Lee's painting was much inspired by the abstract paintings by Saito Yoshishige (1904-2001), a predecessor of Mono-ha. Lee began working on two series: From Point and From Line. These two series had lasted for 12 years (1972-1984). Lee had made the Push-Up and Cut-Up series in the 1960s, but, compared to the latter series, they had yet to present a clear personal style. Lee aimed at expressing the intrinsic order and change of nature through the regular arrangement of lines and dots and tonal variation.
Lee continued to produce new series: From Winds (1982-86), With Winds (1987-91), Correspondence (1991-2006) and Dialogue (2006). In these series Lee tried to express different ontological natures. In the From Winds and With Winds Series, he adopted vigorously wielded brushstrokes to express movement and energy. In the Correspondence and Dialogue Series, however, he used simple large squares to indicate the calm and silent nature of existence.
At the first glance, Lee U-fan's abstract format reminds one of certain Western abstract paintings. His From Line (Lot 496) of 1978, for instance, bears some resemblance to Hans Hartung's works exclusively rendered in lines. Even so, when viewing Lee and Hartung's paintings side by side, one would notice the greatest difference: one is so careful and regular and the other, so untrammeled in rendering the lines. Upon closer observation, the matured works from the From Point and From Line Series pay special attention to the varying shades of color, from dark to light, from heavy to light, and gradually disappearing into ethereal apparition. This kind of pictorial appearance almost becomes a norm.
The series of From Line and Untitled (Lot 497) mostly used azurite. The Joseon Dynasty (1392-1910), influenced by the blue and white porcelain of Ming-Dynasty China, also used cobalt blue to decorate porcelain. But since Korean did not fully master the application of cobalt, their cobalt blue is not even, and is not as saturated as that of the Ming porcelain. Lee U-fan's blue pigment on the white ground is not even and not saturated, which reflect the traditional Korean blue and white wares. Lee U-fan's use of color indeed reflects deeply-rooted traditional culture.
In terms of painting technique, in the series of From Point and From Wind, Lee uses commercially available canvas treated with oil-based gesso, and applies a very thin layer of yellowish oil paint on the stretched canvas, to be completed with blue or vermillion brushstrokes. Lee's brushwork appears to be done at one stroke, not unlike all the brushstrokes. Yet close examination reveals that his brushstrokes are first rendered by a kind of transparent medium, which may be some sort of commercial varnish, comprising alkyd resin mixed with acrylic. Before this layer of varnish-medium becomes dry pigments are sprinkled onto it. The granular mineral pigments are coarsely ground. The canvas hitherto is placed horizontally, and when it is flipped into vertical position, the excessive pigment granules fall off from the unsized areas. The thickness of accumulated granular pigments decides the shades within each stroke; pigments in the darkest areas may be as thick as 4 millimeters, but practically no pigment particles in the lightest areas.
This technique is derived from traditional glue painting but Lee replaces the glue made from animal hide with synthetic medium. Moreover, he does not use the traditional method of picking up the paint with a brush and render a stroke with varying shades of a color. He, instead, controls the density of pigment granules to alter the shades of a color, which is unique.
This technique, however, is more suitable for straight lines and dots that are more regularly arranged. In his later work East Wind (Lot 495) he uses the brush to pick up the pigments mixed with the synthetic medium, which is more congenial to the irregular forms rendered by curvilinear strokes. This kind of method is more direct, and the forms of stroke and shades of color can be varied more easily, generating a more spontaneous and enliven feeling, resembling the cursive script in traditional calligraphy.
As the main theorist of the Mono-ha Movement, Lee U-fan proposes to maintain as closely as possible the originality of material, and his unique painting technique reflects this kind of theory. One of the reasons for him to grind the azurite into coarse granules and sprinkles them to form shades of color is to emphasize the originality of material. Moreover, the gradual transition from being thick and heavy to being sparse and light, from being substantial to being bare, brings forth the ontological significance of lines or blotches within the pictorial surface. Lee's abstract paintings not only convey theoretical idea but also cultivate new technique, and one supplements the other.