Rifra has always developed anti-UV formulations by matching customer requirements with what base chemistry makes possible.
Those who choose us gain the support of a team of technicians who build the best formulation around the specific raw material mix of the finished part, and who help select the right loading according to wall thickness and expected service life.
| Every corporate function looks at UV stabilization from a different angle: production managers want confirmation on product and process quality control, R&D wants to develop increasingly high-performing products, marketing looks for new market opportunities, and technical service has to guarantee regulatory compliance to its own customers. Rifra recognizes each of these needs, because it manages the very same ones on its own products, and draws on that experience to support customers on each front specifically. |
| 01 · Technology |
Quantifying the UV stabilizer in the finished part
How much UV stabilizer is actually present in a finished part, and in what form, is not something routine controls return. The loading in the formulation and the residual concentration in the product can differ because of processing, migration or degradation, and it is precisely this gap that makes it hard to establish whether a UV performance issue comes from the formulation itself or from how it was transferred to the part.
| Case study |
| On a UV-stabilized PP part, the customer reported performance below expectations despite a formulation nominally matching the validated one. FTIR analysis identified the classes of stabilizer present in the part, while HPLC quantified the residual concentration against the theoretical loading. Comparing the two revealed a significant gap, attributable to a combination of in-process degradation and surface migration. On that basis it was possible to set up a targeted correction, rather than adjusting the loading blindly. |
| How to proceed
Write to us with the type of part, the polymer and the UV stabilizer expected in the formulation, along with the kind of support you need: a one-off analysis on a single part or batch, guidance in defining an FTIR/HPLC method to run in your own quality control lab, or recurring spot analyses. We will reply with a tailored technical proposal. |
02 · Research and development
Recyclate contamination and stabilizer deactivation
UV stabilization on recycled polymers raises problems that rarely appear on virgin material: batch-to-batch variability, contaminants and prior degradation of the polymer make the response to additives less predictable, with direct effects on dispersion, color consistency and process stability
| Case study |
| On a post-consumer rPP, a stabilizer loading validated on virgin resin failed to deliver the expected performance, with premature degradation and localized yellowing. The cause was not underdosing of the additive, but the contaminants and oxidative residues typical of recycling: transition metals carried over from previous processing and free radicals generated by prior oxidation, which intercept or partially deactivate the UV stabilizer before it can perform its protective function. The route to a solution started from characterizing the incoming resin, and on that basis the anti-UV formulation was recalibrated by balancing the primary stabilizer with systems able to limit the interference of contaminants. |
| How to proceed
Let us know the polymer, the type of recyclate (post-industrial or post-consumer) and the anomalies you are seeing in terms of UV performance, yellowing or embrittlement. We will help you set up an initial characterization of the resin, useful to understand whether the issue lies with contaminants or with the anti-UV formulation itself, avoiding unnecessary overdosing. |
03 · Co-design
Anti-UV formulations for compostable polymers
Balancing UV resistance and biodegradability on a compostable polymer is not a direct extension of what is done on conventional materials: the stabilizer classes that perform best in photoprotection can interfere with the degradation mechanisms the material requires, and a dedicated experimental program is needed to find the right balance for the application and for the reference compostability standard.
| Case study |
| To develop a new line of compostable parts with UV resistance requirements, the work started from several parallel experiments, using different base chemistries, on the resins or resin blends indicated by the customer. The most promising formulations were processed on our pilot plants, reproducing the final part and wall thickness planned for production, and then verified through Xeno test and Bandol test. Comparing the results made it possible to select the formulation with the best balance between photoprotective performance, compliance with the intended biodegradation route and formulation cost. |
How to proceed
Tell us the polymer or resin blend, the reference biodegradability standard (home, industrial or soil) and the level of UV resistance expected in service. We will reply with a proposed experimental plan.
| 04 · Technical service |
Anti-UV for food packaging: compliance and raw material selection
In food packaging, the UV stabilizer does not only protect the packaging itself: UV absorbers, for instance, limit the light-induced degradation of the contents (fat oxidation, vitamin loss, changes in color and aroma) during exposure to artificial and natural light, typically prolonged on the retail shelf. Here, raw material selection cannot be separated from verifying compliance with mandatory food contact regulations, which vary by destination market and which sit alongside, without replacing, the voluntary industry standards.
| Case study |
| For packaging intended for a light-sensitive product, the customer needed effective UV protection across the spectrum relevant to the degradation of the contents, built with raw materials suitable for food contact in the destination market. The work started with a discussion between the technical departments of both companies to identify the best-performing formulation, while in parallel the regulatory departments jointly verified the applicable framework: the reference regulation for the market, any positive lists of usable substances, conditions of use and migration limits. Only after cross-validation by both regulatory departments was the formulation considered suitable for production start-up. |
How to proceed
Write to us with the type of food to be protected, the destination market of the packaging and any regulations you have already identified as applicable. We will reply with an initial joint technical and regulatory assessment.
| Every application has its own constraints |
| Our technicians will propose a tailored formulation. |
| Explore the range |
