The invention relates to the use of compounds of formulae (I) and/or (II) as colorless IR absorbers wherein M is Ni, Pd, Pt, Au, Ir, Fe, Zn, W, Cu, Mo, In, Mn, Co, Mg, V, Cr or Ti, X.sub.1, X.sub.2 and X.sub.3 are each independently of the others sulfur or oxygen, R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are each independently of the others hydrogen, NR.sub.7R.sub.8, unsubstituted or substituted C.sub.1-C.sub.18alkyl, C.sub.1-C.sub.18 alkyl wherein the alkylene chain is interrupted with oxygen, unsubstituted or substituted C.sub.1-C.sub.18alkenyl, unsubstituted or substituted aryl, unsubstituted or substituted arylalkyl or unsubstituted or substituted heteroarylalkyl, R.sub.2 and R.sub.8, each independently of the other, being unsubstituted or substituted C.sub.1-C.sub.18alkyl, unsubstituted or substituted aryl, unsubstituted or substituted arylalkyl or unsubstituted or substituted heteroarylalkyl, a further IR absorber optionally being added to the compounds of formulae (I) and (II). The invention relates also to novel dithiolene compounds of formulae (I) and (II) wherein X.sub.1 is oxygen and X.sub.2 and X.sub.3 are oxygen or sulfur. The invention relates furthermore to novel dithiolene compounds of formulae (I) and (II) wherein R.sub.1 to R.sub.6 arc NR.sub.7R.sub.8.

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Methods for ultrashort pulse laser processing of optically transparent materials. A method for scribing transparent materials uses ultrashort laser pulses to create multiple scribe features with a single pass of the laser beam across the material, with at least one of the scribe features being formed below the surface of the material. This enables clean breaking of transparent materials at a higher speed than conventional techniques. Slightly modifying the ultrashort pulse laser processing conditions produces sub-surface marks. When properly arranged, these marks are clearly visible with side-illumination and not clearly visible without side-illumination. In addition, a method for welding transparent materials uses ultrashort laser pulses to create a bond through localized heating. The ultrashort pulse duration causes nonlinear absorption of the laser radiation, and the high repetition rate of the laser causes pulse-to-pulse accumulation of heat within the materials. The laser is focused near the interface of the materials, generating a high energy fluence at the region to be welded. This minimizes damage to the rest of the material and enables fine weld lines.

A multi-section tubular member including a sleeve surrounding and bridging a joint between a first section and a second section of the tubular member, and a method of forming a multi-section tubular member are disclosed. A polymeric sleeve may extend over a portion of the first section and an adjoining portion of the second section. A length of heat shrink tubing may be placed over the sleeve and heated, thereby compressing the heat shrink tubing around the sleeve. The sleeve may then be thermally bonded to each of the first section and the second section. The heat shrink tubing may then be removed, leaving the sleeve securely joining the first section and the second section to form a multi-section tubular member.

An endless fabric belt for use in a paper, cardboard or tissue machine has machine-direction threads and cross-machine-direction threads. At least part of the threads are yarns composed substantially of a thermoplastic polymer material which is transparent for light of a wavelength. The fabric belt is a flat-weave with two front-side ends that are subsequently connected by bringing together end sections of the machine-direction threads in pairs with the formation of junction points and are woven with cross-machine-direction threads, forming a seam region. A material-to-material bond is formed in the seam region by absorbing light at the wavelength at yarn contact points. In the seam region, a plurality of spaced-apart, strip-shaped fabric sections are formed, in which the junction points and the yarn contact points which are connected to one another are arranged, and one strip-shaped fabric section without junction points is formed between two immediately adjacent fabric sections having the junction points.

A method for scribing transparent materials uses ultrashort laser pulses to create multiple scribe features with a single pass of the laser beam across the material, with at least one of the scribe features being formed below the surface of the material. This enables clean breaking of transparent materials at a higher speed than conventional techniques.

A method for producing a receptacle which is closed by a sheet by transmission laser welding, and to an apparatus suitable to carry out same. The method and the apparatus are configured in such a way that a weld seam is formed between the wall structure of the receptacle and the sheet so as to be wider than the end faces of the wall structure.

A multi-section tubular member including a sleeve surrounding and bridging a joint between a first section and a second section of the tubular member, and a method of forming a multi-section tubular member are disclosed. A polymeric sleeve may extend over a portion of the first section and an adjoining portion of the second section. A length of heat shrink tubing may be placed over the sleeve and heated, thereby compressing the heat shrink tubing around the sleeve. The sleeve may then be thermally bonded to each of the first section and the second section. The heat shrink tubing may then be removed, leaving the sleeve securely joining the first section and the second section to form a multi-section tubular member.

A method for scribing transparent materials uses ultrashort laser pulses to create multiple scribe features with a single pass of the laser beam across the material, with at least one of the scribe features being formed below the surface of the material. This enables clean breaking of transparent materials at a higher speed than conventional techniques.

A device and a method for performing and monitoring a plastic laser transmission welding process includes a processing beam source for emitting a processing radiation into a joining zone between two joining members so that a weld seam is formed, a measuring beam source for irradiating a measuring zone with a measuring radiation, a detection unit for detecting the measuring radiation reflected by an interface between the weld seam and its surroundings in the joining members, and an evaluation unit connected to the detection unit for determining the depth position of the interface in the joining members from the detected reflected measuring radiation.

Method for manufacturing a cell-like honeycomb structure, formed from a plurality of thermoplastic sheets attached to each other, wherein contoured areas are provided in each sheet, and each free sheet is attached to an adjacent sheet of an intermediate block formed by the different sheets previously attached therebetween, welding at least some of the flat areas contacting this free sheet and this adjacent sheet with a laser source along a continuous line parallel to the contour axis.