JPH01301517A - Production of titanium dioxide-cerium oxide multiple sol and cosmetic blended with same - Google Patents

Abstract

PURPOSE:To obtain the title multiple sol, excellent in dispersibility in dispersion media, long-term stability, ultraviolet-shielding ability etc., suitable for e.g. cosmetics, by adding hydrogen peroxide to a dispersion containing hydrated titanium dioxide and hydrated cerium oxide to make a solution followed by heating. CONSTITUTION:A hydrated titanium dioxide gel formed by neutralization hydrolysis of an aqueous solution of titanate such as titanium chloride and a hydrated cerium oxide gel formed by neutralization hydrolysis of an aqueous solution of cerium salt such as cerium nitrate are mixed with each other to prepare, e.g. by deflocculation, a dispersion containing hydrated titanium dioxide and hydrated cerium oxide. Thence, this dispersion is spiked with hydrogen peroxide and heated at pref. >=50 deg.C to dissolve said hydrated titanium dioxide and hydrated cerium oxide. The resultant solution is then heated to ca. >=60 deg.C to effect hydrolysis, thus obtaining the objective multiple sol.

Description

[Detailed Description of the Invention] The present invention relates to a titanium oxide/cerium oxide composite sol that has excellent dispersibility in a dispersion medium, long-term stability, light resistance, etc., and a method for producing the same. The present invention relates to a cosmetic containing the above-mentioned composite sol and having an excellent ultraviolet shielding effect.

No. 11: 'Jt<-Jt and No. 111: Titanium oxide is used as a compounding agent or surface coating agent for plastics etc. by taking advantage of its ultraviolet shielding power or high refractive index, or is blended into cosmetic U base materials. It is used in the production of cosmetics that have an ultraviolet shielding effect.

The titanium oxide used in these applications is preferably in the form of ultrafine particles, and in particular colloidal titanium oxide (titanium oxide sol) is preferred from the viewpoint of dispersibility in media and stability. As a titanium sol, the present inventors proposed a titanium oxide sol having various characteristics not found in conventional titanium oxide sols in ``Titanium oxide sol and its manufacturing method'' (Japanese Patent Application No. 252953/1982).

By the way, titanium oxide fine particles that are added to cosmetics to provide an ultraviolet shielding effect are generally in the form of powder. However, the conventionally known titanium oxide powder is
Cosmetic *1 It was difficult to uniformly disperse it in the base material, and as a result, the UV shielding effect was poor. Furthermore, when titanium oxide powder as described above is blended into a lotion, there are problems with dispersibility and stability, such as particles gradually settling.

In order to solve these problems, the present applicant proposed a cosmetic composition containing fine particles of a composite of titanium oxide, silicon oxide, and/or zirconium oxide, in Japanese Patent Application No. 62-17.
It was proposed in No. 2293.

However, titanium oxide-based composite fine particles such as those described above are not suitable for ultraviolet rays in the wavelength range of 280 to 320 nm (UV-8
It shows an excellent shielding effect against ultraviolet rays in the 3
There was a problem in that it did not show a sufficient shielding effect against ultraviolet rays in the wavelength range of 20 to 400 nl, especially 340 to 380 nl (UV-A region).

The present invention aims to solve the above-mentioned problems with titanium oxide sol, and uses a titanium oxide/cerium oxide composite that has excellent shielding ability against ultraviolet rays in the UV-A region. The object of the present invention is to provide a method for producing a composite sol and a cosmetic containing the composite sol and having an excellent ultraviolet shielding effect.

The titanium oxide/cerium oxide composite sol according to the present invention is
The method is characterized in that hydrogen peroxide is added to a dispersion of hydrated titanium oxide and hydrated cerium oxide to dissolve the hydrated titanium oxide and hydrated cerium oxide, and then the resulting solution is heated.

Furthermore, the cosmetic according to the present invention is characterized in that it contains titanium oxide/cerium oxide composite fine particles obtained as described above.

■ It O < 2 A method for producing a titanium oxide/cerium oxide composite sol according to the Japanese invention will be described.

First, in the present invention, a mixed gel or sol of hydrated titanium oxide and hydrated cerium oxide, or a co-precipitation gel or sol of both is prepared.

The mixed gel of hydrated titanium oxide and hydrated cerium oxide is
For example, hydrated titanium oxide gel obtained by neutralizing and hydrolyzing an aqueous solution of titanium salts such as titanium chloride and titanyl sulfate;
It is obtained by mixing it with a hydrated cerium oxide gel obtained by neutralizing and hydrolyzing a cerium salt such as cerium nitrate. Alternatively, a hydrated titanium oxide gel or a hydrated cerium oxide gel may be prepared in advance, and a cerium salt aqueous solution or a titanium salt aqueous solution may be added thereto for neutralization and hydrolysis to obtain a mixed gel.

Further, the mixed sol can be obtained by peptizing the mixed gel prepared by the method described above with an acid such as nitric acid or hydrochloric acid.

A coprecipitated gel of hydrated titanium oxide and hydrated cerium oxide is obtained by neutralizing and hydrolyzing a mixed aqueous solution of a titanium salt and a cerium salt. Furthermore, a sol can be obtained by peptizing this coprecipitated gel with acid. These mixed gels or sol,
Alternatively, coprecipitation gel or sol is not limited to the above method,
It can be prepared by a conventionally known method. In this specification, "hydrated titanium oxide" and "hydrated cerium oxide" are general terms including titanium oxide, hydrates of cerium oxide, titanium hydroxide, and cerium hydroxide.

The ratio of titanium oxide and cerium oxide in the gel or sol obtained by these methods is determined by the ratio of CaO,
, /TiO□ (f! amount ratio) is preferably adjusted to at least 0.1.

If CeO/TlO2 (weight ratio) is less than 0.1, the effect of adding cerium oxide will not be effectively expressed, which is not preferable.

In addition, when the proportion of cerium oxide increases, it becomes difficult to dissolve the next culm with hydrogen peroxide, so Ce O,, /
Preferably, Ti 02 (weight ratio) is about 20 or less.

Next, hydrogen peroxide is added to the gel and/or sol obtained by the above method to dissolve hydrated titanium oxide and hydrated cerium oxide to prepare a homogeneous aqueous solution. At this time, the amount of hydrogen peroxide added, which is preferably heated to 50°C or higher, is H20□/(TiO2+COO□
) (weight ratio) of 1 or more, hydrated titanium oxide and hydrated cerium oxide can be completely dissolved. I
(2) If 202/(T + 0 + Ce O2) is less than 1, it is not preferable because hydrated titanium oxide and hydrated cerium oxide are not completely dissolved and remain. Also, ■f20□/
When the weight ratio of (Ti 2 O, 10Ce O2) is large, the solubility of hydrated titanium oxide and hydrated cerium oxide is high, and the reaction is completed in a short time. However, if too much hydrogen peroxide is used, a large amount of unreacted hydrogen peroxide remains in the system, which is not economical and does not affect the next step, which is not preferable. Therefore, HO/(Ti02+Ce02
It is desirable that the weight ratio of It will completely dissolve in about 0.5 to 8 hours depending on the amount.

If the concentrations of hydrated titanium oxide and hydrated cerium oxide are not high, it will take a long time to dissolve them, undissolved substances will precipitate, and the resulting aqueous solution will become too viscous. Therefore,
It is desirable that the concentration in the aqueous solution after dissolution is about 10 Saturn% or less, preferably about 5ffii% or less as (Ti 2 O + Ce O 2 ).

Next, this aqueous solution can be used as is or (TiO□
+CQ 02): After adjusting the a degree by adding water to the aqueous solution, etc., hydrolyze by heating to 60° C. or higher, preferably 80° C. or higher. In this way, a titanium oxide/cerium oxide composite sol in which composite particles of titanium oxide and cerium oxide are dispersed is obtained.

What is the titanium oxide/cerium oxide composite sol mentioned here?
A mixed sol of titanium oxide particles and cerium oxide particles, a sol in which composite oxide particles in which titanium oxide and cerium oxide are chemically bonded, or a single particle in which titanium oxide and cerium oxide are physically bonded are used. It means a dispersed sol or a mixed sol.

The sol obtained by the above method has a particle size of about 4 to 300 mμ.
It is a stable sol with excellent light resistance, in which fine particles with an average particle size of A sol can also be produced by heating and hydrolyzing in the presence of a compound. That is, Zn
Group III of the periodic table such as A, G, etc., Ti,
Group Ⅰ such as Zr, s;, sn, etc., Group V of Sb5,
After mixing the above aqueous solution with an inorganic compound of one or more elements selected from Group V1 such as W and Group II such as Fe, the resulting mixture is heated to 60'C or higher. Hydrolyze.

The above-mentioned inorganic compounds are used in the form of salts, oxides, hydroxides, oxyacids, oxyacids, and the like. These inorganic compounds may be used in solid form or as an aqueous solution, but it is preferable to use them in the form of a gel or sol.

When the inorganic compound is used in the form of a sol, it is desirable that the average particle size of the dispersed particles is about 30 mμ or less, preferably about 15 mμ or less; for example, in the case of silicon,
Alkali silicates, silica gels, silica sol or silica formulations are used.

Here, the Geic acid solution refers to a low polymer solution of silicic acid obtained by dealkalizing an aqueous alkali silicate solution using an ion exchange method or the like.

By increasing the amount of inorganic compounds in the mixture, the long-term stability and light resistance of the resulting sol improves, and a highly concentrated sol can be obtained. However, after these effects reach a predetermined level, even if the amount of g(1) compound is increased, the long-term stability,
This is undesirable because no increase in the effect of improving light resistance etc. can be seen, but on the other hand, if the amount of the inorganic compound mixed is reduced,! !
This is not preferable because the effect of mixing the machine and machine parts is not expressed.

Considering the above, the amount of inorganic compounds to be mixed is determined by adding hydrogen peroxide to a dispersion of hydrated titanium oxide and hydrated cerium oxide to dissolve the hydrated titanium oxide and hydrated cerium oxide. Titanium and cerium in the resulting aqueous solution (hereinafter referred to as hydrogen peroxide dissolved aqueous solution) were
The ratio of the value converted to O2 + Cc02) and the value converted to oxide (MO) of the weight of inorganic compounds ('T'' i 02
+xC002)7MOx (weight ratio) or preferably in the range of 0.25 to 200.

There are no particular restrictions on the method of mixing the aqueous solution of hydrogen peroxide and the inorganic compound, and a predetermined amount of the aqueous solution of hydrogen peroxide and the inorganic compound are mixed together. It is also possible to mix the aqueous hydrogen peroxide solution and a portion of the inorganic compound at first, heat the mixture, and then add the rest of the two as the reaction progresses. Furthermore, it is also possible to first mix and heat all of the inorganic compounds and a portion of the hydrogen peroxide-dissolved aqueous solution, and then add the remaining aqueous solution.

In addition, the timing of mixing the dual function compound does not necessarily have to be after the hydrated titanium oxide and hydrated cerium oxide have been dissolved in hydrogen peroxide, but can be mixed at the gel or sol stage before being dissolved in the hydrogen peroxide. It is also possible to mix hydrated titanium oxide and cerium peroxide when preparing a gel or sol.In short, when the aqueous solution dissolved in hydrogen peroxide is heated and hydrolyzed, the above-mentioned inorganic compounds It is sufficient if it exists in the reaction system.

The titanium oxide/cerium oxide composite sol thus obtained has particles with an average particle size of 4 to 300 mμ dispersed in an aqueous dispersion medium, and has excellent dispersibility, long-term stability, and light resistance.
Moreover, it is a stable sol in a wide pH range (3 to 12).

The titanium oxide/cerium oxide composite sol obtained by the production method of the present invention can be used as is for various purposes, but it can be concentrated to an appropriate concentration using known methods such as vacuum evaporation and ultrafiltration. It can also be used as Further, depending on the application, it can be mixed with or substituted with an organic solvent such as alcohol or glycol to form an organic solvent-dispersed sol.

Next, the cosmetics according to the present invention and the method for producing the same will be described. In the present invention, after adjusting the concentration of the titanium oxide/cerium oxide composite fine particles in the composite sol obtained as described above, Cosmetics can be obtained by mixing the sol with other cosmetic base materials in a well-known manner. As can be seen from the production method described in E+i, the Nh-based sol F in the present invention has a PTT of 3 or more, usually 5 to 9, so it can be incorporated into cosmetics as is.

Furthermore, even if the titanium oxide/cerium oxide composite sol of the present invention using water as a dispersion medium is mixed with an organic solvent such as alcohol, glycol, or glycerin, or even if the solvent is replaced, the composite sol will not be affected by surfactants, etc. It is very stable even without the addition of Therefore, depending on the type of cosmetic, the composite sol according to the present invention can be blended into the cosmetic as an organic sol using the above-mentioned organic solvent as a dispersion medium.

In the cosmetic according to the present invention, the titanium oxide/cerium oxide composite sol has (Ce02+T+02) based on the total weight of the cosmetic, although it varies depending on the type of cosmetic.
as, at least 0.001% by weight, preferably 0.001% by weight.
005 to 90% by weight. If the amount of the composite sol is less than 0.001% by weight, the resulting cosmetic will not have a sufficient ultraviolet shielding effect, which is not preferable.

The cosmetics according to the present invention can be in the form of powder, cake, pencil, snack, cartilage, liquid, etc., and specifically include lotions, foundations, creams, milky lotions, eye shadows, and makeup bases. , nail enamel, eyeliner, mascara, lipstick, pack, shampoo, conditioner, hair cosmetics, etc.

] The titanium oxide/cerium oxide composite sol according to the present invention is
Extremely stable over a wide pH range of 3 to 12, 4 to 300 m
This is a sol in which FR particles with a particle size of μ are uniformly dispersed, and has excellent dispersibility, long-term stability, and light resistance. Furthermore, since it contains cerium oxide, it has a greater shielding effect against ultraviolet rays in the fI range of 320 to 400 nl, especially 340 to 380 nl, compared to titanium oxide sol of the same concentration.

The titanium oxide/cerium oxide composite sol according to the present invention is
Various uses can be considered by utilizing the above characteristics.

If you mix a water-dispersed sol with an organic solvent or replace the solvent to make an organic solvent-dispersed sol and use it as a compounding agent for plastics and paints, it can be used to prevent deterioration of plastics due to ultraviolet rays and discoloration of pigments in paints. You can expect good results. Furthermore, if it is incorporated into a glass film for food packaging, it can be stored for a longer period of time compared to conventional packaging materials. Plastic materials for contact lenses (for example, H
When dispersed in EM^), it becomes a contact lens that protects the retina from ultraviolet rays.

Further, by applying a coating solution prepared by mixing and dispersing the organic solvent-dispersed sol in a coating solution for forming a transparent film onto glass and applying a transparent thin film to the glass surface, an ultraviolet-shielding glass can be obtained. In addition, the high refractive index of titanium oxide and cerium oxide in the composite sol according to the present invention can be applied to plastic lenses to produce high refractive index lenses.

Furthermore, the cosmetic makeup 1 of the present invention has an excellent ultraviolet shielding effect,
In particular, it is easy to cause melanin pigmentation on the skin340
～38 Or+n (UV-A area LAi) Always blocks ultraviolet rays of 41% well, provides excellent protection of skin from ultraviolet rays, and has excellent dispersibility even when added to cosmetic base materials in large quantities. In addition, the makeup T1 is 11 (excellent in luminosity, feel of use, and finish. Also, the average particle size is about 80
Cosmetics containing titanium oxide/cerium oxide composite fine particles with a particle size of less than mμ do not lose their transparency even when added in relatively large amounts, so they are suitable as cosmetic formulations that require transparency. There is.

EXAMPLES The present invention will be explained below with reference to Examples, but the present invention is not limited to these Examples.

5g of cerium chloride as K1 type CeO and 5g as TiO2
and titanium tetrachloride were dissolved in pure water to prepare 1000 g of a mixed aqueous solution. 15% ammonia water was gradually added to this until the pH reached 9.0, to obtain a coprecipitated gel of hydrated titanium oxide and hydrated cerium oxide.

After dehydrating and washing the coprecipitated gel thus obtained, 115 g of 35% hydrogen peroxide and 25 g of pure water were added to 110 g of the coprecipitated gel, and then heated to 80°C.
250 g of a transparent aqueous solution of hydrogen peroxide in a pale yellow-orange-brown color was obtained. The l]H of this aqueous hydrogen peroxide solution was 8.7. After diluting this aqueous solution with pure water to 0.1% by weight as oxide (TiO+CO02),
Heated at 5°C for 96 hours. After 96 hours, a transparent titanium oxide/cerium oxide composite sol was obtained which was pale yellow and milky white.

The pH of this sol is 6.8, with a minimum of 6 mμ and a maximum of 20
mμ fine particles are dispersed, and the specific surface area of these fine particles (
B E "I' method) was 256rd/lt. Also, this sol was evaporated by vacuum evaporation method (Ce O2T i O2)
It was stable even when layered (up to 20% gravity).

In addition, a part of the sol obtained above was converted into an oxide ('I' +
0 CQ 02 ) and diluted to a concentration of °ζ 0.05% by weight, placed in a 1-city thick quartz cell, and measured with a spectrophotometer (Hitachi vJ330 model) at 260 to 500 nm.
The light transmittance of m was measured.

The results are shown in FIG. 1 (curve A).

Hydrogen peroxide-dissolved aqueous solution M obtained in the same manner as Hihara-riyu Example 1
At 250K, average particle size 7 mμ, 5102 concentration 10% by weight
After mixing 15 g of silica sol and 9.7 kg of pure water, the mixture was heated at 150° C. for 10 hours. After 10 hours, a transparent titanium oxide/cerium oxide composite sol was obtained which was pale yellow and milky white. The pH of this sol is 7.3, the dispersed particle diameter is 7 to 21 mμ, and the specific surface area of the particles is 266rtf'
/g. This sol was prepared in the same manner as in Example 1.
It was stable even when concentrated to a heavy concentration. Furthermore, the light transmittance obtained by training in the same manner as in Example 1 was almost the same as that in Example 1.

Aim for shaku! As CeO2, 10 g of ceric ammonium oxide was dissolved in pure water to obtain a 0.5% by weight aqueous solution as CeO2. Add 15% ammonia water to this until the pH is 9.
．． After gradually adding the solution until it reached 0, it was dehydrated and washed, yielding 100 g of hydrated cerium oxide gel. 112 g of 5% by weight hydrochloric acid was added to this to dissolve the hydrated cerium oxide.

Next, titanium tetrachloride water ffi solution was added to this aqueous solution so that C(! O/Ti 02 = 1 (weight/weight)), and then 15% ammonia water was gradually added to adjust the pH to 8.0.
Adjusted to. When the mixed gel of hydrated titanium oxide and hydrated cerium oxide thus obtained was dissolved in hydrogen peroxide in the same manner as in Example 1, a pale yellow-orange-brown transparent gel with ρII of 9.2 was obtained. 500 g of hydrogen oxide dissolved water/8 liquid was obtained.

Next, 500 g of this hydrogen peroxide dissolved aqueous solution was mixed with 780 g of a silicic acid solution (Si0 5% by weight) obtained by dealkalizing a water glass aqueous solution with a cationic resin and 720 g of pure water, and then heated to 172°C. . When heated for 16 hours, a titanium oxide/cerium oxide composite sol was obtained which was pale yellow and milky white and had a DH of 7.5. The diameter of the dispersed particles in this sol was in the range of 7 to 19 mμ, and the specific surface area of the particles was 243 rrf/g.

In addition, after uniformly mixing 20 g of the sol concentrated to 25% by weight of (Ce O2 + Ti 02) and 5 g of Carboball in 75 g of pure water, the mixture was spread onto a quartz plate with a doctor blade to a thickness of 5 μm. A film was prepared, and the light transmittance was measured using a spectrophotometer (Model 330, manufactured by Hitachi, Ltd.).

The results are shown in Figure 2 (Song & IA).

In Example 3, CG O2/Ti 02=1 (heavy n
The same procedure as Example 3 was carried out except that /weight ff1) was set to 4, and I)H was 6.8 and the dispersed particle size was 6 to 40.
mμ and a particle specific surface area of 350rrl'/g was obtained. Moreover, this sol was stable even when concentrated to 30 weight.

The light transmittance of the sol measured in the same manner as in Example 3 was
It is shown in the figure (curve B).

X1 and j As CeO2, dissolve 10g of ceric ammonium nitrate in pure water to make a 2.0% by weight aqueous solution as CeO2, and gradually add 15% ammonia water to this until the pH becomes 9.0. After that, it was dehydrated and then washed to obtain 118 g of hydrated cerium oxide gel. To this was added 130 g of 5% by weight hydrochloric acid to decompose the hydrated cerium oxide. Next, CeO2/Ti was added to this aqueous solution.
After adding an aqueous titanium tetraimide solution so that 02=1/9 (weight/weight), 5% ammonia water was gradually added to adjust llI to 8.4. When the mixed gel of hydrated titanium oxide and hydrated cerium oxide thus obtained was dissolved in hydrogen peroxide in the same manner as in Example 1, D
H is 9.2 and pale yellow 'lf! 250 g of a brown clear aqueous solution were obtained.

Next, in the same manner as in Example 2, a titanium oxide/cerium oxide composite sol having a pH of 7.8 was obtained.

The particle size of the dispersed particles was 4 to 25 mμ, and the specific surface area of the particles was 180//.

1 spotty ball CeO2/TiO2 9.510.5 (weight/weight)
The procedure was the same as in Example 5, except that plT was 6.5.
A titanium oxide/cerium oxide composite sol was obtained. (
Dispersed particle diameter = 4 to 65 mμ, particle specific surface area 170nf/
g).

K1 and l The titanium oxide/cerium oxide composite sol obtained in Example 4 was blended with the following ingredients in the following manner to produce a lotion.

Cerium oxide titanium oxide composite sol (CeO+TiO=30 fit%)
20% by weight propylene glycol
4,0 71 Oleyl alcohol 0.
1/J polyoxyethylene lauryl ether 0.5 j7 Ethanol 11.5% incense 11 Mi no.
0.1 Horn pure water
The cerium oxide titanium oxide composite sol obtained as described above and propylene glycol were mixed with 63.8" dyestuff pure water. Separately, a mixed solution of ethanol, oleyl alcohol, polyoxyethylene lauryl ether, and fragrance was mixed. After adjusting the mixture, the pure water mixture was added thereto.The dye was added to adjust the color, and the mixture was filtered to obtain a product.

Take a portion of this lotion and put it in a 1-thick quartz cell,
Light transmittance from the visible region to the ultraviolet region was measured using a spectrophotometer.

The results are shown in Figure 3 (curve A).

In addition, in order to evaluate light resistance, this lotion was sealed in a quartz cell, and the degree of discoloration of the lotion after being left in sunlight for 40 mouths was observed. Similarly, the degree of discoloration was examined after irradiation with carbon arc light for 300 hours and after irradiation with xenon lamp for 300 hours.

The results are shown in Table 1.

1 plate 1 A milky lotion foundation was prepared by blending the titanium oxide/cerium oxide composite sol obtained in Example 6 with the following ingredients in the following manner.

Cerium oxide titanium oxide composite sol (CaO+TiO=20% by weight) 40
Heavy, mu L% pure water
28.1 utriethanolamine
1.1 Methyl roseoxybenzoate
Appropriate amount of carboxymethyl cellulose 0.2
Weight% bentonite Q, 5
u Stearic acid 2.4 Propylene glycol horn monostearate 2, Ort Cetostearyl alcohol 0,2〃Liquid paraffin 3. O Liquid lanolin
2.0-rr isopropyl myristate g, 5 n titanium oxide pigment
1.0 n tarri
11.0% by weight fragrance
After dispersing the cerium oxide/titanium oxide composite sol in pure water, carboxymethylcellulose was dispersed therein. Bentonite was added to this, and the mixture was heated to 70° C. with thorough stirring to cause the bentonite to swell well.

Next, triethanolamine and methyl p-oxybenzoate were added to this solution. A mixed pulverized mixture of pigment and talc was added to this, well dispersed with a colloid mill, and heated to 75°C.

Separately, a mixture of stearic acid, propylene glycol monostearate, cetostearyl alcohol, liquid paraffin, and isopropyl myristate is prepared, heated to 80°C, mixed with the dispersion mixture described in art, and thoroughly stirred.

Thereafter, the mixture was cooled, a fragrance was added at 45° C., and the mixture was stirred and cooled to room temperature.

The thus obtained foundation had an excellent effect of blocking ultraviolet rays including the UV-A region, and was also excellent in feel upon use.

Titanium sulfate was dissolved in pure water to obtain an aqueous solution containing 0.4% by weight of TiO□. While stirring this aqueous solution,
15% ammonia water was gradually added to obtain a white slurry liquid of EIH8.5. This slurry was filtered and washed to obtain a cake of hydrated titanium oxide gel having a solid content concentration of 9% by weight.

To this cake 550sr, 33% hydrogen peroxide solution 610g
and 1300 g of pure water and heated at 80°C for 5 hours to form a solution 2.5% of 2.0% by weight as T i O2.
I got it. This aqueous solution is yellowish brown and transparent, and I)H is 8.1
Met.

Next, 13 g of silica sol with a particle size of 7 mμ and a concentration of 15 ml, 900 g of the above aqueous solution, and 10 g of pure water were added.
00g and then heated at 95°C for 624 hours. The solution was initially a yellow-brown liquid, but after 624 hours, a milky-white and transparent titanium oxide sol was obtained. The average particle size of the dispersed particles in this sol was 24 mμ.

A part of the obtained titanium oxide sol was diluted with pure water and Ti
The light transmittance was measured in the same manner as in Example 1, with the O2a degree being 0.05% by weight.

The results are shown in Figure 1 (curve B).

As is clear from the comparison of curves A and B, the titanium oxide/cerium oxide composite sol of the present invention is more effective in shielding ultraviolet rays, especially in the UV-A region, than titanium oxide sol that does not contain cerium oxide. I understand.

The procedure was the same as in Example 7 except that the titanium oxide sol (TiO: 30% by weight) of Example 1 was used instead of the titanium oxide/cerium oxide composite sol of Example 7. A lotion was produced using the method. The light transmittance of this lotion is shown in FIG. 3 (curve B).

Furthermore, the light resistance was evaluated in the same manner as in Example 7, and the results are shown in Table 1.

As can be seen from FIG. 3 and Table 1, the lotion of the present invention is superior to the lotion containing titanium oxide sol in the ultraviolet shielding effect including the UV-A region and the light resistance.

Request 1

[Brief explanation of the drawing]

In FIG. 1, curve A is a curve showing the light transmittance of the titanium oxide/cerium oxide composite sol according to the present invention, and curve B is a curve showing the light transmittance of the titanium oxide sol. . In FIG. 2, curve A is CeO/T according to the present invention.
This is a curve showing the light transmittance of a titanium oxide/cerium oxide composite sol with i O2 = 1 (weight/weight), and curve B
Similarly, titanium oxide with Ce O/'I"i 02=4
This is a curve showing the light transmittance of a cerium oxide composite sol. In FIG. 3, curve A is a curve showing the light transmittance of a lotion containing the titanium oxide/cerium oxide composite sol according to the present invention, and curve B is a curve showing the light transmittance of a lotion containing the titanium oxide sol. This is a curve showing the rate. Agent Patent Attorney Shunichi Suzuki 1st Wavelength (nm)

Claims (1)

[Claims] 1) Hydrogen peroxide is added to a dispersion of hydrated titanium oxide and hydrated cerium oxide to dissolve the hydrated titanium oxide and hydrated cerium oxide, and then the resulting solution is heated. A method for producing a titanium oxide/cerium oxide composite sol characterized by the following. 2) Hydrogen peroxide is added to a dispersion of hydrated titanium oxide and hydrated cerium oxide to dissolve the hydrated titanium oxide and hydrated cerium oxide, and then the resulting solution is added to a dispersion of hydrated titanium oxide and hydrated cerium oxide,
Titanium oxide characterized by heating in the coexistence of an inorganic compound of one or more elements selected from Group I, Group III, Group IV, Group V, Group VI and Group VII.・Method for producing cerium oxide composite sol. 3) A titanium oxide/cerium oxide composite sol produced by the method according to claim 1 or 2. 4) A cosmetic characterized by containing titanium oxide/cerium oxide composite fine particles. 5) A method for producing a cosmetic, which comprises blending the titanium oxide/cerium oxide composite sol produced by the method according to claim 1 or 2 into a cosmetic base material.