Enhanced Stability and Performance Cosmetic Ink Composition

This inventive concept presents a cosmetic ink composition with improved storage modulus and reduced settling over time, enabling high-frequency printing via thermal and/or piezo inkjet printheads while maintaining long-term stability.

The original patent disclosed a cosmetic ink composition suitable for high-frequency printing, but it had limitations related to settling and storage modulus. The new inventive concept addresses these limitations by introducing surface modification, adjusting the ratio of (meth)acrylic acid homopolymer or salt to rheology modifier, and treating the particulate material with a surface active agent.

The enhanced cosmetic ink composition comprises a particulate material with a Particle Size Distribution D50 of about 100 nm to about 2,000 nm, exhibiting improved storage modulus and reduced settling over time. The particulate material may have a surface modification to enhance its compatibility with the (meth)acrylic acid homopolymer or salt thereof. The composition may also include a rheology modifier, where the ratio of (meth)acrylic acid homopolymer or salt to rheology modifier is adjusted to achieve a target storage modulus. Additionally, the particulate material can be treated with a surface active agent to reduce its tendency to agglomerate. This inventive concept can be used in a system for inkjet printing, comprising a cosmetic ink composition and a printhead configured to eject the composition at a frequency of at least 10 kHz.

The new claims introduce novel features such as surface modification, ratio adjustment, and surface active agent treatment, which provide a non-obvious solution to the original patent's limitations. These features improve the stability and performance of the cosmetic ink composition, enabling high-frequency printing while maintaining long-term stability.

Alternative embodiments of this inventive concept may include varying the type and amount of particulate material, using different surface modifications or surface active agents, or adjusting the ratio of (meth)acrylic acid homopolymer or salt to rheology modifier. Additionally, the inventive concept can be applied to other printing applications, such as 3D printing or digital printing.

The enhanced cosmetic ink composition has significant commercial potential in the inkjet printing industry, particularly in the fields of beauty, cosmetics, and packaging. The ability to print high-quality, stable images at high frequencies enables new business opportunities and revenue streams for companies operating in these markets.