Union workers at a ExxonMobil research facility in Clinton Township are planning to strike starting Thursday.

Members of The Independent Laboratory Employees Union have been working without a contract since the end of May last year, according to a statement on the union’s website.

Some 200 union members are planning to strike Thursday and Friday to protest what they called “bad faith bargaining” practices, according to the statement. About 1,200 people work at ExxonMobil’s Research and Engineering Technology Center.

Union members are expected to picket both days at the center’s two entrances, one off Route 22 and the other off Route 33, according to union President Michael Myers. There have been 25 bargaining sessions between the union and ExxonMobil, according to the statement.

“The ILEU-represented employees are currently working under the existing terms and conditions of the previous contract," Sarah Nordin a spokesperson for ExxonMobil, said. "(ExxonMobil) has had a long and successful relationship with the ILEU, and we look forward to working with the union on a resolution.”

According to the union, among the issues is that ExxonMobil is offering its members a new contract with yearly wage increases below the average 3% increase given to other union workers, and with no retroactive increase for the year they have been without a contract. Workers would get a $2,500 bonus if the contract is ratified.

The union has been unable to get an agreement with the company on personal time, and union workers get one week of parental paid time off each year, in contrast to eight weeks offered to all non-unionized employees, according to the union statement.

Olivia Rizzo may be reached at orizzo@njadvancemedia.com. Follow her on Twitter @LivRizz. Find NJ.com on Facebook. Have a tip? Tell us.nj.com/tips.

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