In today's thriving world of anime culture, figure production has become an important way for enthusiasts to express their passion. From the delicate features of Hatsune Miku to the resolute expression of Tanjiro from Demon Slayer, each figure carries the creator's dedication and the fans' emotions. In the figure-making process, demolding is particularly crucial, as it determines the precision and integrity of the final product. Silicone oil, as an efficient release agent, plays an indispensable role in this stage.

The chemical properties of silicone oil make it an ideal demolding material. Its main component, polydimethylsiloxane, has extremely low surface tension, allowing it to form a uniform molecular film on the mold surface. This film neither reacts chemically with the mold material nor effectively reduces the adhesion between the resin or plaster and the mold. When liquid resin is poured into the mold, the methyl groups in the silicone oil molecules align outward, forming a hydrophobic barrier that ensures the cured figure parts can be easily removed without damaging the details. Notably, the viscosity of silicone oil must also be carefully selected—low-viscosity silicone oil is suitable for spraying, creating a thinner film, while high-viscosity silicone oil is better for manual application on complex molds, ensuring every corner is covered.

In practice, using silicone oil requires precise techniques. Experienced figure makers first thoroughly clean the mold to remove any dust or residue, as even tiny particles can cause imperfections during demolding. Before application, the silicone oil should be shaken well, then evenly sprayed using a fine nozzle spray gun from a distance of about 30 centimeters, or gently wiped onto the mold's inner surface with a lint-free cloth. When spraying, maintain a steady motion to avoid excessive buildup in certain areas, which could lead to oil spots or uneven gloss on the figure's surface. For extremely fine details like strands of hair or weapon engravings, a dotting method can be used—applying diluted silicone oil with a fine brush for precise treatment. Many professional studios operate in temperature- and humidity-controlled environments, as high temperatures can cause the silicone oil to evaporate too quickly, while excessive humidity may affect curing.

The advantages of silicone oil demolding lie not only in its ease of use but also in its ability to perfectly preserve details. The flowing hair of anime characters, the delicate folds of clothing, and the intricate patterns on weapons—these micron-level features can all be fully reproduced under silicone oil's protection. Compared to traditional release agents, silicone oil leaves no white residue on the resin surface, reducing post-processing work. Additionally, silicone oil is heat-resistant, meaning it won’t degrade even when used with resins that require heat curing. Technicians from the renowned Japanese figure manufacturer Good Smile Company once revealed that when producing their Hatsune Miku series, they followed strict standards for silicone oil selection and application—each mold was sprayed three times and inspected twice before resin was poured, ensuring flawless results.

However, silicone oil demolding is not without its drawbacks. Excessive use can cause an "orange peel" effect on the figure's surface, affecting the painting outcome. Some low-quality silicone oils may contain volatile substances that pose health risks with prolonged exposure. Therefore, professional figure makers recommend using medical-grade or food-grade silicone oil and working in well-ventilated areas. Another common issue is that residual silicone oil may interfere with subsequent painting. The solution is to gently wipe the figure's surface with an alcohol swab after demolding before applying primer. Interestingly, some advanced hobbyists intentionally leave trace amounts of silicone oil residue, taking advantage of its hydrophobic properties to create special "water droplet effects" for realistic wet-looking scenes on rainy-day-themed figures.

With advancements in materials science, silicone oil demolding techniques continue to evolve. In recent years, nano-silicone oil emulsions have emerged, capable of forming thinner, more uniform films—ideal for ultra-detailed figure production. Some manufacturers have also introduced colored silicone oils that indicate treated areas during demolding, preventing missed or repeated applications. In line with environmental trends, biodegradable silicone oils are gradually entering the market. Though more expensive, they are favored by studios committed to sustainability. Notably, the rise of virtual YouTuber merchandise has brought new challenges—these characters often feature even more exaggerated hairstyles and accessories, demanding higher demolding precision and driving further optimization of silicone oil formulas.

From hobbyist creations to industrial production, silicone oil demolding has become an essential step in anime figure manufacturing. It is not just a technical method but also a craft tradition. In a long-established figure shop in Tokyo’s Akihabara district, the owner, Mr. Yamada, has insisted on applying silicone oil by hand for forty years, believing that "machines cannot replace the human finger’s sensitivity to mold temperature." Perhaps it is this relentless pursuit of perfection that allows two-dimensional characters to be flawlessly recreated in three-dimensional form, continuing to tell their stories in fans’ display cabinets. In this world driven by passion, silicone oil is like an unsung magician, helping creators turn imagination into tangible reality.