Cosmetic Sachet Product Residue: Compare What Users Can Empty

For a single-use cream sachet, the buyer may want enough product to reach the user’s hand after one practical opening and squeezing sequence. That is a different endpoint from extracting the maximum possible amount by repeated rolling or scraping. Define the intended use before comparing package shapes.

A 2025 study by Klein, Tacker and Apprich examined emptying of cosmetic packaging and reported that residue depends on the product and package system. Its research results do not establish the performance of a PM sachet or a universal acceptance percentage. Use the study as a reason to evaluate the actual combination, not as a substitute for project samples.

Use the intended formula and fill quantity, or clearly label a substitute and what it cannot represent. Record storage history, use temperature, sample age, sachet dimensions and the opening presented to the user. Agree the action sequence and endpoint before collecting results.

Compare individual packages and retain the observations rather than reporting only the best sample. If intensive recovery is also useful, use a separately identified stage or sample group. Do not silently add an extra tool or repeated rolling to one design while calling both outcomes normal use.

An illustrative measurement plan can compare the full package, the package with residue after use, and the cleaned, dry packaging pieces. Keep the same set of pieces across the relevant measurements. If the torn top disappears from the final weighing, its missing plastic can be mistaken for removed product.

The laboratory or quality team should select a cleaning and drying approach that does not change the packaging mass materially and should address any product loss unrelated to the emptying action. This worksheet is not a standardized test method. Instrument capability, evaporation, sample handling and the size of the expected difference affect whether the result is meaningful.

Hypothetical values: the full sachet weighs 12.0 g. All cleaned, dry packaging pieces together weigh 2.0 g. After the agreed action, those same pieces plus retained product weigh 2.6 g. Initial contents are 10.0 g; retained contents are 0.6 g, or 6% of the initial mass. These are example numbers, not PM results or a pass threshold.

The calculation implies that 9.4 g left the package only if the measurement assumptions hold. It does not prove that all 9.4 g reached the user’s hand: some could be on a tool or another surface. If delivery matters, collect and measure it separately. Do not label residue reduction as a shelf-life, safety or sustainability result.

If residue clusters near an edge or fold, document the location alongside the use sequence. Ask for a clearly identified alternative and repeat the same comparison before concluding that its geometry is better. If the problem occurs during opening, address it in the sachet opening review rather than mixing opening failures into an emptying result.

For custom cosmetic sachets, send P&M the formula category, fill quantity, dimensions, intended use, opening concept and sample conditions. P&M provides U.S.-based support with owned-factory packaging production in Guangdong, China. Formula compatibility and finished-package validation remain project-specific; a low residue observation alone does not approve the material.