"To add fuel to the fire, while the union negotiated the pay rise, non-union members also received it."
Gallagher said it had been in talks with the company since August last year but had failed to resolve matters.
"Our people who missed out want that money and they're determined to fight to get it," he said.
Gallagher said union members were also unhappy about the company's 2 per cent pay offer, with no backpay, despite their collective agreement expiring in July last year.
"This is a multi-national company that has been mismanaged over the past few years and there have been job losses affecting our members,"
"Those who remain are working harder, smarter and longer and they want fair recompense," he said.
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Fuji Xerox New Zealand said it was disappointed about the union's decision to go on strike in the middle of collective agreement negotiations.
Danielle Everett, general manager of human resources and legal, said its latest offer was an increase in based salary of 2 per cent which would start on July 1 and its performance bonuses would increase by up to 60 per cent.
"This represents an approximate 3.1 per cent increase to overall salary, not taking the superannuation impact benefit into consideration."
"In the wider context of the company's financial situation where a number of our workforce have had to be made redundant and more than $370 million of losses written off over the last two years, we are doing everything we reasonably can to recognise the value of our people here."
Everett said it remained hopeful the union would understand its situation and return to the negotiating table.
She said union members made up one-third of its engineering workforce and it had enough staff still working to ensure no impact on its customers.
Everett said it was unclear if the union's current position and was awaiting a full and formal response following substantial correspondence send in December.
She said the company was unable to agree to the union's claim of no pass on as it treated all workers as one team, regardless of whether they were union members or not.
The "inappropriate accounting" took place over a six-year period from March 2011 to March 2016 culminating in Fujifilm booking losses of $473m, including about $355m from the New Zealand company.
The root of the cause, according to an independent report released in 2017, was a "sales first at any cost culture" to meet sales targets, and commissions that saw photocopier sales staff making more money than Cabinet ministers.
Lavish bonuses were handed out while holidays to senior executives and their wives were later costed at up to $25,000 a head.
Following media attention by the National Business Review, majority shareholder Fujifilm commissioned an independent report and in June 2017 the findings were translated into English and released publicly.
The report found Fuji Xerox NZ consistently exaggerated sales revenue, including through double recording of sales, recording fictitious sales and fictitious recording of expenses.
Fuji Xerox, which has been under investigation by the Serious Fraud Office since October 2017, suspended itself from taking on new contracts with government organisations.
MBIE, which administers the All of Government procurement process, has not disclosed the criteria which will be applied to lift the suspension.
