"They kept making threats and saying they were going to take her away to work in a massage parlour," he remembers. "It was just after the time when that company president was found in the mountains, murdered by the Yakuza [crime gangs]. I was afraid that I would go the same way or that they would get to my wife. On the day that the money was due, we did a yonige."
The word means "night disappearance", and in Mr Shiozaki's case it was rather simple. "We hired a car, and at midnight my wife, three children, mother-in-law and me just drove out of town.
"All we could think about was dying. We were driving along the expressway and my wife kept saying, `Suppose I turn the wheel right into the traffic instead of left?'"
But the Shiozakis reached Tokyo safely where they entered the statistics, not as suicides or traffic casualties, but among the growing ranks of the vanished.
No one knows exactly how many Japanese choose to disappear, but the indications are that their numbers are growing. The Tokyo Yellow Pages contains dozens of advertisements for removals companies offering euphemistic services such as "emergency moving" and "night-time removals".
This week sees the first episode of a new television drama, based on a series of successful films, about the adventures of a firm of yonigeya - "night vanishers", who help people in distress to escape without trace.
Most of the real-life vanishers are reluctant to talk, but one small firm reports that one in 20 of its moves are of people who want to disappear.
In the old days, customers were often women, fleeing violent husbands or lovers, or even eloping couples. These days, as in the case of Mr Shiozaki's escape from bankruptcy and debts, the reasons for yonige are increasingly economic.
"This kind of thing has always gone on, but it became much more common when the bubble economy came to an end about four or five years ago," said the manager of Ai-Ai Deliveries in Tokyo.
These days, the typical yonige clients are families. "We take cash in advance," says another remover. "If anyone comes asking what happened to them, we tell them they switched to another car before they got to their destination."
According to police statistics, there was a 17 per cent rise in the number of professionals and managers reported missing last year. At the root of this alarming increase is Japan's recession: this week the government's survey of business morale showed that small and medium-sized manufacturers are more pessimistic than at any time since the polls began 31 years ago. On top of this, Japan is a difficult country in which to suffer failure - not because of a lack of appropriate legislation, but because of social attitudes to debt and bankruptcy.
"This is a country in which bankruptcy is regarded by many people as a crime," says Seiichi Noguchi, who runs a voluntary group for small businessmen in financial trouble. "Nine out of 10 people have no idea about the legal measures which can be taken when a business is failing, and they don't understand that bankruptcy laws exist to help restructure a business."
Ten per cent of the people who consult Mr Noguchi have previously "vanished". Half of them are single men, but half - like the Shiozakis - are families.
"People who disappear have a much harder time than those who stay and face up to their problems," says Mr Noguchi, and the experience of the Shiozakis bears this out.
After disappearing from their home in the city of Nagoya in 1980, they began a new life in Tokyo, living in two small rooms. It was too dangerous to change their local residents' registration, which would have alerted their creditors - but without it, it was difficult to find a school for the children. "For three years, we were always on edge and afraid that the Yakuza would track us down," Mr Shiozaki remembers. "Whenever I went out I wore dark glasses."
Eventually, with much trepidation, he decided to return to Nagoya, to apologise to his business partners and creditors - although as a precaution he waited until after most of his financial liabilities had expired.
"I thought that they would spit on me and call me a fool, but the first thing they said was `How are you, Shiozaki-san?' They helped me set up a new business, and I'm doing pretty well now. I realised that if you run away from something once, then you will be running away for the rest of your life."Reuse content