PIGMENT RED 48:2/ HP RED 23124
Pigments for Plastics & Masterbatch
Technical Information
Technical Information
What Is Pigment Red 48:2
Pigment Red 48:2 (CAS 7023-61-2, CI 15865:2) is a Monoazo Lake pigment based on BONA (β-oxynaphthoic acid) precipitated as a calcium salt. This bluish-red (ruby) shade pigment features two acidic functional groups—sulfonic acid and carboxylic acid—which form the lake structure. Compared to PR 48:1 it is distinctly bluer, while remaining noticeably yellower than PR 57:1. Its chemical form grants good migration resistance in plasticized PVC and stability against blooming in plastics, making it a versatile workhorse across multiple polymer systems.
Why Choose HP RED 23124
HP RED 23124 is specifically engineered for plastics processing—injection moulding, extrusion, film blowing—in polypropylene (PP), polyethylene (PE), and PVC. While standard PR 48:2 grades perform adequately in inks, many plastics-grade variants suffer from migration or warpage in thin films. This grade addresses those shortcomings: it delivers high tinctorial strength that rivals PR 53:1 in hiding power per unit cost, yet with significantly better migration resistance. When compared to PR 48:1 or PR 48:4 in PE film, HP RED 23124 remains bloom-free even at elevated processing temperatures. Its calcium-lake structure also minimizes plate-out during injection moulding, reducing downtime. For converters seeking a bluish-red plastic masterbatch that holds its shade without bleeding into light-coloured adjacent parts, this grade offers a reliable, cost-competitive alternative to higher-priced specialty reds.
Key Features
- The calcium BONA lake structure ensures outstanding migration resistance, preventing colour bleeding into adjacent light-coloured plastic parts or onto substrates during prolonged storage.
- High tinctorial strength reduces pigment loading per kilogram of masterbatch, delivering cost savings while maintaining colour depth in thin films and moulded parts.
- Stable bloom performance across polyolefin and PVC processing temperatures eliminates the risk of surface haze or recrystallisation, even in highly plasticised formulations.
- Bluish-red (ruby) colour space fills the gap between yellower PR 48:1 and bluer PR 57:1, allowing formulators to achieve bright reds without crossing into magenta territory.
- Consistent dispersion in PE/PP carrier resins reduces speck formation during film blowing and injection moulding, improving finished-part appearance and yield.
Recommended Applications
Primary: Plastics masterbatch for injection moulding (PP, PE), extrusion (PVC profiles, tubes), and film blowing (LDPE, LLDPE, HDPE).
Secondary: Gravure packaging inks (where standards require a bluish process red); publication inks; surface printing on coated paper and board. For ink applications, tint strength adjustment may be needed versus standard PR 53:1 formulations.
Technical Data:
| Product Information | ||||
|---|---|---|---|---|
| Chemical Type | Azo | CAS NO. | 7023-61-2 | |
| C. I. Name | Pigment Red 48:2 | EINECS / ELINCS NO. | 230-303-5 | |
| C. I. Constitution No. | 15865:2 | Chemical Formula | C18H11ClN2O6SCa | |
| Technical Performance | ||||
|---|---|---|---|---|
| Full Shade | Tint | |||
| Full Shade | Tint | |||
| Weather Resistance | 4-5 | 3 | Heat Stability °C | 260°C |
| Light Fastness | 8 | 7 | ||
| Physical Properties | ||||
|---|---|---|---|---|
| Physical Form | Powder | Resistance to Acid | 4 | |
| Specific Density (g/cm3): | 1.65 ± 0.1 | Resistance to Alkali | 4 | |
| Specific Surface(㎡/g): | 58 | Migration resistance PVC | 4 | |
| Oil Absorption | 60 ± 10 | Low warping applications | Not suitable | |
| pH Value | 6.5 -8.5 | |||
| Volatile Matter | 1% max | |||
| Packaging | ||||
|---|---|---|---|---|
| 25kgs/bag 300kgs/Pallet | ||||
| Storage Shelf Life 5 years | ||||
| Should be stored in cool, dry and ventilate place. |
| TRANSPORTATION | ||||
|---|---|---|---|---|
| Avoid inversion, sunlight, moisture and crash. Avoid damage the package. |
- Light fastness: Light fastness rating is assessed on 1 to 8 Blue Wool scale where 1 = ‘Poor’ and 8 = ‘Excellent’.
- Heat Stability : Heat stability values given indicate the maximum temperature at which the pigment can be stoved for 10 min. on the full shade and in reductions without undergoing any significant change in shade.
- Oil absorption: The oil absorption is determined on the basis of EN ISO 787-5 and given in g linseed oil per 100 gm. pigment.
- Solvent bleeding: The bleeding in solvents is tested using the powder grades and the visual rating given on 1 to 5 Grey scale
where 1 = ‘Heavy bleeding’ and 5 = ‘No bleeding”
Disclaimer — This Technical Data Sheet reflects our best understanding of typical product properties at the time of publication. Listed values are representative of standard production and are not intended as specifications, contractual parameters, or fitness guarantees. Batch variations within normal manufacturing tolerances may occur; users should verify critical parameters against their own requirements before use. Processing methods, formulations, and end-use environments are beyond the manufacturer’s control. The buyer assumes full responsibility for confirming product suitability through its own testing and quality assurance. No intellectual property license is granted or implied. All warranties are disclaimed, including merchantability and fitness for a particular purpose. The manufacturer is not liable for incidental, consequential, or special damages. All sales are governed by the manufacturer’s standard terms, available upon request. This product may contain particles below 0.1 μm. Any user of this product is responsible for determining the suitability of Honor Pigments’s products for its particular application & to ensure that any proprietary rights & existing laws & legislation are observed.
Frequently Asked Questions About Pigment Red 48:2
1. How does HP RED 23124 differ from standard Pigment Red 48:2 grades in plastics?
HP RED 23124 is optimised for high-temperature plastics processing. Standard PR 48:2 (CAS 7023-61-2, CI 15865:2) from ink-focused producers often contains coarser particles or surface treatments unsuitable for thin-film extrusion. Our grade uses a controlled calcium-lake precipitation that yields finer, more uniform crystals. This improves dispersion in polyolefins and resists warpage in thick injection-moulded sections. In practical terms, you can process it at typical PP melt temperatures (220–260°C) without losing colour strength or developing surface bloom.
2. Can HP RED 23124 replace Pigment Red 53:1 in polypropylene?
Yes, but with a trade-off. PR 53:1 (Lithol Red) offers higher tinctorial strength and lower cost, but suffers from poor migration resistance—especially in plasticised PVC or multi-colour mouldings. HP RED 23124 delivers approximately 20–30% lower strength per weight, yet provides far better bleed resistance. For applications requiring contact with food simulants (e.g., PP bottle caps) or layered designs where red cannot migrate into white sections, HP RED 23124 is the safer choice. In opaque thin-film applications, you can compensate for its lower strength by increasing loading modestly and still achieve overall system cost parity.
3. Is this grade suitable for food-contact plastics?
HP RED 23124 (CI 15865:2, calcium salt of BONA lake) itself has no inherent food-contact approval—compliance depends on your local regulations (EU Plastics Regulation 10/2011, FDA 21 CFR 178.3297 for colourants) and migration testing in your specific polymer. The pigment’s calcium-lake structure typically shows low overall migration values in polyethylene and polypropylene. However, we strongly recommend end-use extraction testing because the sulfonic and carboxylic acid groups can interact with certain plasticiser systems (e.g., phthalates in flexible PVC) to form soluble complexes. For non-food PE film applications such as shopping bags or stretch wrap, it performs excellently.
4. Why does HP RED 23124 appear bluer than PR 48:1?
The difference lies in the metal cation and crystal lattice. PR 48:1 uses a manganese salt of BONA, which yields a more yellowish-red shade. HP RED 23124 (calcium salt, as defined by CI 15865:2) shifts the absorption maximum to a shorter wavelength, producing a distinct bluish undertone (ruby). Compared to PR 57:1 (Calcium 4B toner), HP RED 23124 remains yellower. If you need a neutral red for four-colour printing, note that this grade’s hue is closer to a process magenta than a warm red—ideal for packaging requiring true reds without orange cast.
5. How should I store HP RED 23124 to maintain dispersion quality?
Like all powder pigments, HP RED 23124 (CAS 7023-61-2) should be kept in a cool, dry environment below 30°C in sealed containers. Moisture absorption above 2% can cause agglomeration during masterbatch compounding, leading to specks or colour streaks in blown film. Because the calcium lake is chemically stable, humidity primarily affects flowability and dispersion—not the colour itself. For optimal performance in injection moulding, we recommend pre-drying the pigment at 70–80°C for 1–2 hours if the container has been opened in humid conditions. Do not exceed 100°C as extended heating may alter surface moisture equilibrium.