Preparation method of silicon dioxide for toothpaste with anti-allergy effect

Abstract

The preparation method comprises the following steps: firstly, adding process water and dilute water glass into a reaction kettle, adding dilute acid to generate a silicon dioxide core, adding an anti-allergy solution, uniformly stirring, carrying out acid-base parallel flow reaction, and continuing to add dilute acid for acidification; and carrying out filter pressing, washing, pulping, drying and crushing to obtain silicon dioxide powder. The toothpaste prepared from the silicon dioxide disclosed by the invention can enhance the anti-allergy ability of dentin, block tubules in the dentin, reduce the permeability of the dentin and improve the transmission of nerve pulses; the preparation method has the advantages that the process is simple, safety and non-toxicity are achieved, the surface of the product can effectively bear potassium ions and strontium ions, the prepared silicon dioxide can relieve tooth sensitivity while keeping good thickening and friction effects of the silicon dioxide, meanwhile, other anti-sensitive components do not need to be added in a toothpaste formula, and the production cost of the toothpaste is reduced.

Description

Technical Field

[0001] The invention relates to the field of silicon dioxide preparation, and in particular to a method for preparing silicon dioxide for toothpaste with anti-allergic effect. Background Art

[0002] Tooth sensitivity is the phenomenon in which teeth experience numbness and pain when exposed to cold, heat, sourness or sweetness. It is mainly due to tooth erosion, gum atrophy, exposed tooth roots, etc., which expose the dentin. Under the stimulation, the cytoplasmic processes of the dentin cells transmit and cause sensitive symptoms. With the increase of age, the frequency of tooth sensitivity increases, which seriously affects people's quality of life.

[0003] The mechanism of strontium salt desensitization is: if there is a very small amount of strontium in the tooth, the desensitization ability of the dentin can be enhanced. Both enamel and dentin can absorb strontium. Strontium reacts with calcium carbonate in the tooth to form strontium carbonate, and at the same time reacts with hydroxyapatite in the dentin to form hydroxystrontium apatite, which blocks the open tubules of the dentin and plays a role in re-covering the tubules, thereby enhancing the anti-allergic ability of the teeth. Strontium can also penetrate deep into the teeth, significantly reducing the permeability of the hard tissue of the teeth, and playing an acid-resistant desensitization role.

[0004] The mechanism of potassium salt desensitization is: potassium ions entering the dentin tubules can reduce the permeability of the dentin, and have an affinity with nerve endings, inhibiting the transmission of pain signals by nerve endings through chemical reactions, thereby achieving the purpose of relieving pain.

[0005] Silica is an industrial raw material with a very wide application range. It is generally used as an abrasive in toothpaste and has both friction and thickening effects. There is no silica for toothpaste in the prior art that can relieve tooth sensitivity. If toothpaste needs to have an anti-sensitivity effect, additional anti-sensitivity ingredients need to be added. Summary of the invention

[0006] In order to overcome the above-mentioned shortcomings and deficiencies of the prior art, the object of the present invention is to provide a method for preparing silicon dioxide for toothpaste with anti-sensitivity effect, which has the advantages of significant anti-sensitivity effect, convenient adjustment of water absorption value and simple preparation process.

[0007] Another object of the present invention is to provide a toothpaste with anti-sensitivity effect.

[0008] The purpose of the present invention is achieved through the following technical solutions:

[0009] The present invention provides a method for preparing silicon dioxide for toothpaste with anti-allergic effect, comprising the following steps:

[0010] (1) adding dilute water glass with a concentration of 2-2.4 mol / L and process water in a volume ratio of (0.025-0.15):1 into a reaction kettle at a temperature of 40-80° C., and adding dilute sulfuric acid with a mass concentration of 10-18% at a uniform rate under stirring conditions to react and form a silicon dioxide core, referred to as solution A; wherein the volume ratio of dilute sulfuric acid to process water is (0.01-0.04):1;

[0011] (2) adding an anti-sensitive solution to solution A and stirring until uniformly dispersed, which is referred to as solution B; the anti-sensitive solution contains an anti-sensitive salt; the anti-sensitive salt is at least one of a potassium salt and a strontium salt;

[0012] (3) Adding dilute water glass with a concentration of 2-2.4 mol / L and dilute sulfuric acid with a mass concentration of 10-18% to solution B, maintaining the pH value at 9.5-10.5, and the co-flow time is 80-100 min to obtain material C;

[0013] (4) Adding dilute sulfuric acid with a mass concentration of 10-18% to material C until the pH value of the material is 3.5-4.5, and obtaining material D after aging;

[0014] (5) The material is filtered, washed, pulped, dried and crushed to obtain silicon dioxide for toothpaste with anti-allergic effect.

[0015] Preferably, the addition rate of the dilute sulfuric acid in step (1) is 3-5 m3 / h.

[0016] Preferably, the anti-sensitive salt is at least one of potassium nitrate, potassium chloride, potassium citrate, dipotassium glycyrrhizinate, strontium acetate and strontium chloride.

[0017] Preferably, the anti-sensitive solution contains both potassium salt and strontium salt.

[0018] Preferably, in the silicon dioxide for toothpaste having anti-sensitivity effect, the mass of the anti-sensitivity salt is 1%-5% of the mass of the silicon dioxide.

[0019] Preferably, the stirring frequency in step (1) is 35-45 Hz; the stirring frequency in step (2) is 35-45 Hz.

[0020] Preferably, the flow rate of the dilute water glass in step (3) is 8-10m3 / h, and the flow rate of the dilute sulfuric acid is 5-7m3 / h. 3 / h.

[0021] Preferably, the flow rate of the dilute sulfuric acid in step (4) is 3-4 m3 / h.

[0022] Preferably, the aging time in step (4) is 10-30 min.

[0023] The present invention also provides a toothpaste with anti-allergic effect, comprising the silicon dioxide prepared by the method for preparing silicon dioxide for toothpaste with anti-allergic effect.

[0024] In the preparation method of the present invention, the first step is to generate a silica inner core, the second step is to uniformly disperse potassium salt and strontium salt in a material reaction system, the third step is to simultaneously add sodium silicate and sulfuric acid solution, silica particles are precipitated on the inner core, and potassium salt and strontium salt are adsorbed in a flocculent structure, so that a large amount of anti-allergic substances are adsorbed in the pores of the silica particles; the fourth step is to completely acidify the silica particles, improve the dispersibility of the product, enhance the adsorption capacity, and regulate the surface properties; the silica particles produced by the method of the present invention have larger pores, can fully wrap potassium salt and strontium salt, and potassium ions and strontium ions can be precipitated in the toothpaste in the later stage; through the steps of washing, pulping, drying and the like, the damage to the spatial structure of silica can be reduced, so that the product is rich in anti-allergic ingredients.

[0025] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0026] The method for preparing silicon dioxide for toothpaste with anti-sensitivity effect of the present invention directly combines anti-sensitivity components in silicon dioxide synthesis. Compared with adding anti-sensitivity components in toothpaste production, the method has the following advantages: 1. In the synthesis process of the present invention, potassium salt and strontium salt are added, and potassium salt and strontium salt are coated by sandwich structure. The prepared silicon dioxide is rich in potassium salt and strontium salt, and the loss of anti-sensitivity components in subsequent process is effectively reduced. Long-term use of toothpaste containing such silicon dioxide for brushing teeth can continuously enter the dentinal tubules and be deposited, thereby achieving the effect of sealing the dentinal tubules, improving the conduction of nerve impulses, and reducing tooth sensitivity; 2. The preparation method of the present invention is simple in operation, convenient and quick in adjusting the water absorption value, and sufficient in anti-sensitivity components; 3. The silicon dioxide for toothpaste for alleviating tooth sensitivity provided by the present invention is applied to toothpaste, and can effectively alleviate the problem of tooth sensitivity while playing a role of friction and thickening, and there is no need to add other components for alleviating tooth sensitivity except the toothpaste formula, thereby reducing the production cost of anti-sensitivity toothpaste, and the economic and social benefits are significant. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The present invention is a flow chart of a method for preparing silicon dioxide for toothpaste with anti-sensitivity effect according to an embodiment of the present invention. DETAILED DESCRIPTION

[0028] The present invention will be further described in detail below in conjunction with examples, but the embodiments of the present invention are not limited thereto.

[0029] Embodiment 1:

[0030] The preparation method of the silicon dioxide for toothpaste with anti-allergic effect in this embodiment is as follows: Figure 1 As shown, the specific steps are as follows:

[0031] 20m 3 Volume of process water with 1.3m 3 Add 2 mol / L diluted water glass into the reactor, set the temperature to 60°C, turn on the stirring blade, keep the frequency at 40HZ, stir the material evenly, and 3 / h flow rate of 0.38m 3 , 12% mass fraction of dilute sulfuric acid, react to form a silicon dioxide core, add strontium chloride and potassium nitrate with a mass fraction of 4% of the silicon dioxide, stir at 40HZ until uniformly dispersed, and at the same time add 2mol / L dilute water glass and 12% mass fraction of dilute sulfuric acid, the dilute water glass flow rate is 9.8m 3 / h, dilute sulfuric acid 6.5m 3 / h, maintain pH value at 10.5, parallel flow time 90min, after the parallel flow ends, continue at 3.8m 3 / h flow rate, adding 12% mass fraction of dilute acid until the pH value of the material is 4.0, and aging for 20 minutes; the slurry is filtered, washed, pulped, dried, and crushed to obtain silicon dioxide powder.

[0032] Embodiment 2:

[0033] The preparation method of the silicon dioxide for toothpaste with anti-allergic effect in this embodiment is as follows: Figure 1 As shown, the specific steps are as follows:

[0034] 15m 3 Volume of process water and 1.0m 3 Add 2.2 mol / L diluted water glass into the reactor, set the temperature to 55°C, turn on the stirring blade, keep the frequency at 40HZ, stir the material evenly, and 3 / h add 15% mass fraction of dilute sulfuric acid to react and form a silicon dioxide core, add 5% of the mass of strontium chloride of the silicon dioxide, stir at 40HZ until it is evenly dispersed, and at the same time add 2.2mol / L dilute water glass and 15% mass fraction of dilute sulfuric acid, the dilute water glass flow rate is 9.2m 3 / h, dilute sulfuric acid 5.5m 3 / h, maintain pH value at 10.0, parallel flow time 90min, after the parallel flow ends, continue at 3.4m 3 / h flow rate, adding 15% mass fraction of dilute acid until the pH value of the material is 4.5, and aging for 15 minutes; the slurry is filtered, washed, beaten, dried, and crushed to obtain silicon dioxide powder.

[0035] Embodiment 3:

[0036] The preparation method of the silicon dioxide for toothpaste with anti-allergic effect in this embodiment is as follows: Figure 1 As shown, the specific steps are as follows:

[0037] 13m 3 Volume of process water and 0.8m 3 Add 2.4 mol / L diluted water glass into the reactor, set the temperature to 65°C, turn on the stirring blade, keep the frequency at 40HZ, stir the material evenly, and 3 / h add 17% mass fraction of dilute sulfuric acid to react and form a silicon dioxide core, add 5% of the mass of potassium nitrate of the silicon dioxide, stir at 40HZ until it is evenly dispersed, and at the same time add 2.4mol / L dilute water glass and 17% mass fraction of dilute sulfuric acid, the dilute water glass flow rate is 8.3m 3 / h, dilute sulfuric acid 4.5m 3 / h, maintain pH value at 9.6, parallel flow time 90min, after the parallel flow ends, continue at 3.0m 3 17% by mass dilute acid was added at a flow rate of / h until the pH value of the material was 3.5, and then aged for 10 minutes; the slurry was filtered, washed, beaten, dried, and crushed to obtain silicon dioxide powder.

[0038] Comparative Example 1:

[0039] Compared with Example 1, the material reaction steps are similar, except that no anti-sensitive solution is added during the reaction.

[0040] Comparative Example 2:

[0041] This comparative example adopts a toothpaste product in which two anti-sensitivity ingredients are directly added to the toothpaste formula.

[0042] Test method: The product needs to test the water absorption value of the product and the anti-sensitivity effect of the toothpaste product.

[0043] Test 1: Weigh 20 grams of product and test the amount of deionized water absorbed by the product

[0044] The test results are shown in the figure below:

[0045]

[0046] Test 2: The silica product of the present invention was made into toothpaste, and 100 patients with tooth sensitivity were selected, regardless of gender, and divided into 5 groups, each with 20 people. They used toothpaste A, toothpaste B, toothpaste C, toothpaste D prepared in comparative example 1, and toothpaste E prepared in comparative example 2, respectively. The use period was 3 months, and the test samples were used for normal brushing every morning and evening during the use period. After 3 months, an evaluation was conducted, and the number of effective people, ineffective people, and effective rate of each group were counted.

[0047] Toothpaste recipe:

[0048]

[0049]

[0050] Test 2 test results:

[0051] Effect evaluation Toothpaste A Toothpaste B Toothpaste C Toothpaste D Toothpaste E Obvious effect 11 8 7 1 6 Average effect 5 6 6 2 6 No effect 4 6 7 17 8 Total number of people 20 20 20 20 20 Efficiency 80％ 70％ 65％ 15％ 60％

[0052] As known from Experiment 1, the water absorption value of the silica product of the present invention can be adjusted through the process, and the operation is simple, and the water absorption value covers multiple models such as low thickening, medium thickening, and high thickening.

[0053] It can be seen from Experiment 2 that Example 1, Example 2, Example 3 and the like have obvious anti-sensitive effectiveness compared to Comparative Example 1, indicating that the silicon dioxide with anti-sensitive ingredients added is more suitable for use in anti-sensitive toothpaste than ordinary silicon dioxide. Compared with the common anti-sensitive toothpaste on the market such as Comparative Example 2, the effectiveness of the products of Example 1, Example 2, Example 3 and the like are all improved. The anti-sensitive effectiveness of Example 1 after three months reaches 80%, which is the best embodiment of the present invention.

[0054] The present invention first adds bottom water and dilute water glass to a reactor, adds dilute acid to generate a silicon dioxide kernel, adds an anti-sensitive solution composed of potassium ions and strontium ions, stirs evenly, and then performs an acid-base co-current reaction, silicon dioxide particles are precipitated, grow on the surface of the kernel in a flocculent structure, and form a silicon dioxide with a sandwich structure of a kernel plus a flocculent coating layer, the particle surface is fully combined with anti-sensitive components, and then the silicon dioxide powder is obtained by filter pressing, washing, drying, crushing, etc. By adding potassium ions and strontium ions to silicon dioxide, the toothpaste using the silicon dioxide produced by the present invention can enhance the anti-sensitivity ability of dentin, block the tubules in the dentin, reduce the permeability of dentin, and improve the transmission of nerve impulses; the method has the advantages of simple process, safety and non-toxicity, and the product surface can effectively carry potassium ions and strontium ions. The obtained silicon dioxide can relieve tooth sensitivity while retaining its own good thickening and friction effects, and at the same time, it is not necessary to add other anti-sensitive components in the toothpaste formula, thereby reducing the production cost of toothpaste.

[0055] In summary, the sandwich structure silica for anti-sensitivity toothpaste produced by the present invention can not only adjust the water absorption value of the product stably and efficiently through the process, but also has obvious anti-sensitivity effect, and does not need to add additional anti-sensitivity ingredients to the toothpaste formula, and has extremely high economic value.

[0056] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A method for preparing silicon dioxide for toothpaste with anti-allergic effect, characterized in that: The following steps are involved: (1) adding dilute water glass with a concentration of 2-2.4 mol / L and process water in a volume ratio of (0.025-0.15):1 into a reaction kettle at a temperature of 40-80° C., and adding dilute sulfuric acid with a mass concentration of 10-18% at a uniform rate under stirring conditions to react and form a silicon dioxide core, referred to as solution A; wherein the volume ratio of dilute sulfuric acid to process water is (0.01-0.04):1; (2) adding an anti-sensitive solution to solution A and stirring until uniformly dispersed, which is referred to as solution B; the anti-sensitive solution contains an anti-sensitive salt; The anti-sensitive salt is at least one of a potassium salt and a strontium salt; (3) Adding dilute water glass with a concentration of 2-2.4 mol / L and dilute sulfuric acid with a mass concentration of 10-18% to solution B, maintaining the pH value at 9.5-10.5, and the co-flow time is 80-100 min to obtain material C; (4) Adding dilute sulfuric acid with a mass concentration of 10-18% to material C until the pH value of the material is 3.5-4.5, and obtaining material D after aging; (5) The material is filtered, washed, pulped, dried and crushed to obtain silicon dioxide for toothpaste with anti-allergic effect.

2. The method for preparing silicon dioxide for toothpaste with anti-allergic effect according to claim 1, characterized in that: The addition rate of the dilute sulfuric acid in step (1) is 3-5m 3 / h.

3. The method for preparing silicon dioxide for toothpaste with anti-allergic effect according to claim 1, characterized in that: The anti-sensitive salt is at least one of potassium nitrate, potassium chloride, potassium citrate, dipotassium glycyrrhizinate, strontium acetate and strontium chloride.

4. The method for preparing silicon dioxide for toothpaste with anti-allergic effect according to claim 3, characterized in that: The anti-sensitive solution contains potassium salt and strontium salt at the same time.

5. The method for preparing silicon dioxide for toothpaste with anti-allergic effect according to claim 4, characterized in that: In the silicon dioxide for toothpaste with anti-sensitivity effect, the mass of the anti-sensitivity salt is 1%-5% of the mass of the silicon dioxide.

6. The method for preparing silicon dioxide for toothpaste with anti-allergic effect according to claim 1, characterized in that: The stirring frequency in step (1) is 35-45 Hz; the stirring frequency in step (2) is 35-45 Hz.

7. The method for preparing silicon dioxide for toothpaste with anti-allergic effect according to claim 1, characterized in that: The flow rate of the dilute water glass in step (3) is 8-10m3 / h, and the flow rate of the dilute sulfuric acid is 5-7m3 / h. 3 / h.

8. The method for preparing silicon dioxide for toothpaste with anti-allergic effect according to claim 1, characterized in that: The flow rate of the dilute sulfuric acid in step (4) is 3-4m3 / h.

9. The method for preparing silicon dioxide for toothpaste with anti-allergic effect according to claim 1, characterized in that: The aging time in step (4) is 10-30 minutes.

10. A toothpaste with anti-allergic effect, characterized in that: The invention relates to silicon dioxide prepared by the method for preparing silicon dioxide for toothpaste with anti-sensitivity effect as claimed in any one of claims 1 to 9.

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