DE2001504C - Process for the production of pearls - Google Patents

Description

The invention relates to a method of manufacture \ on pearls by crystallizing at least one of the compounds from the group Nuclein-ν acids and their compounds in aqueous solution.

The following conditions must be met in order to produce pearls and achieve a pearlescent luster can be achieved: The reflex index must be high, the crystals must be colorless and transparent;,? and in the form of thin platelets from 5 to 100 microns in length and 500 to 500 in thickness 1200A, the crystals must also be smooth Have surfaces, be chemically and optically stable, be heat-resistant, soluble in organic Solvents and be readily dispersible in paints.

So far, largely microcrystalline lead carbonate has been used than crystals corresponding to the above Requirements for the pearlescent luster are applied.

Fs is also known. Manufacture of pearls on a guanine basis. The extraction of guanine crystals for pearl essences is made from fish scales by treating them with water and wetting agents (cf. the literature reference "Soap-Oils-Fats-Waxes". 1961. No. 24. P. 801).

These known procedures were therefore due to the uncertainty of the fishing yield as well as the salary the fish scales depend on effective crystals with a pearlescent sheen.

A difference in the type of fish leads to a difference in the crystal shape, thereby creating the strength of the gloss and the weight of the product can be influenced. Because of this, let Do not manufacture products of a standard quality.

Furthermore, fishing yields are decreasing in Europe, America and Japan. while demand increases. For this reason, an increasing demand for fish scales cannot be met. In particular it must also be taken into account that the yield achieved by the fish scales is by no means covers the cost of fishing.

For this reason, fish scales are not suitable as a raw material for modern industry. which products with standardized quality are to be manufactured on a large scale. * Demücnen over the invention echoes a process, at which thin platelet-shaped crystals \ on nucleic acid or its derivatives, which are widely used in animals and plants and which are generally known as starting maieriahen use for condiments and medicines; will. The method according to the invention can be run on a technical scale. The invention therefore has the following advantages:

1. Hs become cheap and readily available materials used.

2. Since the starting material does not contain any contaminants such as fish scales, e.g. B. Fish oil. Fet Protem. small pieces of fish skin or del., the end products are not thereby \ err unreasonable.

3. Since there are ■ impurities. ;-that Weatherproof product.

4. By regulating the manufacturing conditions constantly manufacture products with standardized quality. For this reason, be wise. the products have a uniform pearlescent luster: Furthermore, the crystal shape can be changed by the production conditions are changed: so that the strength of the pearlescent luster is artificially regulated can be.

5. The manufacturing process is simpler and the yield is higher than that of the known process. Furthermore, large-scale production is possible, so that one can also increase: Demand can be satisfied without further ado:

6. Fine intergrowth between crystals like he the fish scales hardly appear. so that it is easier for you to handle Kristille.

7. The products produced according to the invention have superior properties. since they non-toxic and resistant to chemicals. Are warmth and light.

The product manufactured according to the invention .: can therefore be used for all purposes in which conventional pigments are used were: they are also suitable for use in k ismetics. Food and beverages. Dinnerware and toys.

In order to produce a pearl essence, a material with a high refractive power must first and foremost be used be applied. The master. Nucleic acids and their corresponding nucleic compounds exhibit great refractive power and are ideal as pearls. if they form microcrystals, which meet the above conditions for a pearlescent luster.

In the applicant's earlier Offenlegungsschrift 1 930 265, there is a method for producing Pearl essences from nucleic acids or their derivatives are described. In this procedure, however, passed there are certain difficulties when starting materials with a low degree of purity have been used the impurities create the optimal crystallization conditions were affected.

Further investigations into this problem within the scope of the invention have now shown that the impairment the optimal crystallization conditions of the PerlesEnzen avoided by impurities can be achieved if one uses an ionic

iächenakuves means / u of a solution of the nucleic acids or their compounds prior to crystallization. Here one also obtains in the presence of -., - η impurities in simple form and; n large yield crystals of nucleic acids' or their compounds with strong pearls / and more uniform Crystal size.

A process, therefore, creates a process, / to manufacture, ", of pearls / en under Vcrv-cndun ^ ,, ^ _n ^ uc! E :: isacids or their nucleic linkages. ' .. soft bar are cheap and in groiVr Menüe commercially verfi ^ The special \ ie> eründunjsgen ^:.: -i> cn process is then dai3 rr.an the ^K.ri>: ..i'l ^{'>; | IION.} ' ⁿ presence νr, r, i bisM.iHil (lewicht-pri', - e: v .. based on da- weight of the w.ibrüien Lö -.::- g- at least one ionic '"' beriLidienaktiv -n Sto :: - executes.

1·. So it was found that dal · nia: i denotes the 1-ir.fiuls ger: ·: .er quantities of pollution. ·! -, .ιa 'd: e,' piK-alen Kn ■■ ".aihsaiiensbedingungen der Nuclein'.erbind'ip. ^ En au- A..Uriger solution switch off k .-. nn. if the aqueous solution during the preparation of the Solution or shortly before or after the deposition of the first microcrystals of the nucleic compound added v. earth.

Suitable nucleic acids or their compounds within the scope of the invention are, for example, Pvrirnidmnu.leinbasen. Purine nucleic bases and their derivatives These nucleus compounds correspond to Above requirements for pearl essences if the crystallization conditions correspond to 1 selected will.

The used nucleic acids resp. their compounds correspond to the pyrimidine nucleobases of the following general formula:

R-.

R-

R.

ion: ·· -he (cationic. amon: -

or amphoteric

^height::. Stotie active surfaces / u a vv.iiJrmen I o>un> · before nucleic acids or compounds thereof /uuibt.· dab ·, one obtains crystals with uniform nlauer OKnlaehe and Peflglan / in a simpler manner and mi: higher yield ah K , the, conventional Vef their.

The mechanism of the /u-.it/e·· \ on '»herflachenak' -en substances in the en-nciigemabeti author; i '" en is still not known. One can assume, however, that obcrdiichenaktr. e ShMTe the t ^; iiiensci ".,;i'ien. the density read-out and the dilution-7i; -inJ the solution of these ν influences υπ ·; The solution is in a state favorable for the formation of the thin, ply-shaped microcrystals ... sct / t. The method according to the invention / in order to produce l ^{5 / s.} In which ionic surface active substances for the formation of uniform and smooth crystals can be obtained in a simple manner and in high yield from nucleic acids or their compounds is completely new.

\ ls cationic surfactants in the For example, wet nurses and their salts, quaternary ammonium salts, are suitable. Pvndinium sal / e. Picolinium sal / x. Zelan-T \ p \ erbindungen. Belan-type connections. Amine formaldehyde condensation products. as well as stearon-chromlllU-chlond. Alkyl sulfates, for example, are suitable as anionic surface-active substances. Alkylbenzenesulfonates. Alkyl naphthalene sulfonates. Naphthalenesulfonate - l-orrnaldehyde - condensation products. Alkyl phosphates. Amidosulfonates and sulfosuccinate dialkyl esters. As amphoteric surface-active substances are suitable of the invention, for example betaine compounds (e.g. Alkyl betaine), sulfoxylate compounds (/ .. B. Hydroxyalhylenimidazoline sulfoxylate). Su Ifonat compounds. Phosphate compounds and the like

The appropriate concentration of the nucleic acids or their compounds to crystallize Surfactants applied may vary depending on the type of surfactants and the new compounds vary. In general however, a concentration of 1 to 0. (K) I percent by weight, based on weight the aqueous solution of the nucleic compounds. to be prepared. The surfactants can too

R,

in which R _{1 is} hydrogen or an alk group with 1 to 4 carbon atoms. R- the meaning of hydrogen or an alkyl group with 1 to 4 carbon atoms. R, the meaning of OR.,.

R-

or hydrogen. R _-1 the meaning of hydrogen. OR ₁₁ .

R ₁₁ ,

R,

NO or an alkyl group with 1 to 4 carbon atoms: R _{4 means} hydrogen. OR ₁₂ .

Ru

■ -N

NO or an alkyl group with 1 to 4 carbon atoms. R ,,. R ₉ and R ₁₂ each have the meaning of

Hydrogen. Alkyl groups with 1 to 4 carbon atoms or OCOR ₁₅ . R ₇ , R ₈ . R ₁₀ . R _n - Ru ^{and R} u each represent hydrogen or alkyl groups having 1 to 4 carbon atoms and R ₁₅ represent alkyl having 1 or 2 carbon atoms

bo owns. Also suitable are pyrimidine nucleosides of the above formula, in which R, a penlose, such as ribose. Arabinose or xylose, or an acetyl derivative or an isopropylene derivative or a hexose. like glucose. Means mannose, or fructose.

6s derivatives of pyrimidine nucleosides. Nucleotides of the above formula in which R _{1 is} a pentose with a 'phosphate group in the 2'-. (3) - and or 5 'position. Metal salts of nucleotides such as alkali salts.

Alkaline earth salts and aluminum salts. Amino acid salts
of nucleotides and various derivatives of
Nucleotides in which hydrogen atoms of phosphate are substituted and a structure of the following
Have formula:

O OR ,,.

R means hydrogen or - Σ »- ^K .: -« · ¹ Ji? _{4 K} ohler -offotomen: R ₂₁ die or alkyl with » ^bl ^ _{r <} . _{substance 0:} alkyl with! to meaning \ on ^ - ^ ^ _{julung νΰ} η water carbon atoms. ^ ^ _carbon ff _alom en or stoff or alky, mi

- P

OR-

in which R, “and R, - the meaning of W a> s <
atoms. Alk)! with 1 to 4 carbon atoms.

-CH-

NO-

mean.

These pyrimidine nucleic acids and their compounds generally occur in nature. Of these compounds, the f'-l'ridylic acid and 5 '- (' ytidyl acid are mainly used. Soft al> by-products in the production of 5-inosinic acid and 5 'apply -Guanylsäure ⁿⁿ d tasty nucleotides from ribonucleic ^ AURC represents the Uridyl- and C'xtidylsäure were bivier technically unusable in addition, the salts and derivatives are the Uridyl- and (ytidylsäure:.... l'ridm C'ytidin uracil and Cytocin, which can easily be obtained by chemical and or enzymatic decomposition of these acids, salts and derivatives;

The nucleic acids and their compounds used in the context of the invention exist from purine nuclein bases of the following general formulas:

R ₁ ,

C - R; "

K ₁ ,

H
N

C - O

in which R, _H and R ₁₉ mean hydrogen. OR, · ,.

- N

R ₂₄

- C

■ Rv,

Asserstolfatome or Alk)! groups

mil 1 to 4 K ^nit " ^s - ^ ₄ carbon atoms b ^ nzu

xon Alk>' ^ml : ρ _innuc ieoside of the above formula, also suitable ..J ₁ I u .. _{j (; ntosc} _ ^ _R ^ . ". ^, ^

_m where _{n: f IsoPro} pvridinderiN; te here-

or Ny.o ^ .A- ^. ^ _Glucose . Mannose or

^{% on} - ^{l> di: r} , ^C T-.iiet derivatives of nucleosides. Nudeo-,. 'Ruciose hed, ta U ^^^^ ^^. _p ^^

^liJ ^ "Ä: oha Ure in the 1-.UV-M ₁ Md ^ r

and or a! / e the e u: -d AIu-

w. amino acids aer ^ «iia.uuc and mmiunisaiz ,. ^ _{1 ,,} ^ Nuc | _e olidc in wek: - the, published IXm ^ _{ph hats sub} stituie: i sind ^ ■ ri ^ Suurdiu.igenden formula arise:

, ,,. _{R il}

^{111 uu>} "'■;'", ^. ,, ^
groups η, .ι ■

O OR; -

OR; s

R, _s WassersioffaiouK

C \ U

- ■ NO,

6o ■ urine nucleic acids and their compounds ■ ilKTciv.em m of nature. For these juntins, inosic acid is mainly used for mn Xahm. 5'-guanylic acid. 5 -Ade _n . _K : _lU re and their salts and derivatives used O, cse compounds have recently had teenage customers and are manufactured in technical dimensions: inosi ,, cuanosine are also suitable. \, t-nosine lUnmanthin. Guanine and adenine, which Yr ..inf-i-hcr way as intermediates in the Herü'ellunV these acids or by chemical decomposition and these acids are obtained or en / ymatische decomposition. ■, · ,,, .- η ■

'Frlin' and you can use crystals for pearl essence produce in a uniform size and greater yield than in the known process

The Frfindun "creates a process of manufacture of pearls by precipitating crystals and nucleic acids or their compounds from a aqueous solution in which an ionic surfactant is applied. The remaining Crystallization conditions. apart from the presence of the surface-active substance, for example that Cooling the pH change by adding a solvent etc .. can depending on the type of

nucleic compounds used and the type of surfactant used will vary. Such an aqueous solution of the nuclcine compound is preferably used. that 'until' ₄ . preferably V ₃ to ² ', of the solute, are precipitated in the course of 30 minutes, preferably in the course of 10 minutes, and the remaining unprecipitated nuclcine compound is precipitated gradually in the course of 1 hour to 1 day. This method was only recently invented by the inventors of the present application (see laid-open specification 1 930 265).

Corruption thus became a hitherto unresolved issue Technical problem overcome, which has not yet been solved by the aforementioned disclosure was (such as achieving a uniform size. Shape and thickness of the crystals of the for pearls / en Nuclcin compounds used).

So far, for example, it has been very difficult to find the Proportion of the deposition of guanine from an ammoniacal solution on a boiling water bath to regulate escaping ammonia, so that they very often formed needle-shaped guanine crystals Even if very precise regulation of the crystallization conditions results in thin platelet-shaped Crystals formed, these were very different in size. Form and strength on: furthermore it had to be as The guanine used as the starting material must be of high purity. Even if you have a guanine with a purity of Applies over 99%, the crystallization in the absence of a surfactant produces large and small crystals. Even if the size of the crystals obtained is an average eye of 3 to 100 microns, a width of 1 to 40 and one Thickness of 0.05 to 3 microns! The size distribution of the crystals lies in a very broad Hreich. Such crystals therefore have at least a similar "pearl" as natural fish platelets on.

By adding surfactants, crystals of the desired length and width can be obtained obtained in a simple way. For example, you can get any crystals in a size of 15 or 20 microns receive. It is also possible to have all crystals in a square, pentagonal, or hexagonal shape receive. In addition, relatively thin crystals with a thickness of 0.1 to 0.03 microns can be produced. The pearlescence of the crystals thus obtained was greatly increased by this method.

The following advantages are achieved by adding surfactants:

(1) The crystals are uniform in size and shape.

(2) Thin crystals can easily be obtained.

(3) Obtained even from impure raw materials one the desired crystals.

(4) The amount, and hence the yield, of the crystals is also increased because the crystals are uniform Size and shape.

(5) The pearlescence is enhanced as the shape. size and the strength of the crystals is uniform

The pearl essences and their compounds obtained by the process according to the invention have outstanding properties in every respect. such as B. in terms of chemical resistance. Heat resistance and lightfastness: they also have a strong pearlescent sheen. This Essences are cheap and non-toxic and can of course be used in all areas of application conventional pigments either in the form obtained during production or after the corresponding Formulation to be used for the specific purpose. You can also, for example in the manufacture of cosmetics. Food. Drinks. Dishes or toys in the fabrics

ίο be introduced or applied as a coating.

The invention will now be made based on the following

Examples further explained. All parts and percentages in the examples relate to weight.

'5 Example 1

20 g of white powdered uracil (purity 93.8 "ti) were added to I I distilled water and brought into solution by heating. The on this Solution obtained in this manner is referred to as solution A hereinafter. I g of alkyldimethylbenzylammonium chloride as a cationic surfactant was added to 9 liters of distilled water. The so solution obtained is referred to as solution B in the following. The solution A was taking at once Stirring was added to solution B and the mixture was gradually raised to 20 ° C. over 3 hours abfckühll: thin platelets formed Microcrystalline with a size of less

_io than 1 micron. Then the stirring was quickly slowed down, and the mixture was slowly cooled to 0 C over 1 hour. There were perigiänzeiide KiimuÜc with g'unier surface, one Length from 1.5 to 20 microns, width from 10 to

.15! 5 microns and a thickness of 0.08 microns. The reaction was continued under these conditions for a further 2 hours, being louder Crystals with the above dimensions were obtained and the solution was strongly streamlined Exhibited pattern. The crystals thus obtained were filtered off from the solution, dried and coated with resins mixed. The resulting mixture was compression molded or processed by injection molding, wherein a molded synthetic resin product with pearl glass / was obtained.

Example 2

20 g of white powdery cytosine (purity 97.2 ",. I were added to 2 liters of distilled water and the resulting mixture was heated in Solution brought. The solution was cooled to 50 ° C. and then 1 g of the sodium salt was added of polyoxyethylene alkyl ether anionic surfactant added to the solution. Subsequently methanol was added to the solution in an amount before 50 ml min., whereby Microcrystals about 1 micron formed die The solution was cooled to 0 C in the course of 1 hour and at this temperature for a further 2 hours held, with strong streamlines shaped pattern appeared in the solution. The no received thin platelet-shaped crystals were rectangular or rhombic and had a through diameter of 15 microns, a width of 10 microns and a thickness of 0.1 micron. The crystals were filtered off. collected, ge with methanol wash and air dry. Then a paste was made from the crystals, a solvent, a r

309 636 33

Dispersants and resins. This Pa.sie was appropriately diluted, leaving a pearlescent finish Color was obtained.

Example 3

20 g of white, powdery hypoxanthine (purity 04.5%) were converted into 10 1 of 0.5 normal aqueous ammonia added and brought into solution while warming. 0.5 ml of an organic dibasic Alkyl ester sulfonate as an anionic surfactant was added to the solution. That in the The ammonia present in the solution was evaporated on a boiling water bath, becoming thin Plate-like microcrystals formed with a thickness of less than 1 micron. This solution was slowly cooled to 5 ° C. over the course of 5 hours, needle-shaped microcrystals precipitating out. The solution was then slowly stirred for 2 hours at 5 C, with a strong streamlined appearance Pattern appeared in the solution. The crystals obtained were shaped like fish flakes and had a 15 to 20 microns in diameter, 2 to 3 microns wide, and 0.08 to 0.1 microns thick on. The crystals were suctioned off and the moist crystals by rapid evaporation of the surface dried existing liquid and then washed with methanol. The so obtained Crystals were mixed with essential essences, with excellent pearls being used Achievement of pearlescent was obtained.

Example 4

20 g of white powdery guanine (purity 97.0%) was dissolved in 91 0.5 normal aqueous ammonia dissolved with heating. The ammonia was evaporated from the solution on a boiling water bath, whereby microcrystals less than 1 micron in size were obtained. The crystals were filtered off, and the filtrate was with 100 m! a 1% aqueous solution of a sodium salt polyoxyäthylenalkylphenyläthersulfonsäure added as an anionic surface-active substance. The The mixture was left to stand in a room with a temperature of 5C. After about 10 hours Rectangular or square crystals 10 to 15 microns in diameter, one separated 5 to 10 microns wide and 0.07 microns thick. The crystals were sucked off, the liquid on the surface of the crystals was quickly evaporated, and then the Crystals washed with methanol and then dispersed in nitrocellulose. 20.2 parts of that in the nitrocellulose dispersed crystals, 7.5 parts of a condensation resin of toluenesulfonamide, formaldehyde and alkyd resin, 3.8 parts of dibutyl phthalate, 25.3 parts of butyl acetate, 6.4 parts of ethanol, 1.1 parts of butanol, 32.7 parts of toluene and 3.0 parts of a dye were mixed together. It was a manicure liquid Preserved with a good pearlescent luster.

Example 5

50 g of white powdery adenine (purity 98.5%) were added to 500 ml of 0.5N hydrochloric acid and under Heating resolved. The solution thus obtained is hereinafter referred to as solution A '. Separately from this a solution of 0.5 g of an alkyl betaine amphoteric surfactant in 91 was distilled Water produced; the solution is referred to below as solution B '. The solution A ' was added all at once to the stirred solution B '. The pH of the solution was through Adding 0.1 η sodium hydroxide to 2.8 a

placed. The solution was then cooled to 5 ° C. over the course of 2 hours with stirring, during which Adenine microcrystals precipitated. At this point the stirring was stopped and the Let the solution stand at 5 ° C. After 5 hours

ίο the microcrystals grew into uniform crystals about 20 microns in diameter, 2 to 3 microns wide, and about 0.1 microns thick. A strong streamlined pattern was observed when this solution was stirred :. The obtained crystals were filtered and completely dehydrated by flash evaporation. 2 parts of the thus obtained thin plate-shaped crystals of adenine, 100 parts of polyvinyl chloride resin. 4.8 parts of dioctyl phthalate, 0.7 parts of cadmium stearate and 0.5 part of barium stearate were mixed together and kneaded on a roll of 170 C ^3. The resulting mixture was passed through a calender roll to obtain a pearl-shaped sheet.

B e i s ρ i e 1 6

15 g of white powdery guanine (purity 97.O ⁰ O) and 5 g of white powdery hypoxanthii were added to 9.5 l of 0.5 normal aqueous ammonia, and the resulting mixture was brought into solution by heating. The ammonia was

: ηκ HfMW r ^ r »r ^; _f ..l c ,: _ -.j .. j .. u ·, ^ K ^ / i

"" .., VJV-IiIiO,. !! _until CIII MCUCIIUCII »jmhw» evaporated, thin platelet-shaped microcrystals less than "!

the filtrate was with 150 ml of a Γ / o aqueous solution of a mixture of a sodium salt of Polyoxyäthylenalkyläthersulfonsäure and a sodium salt of Polyoxyäthylenalkylphenyr ^; added thersulfonic acid as an anionic surfactant and allowed to stand in an environment of 5 ° C. After about 5 hours, crystals 25 to 30 microns in diameter, 5 to 6 microns wide, and 0.OS microns thick were obtained. The shape of the crystals was compared microscopically with the shape of fish flakes obtained from herrings. As a result, it was found that the crystals were very similar to each other and the size of the artificially produced crystals was very uniform. while the dimensions of the fish platelets

were not uniform.

The crystals obtained in this way were sucked off and the crystals adhered to the surface of the crystals. Moisture removed by flash evaporation: the crystals were then ge with methanol

to wash. 150 parts beeswax, 10.0 parts lanolin, 4.0 parts carnauba wax, 2.0 parts bromic acid 5.0 parts of cetanol, 49.0 parts of castor oil, 4.0 parts of cere sin. 10.0 parts of the guinine obtained (paste) unc 1.0 part of perfume was mixed together unc

processed into lipsticks. The lipsticks had a strong pearlescent sheen.

Example 7

Methanol was dissolved in 100 ml of a 20% aqueous solution

Solution to white powdery cytidine (pure

hay 97.0%) in an amount of 50 ml per minute

added dropwise. Just before the deposition of crystals!

5 ml of a l% i _gen solution of an alkylaryl

sulfonic acid was added to the solution as an antonic surfactant. Then it became methanol again added dropwise to the solution, whereby microcrystals precipitated. At that point it was the stirring was stopped and the solution was gradually reduced by lowering the temperature of the water bath .Cooled to 5 ° C in the course of about 1 hour. This> became practically square or rectangular crystals about 5 microns in diameter and obtained about 0.1 micron thickness. The crystals were filtered off, washed with methanol and turned on air dried. The dried crystals were resuspended in methanol and the resulting suspension was stirred. It was a streamlined Pattern preserved with an excellent pearlescent luster. Achieving this pattern proves that you can use the crystals as desired pearl essences.

V ⁱ²

: edged. where a Pa:

Example 8

21)

1 1 of a 0.5% suspension of needle-shaped guanosine crystals (purity 92.5%) were through Warming on a water bath brought into solution. Then ethanol in an amount of 30 ml per Minute added. Thin needle-shaped or rectangular microcrystals of one size fell less than 3 microns. At this point, 1 ml of a 1% aqueous solution became a Oleic acid amide sulfonate was added as an anionic surfactant, and the solution was im In the course of 5 to 10 minutes, the mixture was rapidly cooled to 5 ° C. with stirring, and this was about 1 hour Temperature held. At this time, a streamlined pattern appeared and became in the solution Crystals in the form of smooth platelets with a diameter of about 25 to 30 microns, a width of about 10 microns and a thickness of about 0.1 to 0.12 microns. The crystals were filtered off, whereby a cake having a moisture content of 20% was obtained. 5 parts of this Wet cake was mixed with 10 parts of a tragacanth solution (2%), 5 parts of glycerin. 0.8 parts of castor oil. 5 parts of stearic acid. 2 parts propylene glycol stearin. 0.4 parts triethanolamine. 71.8 parts of water and a small amount of perfume and an antiseptic mixed. A cosmetic milk with a very beautiful pearlescent luster was obtained.

Example 9

To 100 parts of an aqueous paste of thin. plate-shaped, in the same way as in the example 1 uracil crystals produced were 19 parts a saturated polyester resin with a content of 5% sorbitan monooleate was added. The received The mixture was stirred and the separated water was decanted off, leaving a paste with a Water content of 9% was obtained. This paste was made 3 hours at 55 C under reduced pressure dried. The dehydrated paste was dispersed in 100 parts of methyl isobutyl ketone. and the dispersion was added in an amount of 1% to an acrylic resin or a semi-polymerized polyester resin. The resulting mixture was placed in a metal cylinder, which was then sealed and and rotated to allow thermal polymerization to proceed (so-called conventional centrifugal method). A cylindrical polymer with a wonderful pearlescent luster was created receive. The heat resistance, light resistance and hydrogen sulfide resistance of a sample of the obtained cylindrical polymers were examined. The heat resistance was checked. by placing a sample in a hot air oven at 150 ° C for 6 hours and observing the color. The light resistance was examined by placing a sample in a fadeometer for 25 hours exposed at 55 C in accordance with JIS-L-1044-1959 and then determines the color. The hydrogen sulfide resistance was lasted for 30 minutes Heating a sample in a solution saturated with hydrogen sulphide at 40 "C and then heating it Observation of the color noted. In these experiments it was found that the uracyl-containing acrylic resin and the uracyl-containing polyester resin was not discolored. On the other hand occurred under the same test conditions in the case of an acrylic resin or polyester resin, which contains microcrystals of bismuth chloride, Containing lead arsenad or lead carbonate and prepared in the same manner as above. one each Discoloration under the above test conditions, with certain differences in the degree of discoloration were observed.

Example 10

Using an aqueous paste of thin plate-shaped, according to that in Example 4 The method described in the guanine crystals (crystal concentrate 55%) was an acrylic resin plate or a polyester resin plate prepared in the same manner as in Example 9 and the same Way as in Example 9 investigated. There was no discoloration or change in the Pearlescent.

Example 11

The cosmetic milk obtained according to Example 8 was stored in a fadeometer at 55 ° C. for 25 hours exposed according to JIS-L-1044-1959. There was none Discoloration of the milk or a change in the pearlescent luster.

Claims (3)

200! Patent claims: 1. A process for producing pearls by crystallizing at least one of the compounds from the group of nucleic acids and their compounds in aqueous solution, characterized in that the crystallization is carried out in the presence of from 1 to 0 001 · , c percent by weight. based on the weight of the ic aqueous solution, executes at least etnos ionic surfactant. 2. The method according to claim 1, characterized in that the starting material for the pearls at least have a zero base from the Guanine group. Adenine. Hypoxanthine. C \ losin or L racil used 3. The method according to claim 1, characterized in that that at least one nucleo> id from the - · - Group guanosine. Adenosine. inosine. Cytidine or I used ridin.