Loved for Over 25 Years with 470 Million Units Shipped: Why Gunze's 'Unchanging Underwear' Continues to be Chosen Across Generations
To commemorate its 130th anniversary in August 2026, Gunze Limited has launched an archive LP series exploring the secrets behind its long-selling brand 'Kaiteki Kobo,' which has sold 470 million units by prioritizing unchanging comfort and quality.
📋 Article Processing Timeline
- 📰 Published: April 28, 2026 at 22:00
- 🔍 Collected: April 28, 2026 at 13:31
- 🤖 AI Analyzed: April 28, 2026 at 13:41 (9 min after Collected)
Gunze Limited (Headquarters: Kita-ku, Osaka; President: Toshiyasu Saguchi) will release monthly archive LPs starting today to commemorate its 130th anniversary in August 2026, unfolding the development stories of its long-selling brands. This project was born from a desire to thank long-time customers by helping them understand and appreciate their favorite products more deeply through reviews and brand stories.
In this release, a third-year PR representative explores the trajectory of a brand that defies industry common sense by being loved for decades, highlighting the 'obsession with comfort' and passion of the predecessors hidden behind its success.
The first installment features 'Kaiteki Kobo,' a brand loved for over 25 years since its debut with over 470 million units shipped. It is a long-selling brand boasting immense popularity among cotton lovers, centered on 100% high-quality cotton products.
■ 'Kaiteki Kobo' Defies the Industry Lifespan Theory
There is a theory that apparel brands have a lifespan of about 12 years, often requiring model changes every three years to sustain themselves. In contrast, Kaiteki Kobo has continued to sell for over 25 years. Without flashy advertisements and with packaging that hasn't changed for a quarter-century, it has still reached over 470 million shipments.
The true lifespan of a brand is determined by the emotional connection with customers and the long-term maintenance of high quality standards. By analyzing 2,479 reviews and 614 survey responses from Gunze Store, we discovered that underwear is not just clothing but a 'baton' passed down through generations and families.
■ 'Family Memories' Linked by Underwear: Insights from 2,479 Reviews
One symbolic comment came from a woman in her 30s: 'The package design looks like it's for grandmothers. But as someone with sensitive skin, I remembered my late grandmother loved Kaiteki Kobo all year round and mustered the courage to order it. I regret not buying it sooner; it is truly comfortable as the name suggests.'
Memories of a late grandmother moved the shopping cart of the next generation. This is not just one voice. A man mentioned buying a crepe shirt his grandfather used to wear, saying, 'I thought it was for elderly people. After trying it, I realized I should have bought it earlier! Perhaps my grandfather evoked my summer vacation memories.'
A review for a 90-year-old mother-in-law concluded: 'She has used it for decades and is so used to it that she doesn't want to use anything else. She is satisfied, saying "This is the one."'
This 'This is the one' encapsulates decades of trust. Surveys also revealed voices across generations: 'I can't forget the peace of mind on my skin when I first wore it' (30s woman), 'I trust it because it's been a favorite since my mother's time' (60s woman), and 'Thank you for continuing to make 100% cotton underwear. It is essential to my life' (60s woman).
Buying underwear while thinking of family members contains 'love' wishing for their well-being. This sentiment is passed down and moves the shopping carts of the next generation. This accumulation of 'sentiments that don't appear in numbers' is the true identity behind the 470 million units.
■ 'Kaiteki Kobo': A Brand Name Carrying the Underwear Physiology Lab
Why is it so trusted? The root lies in the 'Kaiteki Science Lab' located within the Miyazu Factory in Kyoto Prefecture.
Kaiteki Kobo was born in 1999, the start of the 'Lost Decade' after the bubble burst. Because it was an era of economic uncertainty, Gunze, which had developed underwear under the motto 'Gold Quality, Silver Price,' wanted to deliver 'unchanging peace of mind' for things that touch the skin directly. Thus, they opened the 'Kaiteki Kobo' physiology lab (now Gunze Kaiteki Science Lab) within the Miyazu Factory.
■ 'Fanatical Passion for Comfort' through Human Data and Biometric Measurement
Kazuhiko Fujimoto (Manager, Product Planning Section, Innerwear Division; 29 years with the company)
The development team struggled significantly with the mission to 'prove the comfort of underwear through data.' Looking across the industry...
In this release, a third-year PR representative explores the trajectory of a brand that defies industry common sense by being loved for decades, highlighting the 'obsession with comfort' and passion of the predecessors hidden behind its success.
The first installment features 'Kaiteki Kobo,' a brand loved for over 25 years since its debut with over 470 million units shipped. It is a long-selling brand boasting immense popularity among cotton lovers, centered on 100% high-quality cotton products.
■ 'Kaiteki Kobo' Defies the Industry Lifespan Theory
There is a theory that apparel brands have a lifespan of about 12 years, often requiring model changes every three years to sustain themselves. In contrast, Kaiteki Kobo has continued to sell for over 25 years. Without flashy advertisements and with packaging that hasn't changed for a quarter-century, it has still reached over 470 million shipments.
The true lifespan of a brand is determined by the emotional connection with customers and the long-term maintenance of high quality standards. By analyzing 2,479 reviews and 614 survey responses from Gunze Store, we discovered that underwear is not just clothing but a 'baton' passed down through generations and families.
■ 'Family Memories' Linked by Underwear: Insights from 2,479 Reviews
One symbolic comment came from a woman in her 30s: 'The package design looks like it's for grandmothers. But as someone with sensitive skin, I remembered my late grandmother loved Kaiteki Kobo all year round and mustered the courage to order it. I regret not buying it sooner; it is truly comfortable as the name suggests.'
Memories of a late grandmother moved the shopping cart of the next generation. This is not just one voice. A man mentioned buying a crepe shirt his grandfather used to wear, saying, 'I thought it was for elderly people. After trying it, I realized I should have bought it earlier! Perhaps my grandfather evoked my summer vacation memories.'
A review for a 90-year-old mother-in-law concluded: 'She has used it for decades and is so used to it that she doesn't want to use anything else. She is satisfied, saying "This is the one."'
This 'This is the one' encapsulates decades of trust. Surveys also revealed voices across generations: 'I can't forget the peace of mind on my skin when I first wore it' (30s woman), 'I trust it because it's been a favorite since my mother's time' (60s woman), and 'Thank you for continuing to make 100% cotton underwear. It is essential to my life' (60s woman).
Buying underwear while thinking of family members contains 'love' wishing for their well-being. This sentiment is passed down and moves the shopping carts of the next generation. This accumulation of 'sentiments that don't appear in numbers' is the true identity behind the 470 million units.
■ 'Kaiteki Kobo': A Brand Name Carrying the Underwear Physiology Lab
Why is it so trusted? The root lies in the 'Kaiteki Science Lab' located within the Miyazu Factory in Kyoto Prefecture.
Kaiteki Kobo was born in 1999, the start of the 'Lost Decade' after the bubble burst. Because it was an era of economic uncertainty, Gunze, which had developed underwear under the motto 'Gold Quality, Silver Price,' wanted to deliver 'unchanging peace of mind' for things that touch the skin directly. Thus, they opened the 'Kaiteki Kobo' physiology lab (now Gunze Kaiteki Science Lab) within the Miyazu Factory.
■ 'Fanatical Passion for Comfort' through Human Data and Biometric Measurement
Kazuhiko Fujimoto (Manager, Product Planning Section, Innerwear Division; 29 years with the company)
The development team struggled significantly with the mission to 'prove the comfort of underwear through data.' Looking across the industry...