Laser marking on photosensitive material and photosensitive material including the marking

A laser marking method for forming a visible marking pattern on a photosensitive material, the method comprising the steps of:

• supplying a photosensitive material comprising a base layer having formed on a surface thereof an emulsion layer;
• irradiating a laser beam onto the emulsion layer to thereby generate air bubbles inside the emulsion layer;
• and
• stopping the irradiation of the laser beam at a point in time when the emulsion layer has become convex due to the generation of the air bubbles,
• whereby a convex dot pattern including plural minute air bubbles inside the emulsion layer is formed on the photosensitive material,
• wherein an irradiation time of the laser beam is controlled so that a height of the convex dot pattern formed on the surface of the emulsion layer of the photosensitive material is 10 μm or less from the surface and the minute air bubbles numerously formed inside the convex dot pattern have a diameter of 1 to 5 μm.

A laser marking method for forming a visible marking pattern on a photosensitive material, the method comprising the steps of:

• supplying a photosensitive material comprising a base layer having formed on a surface thereof an emulsion layer;
• irradiating a laser beam onto the emulsion layer to thereby generate air bubbles inside the emulsion layer;
• and
• stopping the irradiation of the laser beam at a point in time when the emulsion layer has become convex due to the generation of the air bubbles,
• whereby a convex dot pattern including plural minute air bubbles inside the emulsion layer is formed on the photosensitive material,
• wherein an oscillation wavelength of the laser beam is set to be from 9.2 μm to 9.8 μm.

A laser marking method for forming a visible marking pattern comprising a dot arrangement on a photosensitive material, the method comprising the steps of;

• supplying a photosensitive material comprising a support having formed on at least one side thereof an emulsion layer;
• setting a laser oscillator so that it is capable of irradiating a laser beam onto the emulsion layer;
• using the laser oscillator to irradiate the laser beam in a spot onto the emulsion layer to impart a predetermined amount of energy to the photosensitive material,
• wherein numerous air bubbles are generated inside the emulsion layer by the predetermined amount of energy being imparted within a predetermined time, to thereby form visible dots.

A laser marking method for forming a marking pattern on a photosensitive material by irradiating a laser beam onto the photosensitive material, the method comprising the steps of:

• conveying a photosensitive material in a predetermined conveyance direction;
• disposing a laser oscillator and a condenser so as to condense a laser beam emitted from the laser oscillator into a spot on a surface of the conveyed photosensitive material;
• and
• irradiating the laser beam through the condenser onto the photosensitive material so that the surface of the photosensitive material is positioned further away from the laser oscillator than a focal point of the laser beam converged by the condenser, whereby the marking pattern is formed on the photosensitive material.

A laser marking method for forming a marking pattern on a photosensitive material, the method comprising the steps of:

• supplying a photosensitive material comprising a support, a surface layer including an emulsion layer formed on one side of the support, and an undersurface layer formed on another side of the support to prevent diffuse reflection of light transmitted through the emulsion layer;
• and
• irradiating a laser beam in a sport onto the undersurface layer of the photosensitive material to generate air bubbles in the undersurface layer,
• whereby the marking pattern is formed on the undersurface layer of the photosensitive material.

A photosensitive material processing method for cutting a photosensitive material wound in a roll into a predetermined size to make sheets, the method comprising the steps of:

• pulling the photosensitive material out from a roll of the photosensitive material and conveying the photosensitive material along a predetermined path;
• irradiating a laser beam onto a recording position that is a predetermined distance from a position at which the conveyed photosensitive material is to be cut, to thereby form, on the photosensitive material, a marking pattern including identification information specifying the photosensitive material;
• and
• cutting the photosensitive material to a predetermined length along the conveyance path.

A photosensitive material processing device for cutting a photosensitive material wound in a roll into a predetermined size to make sheets, the device comprising:

• a conveyance mechanism for pulling the photosensitive material out from a roll of the photosensitive material and conveying the photosensitive material along a predetermined path;
• a laser beam oscillator for irradiating a laser beam onto the photosensitive material, the laser beam oscillator being disposed at a predetermined position on the conveyance path and forming, on the photosensitive material, a marking pattern including identification information specifying the photosensitive material by irradiating the laser beam onto a recording position that is a predetermined distance from a position at which the conveyed photosensitive material is to be cut;
• and
• a cutter for cutting the photosensitive material to a predetermined length along the conveyance path.

A laser marking method for forming a visible marking pattern on a photosensitive material, the method comprising the steps of:

• supplying a photosensitive material comprising a base layer having formed on a surface thereof an emulsion layer, wherein said emulsion comprises gelatin;
• irradiating a laser beam onto the emulsion layer to thereby generate air bubbles inside the emulsion layer;
• and
• stopping the irradiation of the laser beam at a point in time when the emulsion layer has become convex due to the generation of the air bubbles,
• whereby a convex dot pattern including plural minute air bubbles inside the emulsion layer is formed on the photosensitive material.