Abstract: The present invention relates to a process for preparing alkyl methacrylates and their conversion products which can be used in a multitude of chemical synthesis processes which can lead to a wide variety of different further processing products, and to an apparatus for performing this process.

Abstract: The present invention relates in general terms to a process for preparing alkyl methacrylates, comprising as steps: providing an acetone cyanohydrin by a process according to one of the preceding claims; contacting the acetone cyanohydrin with an inorganic acid to obtain a methacrylamide; contacting the methacrylamide with an alcohol in the presence of an inorganic acid in a reactor to obtain an alkyl methacrylate; continuously discharging at least a portion of the alkyl methacrylate from the reactor into a distillation column as a vapor stream; the discharge being effected by feeding a discharge stream comprising steam into the reactor, to an apparatus for preparing alkyl methacrylates, to a process for preparing polymers based at least partly on alkyl methacrylates, to the use of the alkyl methacrylates obtainable by the process according to the invention in chemical products, and to chemical products based on alkyl methacrylates obtainable by the process according to the invention.

Abstract: The present invention relates in general terms to a process for preparing acetone cyanohydrin, comprising as steps: A. contacting acetone and hydrocyanic acid in a reactor to give a reaction mixture, the reaction mixture being circulated, to obtain acetone cyanohydrin; B. cooling at least some of the reaction mixture by flowing it through a cooling region of a cooler, the cooler including one cooling element or at least two cooling elements; C.

Abstract: The invention relates in general terms to a process for preparing to a process for purifying an alkyl methacrylate, comprising the steps of: A. providing an alkyl methacrylate with an impurity: B. adsorbing at least some of the impurity onto a purifying solid to obtain an ultrapure alkyl methacrylate, to a process for preparing an ultrapure alkyl methacrylate, to an apparatus for preparing alkyl methacrylates, to a process for preparing a polymer based at least partly on alkyl methacrylates, to the use of an alkyl methacrylate obtained according to the invention in chemical products, and to chemical products comprising an alkyl methacrylate obtained according to the invention.

Abstract: The present invention relates in general terms to a process for preparing acetone cyanohydrin, comprising as steps: A. contacting acetone and hydrocyanic acid in a reactor to give a reaction mixture, the reaction mixture being circulated, to obtain acetone cyanohydrin; B. cooling at least some of the reaction mixture; C. discharging at least a portion of the acetone cyanohydrin obtained from the reactor; D. continuously distilling the discharged acetone cyanohydrin obtained to obtain an acetone cyanohydrin bottom product and an acetone top product in a distillation column; E. recycling at least a portion of the acetone top product into step A, the acetone top product being kept at less than 60° C.

Abstract: The invention relates to a process for preparing acetone cyanohydrin and to a process for preparing alkyl methacrylates, in which an acetone cyanohydrin as can be prepared in accordance with the present invention is used.

Abstract: The invention relates to a process for preparing acetone cyanohydrin and to a process for preparing alkyl methacrylates, in which an acetone cyanohydrin as can be prepared in accordance with the present invention is used.

Abstract: The present invention relates in general terms to a process for preparing acetone cyanohydrin, comprising as steps: A. contacting acetone and hydrocyanic acid in a reactor to give a reaction mixture, the reaction mixture being circulated, to obtain acetone cyanohydrin; B. cooling at least some of the reaction mixture; C. discharging at least a portion of the acetone cyanohydrin obtained from the reactor; D. continuously distilling the discharged acetone cyanohydrin obtained to obtain an acetone cyanohydrin bottom product and an acetone top product in a distillation column; E. recycling at least a portion of the acetone top product into step A, the acetone top product being kept at less than 60° C.

Abstract: The subject-matter of the present invention relates in principle to a process for preparing alkyl esters of methacrylic acid and its conversion products, which can be used in a multitude of chemical synthesis processes which can lead to a wide variety of different further processing products, and to an apparatus for performing this process.

Abstract: The present invention relates to a process for preparing alkyl methacrylates and their conversion products which can be used in a multitude of chemical synthesis processes which can lead to a wide variety of different further processing products, and to an apparatus for performing this process.

Abstract: The present invention relates in general terms to a process for preparing alkyl methacrylates, comprising as steps: providing an acetone cyanohydrin by a process according to one of the preceding claims; contacting the acetone cyanohydrin with an inorganic acid to obtain a methacrylamide; contacting the methacrylamide with an alcohol in the presence of an inorganic acid in a reactor to obtain an alkyl methacrylate; continuously discharging at least a portion of the alkyl methacrylate from the reactor into a distillation column as a vapour stream; the discharge being effected by feeding a discharge stream comprising steam into the reactor, to an apparatus for preparing alkyl methacrylates, to a process for preparing polymers based at least partly on alkyl methacrylates, to the use of the alkyl methacrylates obtainable by the process according to the invention in chemical products, and to chemical products based on alkyl methacrylates obtainable by the process according to the invention.

Abstract: The invention relates in general terms to a process for preparing to a process for purifying an alkyl methacrylate, comprising the steps of: A. providing an alkyl methacrylate with an impurity: B. adsorbing at least some of the impurity onto a purifying solid to obtain an ultrapure alkyl methacrylate, to a process for preparing an ultrapure alkyl methacrylate, to an apparatus for preparing alkyl methacrylates, to a process for preparing a polymer based at least partly on alkyl methacrylates, to the use of an alkyl methacrylate obtained according to the invention in chemical products, and to chemical products comprising an alkyl methacrylate obtained according to the invention.

Abstract: The present invention relates in general terms to a process for preparing acetone cyanohydrin, comprising as steps: A. contacting acetone and hydrocyanic acid in a reactor to give a reaction mixture, the reaction mixture being circulated, to obtain acetone cyanohydrin; B. cooling at least some of the reaction mixture by flowing it through a cooling region of a cooler, the cooler including one cooling element or at least two cooling elements; C.

Abstract: The invention relates to a process and a device for alignment of sheet material (1) which is conveyed in one conveyor plane (9). The sheet material is conveyed on bodies (35) of revolution and aligned by means of triggerable alignment elements (25) in the conveyor direction (22) and perpendicular to the conveyor direction (22). The alignment elements (25) are assigned to an alignment unit (8). The alignment motion necessary for alignment of the sheet material in the conveyor direction (2) and perpendicular thereto takes placed by separate alignment elements (25) which can be triggered independently of one another during conveyance of the sheet material (1) with the process speed.

Abstract: The invention relates to a method for the alignment of sheet-like material (1). Its alignment occurs via rotation elements (25), wherein the sheet-like material (1) is rotated around its central axis in order to print on the front and backsides. During the rotation of the sheet-like material (1) around its central axis, the material's leading edge (23) remains in its aligned position. Into the conveyor surface (9) is incorporated a sensor pair (30), preferably in the form of CCD line sensors, with which the sheet-like material (1) is aligned on the same lateral edge (24) following the rotation, as is the case during the alignment procedure of the sheet-like material (1) before it is rotated around its center axis.

Abstract: The invention relates to a process and a device for alignment of sheet material (1) which is conveyed in one conveyor plane (9). The sheet material is conveyed on bodies (35) of revolution and aligned by means of triggerable alignment elements (25) in the conveyor direction (22) and perpendicular to the conveyor direction (22). The alignment elements (25) are assigned to an alignment unit (8). The alignment motion necessary for alignment of the sheet material in the conveyor direction (2) and perpendicular thereto takes placed by separate alignment elements (25) which can be triggered independently of one another during conveyance of the sheet material (1) with the process speed.

Abstract: The invention relates to a process for compensation of dimension changes on sheet material (1) which is first provided with a printed image (36) on the front (35) and which is then provided with a printed image (40) on its back (39). The dimensions (41, 42) of the sheet material (1) are determined before an image is printed on the front (35) and before an image is printed on the back (39), and before an image is printed on the back (39) of the sheet material (1) the latter is centered to its position when the image was printed on the front (35).

Abstract: The invention relates to a method, apparatus and a printing machine (1) having a control device (8, 8′, 8″, 8′″) for the digital control of an element of the printing machine (1), an assignment (6, 6′) of two non-coincident digital variables (2 and 2′) being carried out.