In the research and development and production chain of aerosol products, the propellant plays a crucial role, which is like the “heart” of the aerosol, providing jet power for the product, and at the same time profoundly affecting the product's safety, environmental performance and the final use of the effect. For aerosol filling machine manufacturers, a comprehensive and in-depth grasp of the unique properties of the various types of ejectants, is to achieve efficient operation of the production process, to ensure product quality is stable and reliable, and to provide customers with customized solutions for the key. In the following, we will analyze in detail the types of mainstream ejectants on the market, their respective characteristics and their main application scenarios.
1. Hydrofluorocarbons:
Representative: HFC-134a (tetrafluoroethane), HFA-227ea (heptafluoropropane)
Advantages: ODP=0; chemically inert, good compatibility; non-flammable; excellent performance (moderate vapor pressure, good solubility, especially for pharmaceutical inhalants); odorless.
Disadvantages: Very high GWP (HFA-134a GWP=1430); high cost; subject to strict regulations and phase-out (especially in non-pharmaceutical applications).
Main applications: Gold standard for pharmaceutical inhalants (asthma, COPD medications); some precision electronic cleaners requiring high safety, high-end cosmetics (gradually being replaced).
2. Hydrofluoroolefin:
Representative: HFO-1234ze(E) (trans-1,3,3,3-tetrafluoropropene-1-propene)
Advantages: ODP=0; very low GWP (≈1); non-flammable; chemically similar to HFCs, good solubility and performance; considered the most promising environmentally friendly alternative to HFCs.
Disadvantages: Currently high cost; relatively short history of large-scale applications; supply chain still under development.
Main applications: Rapidly growing field, replacing HFCs in personal care products (hairspray, antiperspirant), household cleaners, industrial sprays, pharmaceutical inhalants (some new drugs under development).
3. Liquefied petroleum gas(LPG)
Represented by: Propane (A-108), Isobutane (A-31), n-Butane (A-17), often mixed in proportions (e.g. A-46, A-70).
Advantages: ODP=0; very low GWP (≈3); low cost; abundant sources; good solubility (especially for oily substances); wide range of vapor pressures (adjustable by mixing ratio); good performance.
Disadvantages: Highly flammable and explosive; odorous (needs to be scented to mask); requires special safety measures (production, filling, storage, transportation, use); tanks need to meet stricter safety standards (e.g., thickening, explosion-proofing); may be limited in areas where regulations restrict VOC content.
Main Applications: The most widely used dispensing agent worldwide, especially in Europe and Asia. Used in large quantities in personal care products (hairspray, mousse, antiperspirants, shaving foam), household products (air fresheners, furniture polish, fabric conditioners, insecticides), and industrial products (mold release agents, lubricants).
4. Dimethyl ether
Representative: DME
Advantages: ODP=0; very low GWP (≈1); excellent solubility (highly miscible with water, alcohols, and many organic solvents), well suited for aqueous formulations; moderate vapor pressure; relatively low cost.
Disadvantages: Flammable and explosive (similar to LPG); slight etheric odor; swelling of some rubber and plastic seals; careful selection of packaging materials.
Major Applications: Products requiring water-based formulations or high solvent solubility, such as hairspray (especially in Asia), air fresheners, some detergents, fabric conditioners, mold release agents.
5. Compressed gases:
Representative: Nitrogen (N2), Carbon Dioxide (CO2), Nitrous Oxide (N2O)
Advantages: ODP = 0; GWP = 0 (N2) or very low (CO2 ≈ 1, N2O ≈ 298 but in small quantities); non-flammable (N2, CO2); odorless (N2, CO2); low cost; high safety.
Disadvantage: Poor solubility (essentially insoluble), only suitable for suspension or emulsion formulations; tank pressure drops significantly with decreasing contents, resulting in inconsistent spray characteristics (hard at the start, weak at the end); larger tanks or special valves (e.g., bag valves) may be needed to maintain pressure; CO2 may lower the pH of the formulation (carbonic acid is formed), N2O has slight anesthetic properties.
Applications: Products that do not require high spray uniformity or can accept pressure variations, such as whipped cream (N2O), some aqueous coatings, some detergents, some food sprays. Bag valve systems can ameliorate pressure problems, but at an increased cost.
As a professional manufacturer of aerosol filling machines, Wejing Intelligence recognizes that matching the characteristics of the dispersant to the filling process is critical to improving productivity and ensuring product quality. Whether you need filling equipment for hydrofluorocarbons (HFCs), hydrofluoroolefins (HFOs), liquefied petroleum gas (LPG), dimethyl ether (DME), or compressed gases, we can provide you with a one-stop solution. From equipment customization (including explosion-proof design, precise pressure control, etc.), to process optimization (adapting filling parameters to different formulations), to compliance support (keeping abreast of global environmental regulations), we help you efficiently produce aerosol products that meet market needs.
Contact us today for a technical solution that's just right for you!
