JPH0222724B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a cosmetic containing hydrophobized ultrafine particulate titanium oxide. More specifically, rutile-type titanium oxide containing 1 to 20% by weight of an inorganic oxide or inorganic hydroxide and having an average particle diameter of 10 to 30 mμ, which has been made hydrophobic, is mixed into a cosmetic base material to emit visible light. The present invention relates to a cosmetic that has good makeup retention, good dispersibility, stability, and usability and is suitable for protecting the skin from sunburn by reflecting and scattering harmful ultraviolet rays that pass through and cause sunburn. If the skin is exposed to excessive ultraviolet rays, erythema,
Blisters, edema, and subsequent pigmentation are known to occur. Ultraviolet rays are also harmful to hair, causing hair breakage and split ends. As described above, ultraviolet rays are often extremely harmful both from an aesthetic point of view and from a health point of view. 200nm to 400nm in sunlight is the ultraviolet region, and depending on the wavelength, deep ultraviolet 200nm to 280nm, medium ultraviolet rays
It is divided into three types: 280 to 320 nm and near ultraviolet rays of 320 to 400 nm.There is an ozone layer that extends 20 to 25 km in the upper layer of the atmosphere, and because this ozone absorbs ultraviolet rays well, it is actually the case that most people on earth are exposed to ultraviolet rays. What is present is part of the mid-ultraviolet rays and near-ultraviolet rays. The shortest wavelength of medium ultraviolet rays is thought to be around 295 nm. Therefore, it is appropriate to limit the ultraviolet rays that we are exposed to on a daily basis to medium and near ultraviolet rays of 295 to 400 nm. Sunburn is caused by medium ultraviolet rays (UV-B) and near ultraviolet rays (UV-A) of 295 to 400 nm, but UV
-B causes erythema on the skin and causes post-inflammatory darkening. On the other hand, UV-A has a very weak erythema-inducing power compared to UV-B, and is said to darken the skin without substantially causing erythema. As described above, mid-ultraviolet light in the range of 290 to 320 nm is said to have the strongest biological effects. Among them, 297.6nm is said to be the strongest wavelength. In order to prevent these disorders, cosmetics containing various UV absorbers have been developed and marketed, but the UV absorbers used in these products include P-aminobenzoic acid derivatives, salutyl Examples include synthetic ultraviolet absorbers such as acid derivatives, benzotriazole derivatives, benzophenone derivatives, and cinnamic acid derivatives, and inorganic pigments such as titanium oxide, zinc oxide, and iron oxide. The former type of synthetic ultraviolet absorber has problems with solubility when added in large amounts to cosmetic base materials, and is often used as a raw material for cosmetics, such as irritation to the skin, deterioration due to ultraviolet absorption, decrease in absorbing power, and coloring. There is a problem. On the other hand, the latter inorganic pigment is
Since there is little deterioration due to ultraviolet rays and it is not absorbed through the skin, there is no problem with irritation to the skin, but particles with large particle sizes (for example, 350 mμ) are in the range that blocks visible light, so they are not exposed to ultraviolet light. It has weak absorption, has too strong hiding power, and causes too much whitening or coloring, making it impossible to use it for anything other than makeup applications such as foundation creams or lipsticks. In addition, sunscreen cosmetics containing fine titanium oxide particles with an average size of 30 to 40 mμ have been proposed (Japanese Patent Publication No. 47-42502), but they have high hiding power and
The UV absorption effect, dispersibility in cosmetic base materials, usability, stability, etc. are insufficient. In view of these circumstances, the present inventors have conducted intensive research to solve the above-mentioned drawbacks, and have found that if a specific amount of titanium oxide with a limited particle size is blended into a cosmetic base, biological The strongest of the 290 to 320 nm wavelengths, which have the strongest effect and cause erythema on the skin.
The inventors have discovered that they can reflect and scatter ultraviolet rays around 297.6 nm, protecting the skin from ultraviolet rays, and can also transmit visible rays well, and based on this knowledge, they have completed the present invention. That is, the present invention contains rutile-type titanium oxide containing 1 to 20% by weight of an inorganic oxide or inorganic hydroxide and having an average particle diameter of 10 to 30 mμ, which has been made hydrophobic.
The object of the present invention is to provide a cosmetic composition characterized by containing 0.1 to 40% by weight. Cosmetics containing the specific titanium oxide of the present invention include:
As mentioned above, by transmitting visible light and reflecting and scattering harmful ultraviolet rays that cause sunburn, it not only protects the skin from sunburn, but also has the effect of long-lasting makeup and excellent dispersibility, stability, and usability. . The titanium oxide used in the present invention is preferably rutile-type titanium oxide, and the effect is more pronounced than that of titanium oxide with other crystal structures. The average particle size of the rutile-type titanium oxide that can be applied to the present invention is 10 to 30 mμ. The titanium oxide can be produced by a general method for producing rutile-type titanium oxide. for example,
This is a method of hydrolyzing titanyl sulfate. According to this method, particles having a particle size in the range of 5 to 70 mμ are generally obtained. At this time, it is preferable to perform a general chemical treatment using an oxide such as silicic acid, aluminum oxide, zinc oxide, or a hydroxide such as aluminum hydroxide or zinc hydroxide. The amount added is preferably 1 to 20% by weight based on rutile-type titanium oxide. If the amount added is too small, the rutile-type titanium oxide will deteriorate due to sunlight and the surface will darken. If the amount added is too large, the rutile-type titanium oxide will deteriorate. The UV absorption effect of titanium decreases. The rutile-type titanium oxide used in the present invention is preferably one that has been made hydrophobic with an organic compound or the like. Many known techniques have been proposed for hydrophobizing pigments, but when using an organic compound as a treatment agent, considering the safety to the skin and the absence of deterioration due to ultraviolet rays, organic compounds with a carbon number of C14 to C22 are recommended. It is preferable to perform hydrophobization treatment with higher fatty acids or salts thereof. Higher fatty acids with a carbon number of C13 or less have safety issues for the skin, and those with a carbon number of C23 or more have lower solubility during treatment, so no treatment effect is observed. Titanium oxide, especially rutile type, reacts with higher fatty acids and chemically reacts with the titanium on the surface of titanium oxide particles to form titanium fatty acid stones. It does not dissolve in acetone, benzene, toluene, ether, liquid parasol, squalane, castor oil, IPM, etc. The amount of fatty acid to be treated is preferably 0.5 to 10.0% by weight based on rutile titanium oxide. If the amount is too small, the hydrophobization effect will be poor, and if the amount is too large, unreacted fatty acids will remain, and organic solvents will Needless to say, it may also dissolve in the cosmetic base material, which may impair the stability of the cosmetic. The specific titanium oxide used in the present invention is
For example, it is manufactured as follows. The titanyl sulfate aqueous solution is hydrolyzed by heating (boiling point temperature), and after cooling, it is filtered and washed with water. Next, sodium stearate and aluminum hydroxide are added to this slurry, and the mixture is heated and kneaded. After washing, dry and crush. In addition, it is manufactured according to a conventional general method for manufacturing rutile-type titanium oxide, such as using titanium tetrachloride. The specific titanium oxide of the present invention is blended in a cosmetic base in an amount of 0.1 to 40% by weight. Next, the effects of the present invention will be explained. We synthesized titanium oxide (rutile type) with different particle sizes and investigated their hiding power and UV absorption effect. Titanium oxides with different particle sizes were synthesized by a hydrolysis method using an aqueous titanium tetrachloride solution and an aqueous titanyl sulfate solution. To measure the hiding power and ultraviolet absorption effect of the synthesized titanium oxide, make a slurry by adding 60 parts of castor oil to 40 parts of titanium oxide and kneading thoroughly using three rollers. Take 25 parts of the slurry, add 75 parts of castor oil, and use a stirrer to further disperse titanium oxide. A film with a thickness of 5 μm was made with the dispersion on a transparent quartz plate, and the film was measured at 280 μm using a Hitachi 340 spectrophotometer.
Absorbance (ABS) in the wavelength range of 400nm and 400~
Transmittance in the wavelength region of 700 nm was measured. For comparison, Japanese Patent Publication No. 47-42502 and ordinary titanium oxide were also measured in the same manner. The results of each measurement are shown in FIGS. 1 and 2. The horizontal axis in Figure 1 shows wavelength (nm), and the vertical axis shows absorbance (Adsorption).
shows. Curve a shows normal titanium oxide with an average particle size of 350 mμ, curve b shows the same titanium oxide as in Japanese Patent Publication No. 47-42502 with an average particle size of 30 to 40 mμ, and curve c shows titanium sulfate with an average particle size of 10 to 30 mμ. Curve d shows rutile-type titanium oxide synthesized from an aqueous solution, and curve d shows rutile-type titanium oxide synthesized from an aqueous titanium tetrachloride solution with an average particle size of 5 to 10 mμ. Second
The horizontal axis of the figure shows wavelength (nm), and the vertical axis shows transmittance (%). Curve a shows normal titanium oxide with an average particle size of 350 mμ, curve b shows the same titanium oxide as in Japanese Patent Publication No. 47-42502 with an average particle size of 30 to 40 mμ, and curve c shows titanium oxide with an average particle size of 10 to 40 mμ.
Curve d shows rutile-type titanium oxide synthesized from a 30 mμ titanyl sulfate aqueous solution, and curve d has an average particle size of 5 to 5.
Rutile type titanium oxide synthesized from a 10 mμ titanium tetrachloride aqueous solution is shown. As is clear from Figures 1 and 2, when the average particle diameter of titanium oxide is as large as 350 mμ, there is no effect of absorbing ultraviolet rays and the transmittance of visible light is low.
When the average particle size becomes 30 to 40 mμ, the effect of absorbing ultraviolet rays becomes visible, and the maximum absorption wavelength is
Located in the 320-340nm region. The transmittance of visible light is also considerably increased. As the average particle size becomes smaller (10 to 30 mμ), the ultraviolet absorption effect becomes more visible, and the maximum absorption wavelength is the one with the strongest biological effect.
It also has a wavelength of 290 to 320 nm. The transmittance of visible light is also very high. When the average particle diameter is reduced to 5 to 10 mμ, the transmittance of visible light increases, but the ultraviolet absorption effect weakens and the maximum absorption wavelength becomes 290 nm or less. Therefore, the average particle diameter used in the present invention is 10
It can be seen that rutile-type titanium oxide with a diameter of ~30 mμ more effectively absorbs the mid-ultraviolet (UV-B) wavelength region of 290 to 320 nm, which is said to have the strongest biological effect. If the rutile-type titanium oxide ultrafine particle pigment is blended as it is, the oil absorption amount will be very large, so it is preferable to perform a hydrophobization treatment. Also has makeup,
In other words, it must be waterproof against sweat, water, and seawater. If it does not have good dispersibility in cosmetic bases such as oils, excellent stability, and good usability, it will not be effective in absorbing ultraviolet rays, and its quality as a cosmetic will naturally deteriorate. In addition, the increased surface activity causes deterioration of the cosmetic base and blackening due to sunlight. For this reason as well, it is preferable that the ultrafine particulate titanium oxide contains 1 to 20% by weight of an inorganic oxide or inorganic hydroxide and is made hydrophobic. In other words, by containing 1 to 20% by weight of an inorganic oxide or inorganic hydroxide and making it hydrophobic, it is expected that miscibility with oil will improve, dispersibility will be good, and oil absorption will decrease. At the same time, light resistance is improved. For this reason, it is possible to increase the amount of the compound added to cosmetics, and cosmetics that do not impair the ultraviolet absorption effect can be expected. The oil absorption of ultrafine titanium oxide treated with higher fatty acids to make it hydrophobic was measured. For comparison, untreated titanium oxide and titanium oxide with different particle sizes were also measured. To measure the oil absorption amount, place 3 g of titanium oxide on a glass plate, drop refined linseed oil little by little into the center of the titanium oxide pigment from a 50 ml bottle, and mix thoroughly with a spatula each time. This operation was repeated, and the end point was when the whole became a solid putty-like lump for the first time.The amount of refined linseed oil required for this was determined, and the oil absorption was calculated from the following formula. Oil absorption amount (ml/100g) = (linseed oil amount (ml) / titanium oxide amount (g)) x 100 The results are shown in Table 1.

[Table] Rutile titanium oxide (aluminum hydroxide)
10%)
As is clear from the above results, oil absorption is significantly reduced by hydrophobicizing ultrafine titanium oxide particles with higher fatty acids. Table 2 shows the dispersibility of titanium oxide when dispersed in oil commonly used as a cosmetic base. The method for evaluating dispersion is
Titanium oxide 1 in a 50ml graduated sedimentation tube (Ukena tube)
g Weigh, add 50 ml of oil, stir and disperse using a dispersion machine (Polytron), observe the dispersion state after standing for each time, score 5 points if there are no settled particles, and all are in a settled or agglomerated state. 1 point is given to those with very good dispersion at the time of observation, 1 point is given to those with very good dispersion, and 1 point is given to those with very good dispersion at the time of observation, and 1 point is given to those with very good dispersion at the time of observation. Each item is counted as 1 point, and 10
Evaluation was performed using a stepwise method. The observation times were 1 minute, 5 minutes, 30 minutes, 1 hour, 1 day, 3 days, and 3 days after the dispersion was allowed to stand.
It was observed 7 times on the 7th day.

[Table] Rutile titanium oxide (aluminum hydroxide)
10%)
As is clear from Table 2, ultrafine particulate titanium oxide that has been hydrophobized with higher fatty acids has very good dispersibility in commonly used cosmetic base materials. O/W to investigate the dispersion state in more detail
The dispersion state of titanium oxide was investigated by adding it to a mold emulsion.
Table 3 shows the formulation of the O/W type emulsion.

[Table] To prepare the emulsion, add polyethylene glycol to purified water, heat and dissolve, then add ultrafine titanium oxide, vegum, polyoxyethylene (25 mol) monooleic acid ester, disperse uniformly with a homomixer, and heat to 70℃. Keep (aqueous phase). Mix other ingredients, heat and dissolve and keep at 70℃ (oil phase). The oil phase was added to the water phase and uniformly emulsified and dispersed using a homomixer. After emulsification, the mixture was cooled to 35°C while stirring. The state of dispersion of titanium oxide in the emulsion thus prepared was observed using an optical microscope. Figure 3 A is an average particle size of 10~
Figure 3B shows the dispersion state of an emulsion using 30 mμ of ordinary ultrafine particle rutile titanium oxide using the same ultrafine particle rutile titanium oxide containing 10% aluminum hydroxide that has been hydrophobized with 5% stearic acid. This is the dispersed state of emulsion. As is clear from Figure 3, ultrafine titanium oxide B that has been hydrophobized is very well dispersed, whereas ultrafine titanium oxide A that has not been hydrophobized is in an agglomerated state and has poor dispersion. state. It can be seen that the ultrafine particulate titanium oxide that has been hydrophobized using a higher fatty acid exhibits an excellent dispersion state in the cosmetic base material. Furthermore, stability, usability, and UV protection effects were investigated. Stability was evaluated by measuring the activity of titanium oxide with different particle sizes. The measurement method is titanium oxide 0.2
g was weighed in a glass tube, and the decomposition rate of isopropanol (3 μl) was determined by the microreactor method. Isopropanol is decomposed into propylene and acetone due to surface activity (acid sites, basic sites). Table 4 shows the results.

[Table] When the particles of titanium oxide become fine, more than 90% of isopropanol is decomposed due to surface activity.
It can be seen that the ultrafine particulate titanium oxide that has been hydrophobized with higher fatty acids has almost the same activity as normal (350 mμ) titanium oxide, and is much weaker. In addition, in order to examine the stability against light, an O/W type emulsion was prepared using the same formulation shown in Table 3, and for comparison, the same amount of fine particulate titanium oxide (average particle size 30 to 40 mμ) was prepared. Three products of sample No. C, an O/W type emulsion prepared by adding 6.0% by weight to the same formulation, were irradiated for 90 hours at 50°C using a xenon lamp.
The degree of blackening at that time was investigated. Table 5 shows the results.

[Table] *Mark: Ultrafine rutile-type titanium oxide treated with 5% stearic acid to make it hydrophobic (contains 10% aluminum hydroxide)
As shown in Table 5, after hydrophobic treatment,
Ultrafine titanium oxide containing 10% aluminum hydroxide is stable against light. Next, the usability and UV protection effect of the O/W type emulsions shown in Table 5 were investigated by actual use using a panel and instrumental measurement using a spectrophotometer. Usability of O/W type emulsion is based on female panel 20
The O/W type emulsion with names A, B, and C is actually used on the entire face, and when used, it gives a feeling of ``spreadiness,''``stickiness,'' and ``sweetness.''
Evaluation was made on five items: "whiteness" and "overall evaluation." The evaluation method was to evaluate "spreading", "tsuki", and "overall evaluation" in order of strength. "Sweet feeling"
The items were rated in order of "freshness".
Regarding "white spots", the items were evaluated in descending order of "white spots". The number of people who answered ``good'', ``satsuppari'', or ``not white'' for each evaluation item was calculated in the 6th test.
It is summarized in the table.

[Table] As can be seen from Table 6, emulsion B using hydrophobized ultrafine titanium oxide was not white and had a crisp texture even when applied, and was evaluated as a very good emulsion. Next, in order to investigate the water resistance and UV protection effect during actual use, four female panels were asked to use O/W type emulsions A, B,
Two microliters (μl) of C was applied to each square centimeter (cm ² ) on the back, and water resistance and ultraviolet protection effects tests were conducted at Yamada Beach, Onna Village, Okinawa Prefecture in midsummer (clear weather in July). In the water resistance test, two female panelists applied emulsion to their backs and swam in the ocean for 10 minutes from 10:50 a.m. to 11:00 a.m. Two panelists who swam and two panelists who applied the emulsion to their backs and did not swim were each subjected to a tanning test on the skin of the applied sample for 2 hours from 11 a.m. to 1 p.m. After being exposed to sunlight for 2 hours, the sample was dropped, and the intensity of sunburn, especially erythema, was visually determined twice, one hour later and one day later. 7th
The table is the result.

【table】

[Table] ○: Strong erythema is observed △: Weak erythema is observed ×: No erythema is observed. As is clear from Table 7, after applying the emulsion,
In the panel that swam in seawater, strong erythema was observed on the skin to which the A and C emulsions were applied, and no erythema was observed at all on the skin to which the B emulsion was applied. This means that A and C have poor water resistance and the applied emulsion is easily washed off by seawater. Compared to these, emulsion B using ultrafine titanium oxide that had been subjected to hydrophobization treatment had excellent water resistance, and the applied emulsion did not fall off even when swimming, and an excellent ultraviolet protection effect was observed. As a result of the UV protection effect on panels that do not swim in seawater, weak erythema was observed for emulsions A and C, whereas for B
Since no erythema is observed in the emulsion, the emulsion that has been hydrophobized and has excellent dispersibility has better protection against ultraviolet rays. Furthermore, the absorbance of these three types of emulsions in the ultraviolet region was measured. The measurement method was to form a film with a thickness of 5 μm on a transparent quartz plate with each emulsion A, B, and C, and measure the absorbance at a wavelength of 280 nm to 400 nm using a Hitachi Model 340 spectrophotometer. Figure 4 shows the results. As can be seen from Figure 4, the medium ultraviolet region (290~
320 nm), the absorbance of emulsion B is strong, and the absorbance of emulsion A and C is strong.
Emulsion has weak absorbance. There is a very good agreement between these measurement results and the erythema judgment results in actual use.
The higher the absorbance at 320 nm), the better the UV protection effect against sunlight. These results show that hydrophobized rutile-type ultrafine particulate titanium oxide, with an average particle diameter of 10 to 30 mμ, has a maximum absorption wavelength of 290 to 320 nm, has good dispersibility in cosmetic base materials, and has good dispersibility in the visible region of 400 to 700 nm. Because it has excellent penetrating power, it has no hiding power and has excellent protection against ultraviolet rays. This is a special public service from 1977.
-42502 "Sunscreen cosmetics" had far more effective results. Examples of the present invention are shown below. (Blending proportions are in weight%) Example 1 Emulsion Stearic acid 2.4% Cetyl alcohol 1.5〃 Vaseline 5.0〃 Liquid paraffin 12.0〃 Polyoxyethylene (10 mol) Monooleic acid ester 2.0 Polyethylene glycol 1500 3.0 Triethanolamine 1.0 Purified water 72.5 Rutile-type ultrafine particle titanium oxide containing 2% zinc oxide hydrophobized with 3% sodium myristate (average particle size 10-30mμ) 0.1 Flavor Appropriate amount Add polyethylene glycol and triethanolamine to purified water and heat to dissolve at 70℃. keep (aqueous phase),
Mix the other ingredients, heat and dissolve and keep at 70℃ (oil phase), add the oil phase to the water phase and pre-emulsify, homogeneously emulsify with a homomixer, and after emulsification, hold at 70℃ while stirring.
Cool until cool. Example 2 Foundation cream Talc 15.0% Regular titanium oxide 4.0〃 Kaolin 3.0〃 Rutile type ultrafine particle titanium oxide containing 5% silicon oxide hydrophobized with 0.5% palmitic acid (average particle size 10-30 mμ) 15.0〃 Iron oxide (red) 0.29〃〃 (yellow) 0.67〃〃 (black) 0.04〃 Solid paraffin 3.0〃 Lanolin 10.0% Liquid paraffin 27.0 Sorbitan sesquioleate 5.0 Purified water 17.0 Fragrance Appropriate amount Talc, usually titanium oxide, kaolin, hydrophobized The rutile-type ultrafine particle titanium oxide and iron oxide (red, yellow, black) are mixed and processed in a pulverizer (powder section). Add a part of liquid paraffin and sorbitan sesquioleic acid ester to the powder part and uniformly disperse with a homomixer, heat and melt the other ingredients except purified water, add to this and keep at 70°C (oil phase). purified water
Heat to 70°C, add to the oil phase, and uniformly emulsify and disperse with a homomixer. After emulsification, cool to 40°C while stirring. Example 3 Foundation Stick Kaolin 10.0% Mica powder 21.0〃 Normal titanium oxide 4.58〃 Iron oxide (red) 0.34〃〃 (yellow) 1.08〃 Aluminum oxide hydrophobized with 4% behenic acid
Rutile-type ultrafine titanium oxide containing 10% (average particle size 10 to 30 mμ) 20.0% Solid paraffin 2.0〃 Carnauba wax 3.0〃 Squalane 31.0〃 Isopropyl myristate 5.0〃 Sorbitan sesquioleate ester 2.0〃 Fragrance Appropriate amount Kaolin, mica powder , usually titanium oxide, iron oxide,
The hydrophobized rutile-type ultrafine particulate titanium oxide is thoroughly mixed with a blender (powder part). A portion of squalane and sorbitan sesquioleic acid ester are added to the powder part and uniformly dispersed using a homomixer, and the other components are heated and melted, and then added to this and stirred well. Pour this into a container and cool it. Example 4 Rutile-type ultrafine particle titanium oxide (average particle size) containing 20% silicon oxide hydrophobized with 5% sodium stearate and 2% sodium palmitate
10~30mμ) 5.0% Red No. 204 0.6% Orange No. 203 1.0〃 Red No. 223 0.2〃 Candelilla wax 9.0〃 Solid paraffin 8.0〃 Beeswax 5.0〃 Carnauba wax 5.0〃 Lanolin 11.0〃 Castor oil 44.8〃 Isopropyl myristate ester 10.0 Fragrance Appropriate amount Hydrophobic rutile-type ultrafine particle titanium oxide,
Add red No. 204 and orange No. 203 to some of the castor oil and process with a roller (pigment section). Dissolve Red No. 223 in a portion of castor oil (dye part). After mixing the other ingredients and heating and melting, add the pigment part and dye part and uniformly disperse with a homomixer. After dispersion, it is poured into a mold and rapidly cooled, and the stick-like material is inserted into a container for framing. Example 5 Solid white powder Talc 45.0% Rutile-type ultrafine particles containing 8% aluminum hydroxide hydrophobized with 10% stearic acid and 5% silicon oxide Titanium oxide (average particle size 10 to 30 mμ) 40.0% Regular titanium oxide 3.0〃 Iron oxide red 1.00〃 Iron oxide yellow 2.88〃 Iron oxide black 0.12〃 Stearic acid 2.0〃 Squalane 2.5〃 Lanolin 2.0〃 Sorbitan sesquioleate 0.5〃 Triethanolamine 1.0〃 Fragrance Appropriate amount Talc, hydrophobized rutile type ultrafine particles While titanium oxide, usually titanium oxide, and iron oxide are thoroughly mixed in a blender, a mixture of other ingredients is added uniformly to this mixture, processed in a pulverizer, and compression molded.

[Brief explanation of drawings]

Figure 1 shows castor oil, which is a base material for cosmetics, a (average particle diameter 350 mμ), b (average particle diameter 30-40 mμ), and c (average particle diameter 10-40 mμ).
30 mμ) and d (5 to 10 mμ) of titanium oxide dispersed therein.
Figure 2 shows a (average particle size of 350 mμ), b (30-40 mμ), and c (10-40 mμ) of castor oil, which is a base material for cosmetics.
The transmittance in the visible light region is shown when titanium oxide of 30 mμ) and d (5 to 10 mμ) is dispersed. Figure 3 shows rutile-type ultrafine particle titanium oxide with an average particle size of 10 to 30 mμ (A) untreated, (B) 5% stearic acid.
An optical micrograph showing the particle structure at 600 times magnification is shown when the hydrophobized product (containing 10% aluminum hydroxide) is blended into an O/W type emulsion. Figure 4 shows O/W type emulsion with A (average particle size 10~
30 mμ), B (average particle size 10 ~ hydrophobized with 5% stearic acid and containing 10% aluminum hydroxide)
30 mμ) and C (average particle diameter 30 to 40 mμ) in the case of blending titanium oxide in the ultraviolet wavelength region.

Claims (1)

[Claims] 1 Containing 1 to 20% by weight of inorganic oxide or inorganic hydroxide, and hydrophobized average particle size of 10 to 20% by weight
A cosmetic containing 0.1 to 40% by weight of 30mμ rutile titanium oxide.