Fluorescent Nanocolorants Based on Dye-Packaging Technology for Ink Jet Application

Abstract

The emerging markets and evolving safety regulations for color ink jet printing have placed more rigorous and at times new and specific requirements on ink jet ink designs. A short list of these requirements may include: 1. Larger color gamut (clear color); 2. Archival prints with enhanced image quality; 3. Any substrate or media printing; 4. Rapid throughput (approaching engine limits); 5. All-safe properties.Colorants available today do not enable the ink design chemists and engineers to meet existing market needs much less the requirements of emerging ink jet markets. This paper provides an example of a dye-packaging technology (DPT) that addresses in-part these same topics. Two disadvantages of DPT materials relative to pigmented materials which include dye-loading and light fastness will be discussed. Both of these parameters are active areas of DPT research and will be greatly improved upon in the near future. We have developed new DPT colorants of fluorescent pigments having uniform particle size, excellent solvent resistance and satisfactory light fastness in aqueous solutions. The DPT colorants containing fluorescent dyes encapsulated within spherical, solvent resistant, polymer particles having a mean particle size below 140 nm show excellent dispersion stability.Also discussed will be the light fading stability of images made with DPT materials containing fluorescent dyes and images made with water solutions containing the same dyes. Results are quoted as color difference (ΔE) units in CIEL*a*b* color space. Four different DPT fluorescent colorants (yellow, orange, red and magenta) were studied. All investigated colorants are more photostable systems than corresponding dyes.