Eastman Kodak manufactured their own backing paper until the steep decline of film sales. They used old techniques, old machinery, old inks.
When that decline happened they stopped making backing paper, and were left with several years of supply.
So they got rid of their production capacity.
In the meantime, the paper manufacturing and printing industry went through sea changes in technology and availability.
When Eastman Kodak finally ran out of backing paper that they had manufactured, they sought new stuff from the available manufacturers and printers.
And it turned out that the availability was really poor, and the single source that was able to supply something which met their expected requirements, ended up supplying product that met those requirements, but turned out to fail over time, on an unpredictable and never fully understood way.
But sometimes, unexpected things happen to components like backing paper, which always has been the source of a small amount of problems, and the incidence of those problems increases.