What does "latent imprint" mean with this note? [solved]

This is mine:

Has obvious UV activity, the blue fibres and the “10 KPБ" on the left.

Is this what the entry “latent imprint” is referring to?

My note has nothing latent when viewed under white light.

Banknote Museum

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Thanks I'll make a modification request.

I have the following information.

Counterfeiting of reusable coupons, which had primitive protection in the form of a parquet watermark, became widespread soon after they were put into circulation. In view of this, the government has taken appropriate measures to improve the protection of coupons from counterfeiting. New batches of reusable coupons were printed in denominations of 1, 3, 5, 10, 25, 50, and 100 karbovanets with improved protection in the form of the addition of elements visible in ultraviolet rays.

One of these security elements was a vertical digital image of the coupon denomination and the letters КРБ, visible under ultraviolet light, on the edge of the banknote on the left side of the image of Lybid. Particles of threads visible in ultraviolet were also added to the banknote paper on which the coupons were printed. Also visible in ultraviolet rays was a rectangle with yellow wavy rays in the center of the obverse of the banknote and a large number of the coupon denomination.

It should be noted that the 1991 reusable coupons with improved UV protection are not consistent and there are variations.

Thanks, I might look for more of these later!