Over recent years, solid beauty bars have become a rising trend, either as shampoo, body wash, or hair conditioner. Syndet bars have been around for some time – the most well-known in the retail market is the Dove Beauty Bar, which can be used as a conventional soap bar for both body wash and shampoo.
Products like this are not wholly based on the generic term “soap” (i.e. an alkaline metal salt of a fatty acid, such as Sodium Cocoate) but instead on a blend of surfactants and fatty esters. The advantages of doing this include:
- Ingredients can be milder to the skin than neat soap
- Lower pH that can be adjusted closer to skin pH
- Can be produced by ‘hot melt’, so no milling machinery is needed (although ready-made noodles are available for milling like conventional soap – but this gives less scope for bespoke products)
- A larger range of additives will be compatible, allowing for more USPs
- Hair conditioner blocks can be produced with cationic additives not possible with soap
Base Ingredients in Solid Beauty Bars
Main Foaming, Cleansing and Conditioning Agents
(These are used in various combinations depending on the application)
- Sodium Cocoyl Isethionate (SCI): a mild, high-foaming surfactant, available in flake or powder form
- Sodium Coco Sulfate (SCS): a strong foamer, available in powder or needle form
- Sodium Cocoyl Methyl Taurate (SCMT): a mild, high-foaming powder
- Cocamidopropyl Betaine (CAPB): a foam booster and stabiliser, available in powder form
- Sodium Alpha Olefin Sulfonate (AOS): a high-foaming surfactant in powder form
- Stearyl Trimethylammonium Chloride: for conditioning blocks only (cationic)
- Behenyl Trimethylammonium Chloride (or Methosulfate): used in conditioner bars (cationic)
- Stearamidopropyl Dimethylamine: a non-cationic conditioning agent for conditioner bars
- Cationic Modified Guars: for skin and hair conditioning, suitable for combination bars
Structuring Agents
(These are used to produce the solid bar format)
- Glyceryl Stearate
- Cetearyl Alcohol
- Stearyl Alcohol
- Ethoxylated Esters
- Fruit and Vegetable Waxes (e.g. Mandorwax, Albiwax)
- Emulsifier/Structuring Systems (e.g. Linkwax AM200, Phytocream® 2000)
Formulation Considerations
- Melting Point: Critical for processing and for maintaining the stability of some additives.
- Solubility: Bars must last a reasonable number of uses. If too soluble, they dissolve too quickly; if not soluble enough, performance and foaming is compromised.
- Foaming: Rich, stable foam is essential. Foam boosters and stabilisers such as Cocoamidopropyl Betaine (Mackam® 2800) may be added, or a specific grade of Calcium Carbonate (Omyacare® S70 KP) which has proven foam enhancing properties.
- Colour: Some oils, fragrances, or actives may darken the bar. To get the product as white as possible, specific Calcium Carbonate grades can be used. Alternatively, you could colour the block using dyes and/or pigments.
- Cracking: Bars may crack with repeated use. A polymer such as Cosmosurf® CE140 prevents this, also acting as a film-former for a silky skin feel and dispersing agent for actives, ensuring they’re evenly distributed.
- Bio-Stability: While bars are water-free, once wet they may become contaminated. A preservative such as Linkguard PE is recommended for antifungal and antibacterial protection.
- Actives: Many actives can be added to enhance the effects on the skin and hair and possibly help to relieve skin problems. Deodorant actives can also be added, such as Zinc Ricinoleate (Flexicare™ ZR-P). At HARKE UK & Ireland, we have a wide range of skin actives available through our cosmetic principals. Some are featured in the example formulations below, and we have many more. Please contact our technical team for more information about these actives and their effects.
Example Formulation 1: Standard Shampoo and Body Wash Block
This is a standard-quality emollient block that leaves skin and hair feeling soft and conditioned:
| Sodium Cocoyl Isethionate | 46.0% |
| Sunflower Oil (Helianthus Annuus) | 9.5% |
| Mandorwax (Hydrogenated Vegetable Oil, Prunus Amygdalus Dulcis Oil, Tocopherol) |
5.0% |
| Mackam® 2800 (Cocoamidopropyl Betaine) | 10.0% |
| Linkwax AM200 (Cetearyl Alcohol, PEG-20 Mono Stearate) | 20.0% |
| Cosmosurf® CE-140 (Stearyl/Octyldodecyl Citrate Crosspolymer) | 5.0% |
| Linkguard PE (Phenoxyethanol, Piroctone Olamine) | 0.5% |
| Natural Ocean Breeze Fragrance N37575 | 4.0% |
Method of Manufacture
Blend SCI, Sunflower Oil, Mandorwax, Linkwax AM200, and Cosmosurf® CE-140 at 80°C. Homogenise thoroughly. Cool to 55-60°C. Add the remaining ingredients. Stir until homogeneous and pour into moulds.
Example Formulation 2: Premium Block with Actives
In this formulation, we have added special actives to enhance the beauty bar, giving better foaming and skin benefits and adding to the beauty bar’s unique selling points. This is just one example of how a standard block can be enhanced:
| Sodium Cocoyl Isethionate | 40.0% |
| Sunflower Oil (Helianthus Annuus) | 8.0% |
| Mackam® 2800 (Cocoamidopropyl Betaine) | 10.0% |
| Omyacare® S70 KP (Calcium Carbonate) | 2.0% |
| Mandorwax (Hydrogenated Vegetable Oil, Prunus Amygdalus Dulcis Oil, Tocopherol) |
4.5% |
| Phytocream® 2000 (Hydrolysed Wheat Protein, Glyceryl Stearate, Cetearyl Alcohol) | 20.0% |
| Cosmosurf® CE-140 (Stearyl/Octyldodecyl Citrate Crosspolymer) | 4.5% |
| BIO-Placenta (Speciality Peptide Blend, Bacillus/Folic Acid Ferment Extract, Sodium Hyaluronate, Caprylyl Glycol) | 0.5% |
| Dermalcare® LIA MB (Isoamyl Laurate) | 5.0% |
| Pea.Protein (Hydrolyzed Pea Protein) | 1.0% |
| Linkguard PE (Phenoxyethanol, Piroctone Olamine) | 0.5% |
| Sandalwood Fragrance N71325 | 4.0% |
Method of Manufacture
Blend SCI, Phytocream 2000, Dermalcare® LIA MB, Cosmosurf® CE-140, Mandorwax, and Sunflower Oil at 75°C. Add Mackam® 2800 and Omyacare® S70 KP. Maintain temperature and homogenise. Cool to 55–60°C. Add remaining ingredients. Stir until homogeneous and pour into moulds.
Next Steps
Whether you’re targeting hydration, cleansing, or unique sensorial effects, basic solid beauty bars can be easily enhanced with a wide range of functional and active ingredients that suit your brand’s needs.
All the ingredients featured here are part of HARKE UK & Ireland’s extensive cosmetic portfolio. If you’d like to explore custom formulations, better understand ingredient performance, or differentiate your offering with unique actives, our technical team is here to help.
Get in touch to discuss your next innovation.
Written by Norman Lowe, June 2025
