Color-Changing Gas Leak Detector Formula

I have an existing bubble-forming base (≈ 85-90 % distilled water, 3-5 % non-ionic surfactant, 5-10 % glycerin, 1-3 % propylene glycol plus a trace dye) and now need it engineered into a reliable spray that turns vivid green the moment it contacts natural gas, yet still produces stable, highly visible bubbles. The solution must work in both indoor and outdoor settings without leaving permanent stains or hazardous residues.

Here is what I need from you: • Refine the percentages, choose compatible food-grade or industrial-grade ingredients, and specify any additives or microencapsulated indicators required for a sharp green shift in the presence of methane while remaining inert to air. • Provide a concise, repeatable lab-scale procedure (mixing order, temperatures, agitation time, pH targets) that can be scaled to pilot batches. • Outline safety data (MSDS components, flash point, shelf-life, storage) and compliance notes for typical U.S./EU regulations. • Supply a simple field-testing protocol: concentration of gas vs. response time, bubble integrity metrics, and visual colour chart.

Acceptance criteria

1. Colour shift to Pantone-like green within ≤3 seconds at 1 % v/v methane.
2. Bubbles remain intact ≥10 seconds in still air at 20 °C.
3. No detectable staining on painted drywall or stainless steel after 30 minutes.

If proprietary dyes, fluorescence enhancers, or catalyst microbeads are necessary, detail costs and sourcing. Deliver the final formula, step-by-step method, and a brief technical report (.pdf or.docx). Budget: USD 250–750 Skills: Chemical Engineering, Product Development