JP4694794B2 - Dentifrice - Google Patents

Description

  The present invention relates to a dentifrice containing a wet-process silica granule, and in particular, it is possible to recognize the effect of removing dirt by the aesthetic effect of the granule and the feel of the granule in the oral cavity, and the strength that the granule is palpable in the oral cavity The toothpaste does not give an unpleasant sensation of foreign matter because it gradually disintegrates during the toothpaste process.

  Dentifrices containing granules and granular substances are conventionally known. Such granules include those containing functional materials such as drugs, enzyme agents, and abrasives, and those intended for aesthetic effects. As the binder for these granules, water-soluble binders such as methylcellulose and carboxymethylcellulose, and water-insoluble binders such as wax and ethylcellulose have been used. If the above water-insoluble binder is used, adjusting the hardness and size of the granule to such an extent that it can be touched will cause the granule to be regarded as a foreign body sensation in the oral cavity. There were problems such as being.

Therefore, the present applicant has proposed a dentifrice containing granules obtained by binding a water-insoluble powder material such as zeolite with a water-insoluble inorganic binder as a dentifrice that has solved the above-described problems (Patent Document). 1). This dentifrice is made by granulating a water-insoluble powder material with a water-insoluble binder and blending granules that maintain a certain size and strength, so that the granules can be palpated in the mouth and the effect can be recognized. In spite of this, the abrasive power is enhanced with almost no foreign material feeling and without damaging the teeth.
JP-A-1-299211

However, the granule blended in the dentifrice has a problem that it is expensive because it requires a binder in its production.
Accordingly, there is a need for a dentifrice that incorporates granules produced without the use of a binder and has the same or better performance than the above dentifrice.

  In such a situation, the present inventor has conducted intensive studies, and as a result, the wet process silica can be granulated without a binder, and the dentifrice blended with this granule can feel the granule in the oral cavity, Despite being able to recognize the effect, the present inventors have found that the foreign matter is hardly felt and the polishing power is enhanced without damaging the teeth, and the present invention has been completed.

That is, the present invention has a particle size that passes through a 30-mesh sieve (JIS standard) but does not pass through a 200-mesh sieve (JIS standard), and the disintegration strength per piece is 30 to 800 gf / mm ² . , the polishing force is less RDA value 150, BET specific surface area is Ri 150~450m ² / g der, it is provided a dentifrice comprising from 1 to 50% by weight of wet silica granules containing no binder is there.

  The wet-process silica granules used in the present invention need to have a particle size (75 to 500 μm) that passes through a 30-mesh sieve but does not pass through a 200-mesh sieve. The particle size of 75 μm or more is required to visually recognize and touch in the oral cavity, and when the particle size exceeds 500 μm, the roughness in the oral cavity becomes strong and the feeling of use becomes worse. Moreover, it is preferable that an average particle diameter is 150-250 micrometers.

The strength (hardness) of the wet-process silica granule is a strength that collapses at 30 to 800 gf / mm ² per granule, and is particularly preferably 40 to 500 gf / mm ² . If the disintegration strength per silica granule is less than 30 gf / mm ² , the polishing power is not sufficient, and if it exceeds 800 gf / mm ^{2, it} will be felt only as foreign matter and will not disintegrate even by brushing. May hurt the enamel.

  The polishing power of the wet silica granule needs to be RDA value (Radioactive Dentine Ablation values) 150 or less, and particularly preferably 100 or less. If the RDA value exceeds 150, the teeth may be cut more than necessary.

The specific surface area and pore volume of the wet silica granule by BET method are 150 to 450 m ² / g and 1 to 2.5 ml / g, respectively, for controlling the disintegration strength, medicinal components and perfume adsorption amount of the granule. Particularly preferred are 200 to 400 m ² / g and 1.5 to 2.0 ml / g.

  The wet method silica used in the present invention can be produced by a precipitation method or a gel method, for example, according to the following production method.

(1) A method in which a silica hydrosol whose pH has been adjusted in advance is suspended in a medium such as an oil having no affinity for it, solidified in the suspension, washed away to remove impurities, and then dried. .
(2) A method in which silica hydrosol is gelated by spraying it in the air, and after removing impurities by washing and drying.

  The wet-process silica granule blended in the dentifrice of the present invention may be obtained by any of these methods.

The wet-process silica granules thus obtained can be blended in various dentifrices such as toothpastes and powder dentifrices, but are particularly preferred to be blended in toothpastes in order to express the aesthetics of the granules.
The blending amount of the granules is preferably 1 to 50% by weight in the dentifrice, and particularly preferably 3 to 30% by weight.

  Since silica has a large specific surface area, adsorbing medicinal ingredients and fragrances to wet-process silica granules and blending them into dentifrices can cause the silica pieces that are disintegrated during brushing to be absorbed and remain in the oral cavity. Can be sustainedly released.

  The medicinal component is not particularly limited as long as it is used in the oral region, and examples thereof include caries preventive agents, antimicrobial agents, vitamins, enzymes, anti-inflammatory agents, and the like. Sodium fluoride, tin fluoride, sodium monofluorophosphate, vitamin E, vitamin C, dextranase, mutanase, sodium chloride, glycyrrhetinic acid, azulene, β-glycyrrhetinic acid, dihydric cholesterol, chlorhexidine, epidihydric cholesterol, Examples include isopropylmethylphenol, trichlorocarbanilide, halocarban, hinokitiol, allantoin, tranexamic acid, propolis, cetylpyridinium chloride, and the like. These can be used alone or in combination of two or more.

  Examples of fragrances include menthol and natural products including menthol; basil, camphor, caraway, cardamom, coriander, geranium, ginger, laurel, lavender, mace, nutmeg, pepper, rose, rosemary, thyme, ylang ylang, jasmine , Vanilla, hyssop, lavandin, oris, carrot seed, davana, elemi, osmantas essential oil and extract; borneol and its derivatives; heliotropin; α-, β-, γ-, δ-ionone and their derivatives; thymol, Examples include vanillin, ethyl vanillin, maltol, and ethyl maltol, and these can be used alone or in combination of two or more.

  The dentifrice of the present invention is prepared according to a conventional method, and other components blended in a normal dentifrice can be blended. For example, examples of the binder include sodium carboxymethyl cellulose, sodium polyacrylate, hydroxyethyl cellulose, thickening silica, montmorillonite, carrageenan, sodium alginate, guar gum, pectin and the like. Surfactants include acylamino acid salts such as sodium acylglutamate and sodium acylsarcosine; alkylphosphoric acid salts such as sodium lauryl phosphate; sucrose fatty acid ester, sorbitan fatty acid ester, polyoxyethylene fatty acid ester, polyoxyethylene Examples thereof include polyoxypropylene block copolymer. In addition, the same medicinal components and fragrances, wetting agents, sweetening agents, preservatives and the like as described above can be blended.

  Since the granule blended in the dentifrice of the present invention does not use a binder, it can be produced inexpensively and easily, and there is an advantage that the cost of the dentifrice can be reduced.

  Next, although an example is given and explained, the present invention is not limited to these examples.

Example 1
A silica hydrosol having a primary particle diameter of 4.0 nm was sprayed into the air to form a gel, washed with purified water, and then dried to produce wet method silica granules.

The resulting granule has a particle size that passes through a 30 mesh screen but does not pass through a 200 mesh screen (average particle size 200 μm), disintegrates when a load of 200 gf / mm ² is applied, and the polishing power is RDA The value was 60, the specific surface area was 280 m ² / g, and the pore volume was 1.90 ml / g.

  In order to evaluate the feel of the granule, the produced granule was directly blended into a dentifrice having the composition shown in Table 1. The dentifrice was left for 1 week after production to stabilize the fragrance. Thereafter, 20 panelists used this dentifrice, and immediately after that evaluated the feel of the granules. The toothbrush was a normal round cut toothbrush. Granule oral recognition and granule feel were classified as follows. The feel of the granules was evaluated by a panelist who recognized the granules in the oral cavity. The results are shown in Table 2.

(Recognition of granules in the oral cavity):
1: Recognized from the start of brushing to the end of brushing.
2: The granule was palpated in the early stages of brushing, but became untouchable during brushing.
3; The granule was not palpable.

(Granule feel):
1: Good.
2; Somewhat good.
3; Neither.
4; Somewhat bad.
5: Bad.

Test Example Dentifrice (Comparative product) containing 15.0% by weight of wet method silica having a particle size of 10 μm instead of wet method silica granules in the dentifrice shown in Table 1 (product of the present invention) and the dentifrice shown in Table 1. ) Was investigated for cleansing action. 1g of dentifrice is applied to a glass plate coated with black magic ink, brushed, and the number of times of brushing when the magic sink on the glass plate is completely removed with the naked eye (when 10 tests are performed) Average). The number of brushing was 4.7 times for the product of the present invention and 30.5 times for the comparative product.

Examples 2-4
Silica granules having the properties shown in Table 3 below were obtained, and toothpastes having the compositions shown in Table 4 were prepared. These toothpastes were both good in feel and cleansing.

Claims (2)

A silica hydrosol having a primary particle size of 4.0 nm is synthesized as a raw material by a gel method, has a particle size that does not pass through a 30 mesh sieve, but does not pass through a 200 mesh sieve, and has a disintegration strength of 30 to 800 gf. / mm ^2, the polishing force is less RDA value 150, BET specific surface area is the 150~450m ² / g, a binder wet silica granules toothpaste containing 1 to 30 wt% which does not contain . Wet silica granules, the Shirikahido b sol primary particle size 4.0nm gelled by spraying into the air, after washing to remove impurities, is synthesized by drying according to claim 1 toothpaste .