate, does it have the function? If so, nano-TiO-like substances are generated on the surface of the material ₂ Effect of the photosensitive material. Adding multiple kinds of diluentDue to the excitation effect of the earth element, rubidium in the material can generate escape of electrons in a normal state, electrons on a valence band can easily jump to a conduction band, positive charge holes are left, and c and H can be in contact with O adsorbed on the surface of the material ₂ OH and water to produce OH and O ₂ And H ₂ O ₂ Etc., OH has oxidizing properties and H ₂ O ₂ (active oxygen, atomic oxygen) has stronger oxidizing property, O ₂ ^- It has strong reducibility, which is another mechanism for generating antibacterial and anion functions. The method is limited by the technical level and detection means, and is not supported by theory and data, but only discussed.

3) Concerning the aspect of easy cleaning

The Umbelliferae tea spar ceramic has the advantages that the Umbelliferae tea spar ceramic can be easily cleaned as long as the blank body contains enough amount of Umbelliferae tea spar components, and the blank body is a high-energy substance after being fired, so that the stronger far infrared ray function and free radicals are changed from 'macromolecules' into 'micromolecules' (the molecular accumulation degree is reduced), the surface tension of water is reduced, the wettability on the surface of the material is enhanced, and the easy cleaning effect is generated. In addition, the existence of rare earth elements forms O2 and-OH on the surface, which is also helpful for wetting the joint surface of the product and the water, thus enhancing the easy cleaning property. At present, the index of easy cleaning is not based on a test method and a standard, the aspect is only the respective experience of users, how to quantify the concept needs further work, and reference can be made to only determine the wetting angle of water after contacting with a product.

Claims

1. The antibacterial reinforced bone china is characterized by being prepared from a blank and a glaze, wherein the blank comprises the following components in parts by weight: 40-43 parts of bone carbon, 22-25 parts of oolong tea crystal, 18-33 parts of Pingding three-flower gangue and 12-18 parts of Pingding dry flour; the glaze comprises, by weight, 95 parts of frit, 3 parts of Pingding dry surface and 2 parts of cellulose; the chemical composition of the Pingding three-flower gangue is SiO ₂ 70 parts of Al ₂ O ₃ 25 parts of Fe ₂ O ₃ 0.14 part of TiO ₂ 0.03 part, CaO0.28 part, MgO0.5 part, K ₂ O2.1 parts、Na ₂ 0.3 part of O and 1.7 parts of ignition loss; the chemical composition of the flat dry surface is SiO ₂ 46.5 parts of Al ₂ O ₃ 39.7 parts, CaO0.37 parts, MgO0.18 parts and 13.3 parts of ignition loss.

2. The antibacterial reinforced bone china according to claim 1, which is prepared from a blank and glaze, wherein the blank comprises the following components in parts by weight: 43 parts of bone charcoal, 22 parts of Wulan tea crystal stone, 18 parts of Pingding three-flower gangue and 17 parts of Pingding dry surface.

3. The antibacterial reinforced bone china according to claim 1, which is prepared from a blank and glaze, wherein the blank comprises the following components in parts by weight: 40 parts of bone carbon, 22 parts of wulan tea crystal stones, 23 parts of Pingding three-flower waste rocks and 15 parts of Pingding dry noodles.

4. The preparation method of the antibacterial reinforced bone china according to claim 1, characterized by comprising the following steps:

step three, spraying glaze on the biscuit firing product obtained in the step one by using the standby glaze slip prepared in the step two, and firing after glaze spraying to obtain the antibacterial reinforced bone china;

the biscuiting is finished in a natural gas tunnel kiln, a gas tunnel kiln or an electric-burning shuttle kiln, the burning temperature is 1230-1250 ℃, and the burning curve is as follows: room temperature-200 deg.C, 60 min; at 200-400 deg.c for 90 min; 400-600 ℃ for 100 minutes; 600-900 ℃ for 120 minutes; 900-1000 ℃ for 40 minutes; 90 minutes at 1000-1200 ℃; 1200-1250 ℃ for 40 minutes; keeping the temperature for 2 hours, and cooling to 700 ℃ within two hours;

sintering after glaze spraying in a natural gas tunnel kiln, a gas tunnel kiln or an electric-sintering shuttle kiln at the sintering temperature of 1130-1150 ℃ to obtain a qualified product; the firing curve is as follows: room temperature-200 deg.C, 60 min; at 200-400 deg.c for 90 min; 400-600 ℃ for 100 minutes; 600-900 ℃ for 120 minutes; 900-1000 ℃ for 60 minutes; 90 minutes at 1000-1150 ℃; keeping the temperature for 1 hour, and cooling to 700 ℃ for two hours.