投稿査読論文
ロングセラー・ブランドに向けた製品デザインと開発プロセス
2025 年 45 巻 4 号 p. 333-341
詳細
2025 年 45 巻 4 号 p. 333-341
This study aims to understand the product development process that integrates product design while maintaining brand consistency over time. For long-term brand survival, sustaining consistency and fostering innovation to continuously adapt to market changes has been recognized as essential. However, there has been limited understanding of how product design contributes to longevity within the development process. To address this gap, we reviewed previous studies on long-selling branding and universal design, analyzing the development process of two long-selling Otsuka Pharmaceutical products. Our case study analysis identified eight key phases common to both products: 1. research, 2. insight, 3. essentialization, 4. exploration, 5. development, 6. universalization, 7. diffusion, and 8. extension. The discussion highlights that product design aligned with sustainability and innovation can be realized when essentialization and universalization are adequately incorporated into the development process.
本研究の目的は，長い年月を経ても一貫性を保ちうる製品デザインを組み込んだ製品開発プロセスについての理解である。ブランドの長期的な存続には，ブランドの一貫性の維持と市場環境に継続的に適応するための革新の必要性が指摘されているが，それが可能となる製品デザインを組み込んだ開発プロセスについて理解が不足している。そこで，ロングセラー・ブランド化や普遍的なデザインに関する先行研究レビューを行った上で，同一企業による2つのロングセラー・ブランドの開発過程について分析した。事例分析の結果，共通する重要なプロセスが，1．研究，2．洞察，3．本質化，4．探索，5．開発，6．普遍化，7．普及，8．拡張の8つにまとめられた。特に，開発プロセスでの本質化と普遍化が満たされることで，維持と革新に適した製品デザインとなることが示された。
This study focuses on how product design enables brands to become long sellers. Building strong brand values supports long-term survival (Aaker, 1996). To achieve this, brands must maintain consistency (Keller et al., 2002) and innovate to adapt to evolving market environments (Türe & Ger, 2016). Specific methods include forming brand bonds through advertising, maintaining freshness (Aoki, 1998), and reevaluating brand elements under the guidance of brand gatekeepers (Preece et al., 2019).
Certain aesthetic elements are also shared in product design. Pittard et al. (2007) identified a universal preference for the golden ratio, and Machado et al. (2015) found that logos incorporating natural elements—such as flowers, fruit, animals, and landscapes—strongly influenced consumer emotions. Haines-Gadd et al. (2018) highlighted design elements that enhance the emotional durability of products as essential, while Foroudi et al. (2014) emphasized that brand distinctiveness also depends on unique, identifiable characteristics. Although these studies highlight lasting design features considered during product development, limited research addresses how emotionally and competitively durable product designs are created and finalized in the development process (Goworek et al., 2020). Therefore, this study explores how the development process incorporates product designs that maintain consistency over time.
Although the definition of product design has evolved over time (Luchs et al., 2016), based on Bloch (2011), this study defines product design as “the form characteristics of a product that provides utilitarian, hedonic, and semiotic benefits to the users.” This study focuses on the symbolic and interpretive value (Van Rompay et al., 2009) of design and assumes users read essential information—such as brand origin, category, purpose, and use—from product design (Monö, 1997). As a cross-functional process influenced by economic, aesthetic, technical, and commercial constraints (Borja de Mozota, 2003), design requires management throughout the entire development cycle (Anders, 2000). This study analyzes the entire product development process to understand how product design contributes to creating long-selling products that withstand both maintenance and change. Through case analysis, it examines how such products are shaped during development. This approach clarifies how companies that implement marketing strategies not only manage the post-launch product life cycle (Anderson & Zeithaml, 1984) but also plan long-term market adaptation from the design stage. To clarify the terminology used in this study: “product design” refers to a product’s form characteristics (narrow definition); “product development” refers to planning and creating a product; and “product development process” refers to the series of steps from research to market launch. “Design process” (broad definition) refers to the process from needs research and idea generation to productization (Luchs et al., 2016) and is considered part of the overall product development process.
Aoki (1998), through case studies of long-selling brands, identified that building and sustaining such brands requires two key strategies: actively responding to market changes—particularly in usability and advertising—while preserving core identity elements that shape a strong brand image. Five foundational requirements for long-selling brands were also identified: 1) clear core benefits, 2) superiority through proprietary technology, 3) effective benefit communication, 4) consistent identifiers, and 5) proactive market responsiveness. Similarly, Preece et al. (2019) found that long-term brand survival depends on balancing continuity and change, incorporating risk, excitement, and innovation to sustain interest while using existing brand knowledge to maintain familiarity. As both studies suggest, brand identity must evolve without being compromised, which requires designing a resilient identity from the outset. Aoki (1998) noted that Otsuka Pharmaceutical’s Pocari Sweat became a long-term seller by repositioning in peripheral markets, while unchanged content and packaging—along with its color, logo, and package—reinforced brand associations.
2. About long-lasting designRobustness requires not only visibility but also brand strength that endures change and avoids being overshadowed by others. Keller (2012/2015) identifies six criteria for brand element design: 1) memorability, 2) meaningfulness, 3) likability, 4) transferability, 5) adaptability, and 6) protectability. Design elements such as naming, packaging, colors, and logos play a key role in forming a strong identity for tangible, non-durable consumer goods including food (Ogawa, 2010). For instance, many long-selling products feature instantly memorable symbols on their packaging, while strong identifiers such as color and logo support brand extension beyond initial market success (Ogawa, 2010). Distinctive color use effectively establishes brand image. Creative color choices—such as yellow for Calorie Mate and blue for Pocari Sweat—are core to package design (Shirao et al., 2014). These elements convey meaning and symbolic value, shaping brand image from the outset. Since they are difficult to modify post-development, consistency is essential (Ogawa, 2010). Therefore, this study focuses on these elements, as they are directly linked to a product design’s ability to endure brand maintenance and change.
This study conducts a case analysis of a long-selling product’s development process from the perspective of product design requirements. After outlining the product development activities in chronological order, these activities are abstracted and modeled. The development process is examined through several phases, from inception to market offering and management. For instance, in the stage-gate decision-making model, decisions occur in five steps: opportunity identification, design, testing, introduction, and profit management (Urban & Hauser, 1980). A representative model of the design process is the Double Diamond (Design Council, 2005), which includes Discover, Define, Develop, and Deliver. The vertical axis represents the number of options, while the horizontal axis represents time, illustrating divergence and convergence in design. Drawing on these models, this study organizes the analyzed process into several distinct phases.
2. The subject of case analysis and dataThis study analyzes the product development process of Otsuka Pharmaceutical, a company with several long-selling brands. Otsuka’s products were selected for case analysis for two main reasons. First, both target brands—Pocari Sweat and Calorie Mate—have remained on the market for approximately 40 years and are considered successful examples of brands that maintained strong value by shifting their market positioning in response to environmental changes (Japan Marketing Association, 2018). Second, the long-selling nature of these brands was not incidental but a core premise of their development process. As discussed below, intentional strategies in design and development prior to launch likely contributed to their long-term success.
3. Outline of Otsuka PharmaceuticalOtsuka Pharmaceutical Co., Ltd. was established in 1964 as a separate sales division of Otsuka Pharmaceutical Factory, founded in 1921. The company’s corporate philosophy is “Otsuka-people creating new products for better health worldwide,” and its main businesses are the “Pharmaceutical Business” and “Nutraceutical Business” (Otsuka Pharmaceutical, n.d.-e). These account for 66% and 25% of the company’s scale, respectively (Otsuka Pharmaceutical, n.d.-c, p. 40). A key marketing feature is the authority held by the Product Marketing Manager (PMM), who oversees decision-making and brand management. This paper introduces the two brands analyzed in this case study: Pocari Sweat, a functional beverage, and Calorie Mate, a functional food. These were released in 1980 and 1983, respectively (Otsuka Holdings, 2020b, p. 4). Their sales volumes were 2,827 and 430 million cases, respectively (Otsuka Holdings, 2020a, p. 8) (Table 1).
Product overview
Source: Otsuka Holdings. (2020a, p. 8; 2020b, p. 4), modified by the author.
Pocari Sweat began as a high-priced sports drink for athletes before being popularized as a general health drink (Katayama, 1987, p. 136). Due to market limitations, the company recognized that a sports drink alone would not grow and aimed to develop a health beverage that addressed broader health needs, including mental well-being. In addition to functionality, this required creating a new flavor (Katayama, 1987, pp. 143–144).
(2) Creation of the essential ideaDrawing from daily R&D and pharmaceutical work, the team gained insight into social and physiological needs, such as the prevalence of sweetened beverages and the demand for a drink optimized for the human body. This led to the core idea: a beverage with the same osmotic pressure as human body fluid. Although the utility of this concept is evident, its realization and widespread adsorption required several years of development.
(3) Exploring realization, product specifications setting, and developmentTo create a healthy drink, the sugar content was significantly reduced, defying the common belief that drinks with approximately 12% sugar taste better. Inspired by the subtle saltiness in Ako’s shiomi manju, numerous prototypes were developed to achieve a pleasant balance of sweetness and saltiness. Ingredient ratios were adjusted based on the assumption that several people would drink it as an alternative to water when slightly sweating (Katayama, 1987, pp. 145–147). Eventually, through prototyping in various scenarios, the researchers, technical director, and president settled on a mild sugar concentration suitable for daily consumption (Katayama, 1987, p. 148; Otsuka-plus1, n.d.-b, p. 2). Due to its unfamiliar taste, the drink was initially unpopular even within the company, and early consumers complained it was too weak (Otsuka-plus1, n.d.-b, p. 2). To address this, the company used its authority as a pharmaceutical manufacturer to promote the product with clear, scientific explanations of its medical benefits (Katayama, 1987, pp. 155–156).
(4) Universal valueThe concept introduced for Pocari Sweat describes it as a “beverage of sweat,” a “beverage of ions,” or a health drink that replenishes water and electrolytes (ions) lost through perspiration (Otsuka Pharmaceutical, n.d.-f). This clearly expresses its function and reflects the core idea of a beverage matching the osmotic pressure of human body fluids. It is suited for various contexts and appeals to universal values that transcend specific situations or historical backgrounds.
(5) Naming, package design, color, and logo settingThe name Pocari Sweat also enhances its universal value. “Pocari” has no specific meaning but conveys a bright, soft, and friendly image that is easy to remember. “Sweat” emphasizes its scientific relevance for people in sweaty conditions and evokes refreshment (Katayama, 1987, pp. 156–157). The Otsuka Group has a tradition of choosing memorable, simple names—such as Oronamin C and Bon Curry—that gain strength beyond logic and pose barriers for competitors once established (Katayama, 1987, pp. 156–157). Names that feel naturally familiar and comforting contribute to universal value, unrestricted by time or place. The use of blue—taboo in the food industry—and white in the packaging symbolizes the idea that body water resembles seawater and reflects the belief that all life originated from the sea (Katayama, 1987, pp. 154). The shape and size of the container were regularly refined to respond quickly to changing drinking habits and social awareness; however, the core graphic design remained unchanged, reflecting a universal concept that remained relevant over time (Nikkei Design, 2013, pp. 8–13). This design, created by graphic designer Helmut Schmid, features white wave lines symbolizing the product’s function, derived from Pocari Sweat’s absorption speed graph (Japan Creators, 2022). Designer Masashi Murakami described it as a model package design, with a blue-and-white logo recognizable from a distance and a minimalist package that relies solely on typography (Japan Creators, 2022). Here, “symbolic” refers to expressing the product’s features and uniqueness through memorable shapes and marks. A symbolic identity strengthens brand stability and enhances advertising flexibility (Japan Creators, 2022). Moreover, long-lasting designs that adapt across contexts eliminate redesign costs, making design investment more efficient (Nikkei Design, 2013, pp. 14–15).
(6) Diffusion of product valueAt launch, Pocari Sweat was unfamiliar to consumers, prompting extensive educational efforts on the importance of hydration. Full-page newspaper ads, televised seminars, and nationwide commentary by doctors promoted the concept of a “health drink” (Nikkei Business Daily, 1983, p. 20). Samples were distributed to opinion leaders—including doctors, nutritionists, pharmacists, public figures, and high school baseball players—along with questionnaires. The rise of the “do-sports market” was interpreted as growing health awareness, and the product was promoted across diverse audiences and usage scenarios (Otsuka-plus1, n.d.-b, p. 2). Until 1979, the sports drink market remained under 1 billion yen (manufacturer shipments). In 1980, Pocari Sweat alone recorded 9.5 billion yen in sales, reaching 25 billion yen in the hot summer of 1981 (Nikkei Business Daily, 1982, p. 1).
(7) Extension in response to the times and environmentsAccording to Shinichi Asami of PMM, the iconic image of teenagers sweating—often used in Pocari Sweat ads—reflects the product’s foundation in body composition research: “It is the result of honest research on body components, thus, it is difficult to change the taste. The peace of mind of not changing is the biggest secret of longevity” (Nikkei Trendy, 2017, p. 126). This approach relies on human nature. He also noted, “Teenagers as well as adults who were once young people will recall their adolescence” (Nikkei Trendy, 2017, p. 126), emphasizing the universal emotional appeal. Even as scenes shifted to address heatstroke or support desk workers, the product’s identity remained intact. Former president Akihiko Otsuka stated, “Social and health issues change with the times. However, the composition of the human body does not change, so the basic evidence can be applied” (Nikkei Business, 2021). Upon entering the Indonesian market, where sports and sweating were less common, the brand faced challenges; however, it ultimately gained success as a drink to “heal dehydration after Ramadan,” an unintended yet effective reinterpretation (Kawabata, 2021). Despite this adaptation, the packaging remained unchanged, demonstrating the robustness of the product design.
5. The case of Calorie Mate (1) Insights based on research findings and social environmentBelieving oral nutritional intake to be more beneficial for patients than intravenous drips (Otsuka Pharmaceutical, n.d.-a), Otsuka Pharmaceutical developed Hinex-R, a medical-use liquid food, in 1979. This became the foundation for Calorie Mate (Otsuka Pharmaceutical, n.d.-b). Inspired by “space food,” the product aimed to be easily digestible, nutritionally complete, compact, and packaged for convenient consumption (Otsuka Pharmaceutical, n.d.-a).
(2) Creation of the essential ideaAs disordered eating habits became a societal concern, Calorie Mate was developed by applying medical nutrition food to supplement healthy individuals (Otsuka-plus1, n.d.-a). Its key feature is a “balanced nutrition food” that “allows you to easily take the five major nutrients essential for maintaining good health in a balanced way, anytime, anywhere” (Otsuka Pharmaceutical, n.d.-b). This essential value was derived from prior product research and insights into societal needs.
(3) Exploring realization, product specifications setting, and developmentDevelopment was challenging and required emulsification technology to prevent ingredient separation, as well as uniform mixing of multiple nutrients (Otsuka Pharmaceutical, n.d.-b). After six years—three for emulsification and three for balancing taste and nutrition—the product was completed (Otsuka Pharmaceutical, n.d.-a). Its structure allows easy calorie calculation: each block contains 100 kcal and maintains consistent taste and nutrition even when divided (Otsuka Pharmaceutical, n.d.-a).
(4) Universal valueIn an interview, Mr. Iwasaki, PMM of Calorie Mate, explained that the product was designed to support nutritional balance for people of all ages by offering various flavors and formats that harmonize taste and nutrition. He emphasized its goal to become a universally loved product over time (Walker plus, 2022).
(5) Naming, package design, color, and logo settingThe name Calorie Mate was chosen because it contains the five major nutrients in a balanced form, with “mate” meaning “friend” (Otsuka Pharmaceutical, n.d.-g). The package design was created by art director Gan Hosoya and typographer Tadasu Fukano. The classic lettering adds originality, the yellow coloring stands out and allows for variation, and nutritional content is listed in block letters on the front to reflect its identity as a balanced food (Good Design Award, 2014). Logo colors were matched to each flavor’s sensory impression, and the yellow packaging was designed to be visible even under sunset lighting (Walker plus, 2022). The symbolic design—with its vivid yellow and elegant logo—remains highly recognizable in stores, contributing to its universal appeal across different times and contexts (Brain, 2015).
(6) Diffusion of product valueWhen Calorie Mate was first launched, its taste was not well received internally. However, the company distributed samples to athletes and held explanatory meetings. This led to rising popularity among athletes and support from doctors and nutritionists (Otsuka Pharmaceutical, n.d.-d). The sales promotion team also provided nutritional information to assist retailers (Nikkei Business Daily, 1984, p. 16).
(7) Extension that adapts to the times and environmentsIn response to the diet boom, the company introduced breakfast/diet and chocolate flavors for high school girls (Otsuka Pharmaceutical, n.d.-d), a maple flavor for working women, and samples for students preparing for entrance exams, along with a commercial supporting exam-takers (Nikkei MJ, 2010, p. 3). According to PMM Iwasaki, the brand saw renewed growth in 2022 with the launch of a vanilla flavor familiar to children and older adults, meeting new needs for home-use nutritional foods (Mynavi News, 2022). Across these extensions, the core elements—five essential nutrients, packaging, naming, and base colors—remained unchanged. Meanwhile, variations in flavor, logo color, appeal scenes, and target audiences allowed the brand to evolve while maintaining its identity.
This study modified the standard product development model based on observed case activities, integrating key elements of the Double Diamond design model to construct a long-selling product development framework.
The process includes the following stages: (1) research on humans and materials, (2) social insight, (3) identification of essential human-centered ideas, (4) exploration of realization methods, (5) specification setting and development, (6) creation of universally valued products, (7) education and diffusion, and (8) extension of targets and usage scenarios (Table 2).
Activities related to the eight stages of long-selling products in case studies
Based on the product development framework, this model incorporates Double Diamond’s idea divergence–convergence flow while adding essentialization, universalization, and related research and extension activities to represent the full development process for long-selling products, as modeled in Figure 1.
Process model for long-selling product development
Unlike Double Diamond, this model places research before insight. Routine knowledge accumulation on the human body, emotions, and materials supports essentialization without narrowing options. In the insight phase, focus areas are defined. Exploration and development mirror Double Diamond: exploration expands ideas; development narrows and realizes them. Extension involves adapting to change and sustaining freshness. In Figure 1, ▷ indicates convergence, ◁ divergence, □ continuity, and 〇 moments defining unchanging elements.
Essentialization and universalization are key to building long-selling brands. Essentialization means identifying core human values; universalization involves creating appealing, context-free products. Pocari Sweat’s value lies in matching the body’s ion balance; Calorie Mate’s in providing five essential nutrients. Both offer optimal, timeless, human-centered solutions.
Since essentialization provides a clear focus, it helps ease the difficulty of convergence noted in the Double Diamond model (Da Silva et al., 2020). In universalization, appeal across contexts and time enhances emotional durability, a key factor in long-term success (Haines-Gadd et al., 2018).
Several product designs resist becoming outdated. Examples of enduring classics include Weber barbecue stoves, Zippo lighters, rear-engine Porsches, and Beethoven symphonies (Bloch, 1995). Their success stems from symbolic meaning, nostalgia, efficient form aligned with function, and designs that match innate preferences (Bloch, 1995; Fishwick, 1985; Holbrook & Schindler, 1989). This case study reveals several design ingenuities that avoid becoming old-fashioned. For Pocari Sweat: a pleasant, light taste; a health drink suited to a broad audience; a familiar, comforting name; and a symbolic logo and color visible from afar. For Calorie Mate: balanced nutrition anytime, a classic logo, taste-matched colors, and packaging that maintains visual consistency. These features communicate longevity through simplicity, familiarity, and universal appeal.
2. Essentialization and universalization in long-selling productsEssentialization clarifies fundamental human desires before they become concrete needs. It identifies what is indispensable, while universalization assembles these essentials into products adaptable across time, users, and scenarios. In long-selling products, essential ideas gain universal value during development. This value remains stable despite social or environmental changes, making design updates unnecessary. Instead, by aligning communication with evolving societal and consumer contexts, brands can maintain relevance and continue offering the same product in new environments.
3. Differences in the design processThe intent of the development model in this study differs from other design approaches. Design Thinking (DT) seeks optimal, environment-adapted solutions (Kelley et al., 2001/2002), while Innovation of Meaning (IoM) (Verganti, 2009/2016) aims for cultural paradigm shifts through new meaning. In contrast, long-selling product development focuses on creating essential, universally needed products. DT shares the universalization process—divergence and convergence from insight—but is less effective in extracting core human values and often favors individualized outputs. IoM is rooted in the vision and spreads meaning through exhibitions, aligning with the research, insight, essentialization, and diffusion phases in Figure 1. However, as IoM depends on cultural trends and subjective preferences, its value may lack universality. Even when followed by human-centered design improvements (Norman & Verganti, 2014), IoM-based products remain tied to trends and identity narratives. In contrast, long-selling products may initially lack strong stories or emotional appeal but fulfill essential human needs and adapt across environments through consistent communication efforts.
4. Impact of essentialization and universalization on decision-makingThis study explores how essentialization and universalization influence decision-making in both development and consumption behavior. In development, essentialization enables progress without narrowing the target by relying on human nature. With a clear axis, identity remains intact, and the product can be summarized as universal. Since identity is not defined by a specific audience, extending the target rarely necessitates design changes. In consumer behavior, universalization may improve communication efficiency. Robust, symbolic identities—expressed through packaging, naming, logos, and colors—are more effectively perceived. Essentialized values grounded in human nature are more likely to persist across time and contexts.
A key feature of this model is recognizing the need for both essentialization and universalization. Essentialization preserves value across contexts, while universalization prevents obsolescence from cultural or trend changes. Their integration supports the development of long-selling products.
This study deepens our understanding of a product development process that maintains design consistency over time by emphasizing two fulcrums: essentialization and universalization. While Preece et al. (2019) examined long-selling brand robustness through film production, this study focused on tangible food products. Whereas previous research emphasized brand element reconfiguration, this study highlights the role of initial product design—embedding essential human value, flavor, symbolic colors, and logos suited to varied contexts.
Practical suggestions are as follows: 1. Look beyond trends and environments to gain deeper insight into unchanging human nature; 2. When defining product identity, relate it to enduring human needs that remain relevant despite external changes; 3. Pursue optimal realization methods without compromise, commercialize with precise specifications, and reduce long-term costs by minimizing later revisions; 4. Invest in design to create a symbolic identity that supports product extensibility; 5. For products with new value, conduct patient educational and promotional efforts to secure a lasting market position; and 6. Stay responsive to societal trends and express the product’s universal value in modern contexts through appropriate communication.
Understanding of the product development process behind long-selling brands with consistent product design over time has been limited.
To address this, we analyzed the development process at Otsuka Pharmaceutical, which is known for its long-selling products. Eight common and essential phases were identified: 1) research, 2) insight, 3) essentialization, 4) exploration, 5) development, 6) universalization, 7) diffusion, and 8) extension.
This study contributes by clarifying how long-selling products are developed—extracting shared activities through case studies and modeling them. Concrete development activities were highlighted, and practical suggestions were provided to support the application. The discussion showed that combining essentialization and universalization enables product designs that support both consistency and adaptability.
However, limitations remain. The interaction between essentialization, universalization, and target scope requires further study. The process is also not linear—interactive and iterative dynamics should be considered. Future work should examine the roles of actors, management strategies, and design development methods.
Additionally, knowledge accumulation in the research phase may involve approaches beyond pharmaceutical research, presenting further avenues for investigation.
This research was supported by joint research funding from the Research Institute, Kanazawa Seiryo University. We are sincerely grateful to the anonymous senior editor and two reviewers for their valuable comments, as well as the journal office for their appropriate checks and helpful suggestions, all of which significantly improved the quality of this paper. We extend our sincere gratitude to Associate Professor Yoshida Mari. This paper was written in Japanese, roughly translated into English using DeepL, and carefully edited by the authors. We would like to thank Editage (www.editage.jp) for English language editing.
This study used secondary data from sources cited throughout the manuscript.
Hikaru Makino
Hikaru Makino is an Associate Professor in the Faculty of Business Administration at Kindai University. He holds a Ph.D. in Business Administration from Ritsumeikan University. Before his current role, he was an assistant professor, lecturer, and associate professor in the Faculty of Economics, Kanazawa Seiryo University. His primary research interests are Behavioral experience and embodiment.
Mihiro Kobayashi
Mihiro Kobayashi is an assistant at the Shiranuhi Immigration Lawyer Office. He has been working part-time as a research assistant at the OIC Research Office, Research Department, Ritsumeikan University since August 2024. He holds a master’s degree in business administration from Ritsumeikan University and completed his doctoral programs. His primary research field is Marketing Communication.
