Common questions about cellulose products and their applications Part 2: Application of cellulose in rinse-off formula
1. Using cellulose transparent paste (transparent hand soap, shower gel, shampoo), low temperature opaque, how to solve?
HPMC is widely used in hand sanitizers, shower gels and shampoos. It is generally difficult to be transparent at low temperatures. Currently, there is almost no HPMC on the market that can be used in systems containing surfactants and NaCl to achieve low temperature transparency.
The main reason is that at low temperatures (1 to 10 degrees), in the case of surface activity and NaCl in the system, the hydrophilic properties of HPMC are challenge and will precipitate from the system. Once the temperature returns to 15 degrees to room temperature, HPMC will be slow. Slowly re-forms the hydrogen bond network structure with water, dissolves again, and the system becomes transparent.
It is precisely because HPMC will precipitate a small amount at low temperature to have the performance of low temperature jelly, and it is difficult to apply it in a transparent system. In addition, the content of HPMC substitution groups (methoxyl and hydroxypropoxy) is different. It also determines the salt tolerance of HPMC, and the difference in low temperature precipitation, ie, jelly resistance.
For these transparent systems, such as hand soap, shampoo and shower gel, you can try HEC (250HHR PC). HEC does not have the characteristics of low temperature precipitation. It is only necessary to do proper compounding test with HEC in the initial stage of selection.
During the test, the two can be observed immediately. The surface active system and HEC are compound at room temperature, and will not precipitate at low temperatures, ensuring low-temperature transparency.
Most of the traditional anion activity and HEC compound performance is relatively good, and the amphoteric surface activity and non-ionic surface activity and HEC compounding will be challenging, there is a limit.
2. How to use cellulose in hand sanitizer, how to choose?
For transparent hand sanitizers, HEC is recommend, but the active system and HEC compound test are require. If the system is not compound, a small amount of colloid can be directly observe at the bottom of the cup;
In the case of opaque hand sanitizers, HPMC (E10M) is recommend, but the combination of epidermal activity and HPMC is also required. In addition, HPMC has an advantage: it can resist irritation and improve the mildness of hand sanitizer.
3. Use cellulose as a cleansing gel. When adding a table, what is the reason for some transparency?
Transparency is determine by the combination of surface activity and cellulose. Usually, hydroxyethyl cellulose is the most adaptable to the surface activity. In special cases, it may be necessary to adjust the ratio of surface activity to cellulose.
Maybe you have used a sex or pseudo-cationic auxiliary table. Hydroxyethyl cellulose and sodium cocamphoacetate or cocamide DEA/MEA do reduce the transparency. Cocamidopropyl betain is more than 6%. At this time, it may be necessary to choose a more suitable compounding ratio.
4. What are the advantages and disadvantages of surface-modified and unmodified hydroxypropyl methylcellulose in the thickening of soap-based systems? Hydroxypropyl methylcellulose is too strong in brush-based shower gel system. , use less viscosity, please give me any suggestions?
Hydroxypropyl methylcellulose (HPMC) surface modification and unmodified, there is no difference in the viscosity contribution of the soap-based system. The effect of thickening mainly depends on the molecular weight of HPMC, and the surface modification will only affect the dispersion. Process.
In addition, the different foaming capacity of HPMC will have different foaming effects on the system. The HPMC surface modification type is similar to HEC, and HPMC with surface hydrophobicity improvement has better dispersibility in cold water.
Untreated HPMC, such as Ashland HPMC, can be dispersed with a small amount of hot water, or dispersed in a polyol, and add to the soap-based system.
The use of hydroxypropyl methylcellulose (HPMC) in soap-based body washes, if it is a pure soap-based system, to reduce the feeling of brushing, low molecular weight HPMC, such as K35M, can be use. If it is a soap-based system, to reduce the feeling of brushing, you can choose E10M.
5. In the amino acid system facial cleanser, does the use of cellulose cause pan-thickness?
The specifics depend on the amino acid species used and the proportion of compounding. Generally, the system using pure amino acid activity, considering the characteristics of difficulty in thickening, can be considered to use HMHEC, that is, hydrophobically modified hydroxyethyl cellulose.
While thickening itself, it can also crosslink the surface to form viscosity and cohesion, and will not be thick. If it is a system of soap base and amino acid compounding, a part of the viscosity and hardness comes from the unneutralized free fatty acid, and it is indeed possible to make it thick.
Hydroxypropyl methylcellulose, which is more abundant in hydrophilic groups, can be consider to bind and disperse fatty acids for the purpose.
6. What effect does cellulose have on the use of 250HHR, ACULYN 60, DOE-120?
All are polyhydroxy structures, the difference is that the 250HHR main chain is hydrophobic cellulose and the main chain such as DOE-120 is hydrophilic polyethylene glycol. Theoretically, there is no conflict, especially in complex hard-to-thickening surface active systems. Synergistic thickening. If a single use requires a single addition to achieve the target viscosity, it may affect the skin feel or even jelly.
7. Does the activity increase the dissolution of HPMC in water, and is there any modified cellulose on the market?
Epidermal activity did not increase the dissolution of HPMC in water. On the contrary, they had a certain competitive relationship. HPMC had better performance with traditional anions. In some concentrations of amphoteric surfactant or nonionic surfactant aqueous solution, it may be from the system. Precipitate.
There are modified cellulose on the market, such as our HMHEC (cetyl hydroxyethyl cellulose), but this is a hydrophobically modified product. Its characteristics are that it has certain emulsification properties and synergistically stabilizes the emulsion system. At the same time, it provides a smooth and refreshing skin feel.
8. Which of the cationic celluloses has the best levitation force?
We have not compared the suspension capacity of different cationic cellulose (JR or LR). However, in theory, the production of cationic cellulose is generally made by using HEC and then quaternization.
Its main chain structure is similar to cellulose HEC, which belongs to polydextrose. The yield value is relatively low and should not have good suspension ability.
9. Can a product containing a cationic bactericide thicken with cellulose? If so, which cellulose?
Products containing cationic bactericides can be thicken with cellulose, and both non-ionic cellulosic products HEC and HPMC can be compound with cationic bactericides.
Which cellulose product is selecte specifically depends on the system of this product, is it a system with a high ethanol content, or a system containing a large amount of other types of polyols (glycerol, propylene glycol, etc.), which needs to be further confirm by the questioner.