[Mid-sized Business Mastery Series] ⑤ Hanil Cement's Seosin Seok... The 'Mortar Doctor' Who Overcame Failure

Creating the Best Product Hard to Rebirth, Respected as the 'Father of Horizontal Mortar' in the Industry
"I Didn't Make It Alone, It Was Made Together with Team Members" Humble Thanks to Colleagues

"Do not give in to the fear of failure and abandon challenges."

Known as the 'Mortar Doctor' and the 'Father of Self-Leveling Mortar,' Seosin-seok, the top mortar expert and Quality Management Team Leader at Hanil Cement Technology Research Institute, said the biggest problem for researchers is "fear of failure," explaining, "It is succumbing to fear and not challenging the research reports painstakingly created with sweat and effort, letting them die without trying."

Seosin-seok, Head of Quality Management Team (Manager) at the Technology Research Institute of Hanil Cement, is explaining the performance test of tile adhesive mortar.
[Photo by Kim Jong-hwa]

Team Leader Seo graduated from the Department of Chemical Engineering at Chungnam National University and joined Hanil Cement Central Research Institute in Daejeon in January 1997, dedicating 27 years solely to research. As a master's degree holder, he got married right after joining and lived near his family home close to the central research institute in Daejeon, making commuting easy. He recalled that a senior researcher once assigned him the task of analyzing foreign substances floating on concrete. After diligently preparing and reporting the findings, his seniors praised him, and he found the work enjoyable.

However, in October the following year, the cement R&D team was relocated entirely to Hanil Cement's factory in Danyang, Chungbuk, which brought difficulties. His wife, who was raising their 10-month-old daughter at the time, struggled with living in the factory housing isolated from the city. Moreover, Seo was often exhausted from work and would collapse into sleep as soon as he got home. For family harmony, he requested a transfer back to the central research institute four years later, and the company accommodated this, stabilizing their life again.

Once life stabilized, work became enjoyable again. The products he led in developing, such as functional cement process improvements responding to changes in the building environment and new functional Remital products, received positive evaluations within the company. Market responses were enthusiastic, and he felt exhilarated as customer feedback came directly. Eventually, every product he made received such strong reactions that it was almost intimidating.

Best-Selling Manufacturer in the Mortar Industry

Commemorative photo with colleagues at the Daejeon Research Institute of Hanil Cement after the sports competition in September 2004. The person in the center of the front row is Team Leader Seosinseok.
[Photo by Seosinseok]

Starting with a clay brick adhesive product to prevent efflorescence, he developed most of the best-selling products known in the mortar market, including exterior wall insulation adhesive mortar, lime-based mortar, functional ceramic mortar, gypsum-based mortar, eco-friendly high-performance tile adhesive, high-performance cement-based grout for geothermal heat exchangers, concrete slab upper protection floor mortar, interior quick-drying self-leveling mortar, outdoor surface repair Remital, ultra-fast setting blended cement, and quick-drying premium floor mortar.

Although now widely recognized as the industry's top 'Mortar Doctor,' he also has indelible scars from failures. These mistakes were especially painful as they occurred during his successful rise in the cement industry when his skills were acknowledged by all.

In 2008, in his 11th year at the company, after about two years of research, Seo developed and commercialized Korea's first gypsum-based self-leveling (floor mortar) eco-friendly product, widely used in Europe. It was recognized for its revolutionary performance in preventing floor lifting and was applied to premium apartments rarely seen in provincial areas at the time. However, during the floor finishing process, the gypsum-based mortar's inherent material properties caused low adhesion during kitchen floor tile installation, resulting in tiles not adhering well and requiring full repair and reinforcement of the tile installation surface.

The product, praised by the industry as "too good," caused significant losses to the company when problems appeared at the first construction site. The company had to bear hundreds of millions of won in repair and reinforcement costs for the tile installation area, and Seo was disciplined. After this painful experience, he improved the product by mixing functional materials within about a month, but the market response was cold. It took several more years for the product to be recognized again as excellent and become widely used.

"Confidence in an Excellent Product Led to a Premature Release..."

Hanil Cement Yeoju Plant and the Technical Research Center are adjacent. Team Leader Seoshin-seok posed in front of the mortar piled up in the yard of the Yeoju Plant for the product launch.
[Photo by Kim Jong-hwa]

He recalled, "The incident occurred because we failed to recognize the subtle melting drawback of gypsum-based mortar. We should have conducted more sample pours and pilot constructions and observed the product for an additional 1-2 years before releasing it to the market. However, we were overconfident in the product's excellence and rushed the launch, which was a mistake."

By reversing the manufacturing process, they identified the problem within just a week, but the youthful arrogance and internal and external psychological pressure at the time left him with lasting fear. "I was dominated for a while by the fear that if something went wrong, it would be a huge accident." He became discouraged in all tasks and, when on-site, tried hard to check for potential problems with intense focus.

Then he suddenly realized, "There is no perfect product in the world. More advanced products will emerge. The attitude of continuous improvement is more important." He deeply reflected on himself and gained strong confidence to try again. He studied harder and published many papers.

Based on these experiences and lessons from failure, the paper he co-authored with colleagues, titled 'A Study on Causes and Reduction Methods of Lifting and Discoloration Defects in Floor Finishing Materials,' presented at the Architectural Institute of Korea in October 2009, became a hot topic with over 120 citations. Other major papers such as 'Analysis of the Correlation between Compressive Strength of Cement Mortar and Concrete (2018, Korean Concrete Institute, 143 citations)' and 'Basic Study on Material Properties of Hydraulic Lime Mortar (2005, Architectural Institute of Korea, 170 citations)' were widely referenced in academia. He also presented over 30 papers at major conferences, earning recognition as a mortar expert.

Comeback with the Development of the Final Plastering Material 'Self-Leveling Mortar'

Team Leader Seosin Seok is explaining the method of measuring the strength in front of the device that measures the strength of mortar.
[Photo by Kim Jonghwa]

His comeback product is the 'FS Series Mortar for Slab Protection' launched in 2010, which prevents lifting. The FS series, including FS 150, FS 300, and FS 400, divided by use for slabs, floors, and rooftops, became the industry's top best-seller following previous hits.

The tile adhesive 'Polyfix 1000' not only reduces dust but also cuts the weight of a single bag from 40 kg to 25 kg for premium plastering. This was not simply a reduction in volume to lower weight but a revolutionary product that mixed performance enhancers to maintain existing strength while reducing the raw material's weight for easier plastering work. It became a product all workers use as a standard.

One of the most beloved products is the 'Self-Leveling Mortar.' It is the perfected version of the self-leveling product that originated from the 2008 mistake and is Seo's best development. It is the best plastering material that automatically levels when poured on the floor without requiring the skill of plastering technicians and hardens without any lifting. Because it was reborn with enhanced crack control, adhesion, and strength, it is considered an unparalleled top product, earning Seo the honorary title 'Father of Leveling Mortar.'

Seo blushed and said, "I didn't make it alone; I made it with my team." This reveals his character. Usually, difficult research is avoided by researchers or they do not want to participate in results that take a long time, but he took on such tasks first and quietly carried them out. He said, "Communication and empathy are important in the research institute. There are times when colleagues' consideration is desperately needed," adding, "The harder it gets, the more I tried to lead by example and be considerate first, and at some point, the staff started following me."

18 Patents Registered Under the Name 'Seosin-seok'

Family photo of Team Leader Seosin-seok. The eldest daughter on the left got married last year and had a granddaughter.
[Photo by Seosin-seok, personal collection]

He has 18 patents registered under his name, has participated in various national projects, and conducted joint research with major domestic construction companies. For these achievements, he received awards such as the Excellent Contributor and the Korean Cement Association President's Award.

His family life is also happy. After Hanil Cement Technology Research Institute moved from Daejeon to Yeoju, Gyeonggi Province in 2018, he lived as a weekend couple but expressed gratitude to his wife who always takes care of him. In his mid-50s (born in 1970), he became a grandfather. His eldest daughter got married and had a granddaughter last year, who will soon celebrate her first birthday. Showing a video of his granddaughter taking her first steps, he fully displayed his doting grandfather side and even said he would quit smoking because he worried the smell might bother his granddaughter.

To juniors and colleagues working at the same company, he advised, "If you make a mistake or error, seek solutions by asking 'why'." He emphasized that by searching for the causes of mistakes and pondering them, "the exhilaration when those worries are resolved accumulates, developing new application skills, and before you know it, you become a master (expert) in that field."

◆Words from the Master

Having worked 27 years solely in research, just by looking at research reports submitted by employees, I can immediately grasp how much they have struggled and how they reached their conclusions. However, my experience and knowledge can sometimes act as a prejudice. Therefore, I always review employees' reports with the premise that 'I could be wrong too.' Products constantly evolve to meet customer demands. In the fierce research to develop better products, it cannot be just 'me.' Courage to objectively accept colleagues' concerns (research) is necessary.