DE1258527B - Process for the production of water-soluble coloring agents - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

C09b

German KL: 22 e - 2

Number: 1 258 527

File number: S 84420IV c / 22 e

Filing date: March 28, 1963

Open date: January 11, 1968

The invention relates to a process for the preparation of coloring agents from / 3-carotene and water-soluble high-molecular compounds which, when dissolved in water, give clear solutions.

^ -Carotene is a yellow to red dye that has a polyene structure with a long, conjugated double bond chain, and is known to be used as a coloring agent for foods, medicines, cosmetic articles and the like can be used.

jS-carotene is insoluble in water, hardly soluble in Alcohols and essentially slightly soluble in vegetable oils. Quite a number of procedures are available has been proposed to give the ^ -carotene chemical affinity to the water, whereby its use as a dye is to be facilitated. For example, hot /? - carotene is found in vegetable Oils are saturated, and the resulting mixture becomes an aqueous colloid of high molecular compounds added, resulting in a suspension in which / 3-carotene then for use as a coloring agent is dispersed (US Pat. No. 2,861,891), the colored suspension thus obtained becomes granules dried, which is used as a coloring agent (Japanese Patent 269,787), or it becomes / S-carotene dissolved in essential oils, and added to the resulting Solution becomes a surfactant or protective colloid to form an emulsion added (Japanese Patent Application 21 476/1961). However, these methods are disadvantageous because because they form suspensions or emulsions when used and tend to deposit jS-carotene crystals, which grow during heat sterilization or form creamy deposits or "neck rings". In addition, it is impossible to prepare these colorants in clear solutions, and therefore they can not to be used as clear solutions, such as those used in pharmaceuticals, cosmetic items, or foods required are.

It is an object of the invention to provide a process for preparing coloring agents from jo-carotene and water-soluble high molecular compounds which, when dissolved in water, give a clear solution. It has been found that, while overcoming the disadvantages mentioned, with low toxicity, high stability and high solubilities and suitability for use in foods, drugs and cosmetic articles, colorants are obtained which give clear solutions in water when / 3-carotene is used , if necessary together with antioxidants, and water-soluble high molecular weight compounds in the presence of a solvent which dissolves the / J-carotene and which the water-soluble processes for the production of water-soluble
Colorants

Applicant:

Sankyo Company, Limited, Tokyo

Representative:

Dipl.-Ing. K. Kiekeben, patent attorney,

1000 Berlin 19, Kaiserdamm 28

Named as inventor:
Tsunesuke Suyama, Tokyo

Claimed priority:

Japan March 30, 1962 (37-12 031)

ao dissolves high molecular weight compounds or has chemical affinity for them, mixes them under essentially anhydrous conditions and then removes the solvent.
A preferred embodiment of the process according to the invention consists in dissolving ^ -carotene and dibutylhydroxytoluene in chloroform at room temperature under essentially anhydrous conditions, mixing the resulting solution with powdered methyl cellulose and then removing the solvent.

Water-soluble high molecular weight compounds are, for example, polyvinylpyrrolidone, copolymers of Vinyl pyrrolidone and vinyl acetate and methyl cellulose derivatives such as methyl cellulose and methyl cellulose propylene glycol ether. It is expedient to use polyvinylpyrrolidone with an average Molecular weight from about 10,000 to 400,000, copolymers of vinyl pyrrolidone and vinyl acetate with an average molecular weight of about 40,000 to 115,000 and methyl cellulose derivatives an average molecular weight of about 30,000 to 140,000. In the process of the invention can be a single water-soluble high molecular compound or a mixture of a higher- and a lower molecular water-soluble high molecular compound or a mixture of two or more kinds of water-soluble high molecular compounds can be used. The choice of Kind of high molecular compound depends on the purpose of use of the water-soluble carotene dye away. For example, when used in alcoholic beverages or cosmetic preparations

709 718/383

is to be, as a high molecular weight compound that is also soluble in alcohols, such as polyvinylpyrrolidone or methyl cellulose propylene glycol ether is selected.

As solvents used in the method according to the invention in which /? - carotene is soluble and in which the water-soluble high molecular compound is soluble or to which it has chemical affinity has come z. B. chloroform, cyclohexane, carbon tetrachloride, benzene, methylene chloride or trichlorethylene into consideration.

The process according to the invention is carried out by mixing / 3-carotene with the water-soluble high molecular compound at normal or elevated temperature in the presence of the above-mentioned solvent under essentially anhydrous conditions. If the solvent used dissolves the water-soluble high molecular compound, it is appropriate to carry out the mixing in such a way that / 3-carotene is first dissolved in the solvent, if necessary with the simultaneous addition of an antioxidant, and then the water-soluble high molecular compound to the obtained solution is added. If the solvent used does not dissolve the water-soluble high molecular compound, but has the same chemical affinity, then the mixing can be carried out in such a way that the β-caiotia is first dissolved in the solvent, if necessary with the simultaneous addition of the antioxidant, and that then the resulting solution is poured onto the water-soluble, finely powdered high molecular weight compounds, with subsequent stirring. If an antioxidant is used, butyl hydroxyanisole and dibutyl hydroxytoluene can be used, for example.

In the coloring agents from / S-carotene and the water-soluble ones In the case of high molecular weight compounds, the way in which the components are bound is still unclear.

The use of the water-soluble colorants according to the invention results in carotene preparations of higher concentrations than those of the known preparations of aqueous suspensions or emulsions, who use vegetable or essential oils and they show a good coloring effect with lesser ones Amounts of dye. It is therefore possible to taste and To produce flavorings that are free from odor of the remaining coloring additive. In addition, the colorant produced according to the invention is little exposed to the influences of Subjected to light, temperature, pH, salts and the like, and it remains clear. It is not fraught with such disadvantageous phenomena such as crystal deposits, becoming creamy or "neck ring" formation. That according to the invention produced colorants can therefore be used in a wide range of preparations that Include foods, medicines, and cosmetic items. For example, it can be medical Liquids, alcoholic beverages or cosmetic waters that should be clear, as well as too Synthetic juices, milky lotions or cosmetic creams that are supposed to be cloudy can be added. aside from that Adding the coloring agents to foods or drugs enriches the precursor of vitamin A in addition to its coloring effect.

The solubilities of the produced according to the invention Colorants in various solvents are given in Table A below. In the table the results are given by naked eye observation regarding the solution status, if 0.005 g of the sample can be added to 100 ecm of a specific solvent.

Table A.

solvent 1 I 2 I 3 1111 + + 1111 4th example
5 I 6 I 7 I 8 Ml ++ M Il I 9 I 10 j - A I B MIM ί χ Distilled water - Ml ++ + + Ml M Il 1 1.0% aqueous citric acid, pH 2.15 ...
1.0% aqueous borate, pH 9.19
99 5% ethanol 50 ° / _o strength aqueous ethanol

- = clear;
- + = cloudy;
χ = insoluble.

The superiority of the colorants produced by the process according to the invention over those according to of British Patent 887 883, especially according to Examples 1 and 6 thereof, prepared dye preparations results from the following tables 1 to 5.

Table 1 contains a comparison of the physical properties of those produced by the two processes and examined products.

Table 2 shows that on storage the properties of the process according to the invention produced colorants change to a lesser extent than that of the British patent .887 883 produced dye preparations.

Table 3 shows that, in aqueous solution, the colorants prepared by the process according to the invention the dye preparations prepared according to British patent specification 887 883 with regard to the A = 2.4% α-carotene emulsifiable in water;

B = dry /? - carotene 1.5% dispersible in water.

Hue, transparency, adhesion to the container and stability are superior.
Table 4 shows that when introduced into aerated water, the colorants prepared by the process according to the invention are superior to the dye preparations prepared according to British patent specification 887 883 in terms of transparency and adhesion to the container in which the aerated water is located.

Table 5 shows that when added to some buffers for artificial fruit juices, the after the colorants produced by the process according to the invention are those according to British patent specification 887 883 Dye preparations produced in terms of transparency, adhesion to the container and the The hue given to the juices by this addition is superior.

Results of the comparative tests

Table 1 Physical properties of the two color substances

Color substance produced by the process according to the invention

(jS-carotene content: 5%)

Manufactured according to the method of British Patent Specification 887,883

Color substance (jS-carotene content: 15%)

Appearance

Amount of solution concentration:

2.5 mg (/ 3-carotene) per liter (water) of water (at room temperature)

Water (at 70 ° C)

red powder

solved in 19 minutes

dispersed immediately and dissolved after cooling

red-brown granules not completely dissolved in

60 minutes
resolved immediately

Table 2 Changes in storage of both color substances

temperature Properties examined According to the invention According to the procedure of Storage conditions Process manufactured
Color substance British patent specification 887 883
produced color substance duration solubility in water 03 carotene content: 5%) (/ 3-carotene content: 15%) (at 70 ° C) easily dispersible easily soluble ΛΟ / Ί, and after the 0 C hue Cooling dissolved (in aqueous solution yellow clear solution orange-yellow 2.5 mg / S-carotene per liter slightly cloudy solution remaining amount ; as / 3-carotene (%) 100 100 .OU solubility in water 1 (at 70 ° C) easily dispersible easily soluble ■ £ 3 room and after the Sh temperature hue Cooling dissolved (in aqueous solution yellow clear solution orange-yellow 2.5 mg / 3-carotene per liter) slightly cloudy solution I ' remaining amount read / 3-carotene (%) 99.5 100 solubility in water (at 70 ° C) easily dispersible hardly soluble 1 and after the , £> 40 ⁰ C ■ hue Cooling dissolved I. (in aqueous solution same shade far lighter tone than that 2.5 mg / 3-carotene per liter) like room at room temperature • pH remaining amount temperature ^ -Carotene (° / ₀ ) 98.5 immeasurable 2Woc solubility in water (at 7O ⁰ C) easily dispersible hardly soluble and after the 50 ° C ' hue Cooling dissolved (in aqueous solution same shade almost colorless 2.5 mg / J-carotene per liter) like room remaining amount temperature / 3-carotene (%) 93.5 immeasurable

Table 3

Physical properties of both color substances (in aqueous solution: 2.5 mg as /? - carotene per liter of water)

Properties examined

Manufactured by the process of the invention

Color substance (/ 9-carotene content: 5%)

According to the procedure of

British Patent 887

produced color substance

Oi-carotene content: 15 <yo)

colour

Hue*)

transparency

Adhesion to the container

Ring formation on the surface (after 5 days at room temperature)

stability
Color *) (exposed to UV radiation of

4000 lux times hours)

Tint *) (after lstündigem heating to 100 ⁰ C) ..

*) Determined with the color difference meter, + έ value.

Yellow 27.6 clearly none

no

26.8 25.0

Orange yellow 23.7

slightly cloudy something

no

21.9 14.8

Table 4

Physical properties of both color substances (in aerated water: 2.5 mg as /? - carotene per liter of aerated water)

Properties examined

According to the invention According to the procedure of Process manufactured British patent specification 887 883 Color substance produced color substance (/ 3-carotene content: 5%) (0-carotene content: 15%) yellow yellow clear slightly cloudy (Formation of precipitation) no some no no

colour

transparency

Adhesion to the container

Ring formation on the surface (after 1 month 'at Room temperature)

Table 5

Physical properties of both color substances (in some buffer substances for artificial fruit juices: 5 mg as /? - carotene per liter)

pH the
solution Color substance produced by the process according to the invention Ad
adhesion Ring formation
at the room Hue*) 100 ⁰ C, Trans to the surface temperature According to UV 1 hour ttarenz * *) container (after 1 month) 30.6 Irradiation 27.3 2.5 no no 31.0
31.1
31.1 28.8 29.0
30.3
29.7 3
4th
5 _ no
no
no no
no
no 30.6 30.1
30.6
30.7 30.3 In an aqueous solution of tartaric acid,
and its sodium salt 6th - no no 30.5 30.5 25.2 2.5 - no no 30.6
30.6
29.9 28.2 27.2
27.7
28.0 3
4th
5 - no
no
no no
no
no 30.1 29.9
29.7
29.8 27.1 In an aqueous solution of phosphorus,
acid and its sodium salt 6th - no no 30.6 29.9 26.5 2.5 - no no 30.7
31.0
30.6 28.4 28.2
29.7
30.1 3
4th
5 - no
no
■ none no
no
no 31.0 29.0
30.3
30.3 29.2 In an aqueous solution of lemons
acid and its sodium salt 6th - no no 30.5 - Footnotes at the end of the table.

Table 5 (continued)

pH the Trans Following the procedure of British Patent Specification 887 883 manufactured Color substance Farhtnn * Λ 100 ⁰ C, solution parence **) Ring formation Γ <XL U LUIi J 1 hour Ad at the According to UV 11.3 + adhesion surface room Irradiation 12.5 2.5 + to the (after 1 month) temperature 27.1 5.6
12.8 3 +
+ container some 32.9 26.6 19.3 4th
5 + some some 32.6 22.6
22.1 16.2 6th + some some
some 31.8
32.3 27.0 13.0 In an aqueous solution of tartaric acid.
and its sodium salt 2.5 + some
some some 32.9 26.1 3.3 3 + some some 31.3 25.9 12.9 4th + some some 31.1 22.5 18.0 5 + some some 29.2 20.6 17.5 In an aqueous solution of phosphorus, 6th + some some 31.1 26.0 16.3
9.8 acid and its sodium salt 2.5 +
+ some some 31.9 27.3 4.6 3
4th + some some 32.1 27.0
24.6 23.0 5 + some some
some 32.0
31.0 21.4 In an aqueous solution of lemons 6th some
some some 29.7 27.9 acid and its sodium salt some some 32.7 some

*) Determined with the color difference meter, +6 value.

- means "clear"; + means "cloudy".

The invention is explained in more detail below using a few exemplary embodiments.

example 1

100 mg crystalline / 3-carotene, 1856 mg polyvinylpyrrolidone (average molecular weight about 360,000), 40 mg of dibutylhydroxytoluene and 4 mg Butyl hydroxyanisole are dissolved in 10 ecm chloroform, and the resulting solution is poured onto a glass plate sprayed, then the solvent is removed by evaporation, so that a red Colorant received as a film.

Example 2

100 mg crystalline / 3-carotene, 1856 mg polyvinylpyrrolidone (average molecular weight about 40,000), 40 mg dibutylhydroxytoluene, 4 mg butylhydroxyanisole are dissolved in 4 ecm chloroform, and the resulting solution is spray-dried to remove the solvent to give a red colorant.

Example 3

The same procedures as in Example 1 are repeated with the exception that a copolymer of vinyl pyrrolidone and vinyl acetate (60:40), average molecular weight 40,000 to 115,000 Place of the polyvinylpyrrolidone according to Example 1 is used, using a red colorant as Film receives.

Example 4

100 mg crystalline / 5-carotene, 660 mg polyvinylpyrrolidone (average molecular weight about 360,000), 700 mg of the same (average molecular weight about 40,000) and 40 mg of dibutylhydroxytoluene are dissolved in 5 ecm of chloroform, and the The resulting solution is heated in order to remove 2 to 3 ecm of the chloroform by evaporation. the remaining mass is mixed with 1900 mg of anhydrous glucose powder, and the mixture is mixed with the usual methods for the production of granules treated.

Example 5

To 100 mg of crystalline ^ -carotene, 40 mg of dibutylhydroxytoluene and 4 mg of butyl hydroxyanisole are added to form a solution of 10 ecm of chloroform. 1856 mg of methyl cellulose (average molecular weight 30,000) are added to the solution. given and mixed to a homogeneous mixture and then made a fine granulate from it. The solvent is then removed from the granules by evaporation, whereby a receives red dye.

Example 6

To 100 mg crystalline / 3-carotene, 40 mg dibutylhydroxytoluene and 4 mg of butyl hydroxyanisole are added to form a solution of 10 ecm of chloroform. 1856 mg of methyl cellulose (average molecular weight 140,000) are then added to the solution. added and mixed to a homogeneous mixture, with subsequent formation of fine granules. The solvent is then removed from the granules by evaporation, a red colorant being obtained receives.

Example 7

To 100 mg of crystalline ^ -carotene, 40 ml of dibutylhydroxytoluene and 4 mg of butylhydroxyanisole are 10 ecm of trichlorethylene to form a solution added. 1856 mg propylene glycol ether of methyl cellulose (average Molecular weight about 60,000) and mixed to a homogeneous mixture, followed by Production of fine granules. The solvent is then removed from the granulate by evaporation removed to give a red colorant.

709 718/383

Example 8

To 100 mg crystalline / 3-carotene, 40 mg dibutylhydroxytoluene and 4 mg of butyl hydroxyanisole are added to form a solution of 10 ecm of chloroform. 928 mg of methyl cellulose (average molecular weight approx 40,000) and 928 mg propylene glycol ether of methyl cellulose (average molecular weight approx 60000) and mixed to a homogeneous mixture, with subsequent formation of a fine Granules. The solvent is then removed from the granules by evaporation, leaving a red Colorant receives.

^{Example9 1S}

To 100 mg of crystalline ^ -carotene, 40 mg of dibutylhydroxytoluene and 4 mg of butylhydroxyanisole are trichlorethylene and 8 ecm to form a solution 2 ecm of methylene chloride added. 1856 mg of propylene glycol ether of methyl cellulose are added to the solution (average molecular weight about 60,000) and to a homogeneous mixture mixed, with subsequent formation of fine granules. The granulate then becomes the solvent removed by evaporation to give a red colorant.

Example 10

To 50 mg of crystalline / J-carotene, 20 mg of dibutylhydroxytoluene and 2 mg of butyl hydroxyanisole are added 10 ecm of benzene to form a solution. 1928 mg of a copolymer of vinylpyrrolidone and vinyl acetate (60:40), on average, are added to the solution Molecular weight 40,000 to 115,000 given to form a solution. The solution will be sprayed onto a glass plate, and the solvent is then removed by evaporation, wherein a red dye is obtained.

Claims (2)

Patent claims: 1. Process for the production of water-soluble colorants, characterized by that one / J-carotene, together if necessary with antioxidants, and water-soluble high molecular compounds in the presence of a Solvent which dissolves the ß-carotene and which dissolves the water-soluble high-molecular compounds dissolves or has chemical affinity for them under essentially anhydrous conditions mixes and the solvent is then removed. 2. Process for the production of water-soluble colorants according to claim 1, characterized in that that one /? - Carotene and dibutylhydroxytoluene in chloroform at room temperature under In essentially anhydrous conditions, dissolves the resulting solution with powdered methyl cellulose mixes and the solvent is then removed. Considered publications:
British Patent No. 887 883. 709 718/383 12.67 © Bundesdnickerei Berlin