Now I understand what you mean. Yes, hatcheries often use RIR/NH over barred Rocks to create black sex links. Because that cross tends to create the best hybrid egg layer. However that isn't the only way to create black sex links.
Black sex links can be created by crossing just about any non-barred, non-white male with a barred/cuckoo (does not have to be a pure breed, just has to be barred/cuckoo) female. The hen will pass the barring gene on to only her male offspring, since it's on the Z chromosome (roosters are ZZ, hens ZW - hens also determine a chick's sex). Cockerels will have the white head spot indicating the barring gene is present while the pullet chicks will not.