Why are touchless washing products sold in different concentrations?
This is first of all an economic question. The point is that, per litre of working solution, a highly concentrated product takes up less space and has less weight, which makes it possible to save on transport and storage. But the higher the concentration of the detergent, the more expensive it is to produce per litre of ready solution. In each particular case, therefore, one has to calculate which product will turn out to be more cost-effective in the end. It is worth noting that the production of highly concentrated detergents (with a dilution ratio of 1:70 and above) requires not only high-quality raw materials but also a high standard of manufacturing. The presence of such products in a manufacturer’s range may therefore speak of its reliability and high competence.
The packaging gives a dilution range, for example from 1:40 to 1:60 or from 1:70 to 1:100, and not one specific value. What does this depend on?
The dilution ratio of one and the same concentrate may differ depending on the hardness of the water used at the car wash. The harder the water, the higher the concentration of the detergent must be. The manufacturer always works from some average or slightly raised water hardness value, and in each particular case the concentration has to be selected experimentally. It should be taken into account that the hardness of water from one and the same source can be constant only if that source is artesian. If the source is a surface one, and the overwhelming majority are, then the hardness of the water in it varies with the season: in winter it is higher, in summer lower. If too little concentrate is added to hard water, the pH value of the washing solution will be too low and the washing properties of the solution will be poor. An excess of concentrate will raise the pH and improve the washing properties, but too high a concentration of detergent, firstly, leads to overconsumption and increases the cost of washing the vehicle. And secondly, at excessively high concentrations (pH above 12.5) the solution becomes too aggressive towards the top layer of the paintwork, making it cloudy, accelerates the corrosion of parts made of non-ferrous metals, of aluminium in particular, and has a destructive effect on rubber seals. We therefore recommend monitoring water hardness regularly and selecting the dilution ratio of the concentrate so that the pH value stays within the range 9.5 – 11.5. In winter a solution with a pH value closer to the upper limit is usually used, since there is more contamination and it is heavier.
What is the difference between single-phase and two-phase touchless washing products?
Single-phase and two-phase detergents are also called one- or two-component, and they differ in that two-phase concentrates separate into two phases during storage because of their limited ability to mix. Manufacturers usually colour these components in different colours so that it is easy to determine that the concentrate has separated. If it has separated, it must be stirred thoroughly before use. The washing properties of two-phase products are higher than those of single-phase ones. But single-phase ones are more convenient in work: they do not have to be stirred before dilution. That is precisely why single-phase products have become more widespread.
How can a good touchless washing product be told from a poor one by its appearance?
It is impossible to determine a good touchless washing product unambiguously from its appearance. However, some signs can point quite definitely to a concentrate of low quality. A quality product must not contain any suspended matter, and there must be no rust, sand, shavings or other debris in the canister. During long storage or when the product is cooled to +4°C no clouding or sediment must occur. After freezing and subsequent thawing the product must retain its properties: it must not change colour, it must remain homogeneous, and so on.
Does the appearance of the foam affect the quality of the wash? Do the washing properties of coloured and white foam differ?
A touchless washing product must foam well, and the foam must stay on the surface for several minutes to let the active substances work. Nevertheless, a high stable foam that produces an excellent visual effect may only mean that the detergent contains a lot of foaming agents and foam stabilisers, urea for example, and this does not always indicate high washing properties of the solution. It may turn out that foam which collapses after three or four minutes and runs off the body together with the dirt is more effective than foam that pretends to be fluffy freshly fallen snow. As for coloured foams, this is a purely marketing move. Such foams may make a more favourable impression on customers because of their unusual look, so some manufacturers simply add special colourants to them. These colourants give no effect other than the visual one.
Why must the solution be rinsed off the surface of the vehicle before it dries? Why is it not recommended to wash vehicles in the sun and in a draught? Why must the body be cooled first if it has heated up to more than 30°C?
The point is that on drying the detergent may leave streaks that are hard to wash off, or a whitish deposit of sodium silicate, which can only be removed with a mild abrasive. Washing a vehicle in direct sunlight or in a draught is not recommended precisely because the washing solution dries very quickly. If you simply cover the body with foam and rinse it off at once, the foam will not work, and if you try to wait a few minutes, the detergent will simply dry on the body. For the same reason it is not recommended to wash bodies strongly heated by the sun without cooling them first.
There is an opinion that gel shampoos have a higher concentration than liquid ones. How true is this?
The viscosity of a shampoo is in no way connected with its concentration. Both highly concentrated and low-concentration shampoos may be either liquid or gel-like. It should be noted that gel shampoos cannot be used in dosing systems (pulse pumps, dosatrons, self-service washes). Gel shampoos are also less convenient in work; in particular, they are harder to dilute to the required concentration and need more thorough stirring.
Which shampoos should be used in dosing systems?
Any liquid shampoos may be used in dosing systems if several conditions are observed.
Firstly, the shampoos must be of stable quality, their properties must not differ from batch to batch.
Secondly, before deciding to use a particular shampoo, it should be checked for compatibility with the water you intend to use. Dilute the shampoo with water to the required concentration and keep the solution for three days. If the solution does not crystallise, the shampoo and the water are compatible.
Thirdly, water hardness should be monitored regularly and corrections made to the concentration of the ready solution.
What is a winter shampoo?
Recently a shampoo positioned as a winter one has begun to appear on the market. Its difference from ordinary shampoos is that it copes better with the removal of de-icing agents, which is especially important in winter.