Development of Analytical Instruments for Industry - ACS Publications

Seiko Instruments, Inc. 31-1, Kameido 6-chome, Koto-ku. Tokyo 136, Japan. Most analytical instruments are origi- nally developed for research purposes...
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Development of Analytical Instruments for Industry Reinosuke Hara Seiko Instruments, Inc. 31-1, Kameido 6-chome, Koto-ku Tokyo 136, Japan

Most analytical instruments are origi­ nally developed for research purposes. Some of these instruments are subse­ quently developed into commercial products, whereas others are eventual­ ly forgotten. Whether a particular sci­ entific instrument can maintain a long life as a commercial product depends on two main factors: reliability and routine applications for the instrument in both research and industrial labora­ tories. As with other new products, the so-called S-curve phenomenon (1) is observed in scientific instrument de­ velopment. For the first few years,

and by Wendt and Fassel (3). The rocky road leading to the acceptance of ICP-AES as a viable method for mul-

tielement determinations was de­ scribed in this J O U R N A L in 1979 by

Velmer Fassel (4 and references cited

Multichannel Sequential

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REPORT newly developed scientific instruments are not widely accepted. (For example, it takes at least three to five years for a newly developed instrument to become accepted as a quality control tool in industry.) The market expands as ap­ plications are explored, and many com­ mercial instruments are introduced. Eventually, a saturation level is reached. Exploration of applications This REPORT describes the process by which instruments that are developed for research applications are success­ fully commercialized. Inductively cou­ pled plasma-atomic emission spectros­ copy (ICP-AES) and X-ray fluores­ cence (XRF) are highlighted. In the mid-1960s, the inductively coupled plasma (ICP) was introduced independently by Greenfield et al. (2)



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Figure 1. Number of (a) ICP spectrometers and (b) XRF spectrometers in operation in Japan.

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therein). That REPORT was based on his award address (ACS Award in Analytical Chemistry) and offered Fassel's commentary on this "new analytical approach" (see box). Several prototype ICP-AES instruments were developed for research purposes (5), but it was another 10 years before this technique became an accepted tool for routine analysis in industry. The first commercial ICP-AES instrument was introduced in 1974 (6), and three years later the first ICP was imported into Japan. In 1978 Japanese manufacturers started to produce commercial ICP instruments as applications expanded. To meet the need for an instrument that could analyze new materials (and determine, for example, individual rare-earth elements), instrument manufacturers introduced a sequential, computer-controlled ICP in 1982. Eventually, the number of ICPs used in industry increased sharply (7), and beginning in 1985, sales mushroomed (Figure la). Since the introduction of this instrument, manufacturers have continued applications research and development to upgrade and improve the precision of the ICP. Today more than 1200 ICPs are used in Japan alone. XRF spectrometers were also developed primarily for research purposes (8). Interest in XRF instruments escalated when one such instrument was used to measure the thickness of zinc and tin coatings on steel (9), and more recently, to measure the coating thickness of silver, gold, and other precious metals in the electronics industry (10). As new applications were explored, the number of XRF instruments increased sharply (Figure lb). Exploration of new applications is thus the key to expanding the market for any analytical instrument, and analytical utility of a particular instru-

ment can best be exploited when no alternative analytical method is available. For example, thermal analysis can be used for quality control of dairy products such as chocolate. A freshly prepared product can be distinguished from a one-year-old product and from a product showing obvious changes by the thermal analysis pattern (11). The

lack of alternative methods for this type of analysis makes thermal analysis attractive to the dairy industry. The development cycle

Just as potential applications often bring about advances in instrument design, advances in design often bring about new useful applications. Im-

Slmultaneous or Sequential Determination of the Elements at All Concentration Levels—The Renaissance of an Old Approach (Excerpted from Fassel, V. A. Anal. Chem. 1979, 51, 1290 A-1308 A) The surprising lack of interest in the ICP-AES approach to elemental determinations is reminiscent of Sir Allen Walsh's experience (Anal. Chem. 1974, 46, 698) following the publication of the pioneering papers in flame atomic absorption spectroscopy (AAS). His experience and ours are, I believe, excellent examples of how tacit acceptance of methodologies as they are, and perhaps a liberal sprinkling of mental paralysis, can influence the timely acceptance of new ideas. Because ICP-AES was originally conceived as an alternative approach for the determination of minor and trace constituents, it had to vie for attention at a time when AAS was experiencing its phenomenal growth and wide acceptance. The fact that AAS provided a relatively simple, highly specific way for elemental determination at the minor or trace concentration level contributed so much to its popularity that the use of alternative techniques for performing the same tasks suffered precipitous declines. The technique that experienced the greatest decline in usage was atomic emission spectroscopy, which during the period from the mid-1930's to the early 1960's was often, if not usually, the method of choice for multielement determinations at the minor or trace concentration level. Although spark-arc excitation AES retained its important role for compositional control in the metals industries, there is no doubt that its use as a general analytical tool experienced a sharp decline from the mid-1960's to the early 1970's, whereas AAS was ascending its steep popularity curve. The interest of analytical chemists or spectroscopists in AES was further undermined when some AAS enthusiasts directed intellectual darts at the principle of observing free atoms in emission rather than in absorption. These darts consisted of undocumented, and usually theoretically unsound, claims regarding the alleged superiority of observing free atoms in absorption rather than in emission. Thus, the claim that AAS should exhibit far superior powers of detection because the bulk of the free atoms in atomization cells were in the ground state in contrast to the far smaller number density in excited states, did not rest on sound theoretical bases. Neither did the claim that because the fraction of atoms in excited states was very small, the observation of free atoms in emission was subject to serious "excitation interferences" arising from collisional deactivation, preferential excitation, or energy transfer processes in general. Other assertions suggested that, in spite of recorded successes in the past, spectral line interferences were so inseparable, and temperature changes in the excitation cells so uncontrollable, that the observation of free atoms in emission for analytical purposes was surely destined for failure. These assertions were often read in amused astonishment by myself and others.

ANALYTICAL CHEMISTRY, VOL. 62, NO. 24, DECEMBER 15, 1990 · 1241 A

REPORT duce on a commercial basis. Alternatively, the design may be too sophisticated and thus difficult to maintain.

Industry

Reliability Marketing

Maintenance/service

Applications

R&D design

University or research institution

Sales Commercial instruments Production

Quality control

Although analytical instruments are based on highly sophisticated technology and design, failure can occur. Production is characterized by a variety of instruments that are produced in small lots rather than by mass production. (For example, most scientific instruments are produced in lots of less than 50, whereas mass-produced products such as watches are produced in lots of several hundred to a million.) The sophistication of scientific instruments requires a quality control system different from that developed for massproduced products. Certain factors, such as undesirable environmental conditions (e.g., high humidity or temperature or dust), careless handling, unsatisfactory assembly, and poor design, can cause fail-

Figure 2. The development cycle.

provements in sensitivity, resolution, stability, and dependability, along with simplified operation, often spur new applications, whereas new applications often require additional improvement in the performance of an instrument. The development of analytical instruments on a commercial basis involves several steps, including marketing, R&D, prototype design, commercial instrument design, production, sales, and maintenance/service (Figure 2). To understand existing and potential market needs, cooperation with industrial laboratories is necessary, whereas cooperation with universities or research institutions is helpful in R&D and prototype design. For example, Seiko Instruments and the Japanese electronic parts industry cooperated in the design and construction of a customized X-ray fluorescence instrument to measure the thickness of gold plating on electronic connectors. Only a limited number of these instruments were built, but because of their usefulness, the prototype was later improved and standardized, leading to the development of versatile models for a variety of applications. The transformation of a prototype instrument into a commercial instrument is the most crucial step in the entire design process and the one with the highest risk of failure. Many prototypes do not satisfy QCD (quality, cost, delivery) requirements. For example, although the prototype may be of high quality and exhibit excellent performance, it may be too expensive to pro-

Customer

Complaints Information relating to failure or unsatisfactory performance

Analysis of failure to clarify cause

Discussions with relevant groups: design, R&D, and production

Action

Redesign if needed

Figure 3. Failure correction system.

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Maintenance/ service group

Quality control group

ure or unsatisfactory performance of newly developed scientific instru­ ments. It is impossible to predict all conditions in which an analytical in­ strument will be used before the instru­ ment goes into operation, and such un­ predictable conditions can also cause failure or unsatisfactory performance in the initial stages of operation. The failure rate of newly developed instru­ ments is usually higher than that of mass-produced durable consumer products. When failure or unsatisfactory per­ formance does occur, the manufacturer must take immediate action to correct the situation. Quick action is impor­ tant, especially when scientific instru­ ments are used for routine analysis. Adequate repair work by the mainte­ nance/service group does not necessar­ ily lead to a permanent solution be­ cause the problem often relates to the original design or to careless work dur­ ing assembly. Close cooperation among all groups engaged in the development of new in­ struments is thus essential in solving problems of failure and unsatisfactory performance. As shown in Figure 3, such cooperative action should be tak­ en by collecting all relevant informa­ tion, analyzing the problem, and estab­ lishing quality control measures. Al­ though repair work is performed by the maintenance/service group, participa­ tion by the R&D and prototype design groups, along with the quality control group, is needed to analyze the prob­ lem and establish adequate measures for better quality control. Because many failures originate with the basic design of the instrument,

problems relating to quality should never be settled within the sales or maintenance/service groups only, but should include the R&D and design groups. For example, as shown in Fig­ ure 4, most failures in the first-genera­ tion X R F thickness-measuring instru­ ments were related to the original de­ sign—specifically the CPU board, X-ray power supply board, X-ray tube, and X-ray detector. After these prob­ lems were corrected through the joint efforts of the maintenance/service, quality control, and design groups, the number of failures in the second-gener­ ation instruments was drastically re­ duced. Future directions

High-technology industries require so­ phisticated quality control methods that provide precise information on the properties of complex new materials, including highly accurate and sensitive quantitative determination of ele­ ments and isotopes, structure charac­ terization, and surface analysis. Analy­ sis by one analytical method does not necessarily give conclusive informa­ tion, and disagreement is often ob­ served in the results obtained with dif­ ferent techniques. Scientists must thus develop new or improved instrumenta­ tion that will provide the ability to per­ form parallel analysis using different analytical methods. High-technology industries will also require instruments that can operate in ultraclean laborato­ ries and in a high vacuum. Analytical instruments are also be­ ing more widely used in process analy­ sis in factories; data obtained with

these instruments are being incorpo­ rated into computer-integrated manu­ facturing systems. Future develop­ ments in scientific instruments will probably be directed toward further automation of these process analysis systems.

The author would like to acknowledge the assist­ ance of Hiroshi Ishijima, Kazuo Ohashi, Junko Sugiyama, Robert Johnson, and Mike Oswald in the preparation of this REPORT. References

(1) Zander, A. T. Anal. Chem. 1990, 62, 307A-314A. (2) Greenfield, S.; Jones, I. L.; Berry, C. T. Analyst 1964,89,713. (3) Wendt, R. H.; Fassel, V. A. Anal. Chem. 1965,37, 720. (4) Fassel, V. A. Anal. Chem. 1979, 51, 1290 A-1308 A. (5) Houk, R. S.; Thompson, J. J. Mass Spec. Rev. 1988, 7,425. (6) Montaser, Α.; Golightly, D. Inductively Coupled Plasmas in Analytical Atomic Spectrometry; VCH Publishers: New York, 1987. (7) 29th Training Course on Instrumental Analysis; The Japan Society for Analyti­ cal Chemistry; Tsukuba City, Ibaragi Pre­ fecture, Japan; June 16-17, 1988. (8) Advances in X-ray Diffractometry and X-ray Spectrography; Parrish, W., Ed; Centrex Publishing Co.; Eindhoven, The Netherlands, 1962. (9) Ishijima, H.; Hara, R.; Sasaki, T. Pro­ ceedings of the International Conference on Industrial Application of Radioiso­ topes and Radiation Technology; Inter­ national Atomic Energy Agency; Septem­ ber 1981. (10) Satoh, M. J. Surface Finishing Soc. Jap. 1989,40, 220-25. (11) Ishizuka, R. Nishizawa, K. Proceed­ ings of the 3rd Training Course on Ther­ mal Analysis; The Society of Calorimetry and Thermal Analysis: Tokyo, May 1978.

CPU board X-ray power supply board X-ray tube X-ray detector Fuses Key switch X-ray shutter Printer

Figure 4. Number of failures of components in the XRF thickness-measuring instru­ ment between April 1983 and March 1984.

Reinosuke Hara, president and chief executive officer of Seiko Instruments, Inc., received a B.S. degree (1945) and a Ph.D. (1952) from the University of Tokyo. Before joining Seiko in 1969, he was a postdoctoral research asso­ ciate at the University of Washington, Harvard University, and Louisiana State University, as well as a research chemist at the Japan Atomic Energy Research Institute and the Interna­ tional Atomic Energy Agency.

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