In sachet filling, defining a product merely as a cream, gel or liquid is not enough. The packaging film must be assessed together with the formulation supplied by the customer, the target fill quantity, the way the sachet will be used and the expected storage conditions. A line may be able to fill the product, yet the finished pack can still fall short on seal integrity, ease of opening, print layout or appearance if these variables are not aligned.
This guide explains what brands should clarify before requesting a quotation for sachet filling. RENASAN’s relevant service covers contract filling and packaging of customer-supplied creams, gels and liquids in sachet format. It should not be read as a formulation-development or R&D service.
Why is packaging film part of the filling quotation?
Fill quantity, sachet width and sachet length are connected, but dimensions alone do not define the pack. Film structure, thickness, heat-seal behaviour, print surface and opening features such as a tear notch can all affect the outcome. A request described only as “5 ml cream sachet” may therefore be insufficient for reliable costing and sampling.
The quotation brief should bring together the product’s physical characteristics, target fill quantity, single-use scenario, pack dimensions, film expectations and artwork requirements. This also makes supplier quotations easier to compare because the buyer can see whether every offer covers the same technical scope.
How should product-to-film compatibility be reviewed?
Viscosity and flow behaviour
Creams, gels and liquids do not behave identically during dosing. Flow behaviour can influence dosing consistency and how the product settles inside the sachet. Instead of using only a broad viscosity description, the buyer should provide a current physical sample, target fill weight and any available information about the product’s filling conditions. As the customer owns and supplies the formulation, the sample should represent the product intended for production.
Film structure and barrier expectations
A packaging film may be a single layer or a laminate. The layers can serve different purposes, including printability, mechanical strength, sealing and product contact. A simple rule such as “thicker is better” is not a sound specification. The relevant question is whether the selected structure is suitable for the product and its intended use.
If the product has particular sensitivity to light, moisture, oxygen or odour transfer, that requirement should be stated at the start. A standard film structure should not be assumed to provide a specific barrier unless the requirement and material suitability have been verified.
Seal area and leak resistance
The seal keeps the product within the sachet, but seal integrity does not depend on temperature alone. Film structure, the possibility of product contamination in the seal area, fill quantity and machine settings interact. During sample review, buyers should inspect the consistency of the seal lines, edge condition and any sign of leakage under reasonable handling pressure.
Why should ease of opening be specified separately?
A sachet that users cannot open does not perform its intended function. A pack that tears too readily may create different problems during transport or storage. Notch position, tear direction, seal width and mechanical film properties should therefore be considered together.
A tester may be expected to open easily by hand. A sachet intended for professional use may follow a different use scenario. “Easy-open” is not a measurable instruction by itself; sampling should define who opens the pack, in what setting and by which motion.
How should artwork be prepared for technical approval?
Artwork approval and production approval are not the same step. The file should be checked for bleed, cutting area, seal zones, mandatory text and any reserved space for batch information. The visible face of a sachet is not necessarily identical to the safe printable area.
The brand owner remains responsible for keeping the brand name, product name, declared quantity and legally required information current. A contract filler works from the approved artwork and product information it receives. Recording the final file version before printing reduces the risk of repeating an outdated claim or typographical error across a production run.
What should be checked when approving a sample?
- Review sachet width, length and target fill quantity together.
- Inspect the seal lines and check that product has not entered the seal area.
- Confirm that notch position and tear direction match the intended use.
- Check that printed information remains readable and clear of cut and seal zones.
- Look for wrinkles, pinholes or visible deformation on the pack surface.
- Record the date and version of the approved sample.
A sample cannot represent every variable in a full production run, but it makes the buyer’s expectations visible and testable. When the project moves from quotation to order, everyone should be able to answer one simple question: which version was approved?
Minimum information to include in a quotation request
A useful quotation request states the product type, target fill quantity, estimated order volume, required sachet dimensions, film and print expectations, secondary packaging and delivery plan. If a product sample is available, the buyer should also confirm whether it represents the current formulation.
Our guide on clarifying the product and intended use before sachet filling explains how to prepare the product brief. When comparing commercial offers, review unit price and total cost together.
How to start a sachet filling enquiry with RENASAN
If you have a finished cream, gel or liquid product and need sachet filling and packaging, share the product sample, target fill quantity, estimated volume and packaging expectations. The RENASAN team can then identify the technical information needed to assess the request against available production capabilities.
Frequently asked questions
How is packaging film selected for sachet filling?
Consider the formulation, fill volume, intended shelf life and use conditions, then evaluate suitable film structures with samples and relevant tests.
Why should seal integrity be checked on samples?
Film construction and sealing conditions interact. Suitability should be assessed using the actual product and intended pack format.
How is easy opening evaluated?
Review the notch, film structure and seal area together, and test opening performance with representative samples.
What information is needed for a quotation?
Share the product specification, fill volume, sachet dimensions, estimated quantity, artwork and expected delivery requirements.
Contact RENASAN with a clear product and packaging brief so the discussion starts from comparable, practical information.