# How does AromaFlow™ release scent without staining, and how does ThermoBreathe™ safely control heat pack temperatures?

> Source: https://breathablefilm.com/news/knowledge-center/how-does-aromaflow-release-scent-without-staining-and-how-does-thermobreathe-safely-control-heat-pack-temperatures/
> Author: kh_sales02
> Published: 2026-05-07
> Updated: 2026-08-28

## Key takeaways

- AromaFlow™ and ThermoBreathe™ are both specialized laminates in Kae Hwa's FunPack™ functional packaging series, each engineered as a molecular gatekeeper for a different gas or vapor.
- AromaFlow™ uses an oleophobic, microporous membrane sized so aromatic gas molecules pass freely while larger liquid essential-oil droplets are physically blocked, preventing the oil stains common with paper sachets.
- ThermoBreathe™ acts as a metering valve that restricts the oxygen feeding a heat pack's iron-powder exothermic reaction to a steady level, keeping the pack at a safe constant temperature for 12–24 hours instead of spiking and overheating.

## Frequently asked questions

### How does AromaFlow release scent without staining, and how does ThermoBreathe safely control heat pack temperatures?

AromaFlow uses an oleophobic, microporous membrane sized so volatile aromatic gas molecules can diffuse freely into the air while the pores physically block larger liquid essential-oil droplets, preventing the oil stains common with traditional paper sachets. ThermoBreathe controls heat packs by acting as a microscopic metering valve with a precisely tuned air permeability rate: it restricts the oxygen feeding the iron powder's exothermic reaction to a steady controlled level, keeping the pack at a safe constant temperature while extending its heating duration to 12-24 hours instead of letting it spike and overheat.

### Why can't a regular paper sachet or heat pack achieve the same safety and performance?

A paper sachet has no way to separate liquid oil from its vapor, so oil soaks through and stains fabric. A heat pack without a controlled-permeability membrane lets oxygen flood the iron-powder reaction, causing it to spike hot and burn out quickly instead of releasing heat steadily over many hours.