DE1128603B - Sunscreens that absorb ultraviolet rays - Google Patents

Description

Sunscreens that absorb ultraviolet rays are nice numerous ultraviolet absorbing compounds have become known, which are known as Light protection means are suitable and in particular organic substances or consisting of them Protect materials against the harmful effects of ultraviolet rays. However, these known light stabilizers could not meet all requirements, which result from the large number of different areas of application.

In the German patent specification 762 869 there are already phenylbutadiene derivatives has been described as a light stabilizer. The properties of the compounds mentioned there however, do not meet the practical requirements.

It has now been found that special derivatives of 1-phenyibutadiene (1,3) of the general formula can be used as light stabilizers are suitable, - in which X = COOH, COO alkyl, COalkyl, CONHAlkyl, CON (alkyl) z or CN, Y = phenyl, COOH, COO alkyl or CO alkyl can be. Furthermore, the hydrogen atoms of the phenyl radicals or the alkyl radicals can be replaced by substituents which do not have a chromophoric character, for example halogen, hydroxyl, sulfo or carboxyl groups. The term “alkyl radical” is to be understood as meaning not only aliphatic but also cycloaliphatic alkyl radicals, in particular those with 1 to 20 carbon atoms. Furthermore, esters and metal or amine salts can also be used instead of the free carboxylic or sulfonic acids.

The light stabilizers according to the invention absorb the UV light, as the curves in Figs. 1 to 4 show, in aqueous as in organic solvents with very high intensity and very favorable selectivity. The visible light will practically let through, so that the connections are mostly colorless, while the UV light is absorbed up to the limit of visible light. Important is, that the absorbed light is not converted into visible fluorescent light, as is the case with many compounds that absorb in the range of longer UV light waves, is the case, and that the substances are sufficiently stable and when exposed to light do not turn into colored compounds. The materials in which these sunscreens are used are stored, such as B. films or lacquers, remain even after prolonged exposure clear and colorless. The mentioned class of compounds includes light stabilizers for diverse areas of application. Physical ones that are important for the respective connection Properties - so z. B. the melting point and the solubility are determined by the nature of the substituents or the nature of the radicals X and Y. Compounds containing sulfo- or containing carboxyl groups are either themselves or in the form of their alkali or Amine salts soluble in water. They are therefore particularly suitable for the production of Protective coatings with the help of hydrophilic layer images. You can z. B. aqueous Add solutions of gelatine or polyacrylamide which, when dry, make clear, transparent, form the UV light absorbing films. You can by such a coating or also by impregnating the most diverse materials from aqueous solutions Protect exposure to UV light.

Compounds in which X is - COO alkyl or CO alkyl or CO NH alkyl or CON (alkyl) 2 or --CN and in which Y is phenyl, CO alkyl or COO alkyl are soluble in a wide variety of organic solvents. In addition, depending on the choice of the alkyl radical, compounds with a high melting point and those which are liquid at normal temperature can be obtained. They are particularly suitable for the production of organic protective lacquers or, for example, for incorporation in foils or fiber material made from organic high-molecular compounds. They protect such colored materials from fading in light and prevent the materials from becoming brittle. Furthermore, colorless and transparent films that absorb UV light can be produced, which are suitable as light protection curtains in front of shop window decorations or other exhibits or as protective films for image material. With the help of the water-soluble and also the organically soluble compounds from the claimed body class can -sich produce packaging materials that the packaged items, such. B. food, against the action of light and thus against spoilage, z. B. by becoming rancid protect. With regard to this field of use, it is important that the body class claimed contains numerous representatives which are without harmful effects for the human organism. For the same reason, these light protection agents are particularly suitable for the production of pastes, ointments or oils to protect the skin against sunburn.

The compounds mentioned can also be used in the photographic sector can be used with success, e.g. B. for the production of UV filters that are used in the photographic recording can be switched in front of the lens, or for production of UV filter layers in the photographic material itself. One can do this for this purpose dissolve the water-soluble representatives in layers of gelatin, or they cannot Finely disperse the water-soluble in the layer colloid. Color photographic materials can be improved in their light resistance with the help of the claimed compounds will. You can finish the dyeing baths by coating them with protective varnishes, which contain the claimed compounds, protect against exposure to light, or one after processing in aqueous solutions of the claimed light stabilizers bathe. Color images obtained with the help of chromogenic development can also thereby can be improved in light resistance that one in the photographic layers the water-insoluble light protection compounds claimed at the same time as the color components embedded and finely dispersed. After color development are the image dyes Better protected against the effects of light than with the previously known methods component storage is the case.

The areas of application mentioned here do not cover all possibilities for the use of the claimed connections. It's just meant to be expressed how versatile their possible uses are.

In the table are a number of the compounds according to the invention and their most important physical properties.

The compounds claimed can be prepared by known processes. For example, cinnamaldehyde or cinnamaldehydes substituted in the phenyl nucleus can be condensed in a known manner with malonic acid or its esters. The condensation products of the cinnamaldehydes with malonic acid can also be esterified by known methods with a wide variety of alcohols. Phenylacetic acid or cyanoacetic acid and their esters can be used in place of malonic acid or its esters. The cinnamaldehydes can also be condensed with alkylbenzyl ketones. Production: Beilstein, Handbook of Organic Chemistry, Vol. IX, p. 913. Colorless crystals, abs. Max. 335 mp., Steep abs, 400 to 420 mp., (Cf. Fig. 1, curve 1 *). Preparation: The free acid (see above) is dissolved in alcohol and decomposed with the calculated amount of sodium ethylate solution. The sodium salt crystallizes out.

*) The absorption limits given here and the curves drawn in Figs. 1 to 4 were measured with 1/2% solutions with a layer thickness of 2 mm in the solvents given. In addition, the absorption curve for a dilution of 1: 25,000 is given in the figures. Yellow crystals, m.p. 115 ° C.

Production: Beilstein, Handbook of Organic Chemistry, Vol. IX, p. 913. Yellow crystals, melting point 207 ° C. (see Fig. 4, curve 3). Production: Beilstein, Handbook of Organic Chemistry, Vol. IX, p. 912. White crystals, melting point above 360 ° C., abs. Max: 325 m # t, steep abs. At 370 to 400 m # t (see Fig. 1, curve 2).

Preparation: 22 g of the free dicarboxylic acid are mixed with the calculated amount of sodium ethylate solution. When a few drops of water are added, the yellow color disappears and the sodium salt crystallizes out. White crystals, melting point 62 ° C., abs. Max. 320 m # t, steep drop at 380 to 400 m # t (see Fig. 1, curve 3).

Production: Beilstein, Handbook of Organic Chemistry, Vol. IX, p. 912. White crystals soluble in methanol. Preparation: 11 g of acid are dissolved in 120 cc of warm isopropanol. 10 cc of cyclohexylamine are added while cooling and the mixture is left to cool in the refrigerator. Yield 18g. White crystals, melting point 128 ° C., soluble in methanol, abs. Max. 330 m # t, steep abs. At 390 to 400 m # t (cf. Fig. 4, curve 2).

Preparation: 77 g of acid are dissolved in 600 cc of isopropanol and 53 g of n-butylamine are added as above. Yield 120g. White crystals, sparingly soluble in methanol and ethyl acetate, melting point 121'C.

Preparation: 44 g of acid are dissolved in hot alcohol and mixed with 108 g of stearylamine, dissolved in hot alcohol; Let cool, vacuum, wash with alcohol and ether. Recryst. from ethyl acetate. Yield 127g. Almost colorless crystals, melting point 188 ° C., easily soluble in alcohol, abs. Max. 320 m # t, steep abs. At 380 to 400 m # t (cf. Fig. 2, curve 1).

Production: Beilstein, Handbook of Organic Chemistry, Vol. IX, p. 708. White leaflets, section max. 320 mp., Steep sections between 360 and 380 m # t (see Fig. 2, curve 2). Production: Beilstein, Handbook of Organic Chemistry, Vol. IX, p. 708. White crystals, melting point 82 ° C., section max. 323 m # L, steep section between 380 and 400 m # t (see Fig. 2, curve 3).

Production: Beilstein, Handbook of Organic Chemistry, Vol. IX, p. 708. White crystals, m.p. 52 ° C.

Production: 50 g diphenylbutadiene carboxylic acid, 200 ccm ethanol and 3 ccm conc. Sulfuric acid is heated on the steam bath for about 6 hours. The reaction mixture is poured into water, covered with ether and shaken. The separated ethereal solution is shaken with soda solution (to remove excess carboxylic acid), then washed alkali-free, dried and evaporated. Yellow oil, b.p. 0.4 mm 198'C production: 70 g of acid and 280 g of isopropanol are heated to 95 ° C. with 4 cc of sulfuric acid for 18 hours. The reaction mixture is then poured into water and extracted with ether. The ether solution is shaken again with soda solution, washed alkali-free, dried and evaporated. The ether residue is distilled at 0.4 mm at 198 ° C. Highly viscous oil, bp. O, o from 2 to 3 mm 199-202 ° C. Production: 100 g acid, 390 g isobutanol and 4 ccm conc. Sulfuric acid is heated to 95 to 100 ° C for 24 hours. Working up is carried out in the same way as in the two previous cases. The ether residue is distilled at 0.3 mm at 198 ° C. Yield about 80 g. Highly viscous oil, bp: 0.2 mm 198 ° C, section max. 325 m # t, steep section between 380 and 400 m # t (see Fig. 3, curve 1).

Production: Beilstein, Handbook of Organic Chemistry, Vol. IX, p. 708. Highly viscous oil, bp 4 mm 225 to 235 ° C, section max. 325 m # t, steep section between 380 and 400 m, (see Fig. 3, curve 2).

Preparation: 40 g of acid and 200 g of 1,2-propylene glycol are concentrated with 3 cc. Sulfuric acid heated to 100 ° C for 24 hours. After pouring into water, ether is extracted, the ether is washed with soda solution and water and dried. The ether residue boils at 0.4 mm at 225 to 230 ° C. Thick viscous oil, section max. 323 m # t, steep section between 380 and 400 m # t (see Fig. 4, curve 1).

Preparation: 85 g of acid and 300 g of butanetriol-1,2,4 are concentrated with 4 ccm. Sulfuric acid heated to 100 ° C for 24 hours. The reaction mixture is worked up in exactly the same way as in the previous four examples. The ether residue was not distilled. Yellowish white crystals, bp 3 mm 185 to 189 ° C, melting point 78 ° C, abs. Max. 325 m # t, steep abs. Between 400 and 420 m # L (see Fig. 3, curve 3 ).

Preparation: 25 g of phenylacetone and 25 g of cinnamaldehyde are mixed and saturated with hydrochloric acid gas while cooling with ice; Leave to stand for 24 hours. The viscous grease is dissolved in hot ethanol, filtered and strongly cooled - (C 02 / acetone). A solid mass is obtained. The alcohol is poured off and the residue is distilled in vacuo. At 0.3 mm and 185 to 189 ° C, a viscous oil is obtained that: Solidifies when treated with isopropanol. White crystals, melting point 152 ° C., abs. Max: 320 m # t, steep absorption between 360 and 380 m # t. Preparation: 50 g of diphenylbutadiene carboxylic acid (Beilstein, Vol. IX, p. 708), 50 cc of thonyl chloride and 50 cc of benzene are boiled for 5 hours. The thionyl chloride and benzene are then distilled off in vacuo and the residue is recrystallized from a mixture of carbon disulfide and petroleum ether. M.p. 93'C.

7 g of ethanolamine are added in portions to 14 g of this chloride, dissolved in 275 cc of ether. The resulting precipitate is filtered off with suction and recrystallized twice from methanol. White crystals, m.p. 177 ° C, abs. Max. 320 m ,, steep absorption between 360 and 380 m # t. Preparation: 27 g of the acid chloride described under 20 are dissolved in 450 ccm of ether. 19 g of cyclohexylamine are slowly added dropwise to this solution. The ether is then evaporated and the residue is recrystallized from benzene. Preparation: 20 g of o-chlorocinnamaldehyde, 20 g of malonic acid and 20 g of glacial acetic acid are heated on the steam bath for 5 hours. The precipitated crystal mass is filtered off with suction, washed with chloroform and recrystallized from ethanol. White crystals, soluble in water, m.p. over 360 ° C. Absorption ratios similar to the substance in the example s.

Production: 12.5 g of the dicarboxylic acid described in Example 22 are dissolved in about 300 cc of ethanol and: with a solution of 2.3 g of sodium in 50 cc of ethanol mixed. The pure white salt precipitates immediately; is extracted and washed with an ether-alcohol mixture.

Claims (4)

CLAIMS: 1. Ultraviolet. Radiation-absorbing light protection agents, characterized by a content of derivatives of 1-phenyl-butadiene- (1,3) of the general formula where X = C 0.OH, COO alkyl, C O alkyl, CONH alkyl, CON (alkyl) 2 or CN and Y = phenyl, COOH, COO alkyl or CO alkyl. 2. Ultraviolet Radiation-absorbing light protection agents according to Claim 1, characterized in that that the derivatives of 1-phenyl-butadiene- (1,3) as alkyl radicals are aliphatic or cycloaliphatic Contain hydrocarbon radicals with 1 to 20 carbon atoms. 3. Ultraviolet rays absorbing light protection means according to claim 1 and 2, characterized in that the hydrogen atoms of the benzene nuclei and the alkyl radicals carry substituents which do not exert a color-intensifying influence, for example halogen, hydroxyl, sulfo- or carboxyl groups. 4. Sunscreens absorbing ultraviolet rays; according to claim 1 to 3, characterized in that instead of the free carbon or Sulfonic acids the corresponding esters, amides or metal or amine salts are used will. Documents considered: German Patent No. 762 869.