[tima]

If warm-up doesn't help, I'd contact Zaino...

From the Zaino Web site:

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Q: What is the usable shelf life of Zaino products?

A: A 70° room temperature is best for the longevity of Zaino products. Due to the optical additives used, extreme heat or cold can result in a decrease in gloss-enhancing properties.

When stored at average room temperature between 65° and 75° degrees, shelf life is as follows:
Z-PC 3+ years
Z-1 For optimum results, use before 3 years.
Z-2 For optimum results, use before 3 years.
Z-3 For optimum results, use before 3 years.
Z-5 For optimum results, use before 3 years.
Z-6 5+ years
Z-7 5+ years
Z-8 5+ years
Z-9 5+ years
Z-10 For optimum results, use before 2 years.
Z-12 For optimum results, use before 2 years.
Z-14 For optimum results, use before 2 years.
Z-16 3 to 5 years
Z-18 5 years +
ZFX For optimum results, keep tightly capped, avoiding moisture. Use before 18 months.
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