| Virtually all types of promotional pens carry an | | | | their presence is to make the ink into a printing |
| advertising message or promotional logo but the | | | | consistency and not to achieve adhesion. Generally, |
| printing inks used on them can vary enormously, | | | | catalytic inks have a high-build when printed because |
| depending upon the material the pen is made from | | | | they have a high solids content. |
| and the printing process being utilised. Here, you will | | | | U.V. Inks: These ultraviolet curing inks, are being |
| find an overview of the printing inks in most popular | | | | increasingly used in the screen-printing industry for |
| use. | | | | printing promotional pens and promotional items in |
| Solvent Evaporation Inks: These are without doubt | | | | general. They are similar to catalytic inks in that they |
| the most common inks used on plastic promotional | | | | require an additive to be added to act as a catalyst |
| pens. The term does not apply to any particular ink | | | | to initiate cross-linking. This catalyst is referred to as |
| but is a large family of ink systems formulated for | | | | photo initiator. Their main advantage is that they are |
| their intended purpose. Solvent evaporation ink | | | | quite easy to print because they do not dry in the |
| systems are optimised for printing on paper & board, | | | | screen. This is referred to as good screen stability |
| touch control panels, overhead projection slides, as | | | | and it normally means downtime is reduced. Other |
| well as for promotional pens and many other | | | | benefits of UV curing inks are, finer detail can be |
| promotional items. Although their chemistry is diverse, | | | | printed, higher gloss levels and better print definition. |
| the mechanism for drying is the same; through the | | | | The disadvantages are that they can be quite |
| evaporation of solvents within the ink. These ink | | | | translucent compared to other ink systems, they |
| systems can be made up of sixty percent solvent | | | | have a high build, they are quite brittle, ink-adhesion is |
| which has to evaporate after the ink is printed. | | | | more temperamental, high degree of brittleness, they |
| Therefore, it follows that the volume of a solvent | | | | produce ozone when cured and a protective gloves |
| evaporation inks decreases by that amount when | | | | must be worn to handle them. Normally these inks |
| dried and that is why these inks are regarded as | | | | are used to print promotional pens made of ABS or |
| low-build or low-feel inks. These inks when printed on | | | | styrene, but it is also now occasionally used for metal |
| promotional pens achieve a high level of adhesion | | | | pens and pens made from polypropylene. |
| because the active solvents melt the plastic. This | | | | Long Oil or Oxidation Inks: These inks are hardly ever |
| results in a strong bond being created between the | | | | used these days but are sometimes used for printing |
| ink and the pen substrate and normally this cannot be | | | | on materials when other systems will not provide |
| scratched off. Typically, plastic promotional pens are | | | | adequate adhesion. They resemble paint in their |
| made from ABS, styrene or acrylic and solvent | | | | drying characteristics in that they require the |
| evaporation inks are perfectly suited to printing these | | | | presence of oxygen to dry properly and they take |
| polymers. | | | | days to become completely hard. They are |
| Catalyst Inks: These inks are used on promotional | | | | characterised by high levels of gloss and have a high |
| pens when the material the pen is made from is | | | | build. Occasionally they will be used on wooden |
| impervious to solvent attack. In this case, the | | | | promotional pens and metal promotional pens. |
| bonding mechanism relies on the ink sticking to the | | | | In general, all promotional pens must be thoroughly |
| pen like glue and there is not chemical bonding | | | | cleaned before they are printed to ensure that |
| between the ink and the substrate, unlike solvent | | | | adhesion is not compromised. To an ink |
| evaporation inks. Again, the term 'catalytic' refers to | | | | manufacturer, the surface of a pen is regarded as a |
| a large family of inks optimised for different materials | | | | hostile environment for a printing ink because of the |
| and applications. Within that family will be inks to print | | | | level of handling and contamination it is subjected to. |
| polypropylene, metal, stove enamel, nylon, glass, | | | | Therefore, virtually all inks are highly technical in |
| wood etc. They all have one thing in common, | | | | formulation and often only launched after years of |
| however, and that is their curing mechanism relies on | | | | development. Because of this, they tend to be very |
| the polymer chains cross linking with each other | | | | expensive, although the amount required to print |
| which is initiated by the catalyst or hardener that is | | | | each promotional pen is minimal and therefore is a |
| added to these inks. Although these inks carry | | | | minor cost. |
| solvents, they are not usually aggressive because | | | | |