The R&D Front Line vol.1 Aya Inoue


Overcoming challenges together with the customer to supply the ideal product at the ideal time

The surface of a computer hard disk is coated with a microscopically thin, 1- to 2-nanometer layer of lubricant to protect its surface. MORESCO boasts the leading share of the world market for such hard disk surface lubricants. Aya Inoue is a MORESCO employee who is involved in the research and development of hard disk surface lubricants, which are essential for increasing hard disk drive performance. We asked her about the theme of her research.

Aya Inoue

Research theme As disk capacities grow, surface lubricants are required to be thinner than ever before

I develop lubricants that are applied to protect the surface of the disk in computer hard disks. Hard disk drives entered common use from the mid-1990s and still account for the majority of computer storage media. If you take a look at a cross-sectional view of a hard disk (refer to illustration), you'll see that it consists of a substrate overlaid with a magnetic layer that records data, a carbon overcoat, and a 1- to 2-nanometer thick layer of surface lubricant. As hard disk capacities have become increasingly larger in recent years, so the gap between the read/write head and the protective film has had to become smaller and smaller to increase memory density. The theme of our research is to make lubricant films as thin as possible so as to better enable the reduction of this head-to-disk gap. When we develop a hard disk lubricant, it goes through the design, prototype, and in-house evaluation stages, and is then evaluated by the customer. If the lubricant performs well in this evaluation, the customer will decide to approve it for use and employ it. What I really enjoy about my job is the way in which we customize each individual product on a project-by-project basis.

Challenges involved in research We only get an evaluation of how the product actually performs on the factory floor when the customer starts using the product

We have almost reached the point where hard disk surface lubricant films are required to be around a single molecule thick. Developing products that fulfill the various functions required of lubricants is not easy in the first place—lubricants cannot be allowed to splatter due to centrifugal force during high speed rotation, they must have the liquidity to allow self-repair in the event the film breaks due to contact with the end of the head, and must also have heat resistance, degradation resistance, coatability, and other characteristics to stabilize the product. After prototyping and in-house evaluation, the hard disk lubricant film that we have developed is evaluated by the customer. It always frustrates me that we're not able to evaluate the lubricant in-house using the same criteria as the customer. We don't know what the results will be until we apply the lubricant to the hard disk at the customer's factory. Synthesizing a surface lubricant can take anywhere from several weeks to several months, but we make improvements until the customer is satisfied and conduct experiments and analysis as we fight against the clock.

Distinctiveness Producing very pure surface lubricants with precision refining technologies

One of MORESCO's strengths is its refining technologies. For example, increasing the purity of a raw material by refining it, makes it easier to draw out the performance of the raw material itself. In a synthetic reaction, it is possible to prevent a reduction in reactivity caused by impurities in the raw material. Creating a finished product with fewer impurities in the refining process after surface lubricant synthesis requires skill. As a leading manufacturer of hard disk surface lubricants, the knowledge we have acquired from our experience in manufacturing numerous highly refined products is one of our strengths.

We are also very good at responding promptly and flexibly to customer requests. You could say that its a strength of any SME, but because we're a small team, it's easy to approach our managers, which lets us decide what action to take next quickly. We're always in close contact with our customers through face-to-face meetings, conference calls, and e-mail and so on, and I think this lets us build relationships of trust by taking proposals from the customer and the team, and immediately bringing them to life.

Problem solving We solved problems related to the appearance of impurities and the deterioration of adhesive properties by completely changing the manufacturing method and adjusting refinement criteria

When developing a product, we solve issues as they arise, but on one occasion we had problems with the purity of a product that had already been commercialized. Impurities that we hadn't been able to detect using our own analysis equipment showed up when the lubricant was applied to hard disks at the customer's factory. We resolved the problem by completely changing the manufacturing method, but when we tried the new lubricant, its adhesive properties had deteriorated despite the fact that we'd prepared it using exactly the same standard as before. Thinking that the change in manufacturing method could be what was affecting the lubricant, we thoroughly reviewed the process, compared the new product against the original one, and analyzed its components. As a result, we realized that we would be able to optimize the content of the components that contribute to adhesive properties by establishing a new standard and changing refining process criteria. In this way, we succeeded in improving the lubricant's adhesive properties to the required level, and the customer decided to employ the product, which we then went on to commercialize. The whole department is involved in the development process, so when we encounter problems like this we are able to suggest ideas and come up with solutions as a team.

Attitude to work Be sensitive to new information and quickly come up with innovative proposals

When it comes to our research and development work, we always try to be as customer focused as possible. We want to be able to meet the customer's needs in terms of delivery period and performance rather than doing things at our convenience. Believing that making quality products is the foundation of trust, we approach development by talking to the customer and bouncing ideas off each other to come up with the optimal solution. In order to do this, we realize that we have to keep producing innovative proposals.

Given the fact that hard disk recording methods are changing, we are very sensitive to any new information so that we can incorporate it in proposals for new lubricants. We aim to keep a firm eye on developments on the rapidly changing hard disk industry, so that we can provide quality products at the right time. To achieve this, we will strive to respond with flexibility without clinging to fixed ideas.

▲to top

vol.1 Synthetic Lubricants Division R&D Department for Synthetic Lubricants Aya Inoue

Overcoming challenges together with the customer to supply the ideal product at the ideal time
Research theme
Challenges involved in research
Problem solving
Attitude to work