"The judge's decision, we're pleased with it," PFT president Jerry Jordan said moments after Padilla issued the order. "We hope it will end here, but we're pretty sure it won't."
District spokesman Fernando Gallard said the SRC would appeal to Commonwealth Court.
"We expect this to be just one of many legal steps we will have to take," he said. "We are now moving on to the next."
The district said in a statement released later that it was disappointed with the results of the hearing.
"The School District expects to ultimately prevail in the courts and will pursue this matter forcefully, for the cause is urgent and the children of Philadelphia cannot continue waiting," the statement said.
"The changes temporarily placed on hold by [Monday's] injunction are estimated to save more than $200 million in the next four years. These are crucial resources for the children of Philadelphia."
The SRC had opposed the injunction on the ground that there was no need to move so swiftly because most of the changes would not begin for two months.
"We don't see the need for urgency," A. Richard Feldman, an attorney for the five-member commission, told the judge.
The terms the SRC voted to impose would require most of the PFT's 11,500 members to contribute from 10 percent to 13 percent of the cost of their medical plans beginning Dec. 15. That works out to $21 to $200 per month, depending on several factors, including salary and type of coverage, according to the district. Most members now pay nothing.
Feldman also told the court that while the hearing had focused on the harm the changes would cause PFT members, the SRC cannot lose sight of the needs of the district's 130,000 students.
"Someone has to stand up and be the adult and say, 'This is what we have to do,' " Feldman said.
The SRC has said that the changes would save the cash-strapped district $44 million this school year and that money would be used on more resources for students. Last week, the district released $15 million to school principals.
Assistant Superintendent Cheryl Logan testified that the 44 schools she oversees decided to use their share of the money to hire counselors, teachers, and other staff, and to order materials and supplies.
District representatives said Monday that the injunction could prevent the district from releasing an additional $15 million in early 2015 and a further $13.8 million in April.
After the judge issued her order, the district said in a statement that it was "evaluating the impact" that the day's court action could have on the district's ability to provide additional resources for students.
Feldman and his law partner Richard L. Bazelon said the SRC reluctantly used its extraordinary powers to cancel the PFT contract and impose the benefit changes because the sides had reached an impasse after 21 months of bargaining.
Both sides said the last collective bargaining session was held July 1.
Jordan told the judge that SRC negotiators never told the union that a list of demands they had given the day before was a "last, final offer." He said the SRC called off a session that had been scheduled for July 2.
"The district canceled that session, and we haven't met since," Jordan said.
The SRC has said it hopes to return to the bargaining table, but PFT lawyer Ralph Teti warned that the SRC's decision to cancel the contract "undermines the very fabric of collective bargaining."
He said it would be difficult for the PFT to reach a new agreement with the SRC knowing that it could be torn up.