$arrProductの配列が、このように表示されました。
やはり、７枚目以降の画像が取得できていない状況です。
エラーログは出ておりません。
原因はなんでしょうか？
何度も質問にお応えくださいまして、ありがとうございます。

-----------------------
Array (63)
product_id => "6"
name => "トップス"
maker_id => null
status => "1"
comment1 => null
comment2 => null
comment3 => "トップス,"
comment4 => null
comment5 => null
comment6 => null
note => null
main_list_comment => "トップス"
main_list_image => "08042125_53df7bce358ab.jpg"
main_comment => "<table> <tr> <td>Point1:</td> ..."
main_image => "noimage_main.png"
main_large_image => null
sub_title1 => null
sub_comment1 => null
sub_image1 => null
sub_large_image1 => null
sub_title2 => null
sub_comment2 => null
sub_image2 => "08042127_53df7c4e15e91.jpg"
sub_large_image2 => null
sub_title3 => null
sub_comment3 => null
sub_image3 => "08051559_53e080df42a0a.jpg"
sub_large_image3 => null
sub_title4 => null
sub_comment4 => null
sub_image4 => "08042128_53df7c7271c67.jpg"
sub_large_image4 => null
sub_title5 => null
sub_comment5 => "<table > <tr> <td>肩幅</td> ..."
sub_image5 => "08081625_53e47b847d8e9.gif"
sub_large_image5 => "08081654_53e48223ddef5.gif"
sub_title6 => null
sub_comment6 => null
sub_image6 => "08181805_53f1c1d3ad662.jpg"
sub_large_image6 => "08191659_53f303ee987d9.jpg"
del_flg => "0"
creator_id => "2"
create_date => "2014-08-04 21:29:04"
update_date => "2014-08-19 17:00:04"
deliv_date_id => null
product_code_min => "T-0001"
product_code_max => "T-0001"
price01_min => "250"
price01_max => "250"
price02_min => "250"
price02_max => "250"
stock_min => "1"
stock_max => "1"
stock_unlimited_min => "0"
stock_unlimited_max => "0"
point_rate => "0"
deliv_fee => null
class_count => "1"
maker_name => null
price01_min_inctax => 270
price01_max_inctax => 270
price02_min_inctax => 270
price02_max_inctax => 270 productsub_max;9
------------------------------------------