EP2984136A1

EP2984136A1 - Pastes containing solvent

Info

Publication number: EP2984136A1
Application number: EP14715842.2A
Authority: EP
Inventors: Rosemarie Weber; Gerd Hohner; Timo HERRLICH; Stefanie GÖRES; Anton Lukasch; Rainer Fell
Original assignee: Clariant International Ltd
Current assignee: Clariant International Ltd
Priority date: 2013-04-12
Filing date: 2014-04-04
Publication date: 2016-02-17
Also published as: ZA201506451B; JP2016514758A; MX2015014333A; WO2014166614A1; DE102013006347A1; KR20150143709A; CL2015003010A1; BR112015024619A2; SG11201508335UA; US20160060463A1; CN105102528A

Abstract

The invention relates to paste preparations containing 0.5-30% w/w chemically unmodified rice bran wax, - 0.5-30% w/w paraffin wax, selected from the group of macrocrystalline and microcrystalline paraffins and Fischer-Tropsch paraffins, - optionally up to a maximum of 10% w/w polyethylene wax, - optionally up to a maximum of 10% w/w native or chemically modified recent or fossil vegetable waxes and - organic solvents to make up to 100% w/w.

Description

Solvent-containing pastes

The invention relates to paste-type solvent-containing wax preparations having improved gloss and improved retention values. It further relates to a process for the preparation of such preparations and their use for the care of shoes, floor coverings, car bodies and leather.

Waxes are widely used as a formulation component for the preparation of solvent-containing pastes for use, for example, in floor, car and shoe care (see Ullmann's Encyclopedia of Industrial Chemistry, 5th ed., Vol. A 28, pages 108, 153, 156, Weinheim 1996). Wax pastes are created by cooling hot wax solutions in organic solvents. The

Paste form allows easy application of waxes: After

By mechanically spreading the paste on the surface to be treated, the solvent evaporates leaving behind a polishable protective, nourishing or otherwise effective wax film.

As wax components for the formulation of suitable pastes nonpolar and / or polar waxes of natural, semi-synthetic or even fully synthetic provenance are used.

Significant importance as paste waxes have long been chemically modified montan waxes. Starting product here is so-called. Rohmontanwachs, which is obtained by solvent extraction from waxy lignite and including the esters of long-chain aliphatic carboxylic acids with

long-chain aliphatic alcohols is constructed. Unmodified (so-called native) raw montan wax is not suitable for direct use in pastes because of its dark color and its content of resinous accompanying substances. The chemical refining of the raw wax happens by treatment with

Chromic acid. First, the unwanted components are oxidatively destroyed, in parallel, it comes to a substantial, gradual

ongoing change in the chemical nature of the wax, beginning with the hydrolysis of the esters, with a decomposition into carboxylic acids and higher Alcohols take place. The latter are then oxidized to carboxylic acids, so that a total of degradation of long-chain ester to shorter chain

Carboxylic acid molecules takes place. These in turn are converted into wax esters or soaps in subsequent synthesis steps, with which good quality pastes can be formulated. One speaks therefore also of

semi-synthetic waxes.

In the Japanese patent application JP 36005526 the production of solvent-containing polish masses is described in which a chemically

modified, also as partially synthetic to be regarded wax on the

Basis of rice bran wax (hereinafter rice wax) is included. The modification is then a prerequisite for the application technology

Usability of the wax and is carried out by oxidation of crude rice wax with chromium trioxide or chromic acid salts in the presence of sulfuric acid and optionally subsequent esterification and / or saponification of the acid groups formed thereby. In principle, this process is identical to that of the chemical refining of the raw montan wax described above.

Unmodified rice wax is not suitable according to the teaching of JP 36005526 as an active substance in paste formulations. The modification process is complicated and requires the handling of toxic, environmentally hazardous, problematic to produce or to be disposed of substances.

The category of chemically unaltered (native) waxes of natural origin, as far as they are concerned with pastes, includes, on the one hand, certain non-polar paraffin waxes, the so-called macro- or microcrystalline paraffins, which are obtained as non-volatile fractions in the refining of fossil crude oil, and on the other hand some naturally occurring vegetable waxes, which have a polar character due to their oxygenate content. In particular carnauba wax, which is formed on the leaves of the carnauba palm, which is native to South America, as a protective layer against dehydration, should be mentioned here. It is harvested by manual tapping or boiling of the leaves and, after several purification steps, is marketed for various uses without significant chemical change. Also among the class of native plant waxes which find widespread use for paste wax formulations is candelilla wax, which is deposited on the stems and leaves of certain species of Euphorbia and Pedilanthus species found in American drylands and recovered therefrom by heating and melting.

Carnauba wax, in particular, has historically considerable economic importance as a constituent of pastes, but, like candelilla wax, does not meet all quality requirements.

In the case of the mentioned synthetic waxes are usually nonpolar polyolefin, in particular polyethylene waxes or Fischer-Tropsch paraffins. Fischer-Tropsch waxes are produced catalytically from synthesis gas. They are structurally similar to the polyethylene waxes, but differ from them by lower average molecular weights, narrower ones

Molecular weight distributions and lower melt viscosities.

An important quality-determining property of ready-to-use pastes is the so-called solvent retention. This is a measure of the rate at which the solvent contained in the recipe mixture evaporates. The lower the evaporation loss, that is, the better the retention value, the more stable the paste is and the lower the tendency to dry on storage. High demands on stability are naturally made, especially in hot countries or regions. Especially in Central and South America, paste compositions for shoe care traditionally play an important role. For the quantitative determination of the retention value, the weight loss of a defined dimensioned sample is measured after storage under defined conditions.

In terms of application, it is important for paste preparations, as far as they are used in the area of care, to have the surface gloss obtainable after application on the substrate and subsequent polishing ("gloss release") Quantitative recording is provided by standardized preparation and measurement methods.

In order to optimally match the variety of usage requirements, pastes based on empirical principles are basically made up of several different types of wax. As a rule, both polar and nonpolar waxes of natural origin as well as synthetic or semi-synthetic waxes are used simultaneously. Rice wax, according to Ullmann's Encyclopedia of Industrial Chemistry, 5th ed. 1996, Vol. A28, pages 117-118, belongs to a group of recent waxes which have hitherto been accorded only local significance or merely academic interest. The use of native rice wax in cosmetics (EP B1 1343454, see Bräutigam, Lexikon der kosmetischen Rohstoffe, Norderstedt 2010, page 77) was described as a processing aid in plastics

(JP 10007862, JP 60011553, JP 49090739, JP 60011553) and in printing inks and electrophotographic toners (JP 2010020304).

Contrary to the aforementioned findings representing the prior art, in particular contrary to the doctrine to be deduced from JP 36005526, it has now surprisingly been found that rice wax without previous chemical change excellently supports the

Making pastes is suitable and that it is in terms of quality criteria even superior to the usually used for this use watch. Specifically, by co-formulation of rice wax pastes with superior retention and high gloss levels can be achieved. This opens up new application potential for a renewable resource available in considerable quantities as a forced attack. The invention therefore relates to paste-like preparations with high gloss levels and low evaporation losses (high retention values), containing 0.5-30% by weight of chemically unmodified rice bran wax, 0.5-30% by weight of paraffin wax selected from the groups of macro- and microcrystalline paraffins and Fischer-Tropsch paraffins, optionally up to a maximum of 10% by weight. % Polyethylene wax,

optionally up to at most 10% by weight of native or chemically modified

Plant waxes as well

organic solvents in addition to 100 wt .-%.

Further objects of the invention are a process for the preparation of such pasty preparations and their use for soil care and for the care of car bodies and of leather.

Rice wax is a by-product of the processing of paddy rice (oryza sativa). After threshing the ripe rice plants, the lids adhering to the grains were removed and other lumpy components were separated along with other impurities in the rice mill, the rice grains still contain the seedling and are surrounded by the so-called. Seedling and silver skin are removed in a further processing step by grinding and provide in addition to the ground rice, the rice bran. This contains lipid components, which are predominantly made up of fatty oils and, to a lesser extent, waxy components. The latter can be found in the obtained from the bran by pressing or solvent extraction oil, from which they are due to their poor solubility at low temperatures, for. B. isolated by freezing. Rice wax consists mainly of esters of long-chain saturated unbranched fatty acids with long-chain unbranched aliphatic alcohols. In the acid part, beehive and

Lignoceric acid with chain length C22 and _C24 and in the alcohol portion of the

Chain lengths C30, C32 and _C34 . As rice wax in the sense of the invention, waxy components obtained from rice bran by any separation process can be used. Preference is given from rice bran oil in a known manner, for. B. by freezing or extraction, isolated wax components. These can be as such or after mechanical or physical cleaning, for. B. by treatment with bleaching earths and / or with activated carbon and / or after bleaching by means

Hydrogen peroxide can be used to make the pastes. It is also possible for each of the aforementioned processing stages in addition to one

Subjecting fractionation by known methods and further processing a selection from the fractions obtained in accordance with the invention. As fractionation method, z. B. an extractive separation with organic solvents such. For example, ethanol isopropanol, acetone, aliphatic open-chain or alicyclic hydrocarbons such as hexane or cyclohexane or mixtures thereof in question, wherein the starting wax about in soft and hard wax fractions, z. As those with flow hardness above and below 250 bar, can be separated. The determination of flow hardening is carried out according to

"Standard Methods" M-IV 2 (75) and M-III 13 (75) of the German Society for Fat Chemistry.

Rice waxes suitable according to the invention have acid numbers, determined in accordance with DIN 53402, between 3 and 20 mg KOH / g, saponification values, determined according to DIN 53401, between 50 and 130 mg KOH / g, dropping points according to DIN 51801-2 between 70 and 87 ° C., melt viscosities , measured according to DIN 51562 at 90 ° C with a rotational viscometer between 5 and 30 mPa.s and flow hardening between 150 and 400 bar.

According to the rice wax is not chemically modified. By chemical modification is meant here measures in which the chemical structure of the native wax fundamentally, z. B. in the sense of a far-reaching

Saponification or other chemical transformation is changed, as happens in the case of oxidation with chromic acid. In contrast, the bleaching with hydrogen peroxide means no chemical modification of the wax in the context of the invention, since only discoloring impurities and secondary constituents are eliminated without the actual wax structure being changed. Rice wax is contained in the paste-like preparation in proportions by weight of between 0.5 and 30%, preferably between 3 and 20%, particularly preferably between 5 and 15%. The paraffin waxes which can be used according to the invention are macro- or microcrystalline paraffins from the processing of fossil crude oil or Fischer-Tropsch paraffins. Macrocrystalline paraffins are obtained from the vacuum distillate fractions of the crude oil. They consist predominantly of n-paraffins. Microcrystalline paraffins originate from the residues of the

Vacuum distillation and the sediments of paraffinic crude oils. In addition to n- and iso-paraffins they contain considerable amounts of naphthenic

Hydrocarbon components. Information on the extraction and the characteristics of macro- and microcrystalline paraffin waxes and examples of these can be found in Ullmann's Encyclopedia of Industrial Chemistry, 5th ed., Vol. A 28,

Weinheim 1996 in chapters 4.2 and 4.3.

Fischer-Tropsch paraffins are produced catalytically from synthesis gas. They structurally resemble the polyethylene waxes, but differ from them by lower average molecular weights, narrower molecular weight distributions and lower melt viscosities (see Ullmann's Encyclopedia of Industrial Chemistry, 5th ed., Vol. A 28, Weinheim 1996, Chapter 5).

Paraffin waxes and / or Fischer-Tropsch waxes are contained in the paste-like preparation according to the invention in proportions by weight of between 0.5 and 30%, preferably between 3 and 20%, particularly preferably between 5 and 17%.

Polyethylene waxes are formed by ethylene polymerization, which under both radical conditions at high pressures and temperatures or with metal-containing catalysts under relatively milder pressure and

Temperature conditions can be done. In the latter case, ethylene is either polymerized in pure form to largely unbranched highly crystalline chain structures or it is by copolymerization of ethylene with

longer-chain olefinic monomers branched and therefore lower crystalline Obtained polymer structures. Another method for obtaining

Polyethylene wax is the thermal degradation of polyethylene plastic under inert conditions. For further details cf. Ullmann's Encyclopedia of Industrial Chemistry, 5th Ed., Vol. A 28, Weinheim 1996, Chapter 6.1.1. (High-pressure polyethylene waxes), Chap. 6.1.3. (Polyolefin waxes by Ziegler-Natta

Polymerization) and Chap. 6.1.4. (Polyolefin waxes by thermal degradation). The preparation according to the invention contains up to 10% by weight, preferably up to 5% by weight, of polyethylene wax. As recent or fossil plant waxes, native or chemical

modified form for optimizing the paste properties may additionally be included in the preparation come z. Carnauba wax,

Candelilla wax, sugarcane wax or montan wax in question. such

Components may be present individually or in any desired mixture in proportions of up to 10% by weight, preferably up to 5% by weight.

As organic solvents are usually liquid hydrocarbons such. B. aromatics or aromatic-free gasolines (eg., "White spirit") or

Used turpentine oil.

Examples:

The acid numbers were according to DIN 53402, the saponification numbers according to DIN

53401, the dropping points according to DIN 51801-2, the flow hardening according to

Preparation of the pastes:

The wax components were prepared according to the tab

Weigh quantities (each in g) into a beaker and mix together

melted. In the approximately 120 ° C hot melt, the specified amount of white spirit was stirred, which had been preheated to about 40 ° C. The mixture was further heated with stirring until the waxes were clearly dissolved. The solution was brought to a temperature of 2 ° above the solidification point of the melt of the wax mixture (determination of the solidification point according to DIN ISO 2207). With the solution so tempered was a pre-cooled to 10 ° C shoe cream tin can (diameter 6.2 cm, height 1, 3 cm) filled to the brim. The filled can was allowed to cool in the refrigerator for 15 minutes at 10 ° C.

Determination of evaporation loss:

The can stored for 15 minutes was weighed (initial weight A) and kept open at 23 ° C. for 7 days. Then the can was weighed again

(Final weight E). The evaporation loss was calculated from the difference A-E, based on the amount of solvent initially contained in the potted sample and expressed in wt%.

Determination of gloss:

On black linoleum 5 rectangular fields were marked with the dimension 5 x 8 cm, on each rectangle each 16 mg of the paste prepared as above was evenly rubbed with the finger. After 20 minutes of drying time, it was polished with a soft brush (200 brush strokes). Subsequently, a gloss measurement was carried out in each field (BYK gardner micro Trigloss measuring device, measuring angle 60 °) and the average was formed from the 5 measured values.

Determination of the oil content:

As a measure of the oil content, the acetone soluble portion of each

Rice waxing determined at room temperature. For this purpose, 2 g of ground crude montan wax are completely dissolved in a 50 ml volumetric flask with 15 ml of hot toluene and then filled with acetone at room temperature to 50 ml mark (calibration mark), shaken and stored for 2 h at 0 ° C. Then, if necessary, again with acetone (0 ° C) to the 50 ml mark missing solvent supplemented and then filtered the suspension. Both fractions are concentrated, dried and balanced. The oil content correlates according to this method with the percentage by mass of the dissolved acetone fraction.

Rice wax type 1 was fractionated with isopropanol into a hard wax fraction and a wax wax fraction. To this end, 100 g of rice wax type 1 were dissolved in 700 g of isopropanol under reflux (82 ° C.) and then cooled to 70 ° C. The resulting suspension is filtered after 1 h at 70 ° C. The solution is concentrated and together with the filter cake in the

Vacuum drying oven dried at 60 ° C / 50 mbar for 8 h. A hard wax fraction (58.0 g, rice wax type 5) and a soft wax fraction (40.2 g, rice wax type 6) are obtained (see Table 1).

Table 1: Raw materials used

chemically refined

Montan wax,

Licowax ^® 0 12.0 1 10.0 102 - - esterified and

partly saponified

chemically refined

Licowax ^® E montan wax, 18.0 145.0 82 - - esterified

Carnauba T4 carnauba wax 7.0 83.0 84 - -

Licowax ^® PE

Polyethylene wax 0,0 0,0 123 - - 520

Ozokerite 2089 microcryst. Paraffin 0 0 57 - -

Block paraffin

macro crystalline. Paraffin 0 0 57 - - 5603

The solvent used was white spirit.

Sources:

Licowax ^® grades: Clariant (Germany) GmbH

Carnauba T4, Ozokerite: Ter Hell & Co. GmbH Block paraffin 5603: Sasol Wax.

The examples in Table 2 show that in a practice-standard paste formulation based on semi-synthetic montan wax or carnauba wax in their replacement against rice wax improves the gloss values, but in particular the evaporation losses are reduced.

Table 2: exemplary embodiments

Claims

claims

1. Paste-like preparations containing

0.5-30% by weight of chemically unmodified rice bran wax,

0.5-30% by weight paraffin wax selected from the groups of the macro- and microcrystalline paraffins and the Fischer-Tropsch paraffins, optionally up to at most 10% by weight polyethylene wax,

optionally up to at most 10% by weight of native or chemically modified recent or fossil plant waxes and

organic solvents in addition to 100 wt .-%.

2. Paste-like preparations according to claim 1, characterized in that the chemically unmodified rice bran wax has been treated with hydrogen peroxide and / or bleaching earth and / or activated carbon.

3. A process for the preparation of paste-like preparations according to one or more of the preceding claims by mixing the

Components at elevated temperature and cooling the mixture.

4. Use of paste-like preparations according to one or more of the preceding claims for soil care.

5. Use of paste-like preparations according to one or more of the preceding claims for the care of car bodies.

6. Use of pasty preparations according to one or more of the preceding claims for the care of leather.

7. Use of pasty preparations according to one or more of the preceding claims for shoe care.