A film-forming, easily removable, low-irritation tooth whitening gel and a method of making the same

Abstract

The application discloses a film-forming easy-to-remove low-irritation tooth whitening gel and a preparation method thereof. The film-forming easy-to-remove low-irritation tooth whitening gel comprises 1-30% of a film-forming agent, 1-15% of a plasticizer, 0.1-15% of a peroxide, 0.1-15% of a regulator and 40-95% of a volatile solvent in percentage by mass. The preparation method comprises the following steps: uniformly mixing raw materials including the film-forming agent, the plasticizer, the peroxide, the regulator and the volatile solvent to obtain the film-forming easy-to-remove low-irritation tooth whitening gel. The tooth whitening gel has better film-forming property, lower irritation, better safety in use, better whitening effect and better removal after use, and does not use a carboxyl group as an adhesion group by jointly matching the film-forming agent and the plasticizer.

Description

Technical Field

[0001] This invention relates to the field of dental whitening gel technology, specifically to a low-irritation teeth whitening gel that forms a film that is easy to remove and its preparation method. Background Technology

[0002] With the development of teeth whitening technology, whitening gels in the form of dried films have received more attention, as they have the advantage of greatly reducing the probability of the gel being accidentally swallowed.

[0003] There are already some existing technologies for whitening gels. For example, the patent specification with publication number CN115919684A discloses a kind of teeth whitening gel and its preparation method. The gel includes the following raw materials in parts by weight: peroxide: 5-10 parts; binder: 20-40 parts; thickener: 5-10 parts; desensitizing agent: 0.5-2 parts; catalyst: 0.01-0.1 parts; water: balance; the binder is silicone-modified acrylic resin.

[0004] Existing whitening gels have limited applications due to their high irritation and the fact that they adhere firmly to teeth after forming a film and are difficult to remove.

[0005] The applicant previously filed a Chinese invention patent application (publication number CN121015485A) entitled "A Teeth Whitening Gel and Its Preparation Method Thereof". This patented technology does not use carboxyl groups as adhesive groups, so the irritation of the teeth whitening gel is significantly reduced and the removability of the teeth whitening gel after use is greatly improved. However, the film formed by the teeth whitening gel is still brittle and still needs to be removed by brushing.

[0006] The existing mechanism by which whitening gels adhere to teeth is generally based on intermolecular forces or hydrogen bonds between the polar groups of the polymer side chains and the tooth surface. However, this has several drawbacks in practice: 1. After drying and forming a film, the sustained-release film becomes brittle and lacks toughness, resulting in fragments constantly falling into the mouth.

[0007] 2. The force exerted on the teeth is greater than actually needed, which results in spots remaining on the tooth surface that cannot be removed.

[0008] 3. The polar groups, especially carboxyl groups, of whitening gels are the main source of irritation to the oral cavity or mucous membranes. The high irritation limits the application of higher concentrations of active ingredients, resulting in a low overall concentration of active ingredients and a prolonged treatment time.

[0009] In fact, besides polar groups, increasing the contact area can also provide sufficient adhesion at the interface. Summary of the Invention

[0010] This invention provides a low-irritant teeth whitening gel that forms a film and is easy to remove, and its preparation method. It can be used for teeth whitening. When using it, the teeth whitening gel is applied to the teeth, dries to form a film, and is removed after a period of time.

[0011] Compared to existing technologies, this invention first uses a film-forming agent with lower polarity or even complete non-polarity, such as ethyl cellulose. Then, a compatible plasticizer is added to soften it. Therefore, when the whitening gel of this invention is applied to the tooth surface, it can further penetrate into the gaps and rough areas of the teeth, greatly increasing the contact area between the gel and the teeth. This produces the following effects: 1. Generate sufficient adhesion to allow the gel or the sustained-release film formed after drying to adhere to the tooth surface for a long time.

[0012] 2. Due to the increased contact area with teeth, the whitening active ingredients work better on the teeth, increasing the whitening effect.

[0013] 3. By not relying on polar groups such as carboxyl groups, it reduces the irritation to teeth and mucous membranes, which can further increase the concentration of active ingredients, improve patient acceptance, and thus reduce treatment time.

[0014] 4. Plasticizers soften the film-forming agent, and the slow-release film formed after drying is flexible and can be peeled off in one piece without brushing your teeth.

[0015] 5. Without relying on polar groups, the interaction force between the film-forming agent molecules and the tooth surface is lower, far lower than the interaction force between molecules. Therefore, it can be guaranteed that there is no residue of film-forming agent macromolecules after removal.

[0016] The specific technical solution is as follows: In a first aspect, the present invention provides a low-irritant teeth whitening gel that is easy to remove and forms a film. The low-irritant teeth whitening gel that is easy to remove and forms a film comprises, by weight percentage, 1% to 30% film-forming agent, 1% to 15% plasticizer, 0.1% to 15% peroxide, 0.1% to 15% regulator and 40% to 95% volatile solvent.

[0017] This invention relates to a teeth whitening gel that uses a film-forming agent and a plasticizer as film-forming components. The film is formed by the combined use of the film-forming agent and the plasticizer, with peroxide as the active ingredient. The adhesion mechanism of this teeth whitening gel is that the plasticizer softens the film-forming agent, increasing the molecular mobility, thereby penetrating into the gaps, depressions, and rough areas of the tooth surface. This increases the intermolecular forces with the teeth, resulting in adhesion. Unlike existing technologies that rely on the polar groups on the surface of the film-forming agent to adhere the gel to the teeth, non-polar film-forming agents such as ethyl cellulose are less irritating, can be removed from the teeth in one piece after use, leaving no residue, and are more convenient to use.

[0018] The film-forming, easily removable, low-irritant teeth whitening gel contains a film-forming agent accounting for 1% to 30% by mass, for example, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, etc.

[0019] The plasticizer in the film-forming, easily removable, low-irritation teeth whitening gel is 1% to 15% by mass, for example, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, etc.

[0020] The composition of the easily removable, low-irritation teeth whitening gel contains peroxides at a mass percentage of 0.1% to 15%, for example, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, etc.

[0021] The film-forming, easily removable, low-irritant teeth whitening gel contains a modifier at a mass percentage of 0.1% to 15%, for example, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, etc.

[0022] The composition of the easily removable, low-irritation teeth whitening gel contains volatile solvents at a mass percentage of 40% to 95%, such as 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, etc.

[0023] In some preferred embodiments, the film-forming, easily removable, low-irritant teeth whitening gel contains a total mass percentage of 100% for the film-forming agent, the plasticizer, the peroxide, the regulator, and the volatile solvent.

[0024] In some preferred embodiments, the film-forming, easily removable, low-irritation teeth whitening gel comprises a hydrophobic polymer material that is soluble in the volatile solvent but insoluble in water, and contains polar and / or non-polar functional groups. Exemplary examples include one or more of ethyl cellulose, acrylate copolymers, vinyl acetate copolymers, polymethacrylic acid, and copovidone. More preferably, it contains only non-polar functional groups, and even more preferably, it includes ethyl cellulose.

[0025] If only ethyl cellulose is used as a single film-forming agent and no plasticizer is used, the resulting whitening gel cannot effectively adhere to the teeth and is brittle after drying, easily breaking into small pieces and unable to form large sheets.

[0026] In some preferred embodiments, the easily removable, low-irritation teeth whitening gel includes a plasticizer comprising a substance that softens the film-forming agent by physically reducing the intermolecular forces of the film-forming agent. The plasticizer of this invention can lower the melting temperature of the film-forming agent (polymer), improve its fluidity and softness, and by intercalating between the molecular chains of the film-forming agent, weaken the intermolecular forces (van der Waals forces), thereby increasing the mobility of the film-forming agent molecular chains. This reduces the glass transition temperature (Tg), melt viscosity, and hardness of the material, making it more deformable, while simultaneously improving the material's ductility, softness, impact resistance, and cold resistance.

[0027] Furthermore, the plasticizer includes high-boiling-point, low-volatility small-molecule organic compounds (liquid or low-melting-point solids), which have good compatibility with film-forming agents and other components, and can be uniformly dispersed and stably present in the whitening gel for a long time.

[0028] More preferably, the plasticizer includes one or more of phthalimide peroxyhexanoic acid (PAP), dioctyl phthalate, dioctyl terephthalate, triethyl acetyl citrate, and triethyl citrate. More preferably, it includes at least one of triethyl citrate and PAP. In this case, PAP acts as a plasticizer and also functions as an active ingredient to a certain extent, which can make the color difference of teeth change more significantly after using whitening gel and make the whitening effect more obvious.

[0029] In some preferred embodiments, the film-forming, easily removable, low-irritation teeth whitening gel contains at least one of hydrogen peroxide, urea peroxide, and an aqueous solution containing hydrogen peroxide and / or urea peroxide. More preferably, the aqueous solution containing hydrogen peroxide and / or urea peroxide has a mass fraction of 10% to 60%, for example, 20%, 25%, 30%, 35%, 40%, 50%, etc.

[0030] In this invention, the addition of a regulator can improve the physicochemical properties of the teeth whitening gel.

[0031] In some preferred embodiments, the film-forming, easily removable, low-irritation teeth whitening gel includes a modifier comprising one or more of a thickener, a flavoring agent, and other functional ingredients.

[0032] In some preferred embodiments, the film-forming, easily removable, low-irritant teeth whitening gel includes a thickener comprising one or more of hydroxyethyl cellulose, povidone, polyacrylic acid, rosin, and frankincense, and more preferably hydroxyethyl cellulose.

[0033] In some preferred embodiments, the composition of the easily removable, low-irritant teeth whitening gel includes 1% to 15% of the thickener by weight percentage.

[0034] In some preferred embodiments, the film-forming, easily removable, low-irritation teeth whitening gel includes at least one of sugars and flavorings as the flavoring agent.

[0035] In some preferred embodiments, the easily removable, low-irritation teeth whitening gel contains sugars including one or more of sucralose, xylitol, saccharin, sorbitol, lactitol, and mannitol, with sucralose being a more preferred ingredient.

[0036] In some preferred embodiments, the film-forming, easily removable, low-irritation teeth whitening gel contains one or more of the following fragrances: peppermint, sweet orange, aloe vera, watermelon, Longjing tea, and passion fruit, with peppermint being a more preferred option.

[0037] In some preferred embodiments, the film-forming, easily removable, low-irritant teeth whitening gel comprises 0.1% to 3% of the flavoring agent by weight percentage.

[0038] In some preferred embodiments, the film-forming, easily removable, low-irritation teeth whitening gel includes D-panthenol as one of its other active ingredients.

[0039] In some preferred embodiments, the composition of the easily removable, low-irritation teeth whitening gel includes 0.5% to 5% of the other active ingredients by weight percentage.

[0040] In some preferred embodiments, the film-forming, easily removable, low-irritant teeth whitening gel includes a volatile solvent capable of dissolving the film-forming agent and the plasticizer, more preferably including at least one of ethanol, ethyl acetate, and n-hexane, and even more preferably including ethanol.

[0041] In some preferred embodiments, the viscosity of the easily removable, low-irritation teeth whitening gel is 10 to 100,000 cps.

[0042] In a second aspect, the present invention provides a method for preparing the easily removable, low-irritant teeth whitening gel described in the first aspect, comprising: mixing raw materials including a film-forming agent, a plasticizer, a peroxide, a regulator and a volatile solvent to obtain the easily removable, low-irritant teeth whitening gel.

[0043] In some preferred embodiments, in the method for preparing the easily removable, low-irritant teeth whitening gel, the amount of the volatile solvent used during the mixing of raw materials is in excess, and the volatile solvent is allowed to evaporate after the raw materials are mixed until the mass of the resulting mixture reaches the required mass.

[0044] In some preferred embodiments, the method for preparing the easily removable, low-irritant teeth whitening gel involves first dissolving the plasticizer in the volatile solvent to form a homogeneous solution, and then mixing the solution with the film-forming agent, the peroxide, and the regulator to obtain the easily removable, low-irritant teeth whitening gel.

[0045] Compared with the prior art, the beneficial effects of this invention are as follows: The teeth whitening gel of the present invention forms a film by combining a film-forming agent and a plasticizer. It does not require the use of carboxyl groups as adhesive groups, resulting in better film-forming properties, lower irritation, safer use, better whitening effect, and easier removal after use. Attached Figure Description

[0046] Figure 1 This is a photograph of the teeth whitening gel prepared in Example 1 after it has been removed from the teeth.

[0047] Figure 2 This is a photograph of the teeth whitening gel prepared in Example 2 after it was applied to a cow's tooth and then removed. Detailed Implementation

[0048] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention.

[0049] Unless otherwise specified, the operating methods in the following examples are generally performed under conventional conditions or as recommended by the manufacturer.

[0050] Example 1: A low-irritation teeth whitening gel that forms a film and is easy to remove, the preparation method of which includes: Ethyl cellulose, triethyl citrate, hydrogen peroxide aqueous solution (hydrogen peroxide mass fraction 50%) and D-panthenol are added to a slightly excess of anhydrous ethanol and stirred for 2 hours to dissolve. After dissolution, peppermint flavoring is added and stirring is continued to allow the ethanol to evaporate until the mass of the mixture reaches the desired mass, thus obtaining the desired teeth whitening gel.

[0051] By weight percentage, the composition of the easily removable, low-irritation teeth whitening gel in this embodiment is as follows: 15% film-forming agent ethyl cellulose, 7% plasticizer triethyl citrate, 3% hydrogen peroxide, 3% water, 0.5% regulator D-panthenol, 0.4% regulator peppermint flavor, and 71.1% volatile solvent ethanol.

[0052] Figure 1 The photo shows the teeth after using the low-irritation teeth whitening gel of Example 1, which forms a film that is easy to remove. As you can see, the slow-release film formed by the teeth whitening gel of the present invention after drying is flexible and can be peeled off from the teeth in one piece without any residue. It is also more convenient to use and can be removed without brushing.

[0053] Example 2: A low-irritation teeth whitening gel that forms a film and is easy to remove, the preparation method of which includes: Add phthalimide peroxyhexanoic acid to a slightly excess of anhydrous ethanol, stir for 0.5 hours or sonicate at 40°C to dissolve. After dissolving, add ethyl cellulose, hydrogen peroxide aqueous solution (hydrogen peroxide mass fraction 50%) and D-panthenol, stir for 2 hours to dissolve, then add peppermint flavoring and continue stirring to allow the ethanol to evaporate until the mass of the mixture reaches the desired mass, thus obtaining the desired teeth whitening gel.

[0054] By weight percentage, the composition of the easily removable, low-irritation teeth whitening gel in this embodiment is as follows: 13% film-forming agent ethyl cellulose, 5% plasticizer phthalimide peroxyhexanoic acid, 3% hydrogen peroxide, 3% water, 0.5% regulator D-panthenol, 0.4% regulator peppermint flavor, and 75.1% volatile solvent ethanol.

[0055] Figure 2 The photo shows the easy-to-remove, low-irritation teeth whitening gel of Example 2 after it was applied to a cow's tooth and then peeled off. It also shows that the slow-release film formed after the teeth whitening gel of the present invention dries is flexible and can be peeled off from the tooth in one piece without any residue. The process is more convenient and can be removed without brushing.

[0056] Table 1 shows the average color difference change of extracted bovine teeth after staining for four days following Examples 1, Examples 2, and the commercially available product (Colgate Teeth Whitening Essence Pen). Each sample consisted of four bovine teeth. In Example 2, phthalimide peroxyhexanoic acid (PAP) acted as both a plasticizer and, to some extent, as an active ingredient, resulting in a greater color difference change and a more pronounced whitening effect.

[0057] Table 1 The formula for calculating the color difference change ΔE is as follows: ΔE=[(L-L')^2+(a-a')^2+(b-b')^2]^0.5, where L and L' represent the brightness of the tooth surface before and after using whitening gel, respectively, which is an indication of the depth of black and white, and are positive. The larger the value, the whiter (brighter), and the smaller the value, the darker (darker). a, a', b, and b' represent the chromaticity. Specifically: a and a' represent red and green, respectively, corresponding to before and after using whitening gel. Positive values ​​indicate a reddish tint, and negative values ​​indicate a greenish tint; b and b' represent yellow and blue, respectively, corresponding to before and after using whitening gel. Positive values ​​indicate a yellowish tint, and negative values ​​indicate a bluish tint.

[0058] Furthermore, it should be understood that after reading the above description of the present invention, those skilled in the art can make various alterations or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims.

Claims

1. A film-forming, easily removable, low-irritation teeth whitening gel, characterized in that, The film-forming, easily removable, low-irritant teeth whitening gel, by weight percentage, comprises 1% to 30% film-forming agent, 1% to 15% plasticizer, 0.1% to 15% peroxide, 0.1% to 15% regulator, and 40% to 95% volatile solvent.

2. The film-forming, easily removable, low-irritation teeth whitening gel according to claim 1, characterized in that, The film-forming agent comprises a hydrophobic polymer material that is soluble in the volatile solvent, insoluble in water, and contains polar and / or non-polar functional groups.

3. The film-forming, easily removable, low-irritation teeth whitening gel according to claim 1, characterized in that, The plasticizer includes substances that soften the film-forming agent by physically reducing the intermolecular forces of the film-forming agent.

4. The film-forming, easily removable, low-irritation teeth whitening gel according to claim 1, characterized in that, The peroxide includes at least one of hydrogen peroxide, urea peroxide, and an aqueous solution containing hydrogen peroxide and / or urea peroxide.

5. The film-forming, easily removable, low-irritation teeth whitening gel according to claim 1, characterized in that, The regulator includes one or more of the following: thickeners, flavoring agents, and other functional ingredients; The thickener includes one or more of hydroxyethyl cellulose, povidone, polyacrylic acid, rosin, and frankincense; The flavoring agent includes at least one of sugars and flavorings; The sugars include one or more of sucralose, xylitol, saccharin, sorbitol, lactitol, and mannitol; The flavorings include one or more of the following: peppermint flavoring, aloe vera flavoring, watermelon flavoring, Longjing tea flavoring, sweet orange flavoring, and passion fruit flavoring; The film-forming, easily removable, low-irritant teeth whitening gel comprises, by weight percentage, 0.1% to 3% of the flavoring agent; The other active ingredients include D-panthenol.

6. The film-forming, easily removable, low-irritation teeth whitening gel according to claim 1, characterized in that, The volatile solvent includes materials capable of dissolving the film-forming agent and the plasticizer.

7. The film-forming, easily removable, low-irritation teeth whitening gel according to claim 1, characterized in that, The viscosity of the easily removable, low-irritation teeth whitening gel is 10~100000 cps.

8. The method for preparing the easily removable, low-irritation teeth whitening gel according to any one of claims 1-7, characterized in that, include: The raw materials, including film-forming agents, plasticizers, peroxides, regulators, and volatile solvents, are mixed to obtain the low-irritation teeth whitening gel that forms an easily removable film.

9. The preparation method according to claim 8, characterized in that, During the mixing process of the raw materials, the amount of the volatile solvent is in excess. After the raw materials are mixed, the volatile solvent is allowed to evaporate until the mass of the resulting mixture reaches the required mass.

10. The preparation method according to claim 8 or 9, characterized in that, First, the plasticizer is dissolved in the volatile solvent to form a homogeneous solution. Then, the solution is mixed with the film-forming agent, the peroxide, and the regulator to obtain the easily removable, low-irritant teeth whitening gel.

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