This bulb is a classic 'Daylight' or 'True Light' incandescent bulb with a coiled tungsten filament, made by Philips and sold in Mexico in the past. Most incandescent daylight bulbs available these days are of the Neodymium type, which have a purplish tinge rather than this deep blue hue. I have seen blue daylight bulbs that were made as far back as the 1910's (I have a few of those in my collection), although I'm not sure about the exact date they were invented. This is a modern version made in the 90's. It's just a regular incandescent bulb with tinted glass. Now that we have LED bulbs that produce convincingly natural colors, there is no commercial reason left for blue bulbs like these to exist. The last time I saw these in store shelves in Mexico was in 2005. They are likely long gone, much like incandescent tungsten bulbs in general.