Home >>  Marking Cards Invisible Ink  >>  Properties of invisible ink

Properties of invisible ink

What an "ideal" invisible ink is depends on its intended use. For example, property marking should ideally be done with ink easily read under ultraviolet light, whereas in espionage such an ink would be considered too easily detectable since a large number of letters may be screened relatively quickly using UV light.

Invisible inks are inherently "insecure" against a determined and well-equipped inspector, which must be balanced against the logistical difficulty in carrying out mass-screening of posted mail. It is easier to perform large-scale undetected screening of millions of electronic communications, than to mass-screen even a small fraction of conventional mail. Apart from in dictatorships where large numbers of personnel are employed to spy on fellow nationals, screening of posted mail is only feasible in particular situations, such as letters to and from a particular suspect or facility.

The World War II SOE training manual identified the following properties of an "ideal" invisible ink:

Mixes with water.

Non-volatile, i.e. no pronounced smell.

Not depositing crystals on paper, i.e. not easily seen in glancing light.

Invisible under ultraviolet light.

Does not decompose or discolor the paper e.g. silver nitrate.

Nonreactive with iodine, or with any of the other usual developers.

Potential developers for the ink should be as few as possible.

Should not develop under heat.

Easily obtainable and has at least one plausible innocent use by the holder.

Not a compound of several chemicals, as this would violate #7.

From practical experience "6" and "9" were usually incompatible. SOE agents were trained not to risk their lives through reliance on insecure inks, most of which were from World War I. In general, SOE used invisible inks as a back-up method of communication when other, more secure communication techniques were unavailable. The agency was known to supply special inks to its field agents, rather than have them depend upon improvisation from obtainable everyday chemicals. When agents were forced to improvise, they were advised to dilute their invisible ink as much as possible to reduce chances of detection.

so let me use ideal invisible ink to make poker cards, you can make good luminous marked cards.

MESSAGE
*Name: E-mail:
*Phone / Whatsapp: Skype:
*Message:
Code: Refresh
LEAVE A MESSAGE
Name: Adam IP: 148.75.180.139 Time: 2018-06-03 13:11:41
Content: Hello , I am looking for a pair of  Tapper mercury dice. I collect dice amd would like a set for my collection. there currently seems to be no such dice on the market currently , but I do know they exist. Can you / do you create such dice ? I am looking forward to your response.
Admin_reply: Thanks for your inquiry about mercury dices, I have sent you email, please check and reply, thanks
Name: Mark Charles IP: 207.161.51.20 Time: 2018-05-19 05:49:57
Content: Hi, I am looking for 3 pair of glasses and a pen/marker/ink that can be used to mark playing cards for an escape room puzzle. Glasses must be durable as they will be handled by hundreds of people. Shipping to Winnipeg, Canada
Admin_reply: Thanks for your inquiry about glasses, a pen/marker/ink for marking playing cards, I have sent you email, please check and reply, thanks
Name: Prakash IP: 192.119.160.242 Time: 2018-02-07 23:40:04
Content: I want uv contact lens but I want to know that how it works?
Admin_reply: Thanks for your inquiry about UV contact lenses, I have sent you email, please check and reply, thanks

First | Previous | | Last

×

E-mail: marked-cards2012@hotmail.com

Skype: marked-cards2012

WhatsApp / Wechat: +86 188 2517 5787