Stable green phosphor and plasma display panel using the same

A method of producing a green emitting Mn and alkali metal activated lanthanide aluminate phosphor having the empirical formula:

• Ln(2-x-y)B22O36:Mnx.Ay
• wherein:
• Ln is a combination of La, Y, Gd, and Tb, wherein La is:
• 0.57≦La≦1.782;
• Y is:
• 0≦Y ≦0.19;
• Gd is:
• 0.198≦Gd≦0.95;
• and Tb is:
• 0≦Tb≦0.19;
• A is selected from the group consisting of:
• Li, Na, K and a combination thereof;
• B is selected from the group consisting of:
• Al and a combination of Al and Ga;
• x is from about 0.01 to about 0.1;
• and
• y is from about 0.01 to about 0.1;
• wherein said method comprises the steps of:
• mixing a source of an alkali metal, a source of manganese, a source of lanthanide and a source of aluminum in an acid medium to form dilute aqueous solution;
• removing at least a portion of water from said dilute aqueous solution to form a gel;
• heating said gel at a temperature sufficient to remove excess water thereby converting said gel into a gel powder;
• and
• thermally decomposing said gel powder at a temperature and for a length of time sufficient to produce said phosphor.

A phosphor material for a plasma display panel comprising a composition represented by the formula:

• Ln(2-x-y)B22O36:MnxAy
• wherein:
• Ln is a combination of La, Y, Gd, and Tb, wherein La is:
• 0.57≦La≦1.782;
• Y is:
• 0≦Y≦0.19;
• Gd is:
• 0.198≦Gd≦0.95;
• and Tb is:
• 0≦Tb≦0.19;
• A is selected from the group consisting of:
• Li, Na, K and a combination thereof;
• B is selected from the group consisting of:
• Al and a combination of Al and Ga;
• x is from about 0.01 to about 0.1;
• and
• y is from about 0.01 to about 0.1;
• which phosphor emits green light when excited by vacuum ultra violet light of wavelength in the range of 100 nm to 200 nm.

An improved plasma display panel, having a front plate with electrodes, dielectric layer, a thin protecting layer (MgO), a back plate with electrodes, reflective layer, ribs, phosphors, and a plurality of discharge spaces filled with a gas mixture between said front plate and said back plate, wherein said gas mixture comprises 5 to 50% Xe, and 50 to 95% Ne, wherein the improvement comprises:

• a plasma display panel which includes a green emitting phosphor material comprising a composition represented by the formula:
• Ln(2-x-y)B22O36:MnxAy
• wherein:
• Ln is a combination of La, Y, Gd, and Tb, wherein La is:
• 0.57≦La≦1.782;
• Y is:
• 0≦Y≦0.19;
• Gd is:
• 0.198≦Gd≦0.95;
• and Tb is:
• 0≦Tb≦0.19;
• A is selected from the group consisting of:
• Li, Na, K and a combination thereof;
• B is selected from the group consisting of:
• Al and a combination of Al and Ga;
• x is from about 0.01 to about 0.1;
• and
• y is from about 0.01 to about 0.1;
• which phosphor emits green light when excited by vacuum ultra violet light of wavelength in the range of 100 nm to 200 nm.

A solvent free method of producing a green emitting Mn and alkali metal activated lanthanide aluminate phosphor having the empirical formula:

• Ln(2-x-y)B22O36:MnxAy25
• wherein:
• Ln is a combination of La, Y, Gd and Tb, wherein La is:
• 0.57≦La≦1.782;
• Y is:
• 0≦y≦0.19;
• Gd is:
• 0.198≦Gd≦0.95;
• and Tb is:
• 0≦Tb≦0.19;
• A is selected from the group consisting of:
• Li, Na, K and a combination thereof;
• B is selected from the group consisting of:
• Al and a combination of Al and Ga;
• x is from about 0.01 to about 0.1;
• and
• y is from about 0.01 to about 0.1;
• wherein said method comprises the steps of:
• mixing a source of an alkali metal, a source of manganese, a source of lanthanide and a source of aluminum to form a powder mixture;
• and thermally decomposing said powder mixture at a temperature and for a length of time sufficient to produce said phosphor.