A system for holding a workpiece in position and exposing it to laser radiation, such that: the workpiece includes a bottom surface and a top surface that are electrically insulated from each other. The system includes an electrostatic charge generating device for generating electrostatic charges on the top surface; an electrically conductive support for forming, on the bottom surface, electrostatic charges of opposite sign to those generated on the top surface; and a laser device for machining or welding. The electrostatic charge generating device is arranged to be activated before or during the laser machining or welding, such that the workpiece is held in position relative to the electrically conductive support during the machining or welding thereof.

A method for producing a joined body of different materials. In the joined body, a plurality of resin layers may be joined together and a resin layer may be joined with a metal layer. A joined body of different materials.

The invention relates to a device comprising a first fixing element, a further fixing element and a folded planar composite; wherein the first fixing element comprises a first fixing surface and the further fixing element comprises a further fixing surface; wherein the folded planar composite is at least partially fixed between the first fixing surface and the further fixing surface; wherein the folded planar composite comprises a first composite region; wherein the first composite region comprises a first layer sequence comprising a first composite layer comprising a first carrier layer, a second composite layer comprising a second carrier layer, a third composite layer comprising a third carrier layer and a fourth composite layer comprising a fourth carrier layer; wherein in the first composite region the second composite layer is joined to the third composite layer and the third composite layer is joined to the fourth composite layer; wherein in the first composite region the third carrier layer is characterised by a smaller layer thickness than in each case one selected from the group consisting of the first carrier layer, the second carrier layer and the fourth carrier layer or a combination of at least two of these; wherein the first fixing surface or the further fixing surface or both comprises a recess comprising a first recess region; wherein the first composite region is located at least partially between the first recess region and the first fixing surface or the further fixing surface.

Laser transparent compositions that may be black in color. The laser transparent compositions may include a matrix material that includes a polypropylene, a dye system that includes one, and optionally two or more, polar organic compounds, a plurality of glass fibers, and a UV stabilizer. Methods of laser welding, which may include irradiating a laser absorbing composition that contacts a laser transparent composition at an interface.

A device comprising a first fixing element, a further fixing element, and a folded planar composite is disclosed. The first fixing element comprises a first fixing surface and the further fixing element comprises a further fixing surface. The folded planar composite is at least partially fixed between the first fixing surface and the further fixing surface. The folded planar composite comprises a first composite region and a further composite region.

A joint structure comprising a light-absorbable member having at least one opening portion and a light-permeable member superposed on the light-absorbable member so as to cover the opening portion, wherein an annular weld part is formed so as to enclose the opening portion and join the light-absorbable member and the light-permeable member, and an area ratio of a portion at the side of the light-absorbable member to a portion at the side of the light-permeable member side is in a range of 12-35 viewing a section perpendicular to the extending direction of the annular weld part.

A laminate of the present invention includes a first member which contains a thermoplastic polymer and through which laser light is transmitted and a second member which contains a thermoplastic polymer and absorbs laser light, wherein the first member is directly bonded to the second member, and A represented by the formula 1: A=9D+Wa45 is more than zero. D represents a distance between a Hansen solubility parameter of the thermoplastic polymer of the first member and a Hansen solubility parameter of the thermoplastic polymer of the second member, and Wa represents work of adhesion calculated from each surface free energy of the first member and the second member. Such a first member and a second member are firmly bonded to each other without using a bonding sheet.

Plastic parts are welded in a laser welding system. An infrared laser source in a laser chamber is controlled by a controller using closed-loop feedback control with a corrected feedback signal that is compensated for background infrared radiation in the laser chamber. Prior to the infrared laser source being turned on, the controller senses with the optical sensor an intensity of background infrared radiation in the laser chamber. Once the laser is on, the controller senses with the optical sensor an intensity of infrared laser radiation in the laser chamber. The controller calculates the corrected feedback signal by subtracting the intensity of the background infrared radiation sensed when the infrared laser source was off from the intensity of the infrared laser radiation sensed when the infrared laser source is on.

Plastic parts are welded with a true 3D volumetric weld using intersecting multi-beam trace laser welding in which a plurality of spot laser beams having the same wavelength are directed to the so that the laser beams intersect each other at a point along a weld path within one of the plastic parts at an angle in an intersection angle range between ten degrees and ninety degrees. The plurality of laser beams are traced so that the intersection of the plurality of laser beams traces along the weld path to form a weld pattern that is linear, curvilinear, planar or three dimensional along a joint that is inside a volume of plastic. The plastic part in which the laser beams intersect is partially absorptive to laser light at a wavelength and the laser beams have this wavelength.

A container sealing apparatus including: a rotating spindle (24); a rotating turret means (38) disposed around the rotating spindle and having pockets (40) along a circular transport path; container support means (42) arranged below the rotating turret means in correspondence with the pockets (40), and which can rotate about the rotating spindle and rotate on their axes; lid pressing means (44) arranged above the rotating turret means in correspondence with the container support means, which can rotate about the rotating spindle and rotate on their axes, and can ascend and descend relative to the container support means; and laser irradiation means (46) capable of rotating about the rotating spindle and adapted to direct laser light toward the container (2), against which the lid (14) has been pressed by the container support means and the lid pressing means, thereby heat welding the lid (14) to the container.