>>22
これじゃだめなのか？

type
   TForm1 = class(TForm)
      ApplicationEvents1: TApplicationEvents;
      procedure ApplicationEvents1Minimize(Sender: TObject);
   private
      { Private 宣言 }
   public
      { Public 宣言 }
   end;

var
   Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.ApplicationEvents1Minimize(Sender: TObject);
begin
   Hide;
end;

end.