Why we review routine factory records, not only capability lists
A supplier can list dozens of tests on a website, but a buyer needs to know whether those checks appear in ordinary production records. During this visit, we selected one incoming-film report and one finished-pouch report from the factory's routine files. They were not created as a GreenPack Life marketing sample, and we have anonymized supplier and employee information before publishing any evidence.
This approach helps us evaluate the working quality system: what the factory checks before conversion, what it checks after pouch making, how results are recorded, and which questions remain open. We still verify the exact production site, method, conditions, lot, equipment status, and release decision for a customer's order rather than assuming that one historical record covers every product.
Incoming PE film checks start before the pouch is made
The incoming-film record covered a low-temperature PE sealant film. It recorded a nominal web specification around 585 mm by 67 µm, a measured width of 587 mm, and a measured thickness of 72 µm. It also included MD and TD tensile strength, elongation, outside coefficient of friction, treated-surface tension, a 120 °C heat-seal condition, and heat-seal strength of 11.706 N/15 mm against a listed minimum of 10 N/15 mm.
These checks support process consistency. Width and thickness affect material identity and pouch dimensions; tensile and elongation affect converting behavior; surface tension supports print or laminate adhesion; COF influences feeding and web handling; and heat-seal response helps define a usable sealing process. None of them, on their own, proves the oxygen or moisture barrier of the complete pouch.
The finished pouch record connects barrier, seals, and laminate bond
The finished record identified a three-side-seal pouch with a PET12/PE80 structure and 92 µm total thickness. It recorded side-seal strength of 30.8 N/15 mm and bottom-seal strength of 24.7 N/15 mm against listed minimums of 12 N/15 mm. PET/PE bond strength was 2.3 N/15 mm against a listed minimum of 0.6 N/15 mm, and residual solvent was 2.15 mg/m² against a listed maximum of 5 mg/m².
These values are useful because they move the discussion beyond appearance. Seal strength addresses formed-pouch seams, bond strength helps screen for delamination risk, and residual-solvent control relates to printing, lamination, curing, and release. A buyer should still specify the exact seal location, specimen direction, conditioning, failure mode, sampling frequency, and acceptance rule for the ordered pouch.
What the sampled OTR and WVTR results mean
The finished-pouch record listed an oxygen transmission rate of 39.268 cm³/(m²·24 h) against an internal limit of 100, and a water-vapor transmission rate of 1.059 g/(m²·24 h) against an internal limit of 10. Lower values indicate less gas or water vapor passing through the tested specimen under the stated test setup. The factory laboratory also contained dedicated gas- and water-vapor-permeability equipment, which supports the presence of relevant barrier-testing capability at the site.
These numbers should not be turned into a universal high-barrier or shelf-life promise. The reviewed record did not show all temperature, relative-humidity, pressure, conditioning, replicate, and specimen details needed for a fully normalized comparison. The equipment labels and the report references also make method confirmation important. For a customer order, we align the method and conditions first, then compare the proposed structure against the coffee, grind, pack atmosphere, climate, distribution time, and shelf-life target.
Residual-solvent testing adds a process-control checkpoint
The factory laboratory included a gas chromatograph labeled for residual-solvent testing, while the sampled finished-pouch record reported 2.15 mg/m² against a listed maximum of 5 mg/m². Residual-solvent review is relevant to printed and adhesively laminated flexible packaging because the result can reflect ink, adhesive, drying, curing, storage, and sampling controls.
For a commercial order, we do not treat one photographed instrument or one historical result as a permanent guarantee. We request the applicable method, target compounds or total result, sampling stage, release limit, lot identity, and evidence tied to the actual printed and laminated construction.
Tensile, peel, and seal data help connect material to pouch performance
The factory's electronic tensile equipment was labeled for tensile, heat-seal, and peel testing. The sampled records included MD and TD tensile or elongation results, PET/PE bond strength, and finished side- and bottom-seal strength. Together, these tests can help detect inconsistent film, weak lamination, or a seal process that is not centered within its intended operating window.
Our review does not stop at the word Qualified. Each recorded result should be checked against its stated limit, method, direction, and release rule, and any exception should be explained before it becomes evidence for a buyer's order. This is one reason first-hand record review is more useful than collecting an unsigned equipment list.
Coefficient of friction affects handling and packing-line stability
The incoming-film record included an outside COF result around 0.241 against a listed maximum of 0.25, while the finished-pouch record listed an inner-to-inner COF of 0.121 against a maximum of 0.6. The laboratory also contained a dedicated coefficient-of-friction tester. COF can influence how film unwinds, how pouches separate and open, and how material behaves in feeding, filling, sealing, and stacking.
A low or high number is not automatically better for every line. The target should match the customer's pouch machine, filling method, zipper and surface finish, and the factory should define which surfaces, conditioning, direction, and method are being compared.
What this onsite evidence proves - and what it does not
The records and equipment support a reasonable conclusion that the factory operates a real laboratory workflow covering incoming film, mechanical performance, sealing, lamination, residual solvent, and barrier testing. They also show that GreenPack Life can review the difference between a raw-film record and a finished-pouch record and translate both into buyer questions.
They do not prove that every pouch from the factory has the same OTR, WVTR, seal strength, bond strength, or residual-solvent result. They do not establish third-party laboratory accreditation, food-contact compliance, valve performance, gross-leak control, light and aroma barrier, transit performance, or a stated coffee shelf life. Those items require separate documents, agreed methods, representative production samples, and project-specific validation.
How GreenPack Life turns factory evidence into a buyer QC plan
Before quotation, we separate the coffee application, pouch geometry, material structure, barrier target, valve, zipper, print route, destination, and shelf-life expectation. During sampling, we ask the factory to identify which tests apply to the proposed construction and whether results come from flat film, formed pouches, or a filled package. Before production, those requirements become a signed specification with methods, conditions, units, tolerances, sampling, and release authority.
For mass production, the useful evidence is a traceable lot package: material identity, production code, dimensions and thickness, print and appearance checks, bond and seal data, barrier results where specified, residual-solvent evidence where relevant, valve and leak checks, retained samples, carton data, and any approved deviation. This is how an onsite factory visit becomes practical risk control for a coffee brand rather than a photo tour.