Stereolithography

Rapid Prototyping Model of Power Saw Cabinet Part as seen in Figures 6 and 7. Using the Stereolithography technique the part was modelled from a polymere. 

Sterculiagum Sterculic acid Sterculic acid [738-87-4] Sterculic acids Stereolithography Stereon... 

P. E. Jacobs, Rarpid Prototyping and Manufacturing. Fundamental of Stereolithography, Society of Manufacturing Engineers, Dearborn, Mich., 1992. 

Methods are used to produce the more costly rapid prototypes include those that produce models within a few hours. They include photopolymerization, laser tooling, and their modifications. The laser sintering process uses powdered TP rather than chemically reactive liquid photopolymer used in stereolithography. Models are usually made from certain types of plastics. Also used in the different processes are metals (steel, hard alloys, copper-based alloys, and powdered metals). With powder metal molds, they can be used as inserts in a mold ready to produce prototype products. These systems enable having precise control over the process and constructing products with complex geometries. 

As an example stereolithography is a 3-D rapid process that produces automatically simple to very complex shaped models in plastic. Basically it is a method of building successive layers across sections of pho-topolymerized plastics on top of each other until all the thin printed layers can be joined together to form a whole product. The chemical key to the process, photopolymerization, is a well established technology in which a photo initiator absorbs UV energy to form free radicals that then initiate the polymerization of the liquid monomers. The degree... 

Sodian R, Loebe M, Hein A, Martin DP, Hoerstrup SP, Potapov EV, Hausmann H, Lueth T, and Hetzer R. Application of stereolithography for scaffold fabrication for tissue engineered heart valves. ASAIO, 2002, 48, 12-16. 

Several maj or hearing aid manufacturers use a prototyping method - stereolithography (SLA) - to manufacture custom hearing aid shells for their in the ear products. 

DSM Somos has developed a composite stereolithography material incorporating nanoparticle technology - NanoForm 15120. It exhibits high mechanical performance including a modulus superior to 5 GPa, and a HDT superior to 132°C. 

Juodkazis S, Horyama M, Miwa M, Watanabe M, Mizeikis AMV, Matsuo S, Misawa H (2002) Stereolithography and 3D micro-structuring of transparent materials by femtosecond laser irradiation. In Panchenko VY, Golubev VS (eds) Seventh international conference on laser and laser-information technologies. SPIE Proc 4644 27-38... 

Miwa M, Douoka K, Yoneyama S, Tuchitani S, Kaneko YK (2005) Young s module control of the micro cantilever made by micro-stereolithography. In El-FatatryA (ed) MOEMS and miniaturized systems V. SPIE, Bellingham, pp 6-13. doi 10.1117/12.589197... 

Rapid prototyping or stereolithography or three-dimensional object curing is a photochemical process used to produce solid three-dimensional objects, such as models, masters, or patterns with any shape directly from a design. 

Rapid prototyping (or stereolithography or 3D object curing) is a photochemical process used to produce solid 3D objects such as models, masters or patterns of any shape, directly from a design generated on a computer. The computer is used to control the illumination system that builds up the object, usually by a rapid polymerization process. An important part of the design is that the object is sectioned... 

Besides the economy-based drivers, an important factor must be considered Certain products cannot be produced by any other process but UV/EB. The cases in point optical fibers, vinyl flooring, photoresists, stereolithography and more.2... 

Stereolithography The trend is to develop UV-curable materials that mimic engineering plastics, such as polycarbonate or ABS (see below). 

Stereolithography is simple in concept and it provides great economies for the design lab as well as for the modeling process. It also provides previously unrecognized challenges for the polymer photochemist, for it is entirely a laser-initiated technology, and the polymerization reactions take place to depths below a finitely thin surface layer. 

In stereolithography the positions of polymerization x and y are controlled by a mirrored scanner which reflects the laser onto the surface of the to-be-polymerized monomer at a point x,y and the z dimension is determined by the position of the elevator, as shown in Figure 5. During the polymerization z, the depth to which reaction occurs, is held constant through the use of a UV photoinitiator that bleaches either not at all or very slowly, relative to the rate of polymerization. 

Our use of bleachable photoinitiators to carry out polymerization at depth opens the possibility of controlling the vertical dimension photochemically rather than mechanically. We have used the photoreduction of Eosin by triethanolamine to sensitize the polymerization of multifunctional acrylates to demonstrate the principle. Irradiation is carried out at 514 nm with an Ar+ laser having a beam diameter of 1.4 mm. The volume of sample irradiated is a small fraction of the total, simulating the conditions found in stereolithography. Because of bleaching of the photoinitiator, the irradiation generates... 

Microfabrication was achieved by micro-stereolithography using a CW Ar+ laser (see Figure 1.164) [3],... 

An acrylic chip was fabricated by stereolithography without an assembly process such as bonding. This fabrication method is a 3D method by solidifying a photopolymerizable resin layer-by-layer via the scanning of a UV laser beam. A special double-controlled surface method was adopted in order to produce a smooth and transparent surface for high-quality optical detection [240]. 

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