A resist film comprises a dimensionally stable base (B), which is transparent to actinic light in the wavelength range from 300 to 420 nm, and a mask-forming layer (ML) which is sensitive to heat radiation and contains a thermochromic system which, when irradiated with an IR laser having a wavelength greater than 1.00 μm, undergoes an irreversible change in its absorption spectrum in the wavelength range from 300 to 420 nm so that the optical density of the mask-forming layer (ML) in this wavelength range changes by not less than 1.3 units. The base of the resist film can also be applied onto the photosensitive relief-forming layer (RL) of a recording material to give a multilayer image-recording material. Imagewise irradiation with heat, for example using an IR laser, produces, in the mask-forming layer (ML) of the resist film, a UV photomask which is very useful for exposing photosensitive recording materials.

Image-recording materials and image-recording carried out using these

A masking element is prepared with a photosensitive layer on a suitable support, overcoated with a masking layer containing an infrared absorbing compound and a thermally bleachable dye. The dye is bleached by imagewise laser irradiation, followed by floodwise exposure to produce an image in the photosensitive layer corresponding to the laser produced image. The outermost layers are removed and development provides a suitable negative-working printing plate.

Photosensitive element having integral thermally bleachable mask and method of use

Image-recording materials and image-recording carried out using these to produce an optical mask

Security of a distribution facility is maintained. Authorization information is read from a security optical card or other technology card presented by a person attempting to engage in a restricted activity within the distribution facility or gain access to the facility. An identity of the person is verified as corresponding to an identity of a cardholder to whom the security optical card was issued. It is confirmed that engaging in the restricted activity or gaining access by the cardholder is permitted in accordance with the authorization information. The person is then permitted to engage in the restricted activity or is given access.

Facility security with optical cards

Methods and devices are provided for reading optical cards. A housing has a slot for slidably receiving an optical card. The optical card has physical tracks with an arrangement of physical pits to define on optically encoded biometric. A light detector is fixed in position relative to the housing. An optical train is also fixed in position relative to the housing and is configured to provide optical paths between the light detector and the optical card as the optical card is slid along the slot. A biometric sensor is provided. A processor is coupled with the light detector and with the biometric sensor. The processor has programming instructions to compare a biometric measured by the biometric sensor with the optically encoded biometric read from the optical card with the light detector.

Authenticating optical-card reader

An orange colored photomask visually transmissive to yellow-orange light formed by heating an exposed and developed silver-halide emulsion coated photomask. At approximately 200° C., black silver in the photomask begins to show evidence of conversion to a transparent red material. At a temperature of 250° C. to 320° C., the black silver opaque images are rapidly converted to orange, visually transmissive images which are essentially opaque to the ultraviolet light used to expose photoresist covered silicon wafers, while clear areas remain clear.

Jerome Drexler

Papers

Method for making thermochromic photomasks