Mocom ALCOLOR SAN OR5048-16 is introduced into ABS consumer electronics enclosures as a SAN-carrier orange masterbatch at a let-down ratio of 2 wt% to 4 wt%, depending on the OEM colour coordinate and the effective wall thickness. In a high-gloss router housing with a nominal wall of 2.0 mm, the base ABS is pre-dried in a desiccant dryer at 80°C for 2 h to 4 h to achieve residual moisture below 0.1%; wet resin above 0.1% residual moisture is the dominant cause of splay, gate blush, and pigment agglomeration in this viscosity range. Barrel temperatures are set between 210°C and 250°C, and the mould temperature is held between 40°C and 80°C to balance flow length and surface gloss. A general-purpose screw with an L/D ratio of 20:1 or higher is normally sufficient because the SAN carrier is thermodynamically similar to the ABS matrix; a separate high-shear mixing section is not required when the masterbatch is dosed gravimetrically into the main feed throat. On a 1,200 kN electric machine running a four-cavity enclosure tool, screw recovery stability is more sensitive to barrel-zone temperature control than to the masterbatch addition itself; a drift of 15°C in the rear zone can shift melt viscosity enough to alter colour dispersion quality. The masterbatch package should be kept sealed before use; if exposed to ambient air at relative humidity above 60%, a dry-air dryer at 60°C to 70°C for 2 h is standard for SAN-carrier masterbatch. The moulding plant should verify colour acceptance by instrumental measurement using ISO 11664-4:2008 CIELAB coordinates and ASTM D2244-21 for ΔE*ab; visual inspection is insufficient for high-volume EMS programmes that require ΔE*ab below 1.0 across an eight-hour production run. Because enclosures are often specified to UL 94 V-0 at a wall thickness of 1.5 mm, the addition of the colour masterbatch must be validated within the certified ignition-resistant formulation; the masterbatch itself does not provide a flame rating. For laser-marked top covers, the pigment must also survive the local thermal cycle of the marking station without forming a carbonised halo; this is checked at the actual production laser power and frequency.

Scratch resistance and mar resistance of pigmented ABS covers are influenced more by mould surface polish and filler content than by the SAN carrier; the masterbatch should not be relied on to modify surface hardness. When the enclosure is subjected to abrasion in end use, the converter can evaluate surface damage using ISO 19252:2008 under a defined normal load. The colour masterbatch contains no solvent, and the SAN carrier has no intentional plasticiser; migration of the pigment into solvent-based screen-printing inks is therefore not expected, but pack compatibility with pad-print ink should be tested when the print is applied to a flame-retardant ABS compound. Published data for the exact OR5048-16 formulation in this specific enclosure configuration is limited; qualification batches should be run at the production shot weight and screw recovery time.

Why Does a Hot-Runner SAN Jar Wall Show Asymmetric Colour Drift?

In SAN storage jars, beverage stand components, and appliance windows, Mocom ALCOLOR SAN OR5048-16 is typically dosed at 1 wt% to 3 wt% to develop a warm orange tone without converting a naturally transparent SAN grade into a fully opaque material where transparency is still specified. When a multi-cavity hot-runner tool produces one cavity darker than the others, the cause is usually residence-time imbalance in the hot-runner manifold rather than incomplete dispersion of the masterbatch. The SAN carrier softens within the matrix melt stream; the hot-runner temperature should be kept between 220°C and 240°C for a SAN-base compound, and the nozzle temperature should not exceed the upper barrel limit by more than 10°C. A valve-gate system with an unbalanced manifold creates local hold-up where orange pigment can undergo thermal ageing; this appears as a shift in hue rather than a loss of opacity. Moulders should map cavity-to-cavity fill using short shots or cavity-pressure sensors before adjusting the masterbatch concentration. Total colour difference is measured as ΔE*ab under ASTM D2244-21; for transparent SAN articles, the assessment is usually done by transmission spectrophotometer.

Food-contact suitability of the finished SAN jar is not provided by the masterbatch supplier unless the specific finished-article formulation is evaluated. Under EU legislation, compliance with Regulation (EU) 10/2011 is the responsibility of the converter or brand owner; migration testing must use the appropriate food simulant and time/temperature conditions. For the North American market, any determination must be based on the relevant 21 CFR section for the base polymer and colourant in the finished article. The processor should not dilute the SAN masterbatch with a universal carrier containing polyethylene wax if a food-contact declaration is required; such a blend alters the additive package and may fail finished-article migration testing.

In thin-wall cosmetic closure and compact housings, the masterbatch is often dosed at 2 wt% into a high-flow ABS or SAN moulding compound with a melt volume-flow rate of 20 cm³/10 min to 40 cm³/10 min measured by ISO 1133-1:2022 at 220°C/10 kg. The gate is normally a hot tip or tunnel gate with a diameter of 0.8 mm to 1.2 mm; the masterbatch must not contain hard agglomerates that could plug the gate or produce visible streaks in a part with a nominal wall below 1.2 mm. The SAN carrier is compatible with these matrices, so the main process risk is not delamination but colour drift when the cooling time is below 8 s and the melt temperature is pushed to the upper end of the range. Mould temperature control at 30°C to 60°C is typical for thin-wall ABS cosmetic parts; the lower mould temperature reduces cycle time but increases orientation, which can alter perceived colour depth at sharp corners. Dimensional stability of the closure is verified with DIN 16742:2013 unless the drawing specifies a different tolerance standard.

Environmental stress cracking is a more serious failure mode than colour fade for cosmetic packaging. ABS and SAN are susceptible to cracking under contact with ester-based creams, ethanol-based toners, and surfactant-containing lotions. The correct evaluation method is ISO 22088-3:2006 or an internal strain-jig test using the actual filling formulation; a visual inspection after simple immersion is not sufficient because crack initiation time is strain-dependent. The pigment system in the orange masterbatch is expected to remain bound in the SAN carrier, but any migration into a contacting liquid should be assessed by the customer’s extraction protocol, because no single ISO standard covers all cosmetic contact scenarios. Acetone and acetate-based nail enamels are known stress-crack agents for SAN and ABS; the orange masterbatch cannot alter the base resin’s chemical resistance. Such pack designs require EVOH barrier liners or an alternative polymer, not a colour masterbatch reformulation.

When the SAN Carrier Meets PC-Rich ABS Alloys: Compatibility Cut-Off

Mocom ALCOLOR SAN OR5048-16 is compatible with the styrene-acrylonitrile phase of ABS and ABS/PC blends, but in polycarbonate-rich systems the SAN carrier is not an inert spectator. At PC content above 60 wt%, the SAN carrier can localise at the PC/SAN interface during melt blending, creating a small but measurable depression in low-temperature impact toughness. The effect is not linear with addition level; it is most often observed when the masterbatch is dosed at 4 wt% or higher into a PC-rich blend intended for thin-wall electrical enclosures or automotive interior structural parts. Processors should compare the natural compound and the masterbatched compound using ISO 179-1:2010 Charpy notched impact at -30°C and 23°C, and ISO 75-2:2013 Method A at 1.8 MPa for heat deflection temperature. A change in notched impact greater than 10% at low temperature is usually considered significant for safety-relevant brackets.

When the PC content is below 40 wt%, the SAN carrier is generally acceptable, but the processor should still confirm melt flow-rate stability because pigment surface treatments can slightly shift melt viscosity or thermal stability depending on the additive package. The relevant method is ISO 1133-1:2022 at the same temperature and load used for the natural ABS/PC grade; typical conditions are 260°C/5 kg or 260°C/10 kg depending on the base resin. The let-down ratio should be treated as a variable in the approved recipe, especially if the part is sold as a UL 94-certified moulding. Any change outside the certified masterbatch range may invalidate the certification and requires re-notification to the certification body. Published data for the exact OR5048-16 formulation in PC-rich blends is limited; therefore the cut-off must be established on the production formulation rather than inferred from general masterbatch behaviour.

The upper melt-temperature limit for the masterbatch itself is not published; the carrier class begins to degrade when held above 280°C for prolonged residence times, but the exact onset time depends on the base resin and screw geometry. Do not combine Mocom ALCOLOR SAN OR5048-16 with polyamide or polyolefin carriers in a single dry blend; the immiscible carrier phases will produce surface specks and inconsistent colour development, and the resulting compound may exhibit localised delamination at knit lines.

ASA/ABS Outdoor Dwell and Xenon Arc Lightfastness Thresholds

ASA/ABS exterior trim, sensor housings, and outdoor drainage components are a realistic downstream segment for Mocom ALCOLOR SAN OR5048-16 because the SAN carrier is miscible with the acrylate-styrene-acrylonitrile phase of ASA and does not introduce an incompatible carrier residue. The let-down ratio for full hiding in a 2.5 mm wall is typically between 2 wt% and 5 wt%; lower additions are used for colour tinting of translucent grades, but outdoor colour stability of a tinted translucent article is more difficult to control. Accelerated weathering should be conducted on the actual moulded part or plaque using ISO 4892-2:2013, daylight filters, and a black-standard temperature of 65°C; the test is continued until a specified ΔE*ab limit is reached. Exterior non-painted trim often specifies ΔE*ab below 3.0 after 1,000 h, while body-colour visible parts may require ΔE*ab below 2.0 after 2,000 h. The exact UV resistance of the orange pigment in OR5048-16 should be verified with the supplier’s spectral reflectance data and not assumed from the masterbatch name.

The SAN carrier does not confer UV stability to the ASA/ABS matrix. If the base resin lacks an adequate UV stabiliser package, the polymer will yellow and chalk around the pigment, producing a visible surface haze that is not attributable to colour fade. Gloss retention is measured under ISO 2813:2014 at 60°; a drop of more than 30% after outdoor exposure is often interpreted as matrix surface degradation. For drainage or rainwater goods, impact retention at -20°C is evaluated by ISO 179-1:2010; the addition of a SAN-carrier masterbatch should not be assumed to be inert in impact-modified ASA grades. Batch-to-batch variation is controlled by the masterbatch supplier’s internal colourimetric specification, but the converter’s incoming inspection should include a pressed plaque and spectral measurement under controlled conditions.

Thermoforming-Grade Sheet Requires a Screw Recovery Constraint

Sheet extrusion of SAN or ABS coloured with Mocom ALCOLOR SAN OR5048-16 at 2 wt% to 4 wt% is run on single-screw extruders with a grooved feed section and a static melt mixer between the barrel and the die. In this process, the SAN carrier is thermorheologically close to the matrix, so the limiting process variable is not dispersion but screw recovery and melt-pressure stability at the screen pack. Sheet thickness is specified at 0.5 mm to 1.5 mm for thermoforming-grade stock; thickness variation is measured under ISO 4593:1993 and is influenced mainly by die bolt adjustment, melt temperature uniformity, and roll stand tension rather than by masterbatch dosing. The extruder barrel profile is typically set between 210°C and 240°C for SAN and 210°C to 250°C for ABS; the die temperature is held within 5°C of the front-zone set point to avoid transverse colour variation.

Lip plate deposit is a practical maintenance issue in long sheet campaigns. Although the SAN carrier is thermally stable under normal processing, low-molecular-weight fractions and pigment surface treatments can accumulate on chrome-plated die lips after 12 h to 24 h of continuous running. The deposit is usually removed by mild abrasive cleaning during shutdown; continuous monitoring of melt pressure before the screen pack provides an early indication of screen blinding. Regrind must be dried to below 0.1% moisture and blended at a controlled ratio; wet regrind entering the extruder creates a two-phase melt that produces surface pitting in thermoformed parts. Published data for the exact OR5048-16 formulation in cast sheet is limited; the processor should establish a run-in trial to confirm the specific masterbatch lot does not produce visible specks in a 1.0 mm sheet at the intended let-down ratio.