Ritsubi Co., Ltd. (Location: Chuo-ku, Fukuoka City; President and CEO: Kazuyoshi Nishiyama), a company engaged in wholesale, planning, development, and import of cosmetics and beauty devices, will release "VC Serum 31," a high-concentration pure vitamin C serum, from the serum line of its beauty medical and aesthetic-inspired total care brand Mesoceutical®, on Tuesday, February 24, 2026.
Mesoceutical® is a brand that pursues "results-oriented skincare" based on insights from beauty medical and aesthetic practices. VC Serum 31 was created as a serum aimed at achieving higher efficacy by leveraging the formulation techniques cultivated to date.
*¹ Product stabilizer
*² To the stratum corneum
*³ Compared to our previous products
Mesoceutical Official Website: https://www.ritsubi.co.jp/mesoceutical/
Mesoceutical Official Instagram: https://www.instagram.com/mesoceutical/
Development Background
In recent years, vitamin C serums have become standard as an ingredient that can address a wide range of skin concerns, including tone-up, pore tightening, and improved firmness. However, there has been an increase in voices saying "I want to feel results faster" and "I feel my current care is not enough."
Mesoceutical® has focused on the "results-based experience" required in beauty medical and aesthetic practices, and has been developing serums that allow users to feel that effectiveness in their daily skincare routine.
Based on Ritsubi's knowledge accumulated over 15 years of research in developing pure vitamin C serums, the company pursued a balance of concentration, formulation, and usability. While considering the characteristics of pure vitamin C, which tends to be irritating, VC Serum 31 has achieved the highest class concentration⁵ in the aesthetic market through a formulation design⁴ that considers the burden on the skin.
*⁴ Individual differences exist in how irritation is perceived and felt
*⁵ As a pure vitamin C-containing serum in the aesthetic market. According to our research (as of January 2026)
Product Overview
Product Name: VC Serum 31
Content Volume: 15mL
Price: 17,600 yen (tax included)
Release Date: Tuesday, February 24, 2026
Features of VC Serum 31
31% Pure Vitamin C Formula - Highest Class High-Concentration Design in the Aesthetic Market
VC Serum 31 is a high-concentration serum containing 31% pure vitamin C. Pure vitamin C, which is known to produce results but is difficult to handle, is generally said to be quite irritating. VC Serum 31 has minimized the burden on the skin as much as possible, achieving the highest class concentration in the aesthetic market.
Formulation Design Using Proprietary "VCore-X™" Technology
The product adopts a water-free formulation*⁶ that does not use a single drop of water, and employs the proprietary amphiphilic technology "VCore-X™" that enables both hydrophilic and lipophilic properties of ingredients. By providing characteristics that are compatible with both water and oil, the formulation design focuses on allowing ingredients to penetrate firmly beyond the skin's lamellar structure.
The formulation design, which brings out the original power of pure vitamin C and considers even the process of blending into the skin, pursues a feeling of effectiveness that can be experienced in daily skincare.
Furthermore, the water-free formulation has achieved sustained ingredient activity*⁷. By adopting a simple formulation design that carefully selects only the minimum ingredients necessary for product development, the aim is to maintain a state where even pure vitamin C, which is inherently unstable, can easily retain its original power.
*⁶ Water-free formulation
*⁷ Product stability is maintained
Expected Effects and Skin Impression
Monitor results after one month of using VC Serum 31 morning and night
Physical sensations and impressions after monitoring:
- Pores*⁸ became less noticeable
- Improvement in dullness*⁸, enhanced transparency
- Improved firmness and smoothness
*⁸ Results based on our monitor survey. Individual differences exist, and the same effects and results are not guaranteed.
About Mesoceutical®
Mesoceutical® is a total beauty brand that aims to support beauty from both the outside and inside, based on beauty medical and aesthetic insights.
The brand develops four lines: R.CODE®, a high-function skincare line focusing on DNA; the serum line using special solvents that penetrate both water and oil; the biomask line featuring biomasks with approximately 20 times the water retention capacity of ordinary non-woven fabrics, impregnated with abundant active ingredients; and the inside line, supplements containing carefully selected ingredients.
These four lines support healthy beauty through daily accumulation by approaching both the external and internal aspects of the body, from skincare to inner care.
Company Overview
Company Name: Ritsubi Co., Ltd.
Location:
Fukuoka Head Office: KH22 Building, 1-15-6 Kego, Chuo-ku, Fukuoka City, Fukuoka 810-0023
Tokyo Head Office: Tokyo Fashion Town Building East Tower 8F, 3-6-11 Ariake, Koto-ku, Tokyo 135-0063
Representative: President and CEO Kazuyoshi Nishiyama
Established: April 1993
Business Overview: Import and wholesale of cosmetics and beauty devices / Product planning and development / Health foods / Mail order business
