First of all, you need to check who drafted the contract. If it is a printing house, then the special clauses in the contract may be invalid for you.
Secondly, according to what you said, although the date agreed in the contract has passed, there is still a printing quality problem. This kind of problem cannot exist just because the two parties have agreed on a time limit. After the expiration of the printing quality, The quality is completely irresponsible.
To sum up, you can rest assured that the printing company will not be legally responsible if it wants to be irresponsible. If the negotiation fails, you can file a lawsuit in court and demand the return of the contract payment and bear the losses for breach of contract.
Don’t worry about the "three-day agreement"
Additional: The official seal of the contract can prove that it is binding on both parties, but I still stick to my point of view, The purpose of making a contract is to have a constraint on printing quality. If there is really a quality defect, then the time when the product defect is discovered is not within the agreed period is not the main problem, but the quality itself. This is the most critical thing, not to mention What the law examines is the facts, and the procedural requirements in civil matters are not very strict.
What you have to look at now is whether there is any ambiguity in the quality agreed in the contract. If there is an error caused by the ambiguity, it is another matter.
Another addition: This is caused by not seeing it when you signed the contract. Let me give you an example and see if it is like this. If so, then your unit is at fault.
For example: Both parties signed a contract and agreed to print. After the agreement, your company sent the original version to the printing factory on the first day and requested printing. However, the next day, your company sent another version to the printing factory. , requiring the printing house to print according to the second edition layout. As a result, the printing house had already completed all the printing on the first day. At this time, you claim that the printing house breached the contract. In this case, you should bear the loss because the printing house has kept its promise.
The key now is whether you requested the printing house not to print the first edition, or told the printing house to stop printing. If there is neither an agreement nor a verbal notification, then you should Bear responsibility for losses.