Now let me take the readers to a different topic in Water Based Paints known as BASES. For quite some time tinted/coloured water based paints were made as direct shades, mean the shade itself is made in the productionline, whereby it is packed and kept in various shades and packings depending on market requirements. This always used to lead accumulation of shades in unwanted packing which normally do not move in the market. Like this stocks do pile up with the Dealers and also at manufacturers godown. This leads to disposal of such unwanted stocks, sometimes at throwaway prices. Instead of incurring reverse transport expenses manufacturers tend to make it as distress sale by selling good quality materials at throw away prices. Ultimately every year the loss on sale of paint in unwanted packing and shades keep increasing, adding loss to the manufacturers.
In order to minimise such losses, cut down inventory and improve upon the tinting strength White Bases without colour were introduced in Indian Paint market in late 80's. Bases are meant to be post tinted, ie: after manufacturing the bases are tinted mostly at the Dealers' premises using a tinting machine. It is impossible for paint shops/manufacturers to stock every colour of paint. However, a paint store can mix any paint colour for a customer while he waits, thanks to paint bases. An endless spectrum of paint colours are created by mixing specific quantities of one or more Colourants with a tintable paint base. A tintable paint base is used to form the foundation for a particular colour. Assorted paint bases typically offered by paint manufacturers include: white, pastel, light, medium, deep and clear. Clear bases are used to create darker colours, while white bases make the lightest colours. Paints are generally available as white, tint and deep and accent bases that can be tinted to various shades and depths by the use of liquid colorants. The level of opaque pigment (in most cases titanium dioxide) is varied to balance the value (degree of darkness or lightness) of the colour.
Some fundamentals about bases
A tintable paint base is used to form the foundation for a particular colour. Assorted paint bases typically offered by paint manufacturers include: white, pastel, light, medium, deep and clear. Clear bases are used to create darker colours, while white bases make the lightest colours. A light base creates a lighter colour than a medium base. Paint base determines how resistant paint is to dirt and stains, as well as its durability under intense scrubbing.
All tintable base paints contain titanium dioxide in various quantities, except clear base, which does not have any. Titanium dioxide determines how effectively paint conceals the previous surface colour. Tintable base paints containing larger amounts of titanium dioxide hide surfaces better than bases with smaller quantities. While light bases are more opaque than medium bases, white bases have the most titanium dioxide with the most complete coverage. Dark paints created from bases with little or no titanium dioxide provide less opaque coverage.
One or more colorants added to a tintable base create a specific colour. Saturated colorants mixed into a white base form a lighter version, or tint, of the pure saturated colorant. For example, if a burnt-umber colorant is added to a white base, the result would likely be a very light beige colour. A light base produces slightly darker beige and a medium base results in an even darker beige colour. Colorants also determine how much a colour will fade. A light base will typically provide more opaque coverage than a medium base. However, a medium base can create a deeper colour than a light base. Additives, such as mildewcides to inhibit mold growth and thickeners to help guard against paint drips and spatters, are often incorporated into base paints. More expensive paints often contain the highest level of quality ingredients.
Now let me give the readers more insight about bases. Bases are generally classified as, White, Base I, II, III and clear base/Dark base. Usually white is never used for tinting as the percentage of Titanium Dioxide in it is higher than the bases, hence has the tendency to take more tinter to tint, there by taking the cost of tinting very high. But white is first formulated to categorise the type of paint as the percentage of Rutile and Emulsion will determine the type/class of paint, say, low, medium, high and premium grade paints. So it is very much essential for the Formulator to decide the category of Paint, formulate the white and then formulate the bases. Now let us go into the differentiation of various bases.The terms pastel base and medium base refer to a paints ability to be tinted because of the amount of white pigment or Rutile and other opacifying pigments added in it to make it opaque. The majority of house paints/architectural paints used, for example, tend to be lighter colours. These colours have a fair amount of white pigment in them to give it that light tone but also for coverage. If required to paint a room or a feature wall with a really dark blue or red one need to paint with medium or deep/dark base. A white base paint (one with lots of white pigment/Rutile in it intended for lighter colours) has a limit to how dark it can be tinted — after reaching that limit, the strength of the paint and ability to dry is affected. It is impossible to tint a white based paint to be a dark blue or red, in view of high Rutile and opaque pigments and extenders.
A medium based paint can be used to achieve paint colour that is too dark for a white based paint — it has less white pigment added so that the desired level of colour saturation can be reached but enough to maintain a reasonable ability to hide underlying coats of paint. A deep based paint has even less if any white pigment/Rutile and white extenders and can be tinted to match very dark, rich, vibrant colours. The problem with these paints is that sometimes their ability to cover underlying colours can be terrible. If one try and paint a white wall with a dark red, it could take several coats. It can also end up looking very patchy where brushwork overlaps rolled areas, and even lines from paint rollers can be very noticeable. For these dark colours, A half tinted primer is needed to give a solid base coat and the deep base or medium base paint is rolled over top to get the desired depth of colour.
When one buys paint, they have to mix in colours to get the correct tint. If a shade of dark blue is required, then they use a can of deep base to mix in the colours. As long as both paints are water based, you can mix them.
- The different bases are different because if one wants a really deep colour, he/she have to start with a base that has less white in it. If there is too much white in the base, one cannot get a very deep colour when tinters are mixed.
- A pastel or lighter colour can have more white in the base. One needs to check what the requirements are for the paint that is required. The bases are used for mixed paint, like a custom colour is needed. If one finds a white or standard colour that is ready-made and can be purchased without mixing.
- Typically deep base and medium base are used as part of mixing in the colours. Some of the assorted paint bases offered by paint manufacturers include: white, pastel, light, medium, deep and clear. Medium base creates a colour between light and dark while Deep base produces a darker colour of paint.
A medium based paint can be used to achieve paint colour that is too dark for a white based paint, it has less white pigment added so that the desired level of colour saturation can be reached but enough to maintain a reasonable ability to hide underlying coats of paint. One needs to check what the requirements are for the paint that you want. The bases are used for mixed paint, like if you want a custom colour. If you find a white or standard colour that is ready-made and can be purchased without mixing.
- https://www.hunker.com/12003255/light-base-paint-color-vs-medium-base-paint To be continued