Heating element for high-speed film-sealing apparatus, and method for making same

A heating element for a film-sealing apparatus, comprising:

• a heating wire segment having opposite first and second ends, the heating wire segment being formed of a first metal having a first reflectance to laser radiation of a predetermined wavelength, the heating wire segment having a first electrical resistance;
• a first conductor lead comprising a wire having one end joined to the first end of the heating wire segment and an opposite end for connection to an electrical current supply;
• a second conductor lead comprising a wire having one end joined to the second end of the heating wire segment and an opposite end for connection to the electrical current supply;
• the first and second conductor leads each having an electrical resistance lower than the first electrical resistance of the heating wire segment such that a predetermined electrical current passed through the heating element causes the heating wire segment to be heated to a sealing temperature at which film plies placed in contact with the heating wire segment are heat-sealed together while the conductor leads remain below the sealing temperature;
• and
• the first and second conductor leads each being formed of a second metal having a second reflectance to laser radiation of said predetermined wavelength, the second reflectance being higher than the first reflectance, each of the first and second conductor leads being lap-welded to the respective end of the heating wire segment using laser radiation of said predetermined wavelength.