There are literally hundreds of different refill inks available for your printer. The problem is that you never know what you are actually buying and if there is any risk to the parts inside your printer, or to your health for that matter. Quality varies greatly with the majority of inks being pretty average quality imports from Asia.
Why are Asian inks generally low quality and why have they flooded the market?
To understand why, you need to understand the Asian market. The Asian market is over 4 billion people who generally have a much lower income than the western world. To sell in this market you need to produce the product as cheaply as possible so it can be sold at a price the market can afford. So when you make an ink as cheap as possible you use the cheapest dyes, carrier fluids and additives.
A number of costly manufacturing steps and quality control processes are required to produce high quality inks such as charcoal filtration, reverse osmosis and UV light purification. By omitting or reducing these processes the production costs can be greatly reduced, however so is the quality. The end products can certainly produce a pleasing colour result (at times) but fade very quickly (up to 90% quicker according to Wilhelm Imaging), have a low shelf life, block print heads more frequently and in some cases physically damage print heads and render the printer useless. The reason they have flooded the market is generally because they are cheap and this fact can easily be exploited by the people selling them, often at over inflated pricing.
So how do you know which is which?
Unfortunately the true answer is that it is extremely difficult. Unfortunately the internet and places like Ebay are difficult to regulate and a great deal of ‘creative’ advertising is used, and in some cases blatant lies about the quality and origin of ink. The reason is obvious when you think about it, Money!!!!. Buy in a cheap import product of low quality at extremely low cost, advertise it as a high quality product and sell it at just under (or even above) the highest quality product available.
Our aim is to take the guess work out, allowing you to make a choice from a high end, medium end or lower end product based on your informed decision and budget. Our only advice is that you do need to be realistic and accept that you get what you pay for. The basic and standard products we offer have been fully tested and will not harm the print heads, but they are cheaper than the premium for a reason so don't expect the same results.
The cheaper inks will fade quicker and the colour match will not be exact. Basic and standard inks are manufactured and imported from Asia. They will evaporate at a quicker rate than premium inks and this does tend to mean more print head cleaning cycles are required if you do not use your printer daily. The premium inks we choose to recommend are the rihac brand inks which we believe to be the benchmark for quality.
What makes premium inks better?
The simplistic answer is that higher quality ingredients are used and the cooking process is better.
For a more detailed explanation we need to look at the recipe and raw materials used in dye inks and the manufacturing process. This greatly effects the functionality and overall quality of the finished ink product.
Starting with the basics, dye inks are water based. This means water is used as the primary solvent. Of course there are many other ingredients that add to the performance but water is the main component. Most people would think that water is water and that is unfortunately the basic philosophy which leads to poor quality inks. Even the worst ink manufacturer knows water needs to be purified, however it is far from being as simple as using a water softening agent and deionising. The best method is a multi-step purification process. This includes charcoal filtration, reverse osmosis and UV light purification to produce water with minimal contaminants which in turn allows for an ink product having a longer life. The continual quality control processes, such as testing for contaminants and for water conductivity, (purity testing) are costly. Ink colourants (dyes in this case) are the building blocks of inkjet inks and come in various styles and qualities and are available from a wide range of suppliers.
Our premium ink manufacturer rihac choose to use Diamond Dispersions (UK) and Cobot's (USA) to supply their colourants. Much of the research for inks centres on the dye itself and the functional characteristics it brings to the ink. Specific dyes and dye combinations require changes in other ingredients to control performance.
As with most things, premium quality dyes cost more than lower quality ones, hence some manufacturers don't use them to reduce costs. Purified dyes tend to already be pH balanced, filtered, treated by reverse osmosis and contain biocides or fungicides that prolong shelf life again these add to costs. Also dyes have differing base light fastness ratings (DIN 16519), generally the higher the rating the higher the base cost. Although this does not automatically ensure a high light fastness to the finished product it certainly makes a difference.
Co-solvents and humectants, including alcohols and glycols, are added to the ink as an additional vehicle or carrier for the colourant. They may also be used to control or limit evaporation of the ink. They also affect the ink drying rates.
When added to ink, glycols reduce evaporative tendencies. Since the print heads used in the office/desk top printers are exposed to the atmosphere even when not in use evaporation occurs. Because of this evaporation, the ink's characteristics can change slightly, including viscosity or the level of concentration of materials which in turn causes a shift in the pH levels (i.e. less water, more dye, more surfactants ec ). Humectants reduce the evaporation at the orifices and thereby reduce clogging of print heads and the requirement of cleaning cycles.
Evaporation affects viscosity (thickness) and surface tension which in turn effects how an ink will flow through the print head. If viscosity increases, ink starvation through the print head occurs leading to a reduction in print quality. This is particularly important when you deal with ink in volume such as in a CISS. The example is that a poor quality ink may print fine when first used but due to the higher evaporation rates the viscosity changes over a very short period of time resulting in print quality issues and physical blockages of the print head. Once an ink composition has been changed in this way, the print head can struggle to deliver enough ink when undertaking multiple prints. This is a common issue seen in low grade inks.
Surfactants are added to adjust the surface tension of the ink and control droplet size. If the surface tension of an ink is too high, the ink may not travel through the heads correctly. Ink droplets may be too small and the drops may not spread enough on the paper resulting in white space or banding. Sporadic printing may occur under some high use conditions. A high surface tension also may cause the ink to not or penetrate the media effectively, resulting in uneven prints and longer drying times. If the surface tension is too low it can cause excessive bleeding and wicking resulting in reduced image resolution or a print looking fuzzy.
The acidity or alkalinity of the finished ink (pH level) needs to be neutral. Too acidic or too alkaline can result in damage to the print head. Dispersions have differing pH levels and thus each colour requires a different balance of additives to create a neutral pH ink.
Since inks are water-based, biocides and fungicides are added to eliminate growth of bacteria and fungus. Again these are minimised or eliminated in low quality ink production.
Buffering agents are added to control the pH for longer-term storage, corrosion resistance and the ink flow rate. Because all ingredients and dyes have different pH levels buffering agents are used to control the overall pH.
The fixative or penetrant component facilitates the ink travelling to the paper. Once the ink is in the paper, these materials fix or hold the ink and reduce feathering or wicking. Poorly controlled, these materials can make the ink permeate the paper too quickly, causing the colour to be seen on the back of the page.
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