What Is Highly Dispersible Polyvinyl Alcohol (PVOH) for Thermal Paper Developers? Introducing a Product Compatible with Phenol-Free Developers

Thermal paper is a specialty paper that changes color when heated and is widely used for receipts, labels, and other applications. At the heart of this mechanism is the developer contained in the color-forming layer. When heated, the developer reacts chemically with a leuco dye to produce color.
For more information on how thermal paper develops color, please see this page.

Good dispersion is essential for maximizing developer performance. PVOH is used as both a dispersant and binder for developers, supporting thermal paper performance by improving the dispersion of leuco dyes and developers.

When used as a dispersant and binder for thermal paper developers, PVOH offers the following characteristics:

1. 　Uniform dispersion: PVOH’s excellent dispersibility enables developers to be distributed evenly, helping produce consistent color across the entire thermal paper surface.

2.　Dispersion stability: PVOH is used to improve the dispersion stability of leuco dyes and developers.

3.　Binding strength: PVOH can function as a binder in thermal paper formulations, helping securely anchor developers within the coating layer

Mitsubishi Chemical’s specially modified PVOH GOHSENX^TM L Series offers superior uniform dispersion, dispersion stability, and low-viscosity dispersion formulation compared with conventional PVOH, making it well suited for use with thermal paper developers.

GOHSENX^TM L is a specially modified PVOH supplied by Mitsubishi Chemical. It is an anionic polymer containing sulfonic acid groups in its molecular structure. Its dispersibility is described in more detail below.

1. 　Excellent dispersibility: GOHSENX^TM L performs exceptionally well as a dispersant for both organic and inorganic materials, particularly dyes and thermal paper developers. Compared with conventional PVOH, it can produce fine particles in less time at a lower addition level while also providing excellent dispersion stability. It can also help improve image resolution and maintain whiteness.

2.　High emulsifying performance: Its excellent emulsifying and protective-colloid properties make it effective as a protective colloid for emulsion polymerization. It enables the emulsion polymerization of acrylic emulsions, which is difficult with conventional PVOH, and produces stable emulsions with high adhesive strength and excellent dry-film performance.

3.　Strong adhesion: It also delivers excellent performance as an adhesive and coating agent, helping improve product quality. When used as a binder for thermal paper developers, it firmly fixes the developer in place and supports uniform color development.

4.　Stability: It improves dispersion stability and helps maintain uniform performance over extended periods.

In recent years, phenol-free products have attracted increasing attention in the thermal paper developer market. Conventional thermal paper has used phenolic compounds such as bisphenol A (BPA) and bisphenol S (BPS), but concerns have been raised about their potential effects on human health and the environment. As a result, many companies are developing phenol-free developers and working to improve the safety of thermal paper.

Benefits of Phenol-Free Developers

1.　Improved safety: Because phenol-free developers are designed to reduce impacts on human health and the environment, they can support the development of safer products and help lower potential health risks for consumers and workers.

2.　Regulatory compliance: As the use of phenolic compounds is regulated in many countries and regions, phenol-free developers can help manufacturers comply with applicable regulations.

Washington State in the United States has adopted restrictions on bisphenols, including bisphenol A (BPA) and bisphenol S (BPS), in thermal paper. The restriction applies from January 1, 2026, accelerating the transition to bisphenol-free thermal paper.

This regulatory shift is expected to further accelerate demand for phenol-free products.

GOHSENX^TM L has demonstrated excellent dispersibility with phenol-free developers in internal evaluations, showing strong applicability in this field. It is therefore an excellent dispersant option for phenol-free thermal paper applications that require both safety and performance.

The dispersibility of polyvinyl alcohol (PVOH) plays an important role in the dispersion of thermal paper developers.

Mitsubishi Chemical’s specially modified PVOH, GOHSENX^TM L, offers excellent dispersibility, protective-colloid performance, dispersion stability, and low-viscosity slurry dispersion formulation and has an extensive track record across a wide range of industrial applications.

Phenol-free developers are also an important trend in improving the safety of thermal paper. They can help reduce potential impacts on human health and the environment while supporting more sustainable product development. By enabling effective dispersion of phenol-free developers, GOHSENX^TM L Series contributes to thermal paper that combines safety with sustainability.

For more information about modified polyvinyl alcohol GOHSENX^TM, please visit this page.
For more information about the GOHSENX^TM L (Anionic PVOH L) Series, please visit this page.