micro crystalline paraffin waxes


Paraffin waxes, Other applications


Paraffin waxes, Other applications

In addition to the discussed fields of application, paraffin waxes are used in many branches of industry, such as the match industry, the rubber industry, PVC processing, precision casting of metals, manufacture of refractory ceramics, the electrical industry and building construction. Further consumers of para& waxes are the textile industry, dental profession, pencil manufacturers, pyrotechnic industry, etc.

(a) The match industry is one of the oldest consumers of paraffin waxes. Paraffin impregnation of the matches, usually made of wood, has the objective of ensuring rapid ignition of the matchwood after striking the matched. In addition, waxing improves adhesion of the matched to the matchwood and resistance to moisture. The latter is of particular importance for matches stored and used in high-moisture climates.

Previously, lower-melting micro crystalline paraffin waxes (42 to 46 “C m.p.) were preferred for match impregnation. At present higher-melting Paraffin waxes (m.p. 46 to 54 “C) are more wide-spread in use. Still higher-melting paraffin waxes could also be used, but are too expensive. The oil content of paraffin waxes for impregnation must not exceed 5 wt- %; the usual value is around 3 wt- %. Higher oil content paraffin wax leads to excessive flickering of the flame. Some match manufacturers use 1 to 2 wt- % paraffin wax in the match head, too, in addition with use Residue wax (Foots oil) in body of the match, resulting in more uniform burning.

(b) The rubber industry The rubber industry is also one of the most important paraffin wax consumers, using it for a variety of purposes. Paraffin wax, when used as an additive to rubber increases the stiffness of the product. This is of major importance in press-moulded rubber products. If the paraffin wax content in rubber exceeds 1 to 2 wt-%, it migrates to the surface and forms a continuous thin layer. This phenomenon is called efflorescence. The thin layer bends, without cracking, with the rubber products. Experience has shown that the layer of wax effectively inhibits the oxidative ageing processes accelerated by light. If it is desired to obtain low-friction surfaces, 3 to 5 wt-% paraffin wax is added to the rubber compounds. Paraffin waxes are often used with painted rubber goods to prevent decoloration. In rubber latices various paraffin waxes (I to 2 wt-%) are used as plasticize-rs to reduce toughness. Almost all types of paraffin waxes are in use in the rubber industry. In the manufacture of air tubes, macro crystalline paraffin waxes containing 2 to 5 wt- % oil are used to ease moulding and to achieve uniform surface resistance to abrasion in the Tyre. Blends of macro- and micro crystalline paraffin waxes are used in the manufacture of sealing rings for preserve jars and other types of sealing rbgs. For industrial-purpose rubber goods, e.g. hose, where requirements of color and odor are not so critical, less refined petrolatum of darker color are used.

(c) Precision casting, is a useful process for the economical manufacture of metal components and tools in small batches. Although the process is also used for components of mass greater than 100 kg, its most important field of application is with smaller components, with mass of the order of a kilogram. The process consists of the following steps: a die is made from a prototype, and paraffin wax is poured or pressed into the die. After cooling, the paraffin wax model is removed from the die, and a ceramic coating is applied onto the model. When the ceramic coating has solidified, the paraffin wax is melted and poured from the ceramic shell, which is subsequently baked in a kiln. The molten metal is usually cast into the ceramic moulds whilst the moulds are still hot. After solidification of the melt, the ceramic shell is broken to remove the casting. The most important components of casting paraffin waxes are lower-melting paraffin waxes, various natural waxes, e.g. carnauba wax, synthetic waxes, as well as higher melting fatty acids, e.g. stearic acid. Blends of around 50/50 wt-% macro crystalline paraffin wax and stearic acid are frequently used. In addition, some casting waxes contain bitumen. Studies carried out in the Hungarian Oil and Gas Research Institute demonstrated that low-contraction casting waxes can be produced from partially oxidized micro crystalline paraffin waxes and micro crystalline paraffin waxes containing wax esters.

(d) The manufacture of refractory ceramics Paraffin wax casting of ceramics is a process being increasingly used in industry, mainly for porcelain, A1,0,, MgSiO,, ZnTiO,, TiO,, ZrO, and fireclay. Other materials for which the process has been used are CaO, MgO, MgA1,0,, Sic, Mo.Si,, Si,N,, Si, TiB,, TiN, ZrB, and other high-melting compounds. Clay cannot be used as binding material for shaping, since it reduces the melting point of refractories. Instead, the ground refractories are mixed with molten paraffin wax to yield a malleable mass, which is then cast into metal moulds or moulded at pressures of several hundred bars. Injection moulding is also used for mass production. The parts solidified in the water-cooled moulds are coated with a porous embedding material and introduced into the prefiguring kiln. The temperature is slowly raised to 400-60O0C, whereupon paraffin wax diffuses out into the embedding material where it evaporates and burns away. Depending on the composition of the ceramic, prefiguring is continued to 900- 1250°C. Subsequently the embedding material is removed and final firing at high temperature follows. Slack wax melting at 50-54 “C is used to prepare the slurry for casting.

(e)The electrical industry uses large amounts of different types of paraffin waxes for insulation at ambient temperature. Obviously, paraffin waxes alone cannot be used at higher temperatures, only in blends with synthetic waxes. In addition to high relative permitting, low dielectric loss and high resistance values, important requirements for paraffin waxes to be used in the electrical industry are flexibility, ductility and low thermal expansion coefficients. Direct paraffin wax coating is frequently used for the insulation of Wires, cables, flat or irregular-shaped metal surfaces. For such purposes only micro crystalline paraffin waxes which are flexible, adhere well to metals, and have only a slightly shrinkage on cooling are usable. Paraffin wax impregnation of other insulating materials, e.g. paper, textiles, asbestos, wood, is also frequently used in order to improve their insulating properties and moisture resistance. Paraffin waxes and paraffin waxes with additives are much used for building up blocking layers, e.g. for capacitors, for cable terminals and couplings, for impregnating cable-insulation paper, for filling the space between cables and around the coupling. The zinc casings of dry cells can be sealed with paraffin wax or paraffin wax impregnated paper. This will efficiently reduce desiccation of the cell. Paraffin waxes used for insulation usually have melting points above 55 “C and oil contents below 1 wt-%. Paraffin waxes are used to reduce the viscosity of bitumen used for impregnating linen tape. For this purpose the oil content may be as high as 2 to 4 wt-%. To impregnate paper for paper-insulated capacitors, the oil content must not exceed 0.5 to 1 wt-%, and the melting point should exceed 55 “C. In roll-type cylindrical or flat capacitor elements encased in metal or paper the empty space is usually filled with paraffin wax. For paper casings, blends of higher melting micro crystalline paraffin waxes and various resins are used. The melting point of cable waxes is in the range of 55 to 65 “C. Requirements are non-stickiness and absence of components with boiling points below 180 “C


Paraffin waxes in cosmetic industries

Paraffin waxes in cosmetic industries

Paraffin waxes in cosmetics industry are using in the last century. Initially raw materials of cosmetics were vegetable or animal origin were solely used for such purposes. Only later did petroleum products make their entrance into the cosmetics industry and find general acceptance. The following petroleum products are in use for cosmetic purposes : Vaseline oil, Vaseline, macro- and micro crystalline paraffin waxes. Macro- and Micro crystalline paraffin waxes make a significant difference to the resistance to mechanical impact, hardness and softening point properties of cosmetic preparations. Micro crystalline paraffin waxes are tougher than macro crystalline waxes, they exhibit plastic flow under the effect of compression, while macro crystalline waxes have higher compression strength. Since the solvent and oil uptake capacity of micro crystalline paraffin waxes are very high, increasing oil content usually results in higher plasticity.

Vaselines are important constituents in a large sector of cosmetic products. With regard to their origin, Vaselines are natural Vaselines, so-called slack wax Vaselines or artificial Vaselines. Natural Vaselines are obtained from the distillation residues of petroleum by direct treatment with bleaching earth, or by refining with sulfuric acid and bleaching earth. Alternative processes are De-asphalting of the residue followed by bleaching, or refining with sulfuric acid and bleaching. Slack wax Vaselines are manufactured from paraffin slack waxes or petrolatum. Artificial Vaselines are blends of Vaseline oils and macro- or micro crystalline paraffin waxes. The use of Vaselines can be regarded as an indirect use of macro crystalline, and, especially intermediate and micro crystalline paraffin waxes.

(a) Solid perfumes

Paraffin waxes are used in the manufacture of fatty solid perfumes. Solid perfumes are used to scent the surface of the skin. Those having a higher alcohol content also have a refreshing effect that can be increased by menthol. The two main types of solid perfumes are fatty and alcoholic perfumes, the latter containing more than 75 wt- % alcohol.

(b) Cosmetic creams

Vaseline and Vaseline oil are main ingredient of Cosmetic creams. They are paste-like preparations used for skin care of the face and hands. The types so-called dry, semi-fatty and fatty creams. They are usually prepared on a stearate base. In addition to stearic acid derivatives they contain relatively high amounts of petroleum products (Vaseline, Vaseline oil), fatty alcohols (e.g. acetyl alcohol) and multi functional alcohols (e.g. glycerol). Fatty creams contain less water and more fatty substances, waxes, fatty alcohols and petroleum products.  In summer and winter varieties of these creams also exist: within a given formulation these varieties are prepared by changing the oil content (e.g. Vaseline oil) and the content of solid or semi-solid components (e.g. Vaseline, paraffin wax). Cleansing creams belong to the group of fatty creams. They are primarily intended for persons with sensitive skins, to cleanse the facial skin. Anhydrous cleansing creams contain higher amounts of paraffin waxes, Vaseline and Vaseline oil. Homogeneous creams can be prepared best by using micro crystalline paraffin micro crystalline, since they retain oil at the temperature of application. Cold creams belong to the fatty or semi-fatty type, depending on fat content. These are aqueous emulsions with a cooling effect on the skin. Of the petroleum products, cold creams use greater quantities of Vaseline oil and Vaseline, but lesser amounts of paraffin waxes. Semi-fatty cold creams are usually based on glycerol monostearate or diglycol stearate, with a substantially higher water content than that of the fatty creams. In contrast to fatty creams they do not leave behind an oily, fatty film on the skin. They can readily be removed from the skin with pure water.

Baby creams also contain substantial amounts of Vaseline and Vaseline oil. Their composition resembles that of cleansing creams. Sport creams belong to the semi-fatty group. They are aqueous emulsions containing substantial amounts of petroleum products.


(c) Beauty masks

The main objective of beauty masks is to relax the tissues of the face and enhance blood circulation.

(d) Protective creams for industrial workers

Protective creams are being used in many branches of industry, especially to protect the skin on the hands and arms of the workers against harm caused by various chemical and physical effects. Most of the protective creams are based on Vaseline, but some of them also contain macro crystalline paraffin waxes.

(e) Facial care and beauty products

Cosmetic preparations for facial care, e.g. to soften dry, parched lips are made of natural and synthetic waxes, fats, fatty alcohols, Vaseline and sincerer. The most important starting materials for the manufacture of lipsticks are various natural and synthetic waxes, fats, fatty alcohols, Vaselines, paraffin waxes and dyes. Mechanical strength of the lipstick is achieved by using waxes and


Micro crystalline paraffin waxes with higher melting points. Among natural waxes, bees-wax is typical of the kind used in almost all types of lipstick, owing to its plasticity. Among petroleum products, high-melting micro crystalline paraffin waxes raise the strength and softening point of the lipstick, but are rarely used in amounts exceeding 15 wt-%, because they tarnish the gloss of the surface. The use for macro crystalline paraffin waxes is limited, due to their causing a granular structure. Vaseline increases gloss and is of importance for the consistency of the product. It is, however, easily wiped off from the lips. Vaseline is usually present in concentrations of 20 to 35 wt-%. The effect of vaseline oil is very similar to that of Vaseline. In addition, it improves uniform spreading of the lipstick. Excess amounts of both Vaseline and Vaseline oil result in low-melting, soft lipsticks. The melting point of lipsticks varies between 45 and 65 “C. Lower-melting types spread better, while contours are easier to draw with the higher-melting lipsticks.This particular one is characterized by its high paraffin wax content. Face make-up is manufactured from the same raw materials as lipsticks. The main requirement is easy and uniform spreading, so that they contain higher


(f) Hair preparations

Among cosmetic preparations for hair, solid brilliantine and hair pomades utilize significant amounts of paraffin waxes and Vaseline, the higher percentages being found in the latter.



(g) Anti-perspirants

A perspiration-reducing and deodorant product containing relatively high percentages of paraffin wax and Vaseline