Article: Although most hardware clones were not produced under license by Nintendo, certain companies were granted licenses to produce NES-compatible devices. The Sharp Corporation produced at least two such clones: the Twin Famicom and the SHARP 19SC111 television. The Twin Famicom was compatible with both Famicom cartridges and Famicom Disk System disks. It was available in two colors (red and black) and used hardwired controllers (as did the original Famicom), but it featured a different case design. The SHARP 19SC111 television was a television which included a built-in Famicom. A similar licensing deal was reached with Hyundai Electronics, who licensed the system under the name Comboy in the South Korean market. This deal with Hyundai was made necessary because of the South Korean government's wide ban on all Japanese "cultural products", which remained in effect until 1998 and ensured that the only way Japanese products could legally enter the South Korean market was through licensing to a third-party (non-Japanese) distributor (see also Japan–Korea disputes).

Now answer this question: Until how long did South Korea ban Japanese cultural products?
1998