Direct answer
Approve coffee bag valve placement twice: first on a dieline that marks seals, folds, zipper and critical graphics, then on an assembled bag filled with the intended coffee. The flat proof identifies planned coordinates; the filled sample reveals whether the valve is obscured, pressed, creased or difficult to inspect. Valve function and package leakage still require separate project-specific checks.
Why a flat artwork proof is only the first view
A valve punch occupies real panel space. Coffee fills the bag, changes its profile and may put a graphic, fold or neighboring bag against the installed valve. Place the actual valve model and intended panel on the approved dieline before final print approval. Mark the zipper, top seal, side or bottom folds, date code and any image or legally required copy that must remain readable.
P&M supports qualified one-way valves in custom coffee bags. Its governed inspection scope checks clearance from zippers, seals, folds and critical artwork, then checks the installed bag for missing, reversed, displaced or damaged valves. A coffee-bag artwork guide similarly calls for valve and seal positions before final artwork; its supplier dimensions and production method are not P&M claims.
Use three proofs for three different decisions
The print proof is about position and legibility, the assembled empty bag about converting and valve attachment, and the filled bag about real geometry and handling. None substitutes for the next. Include front, back and side views if a case or shelf presentation can hide the installed valve. Avoid placing critical copy where bag expansion, a fold or the valve disc will interrupt it.
This is distinct from the valve inspection evidence guide, which asks what records prove attachment and function. Here the owner is the combined artwork and filled-bag layout approval.
| Approval artifact | Decision it supports | What it cannot prove |
|---|---|---|
| Marked dieline | Planned valve clearance and graphic hierarchy | Installed valve seating |
| Assembled empty bag | Punch location, weld appearance and panel alignment | Filled shape or coffee contact |
| Representative filled bag | Visibility, deformation, shelf and case orientation | Aroma shelf life or valve function without tests |
Recheck after a size or valve change
A new fill weight, zipper, valve model or bag width changes the available panel area. Run the placement review again rather than carrying forward an old proof. On larger packs, inspect the intended case orientation and compression path; the large-coffee-bag case trial guide covers that separate load question.
For valve function, specify the chosen component's test method and acceptance criteria. P&M's governed process distinguishes leakage at the valve body, installation hole and weld from leakage at the bag seals. Visual presence alone cannot prove a one-way function or finished-bag shelf life.
Send an artwork-ready coffee bag brief
Provide coffee form, fill weight and bag reference, roast-to-pack timing if known, chosen or proposed valve, zipper, artwork panels, date-code position, case orientation and quantities by SKU. Request the exact valve placement overlay, an assembled sample and a filled-layout sign-off before releasing production artwork.
General educational information only. Materials, performance, compliance, claims, quantities, and timing require confirmation for the exact packaging project.