D4 Ban Countdown Begins: Ethyl Silicone Oil Industry Faces Compliance Upgrade Window

The ethyl silicone oil industry is facing significant compliance pressure in 2026. On January 12, 2026, China's National Medical Products Administration announced the inclusion of cyclotetrasiloxane (D4) in the prohibited list of cosmetic ingredients, effective January 1, 2028. Although this regulation has a transition period, its ripple effects are already being felt throughout the ethyl silicone oil supply chain.

Why D4 is Being Banned

D4 (octamethylcyclotetrasiloxane) is a cyclic siloxane that has long been used in cosmetics as a volatility and spreadability regulator. However, mounting toxicological research indicates that D4 has persistence, bioaccumulative, and reproductive toxicity properties. The EU included it in the REACH SVHC (Substances of Very High Concern) list as early as 2018. China's inclusion of D4 in the banned cosmetic ingredient list marks further alignment of domestic cosmetic safety standards with international advanced levels.

D4 is a common byproduct or cyclic residue in silicone synthesis that is difficult to completely remove using traditional ethyl silicone oil production processes. Although the regulation allows for "technically unavoidable" impurities, it sets a strict limit: D4 content in cosmetics must be less than 0.1% (w/w). This means that ethyl silicone oil manufacturers must control D4 residues below 0.1% to access the cosmetics and personal care supply chain.

Direct Impact on the Ethyl Silicone Oil Industry

For ethyl silicone oil manufacturers, the impact of this regulation is direct. Ethyl silicone oil is widely used as a spreadability enhancer and volatile carrier in high-end skincare products, sunscreens, color cosmetics, and hair care products. If ethyl silicone oil products contain excessive D4 residues, they will directly lose market access to the cosmetics industry.

At the same time, ethyl silicone oil is gaining increasing market attention as a "low-cyclic" alternative within the silicone industry. Compared with methyl silicone oil, ethyl silicone oil generates fewer cyclic byproducts during synthesis, making it easier to meet cosmetic industry compliance requirements. This inherent advantage is translating into market opportunities for ethyl silicone oil in high-end personal care applications.

Compliance Redlines Drive Process Upgrades

Two main technology pathways are emerging to address the D4 challenge:

Pathway 1: Polymerization Process Optimization. Traditional acid-catalyzed or base-catalyzed equilibrium polymerization reactions, due to their thermodynamic equilibrium nature, inevitably generate cyclic byproducts. By using highly active, highly selective catalyst systems or non-equilibrium polymerization processes, cyclic formation can be suppressed at the source. The photo-thermal synergistic catalytic polymerization patent published in early 2026 represents an important exploration in this direction.

Pathway 2: Deep Purification Treatment. For already synthesized ethyl silicone oil products, post-treatment processes including short-path molecular distillation, supercritical extraction, or thin-film evaporation can forcibly remove residual D4 and other low-molecular-weight cyclics. Although such processes increase energy costs, they serve as a final "quality insurance" for production lines that cannot solve the cyclic problem at the source.

Green Manufacturing Becomes Competitive Imperative

Driven by carbon neutrality goals, the ethyl silicone oil industry is accelerating its green transformation. Specific initiatives include:

• Low VOC Production: Process optimization to reduce volatile organic compound content below 0.1% to meet stringent requirements for food contact and medical-grade materials.

• Bio-based Raw Material Exploration: Some manufacturers are exploring plant-derived ethyl groups to replace traditional petroleum-based raw materials, reducing carbon footprint by approximately 40%.

• Continuous Production Processes: Adopting continuous production processes to replace traditional batch production improves unit capacity and, more importantly, significantly enhances batch-to-batch stability through constant reaction parameters.

Opportunity for Compliant Enterprises

For compliant, high-quality enterprises, the D4 ban represents a "market consolidation" opportunity. As cosmetic brands strengthen supply chain audits, low-cyclic ethyl silicone oil will command higher price premiums. Manufacturers that previously relied on low-price competition without quality accumulation will be accelerated out of the market by the 2028 deadline.

At the same time, this policy is driving "quality upgrading" of domestic ethyl silicone oil. In the past, one of the biggest barriers to Chinese ethyl silicone oil exports was excessive cyclic residue levels. As domestic manufacturers increasingly invest in low-cyclic processes, domestic brands have the opportunity to capture larger market share in the high-end personal care raw material market.

Market Data Confirms Green Trend

Market data confirms this trend: low-volatility and reactive silicone grades currently influence nearly 46% of purchasing preferences, with quality-certified products accounting for approximately 12% of total usage across industries. This indicates that green compliance is transforming from a "bonus" to a "admission ticket," with manufacturers lacking relevant capabilities struggling to compete in the high-end market.