SPECIALTY COLORS
LANXESS offers a complete range of water-based Bayscript® dyes for inkjet printing. The products are suitable for use in office printers (desktop) as well as in large-format printers and in industrial inkjet printing. Moreover, all Bayscript® colorants can be employed advantageously for high-quality inks in the office supplies industry.
Under the special dyes product family, LANXESS offers a wide range of water-soluble specialty dyes with high purity, specified surface tension, and high color strength for the stationery products industry. Pyranine 120%, a brilliant, strongly fluorescent yellow dye, is commonly used in inks for highlighters. The range also contains water- and solvent-soluble Nigrosine dyes.
Specialty Colors product family:
- Bayscript® - water-based dyes with high purity and specified surface tension
- Special colorants - water-based dyes with high color strength
- Nigrosine - water- and solvent-based dyes
Inkjet applications include small office and home printers (SOHO), large-format printers for advertising and graphic arts prints, and high-volume industrial printers for marking, coding, and labeling. Colorants for inkjet inks have to meet stringent quality criteria. Inks may be stored in cartridges for several months before being passed through tiny, sensitive nozzles under thermal or mechanical stress in order to form droplets of a defined size and shape. Key requirements are:
- High surface tension to provide reliable droplet formation and ink flow
- Low viscosity for consistent ink flow
- Excellent filterability down to 0.2 μm filter pores
- Extremely low salt content to protect printer heads and nozzles from corrosion
- Absence of bivalent cations and heavy metals for long-term storage stability
Besides the printing process, the colorants are an essential factor for print and image durability and have to provide:
- Fastness to visible light and UV radiation
- Fastness to ozone and other oxidative air pollutants
- Fastness to humidity and mechanical abrasion
Stationery in general includes all items needed for writing. Typical applications are writing utensils for everyday use, such as fountain pens, ballpoint pens, pencils, felt-tip pens, and fineliner pens. Other items are more likely to be found in offices, such as highlighters, whiteboard markers, permanent and non-permanent markers, and stamp pads. Many quality requirements for stationery colorants are very similar to those for inkjet applications and demand similar properties and quality standards. In addition, writing utensils and stamp pads need to display special features for special ink systems, such as document-proof inks, invisible inks, and erasable inks. Specific requirements are:
- High color strength, especially for black and blue inks
- Worldwide compliance with regulations for environmentally safe products and the absence of sensitive byproducts
- High surface tension and low viscosity for consistent ink flow
