Application principle
1. After dissolving in water, HPMC forms a high-viscosity solution. Through hydrogen bonds and hydrophobic interactions in the molecular chain, it increases the system's viscosity, delays the sedimentation of sunscreen agents (such as zinc oxide and titanium dioxide) or oil components, and maintains the formula's uniformity.
2. HPMC forms a transparent and flexible film on the skin surface, wrapping the sunscreen agent particles. This reduces the penetration of ultraviolet rays and the agglomeration of zinc oxide/titanium dioxide and enhances the sun protection effect (UPF value).
3. HPMC's film-forming property can reduce the direct contact between sunscreen agents and the skin, lower irritation, and indirectly enhance the durability of the SPF value by delaying the photocatalytic degradation of zinc oxide.
4. HPMC forms a water-retaining gel layer. When moisturizers such as glycerin and hyaluronic acid are added, they can relieve the dryness and tightness that may be caused by sunscreen, especially suitable for dry skin
1. HPMC sunscreen additives are highly safe and have low irritation, making them particularly suitable for sensitive skin. Moreover, they do not contain organic solvents or synthetic polymers, which can reduce the risk of acne.
2. HPMC's functional diversity is "thickening + stabilizing + film formation." A single component achieves multiple functions. Simplifying the formula can reduce it to 2 to 3 types of additives.
3. HPMC is green, environmentally friendly and biodegradable, reducing the use of non-biodegradable components such as plastic microspheres. It can replace synthetic polymers like carbomer or polyurethane, lowering the environmental burden.
In combination with sunscreen agents:
Surfactant compatibility:
Dissolution method:
Anti-corrosion system compatibility:
HPMC is generally added to sunscreen in powder form. During the production process, it is first mixed and dissolved with an appropriate amount of water or other solvents to form a solution of a specific concentration. Then, it is evenly mixed with different components and processed through stirring, emulsification, and other techniques to make sunscreen.
HPMC does not have a sun protection function and will not directly change the sun protection performance of sunscreen agents. However, by improving the rheological properties and spreadability of sunscreen, the sunscreen agent can cover the skin surface more evenly, which helps the sunscreen agent to fully exert its effect. This indirectly enhances the overall sun protection effect of the product and ensures the stability and effectiveness of the sun protection index.
HPMC can form a film with a certain toughness on the skin surface, which has an auxiliary effect on improving sunscreen's water and sweat resistance. When used in combination with specialized water repellents, it can better enhance sunscreen's adhesion to the skin surface after contact with water or sweat and extend the effective sun protection time. However, it cannot completely replace professional water-repellent components.
