XRF Thin-Film Sample Supports — XRF Support Films

Primary uses

• Forms the window between the sample and the analyser detector
• Supports the sample in the cup while transmitting the measured energy range
• Provides a consistent, low-interference support for repeatable measurement

Applications

• XRF elemental analysis of liquids, powders and granules
• Light-element determination where film choice affects the measured range
• Routine fuel, oil and process-liquid elemental screening
• Mining, cement and polymer elemental testing

Advantages

• Several polymers and thicknesses are available, so the window can be matched to the energy range being measured
• Supplied in sheets and rolls to suit both occasional and high-throughput cup preparation
• A low-cost consumable that has a disproportionately large effect on light-element performance

Limitations to consider

• Changing film type or thickness shifts light-element results, so a film change is a calibration event and should be documented as one
• Films can stretch, sag or fail under vacuum or with aggressive solvent samples
• Transmission behaviour, thickness and purity are manufacturer declarations for the specific film, verified against its documentation
• Every numeric property — assay, purity, residual content, pore size, retention behaviour, ash content, extractables, thickness, capacity and dimensional tolerance — is a property of one manufactured item from one production line. Values are read from the manufacturer's own technical documentation for the exact item offered and confirmed at quotation, never quoted from a category page.
• A manufacturer declaration and a verified result are not the same thing. Declarations state what the manufacturer controls to; suitability inside your own method, matrix and instrument is established by your own verification. Where a result must stand up inside an accredited scope, plan that verification before the item enters routine use.

How to choose the right grade

• Match the film to the elements being measured, since light-element work is where film choice shows most
• Keep film type and thickness constant within a calibration, and treat any change as a controlled change
• Confirm that the film suits the sample chemistry and the vacuum or helium configuration in use
• Once a consumable is inside a validated method, changing it has a cost: the change has to be justified, trialled and documented. Continuity of the identical item usually matters more than unit price, so state the incumbent item and the property that must be matched when a second source is being qualified.
• Buyers frequently search using the catalogue name of a manufacturer they already use. Those are third-party trademarks belonging to their owners and are never used as an Allzone product identity. Where an equivalent is being considered, equivalence is assessed against the two sets of documentation and confirmed by the laboratory's own verification.
• Exact specification is confirmed against supplier documentation at quotation.

Typical grades

• Variant selection is made on the instrument, apparatus and test method rather than on a grade ladder
• Where a manufacturer operates distinct quality or cleanliness lines for the same item, the line is identified per offer
• Any declared property is read from the manufacturer documentation for the exact item offered, never assumed from a family name
• Regulatory listing, certification, food-contact status and any scheme approval belong to a specific item, facility and jurisdiction, and they change scope over time. State what your programme or customer requires at the enquiry stage so it is checked against current documentation for the offered item rather than assumed from a product name.
• These items are offered for industrial, food, feed, water, environmental and materials-testing work. Nothing here is offered, positioned or documented for medical, clinical, diagnostic or human-specimen use, and no such suitability is implied.