IC tag

1. An integrated circuit tag that is attached to an item of merchandise, comprising:

an item information storage unit that stores item information, wherein the item information includes an item price, a first discount information, a discount start time indicating a time to start discounting, and encryption information that indicates whether the item information is to be encrypted;

an item information controller that provides control to change the item information;

an item price calculation processor that corrects the item price based on the first discount information if the discount start time has passed; and

an item information display unit that displays the item information stored, wherein

if the item information controller provides control to change the item information stored based on an instruction wirelessly transmitted from a control device or the item price calculation processor corrects the item price, then the item information display unit displays the item information changed or corrected, and

the item information controller is further configured to encrypt the item information at a time when the item is sold, based on an instruction from the control device if the encryption information indicates that the item information is to be encrypted.

2. The integrated circuit tag according to claim 1 , further comprising:

a discount information updating unit that updates the first discount information.

3. The integrated circuit tag according to claim 1 , wherein the item information further includes a Best Before date of the item, and

the integrated circuit tag further comprises:

an expiration detector that detects whether or not the Best Before date of the item has expired, using a timer, wherein if the expiration detector detects that the Best Before date has expired, the item information display unit displays a message that the Best Before date has expired; and

a display color changing unit that changes a color of an expiration information displayed if the Best Before date has expired, wherein the expiration information includes the Best Before date being displayed or the message.

4. The integrated circuit tag according to claim 1 , wherein the item information includes a Best Before date of the item; and

the integrated circuit tag further comprises:

an expiration determining unit that determines whether the Best Before date of the item has expired, based on a present time acquired periodically from a control device;

the item information display unit displays a message if the expiration determining unit determines that the Best Before date has expired; and

a display color changing unit that changes a color of an expiration information displayed, if the Best Before date has expired, wherein the expiration information includes the Best Before date being displayed or the message.

5. The integrated circuit tag according to claim 1 , wherein the first discount information includes:

a second discount information that indicates a numeral; and

a discount method that indicates a method of discounting using the numeral.

6. The integrated circuit tag according to claim 1 , wherein the item price calculation processor monitors the discount start time and determines if the discount start time has passed.

7. The integrated circuit tag according to claim 1 , wherein the item information further includes a Best Before date of the item; and

the item information display unit displays the Best Before date.

8. The integrated circuit tag according to claim 7 , further comprising a display color changing unit that changes a color of the Best Before date being displayed, if the Best Before date has expired.

9. The integrated circuit tag according to claim 8 , further comprising an expiration detector that detects whether the Best Before date of the item has expired, using a timer or based on a present time acquired periodically from the control device.

10. The integrated circuit tag according to claim 7 , wherein the item information display unit displays a message indicating that the Best Before date has expired, if the Best Before date has expired.

11. The integrated circuit tag according to claim 10 , further comprising a display color changing unit that changes a color of the message, if the Best Before date has expired.

12. The integrated circuit tag according to claim 10 , further comprising an expiration detector that detects whether the Best Before date of the item has expired, using a timer or based on a present time acquired periodically from the control device.

13. The integrated circuit tag according to claim 1 , wherein the first discount information is an amount to be discounted, and the item price calculation processor corrects the item price by subtracting the amount to be discounted from the item price.