98 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS • ADHESIVE TAPE ADHESIVE AGENT COTTON PAD oR FILTER PAPER i I Figure 1. Adhesive tape and cotton pad type patch test unit. with components of the adhesive agent on the adhesive tape. Also, the adhesive tape is brought into direct contact with a part of the skin proximate to the cotton pad or the piece of porous sheet. Both of these factors may influence the outcome of the test. AL-TEST © This test was developed in Sweden and adopted by the patch test unit of International Contact Dermatitis Research Group (9). Al-test consists of an aluminum foil covered with polyethylene onto which a filter paper disc is welled without using glue (Figure 2). The filter paper disc to which the test sample is applied is surrounded by an area of polyethylene-coated aluminum foil. This separates the test site from the area to which the adhesive tape is applied to the skin. With this type of patch test unit, the perspiration generated on the skin may flow into and back out of the filter paper disc along the liquid-non-permeable polyethylene sheet and the test sample may dissolve in the perspiration. Also, the perspiration held between the skin and the polyethylene sheet sometimes causes an influence on the skin (10). Some of test samples may ADHESIVE TAPE ADHESIVE AGENT ALUMINUM FOIL POLYETHYLENE SHEET FILTER PAPER DISC I. t Figure 2. Al-test patch test unit.

PATCH TEST UNIT 99 dissolve the polyethylene sheet of the Al-test and the additive of the polyethylene sheet may exude to the surface of the sheet and cause an influence on the skin (11). The migration of test material in perspiration, the additive of the polyethylene sheet and the shortcomings of occlusive patch testing could influence test results. FINN CHAMBER In order to eliminate the contamination of the test sample by the perspiration and the adhesive agent, the Finn Chamber, a tray was developed (12). This tray is made of aluminum and is adhered to the skin by adhesive tape. The test sample is contained in the tray (Figure 3). When this is affixed to the skin, the inside space of the tray I ADHESIVE TAPE ADHESIVE AGENT ALUMINUM TRAY FILTER PAPER DISC ! ! Figure 3. Finn Chamber patch test unit. containing the test sample is sealed by bringing the top end of the peripheral side wall of the tray into contact with the skin. The contamination of the test sample in the inside space of the tray by the adhesive tape and perspiration generated on the skin can therefore be reduced significantly. Other advantages of the chamber test have been described elsewhere (12). Again, however, the adhesive tape is very close to the part of the skin covered with the tray. If both the adhesive tape and the test sample contained in the tray have an influence on the skin, it may be very difficult to distinguish the two influences from each other. It may cause an influence to the skin if the aluminum chamber contains nickel, chromium or cobalt. This is, therefore, an occlusive patch device which has limitations. In addition, the filter paper disc sometimes drops out from the tray when it is used for liquid test samples. KI-CHAMBER We have developed the KI-Chamber in order to test the influence of a test sample on the skin while preventing the contamination of the test sample with perspiration or the adhesive agent. The device consists of an aluminum tray having a bottom whose center portion protrudes toward the inside space of the tray as indicated in Figure 4.