TO INCREASE PROCESSING EFFICIENCY, TO SAVE ENERGY AND PRODUCTION COSTS, AND TO INCREASE PRODUCT YIELD

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2 TO INCREASE PROCESSING EFFICIENCY, TO SAVE ENERGY AND PRODUCTION COSTS, AND TO INCREASE PRODUCT YIELD LIMS (Liquid Injection Molding System) is a newly designed system, which includes a series of highly functional liquid silicone rubbers and an injection molding machine to precisely inject those fluids. From the set-up of raw materials to blending and molding, the entire process is automated to secure high quality products. Because the raw materials are liquid silicone rubbers, which exhibit excellent properties, they meet a wide range of requirements in the electrical, electronic, automotive and food industries. LIMS saves energy and increases productivity. LIQUID SILICONE RUBBERS High speed curing Long pot life Low viscosity Good release properties High tear strength MOLDS Cold-runner Flashless Runnerless INJECTION MOLDING MACHINE Accurate extruded amounts Stable shot PUMPS Metering with precision 1

3 EXCELLENT PROPERTIES Liquid silicone rubbers are highly functional rubbers with heat resistance, electrical insulation, high strength, flame resistance and electric conductivity, and can produce not only transparent goods but also a wide variety of colored products. SAVING PROCESSING TIME The curing of liquid silicone rubbers is an addition reaction. The curing speed is rapid, saving significant processing time. AUTOMATING INJECTION MOLDING PROCESS Good molding characteristics. Excellent release properties after curing. The entire Process can be automated. NO ENVIRONMENTAL POLLUTION The curing reaction produces no by-products. If flashless and runnerless molds are used, the treatment of cured waste materials are eliminated. INCREASING PRODUCT YIELD Because the raw materials are liquid silicone rubbers, which can be injected at low pressure, they are suitable for molding precision parts. The components of A and B can be accurately blended at an accurate ratio, to secure high quality products. 2

4 LIMS are liquid silicone rubbers, which exhibit excellent heat resistance, electrical insulation, radiation resistance and corona resistance of conventional silicone rubbers. Shin-Etsu provides a number of LIMS grades for use in a wide range of applications such as general-purpose, high strength, transparent and flame resistant types. We continue to develop new products to meet specific requirements of our customers. KE2000 Series These products are highly transparent, high-strength and fast curing types of silicones, available in a range of hardnesses from 20 to 60. Because of molding with flashless and runnerless molds, automation with short cycle is possible. KE1950 Series These products are transparent and high-strength silicones, available in the range of hardnesses from 10 to 70. General Properties Items Before curing After curing * 2 Viscosity* 1 products Liquid A Liquid B Liquid A Liquid B Specific gravity at 23 C (73.4 F) Hardness, Durometer type A Tensile strength MPa Elongation at break % Tear strength, crescent type kn/m Compression set * 3 % Linear shrinkage % Volume resistivity TΩ m Fast curing, highly transparent, high strength KE (A B) KE (A B) KE (A B) KE (A B) KE (A B) KE (A B) Translucent Translucent Translucent Translucent Translucent Translucent Translucent Translucent Translucent Translucent Translucent Translucent , , Transparent Transparent Transparent Transparent Transparent Transparent Items Before curing After curing* 2 Viscosity* 1 Pa s products Liquid A Liquid B Liquid A Liquid B Specific gravity at 23 C(73.4 F) Hardness, Durometer type A Tensile strength MPa Elongation at break % Tear strength, crescent type kn/m Compression set % Linear shrinkage % Volume resistivity TΩ m Transparent, high strength KE (A B) KE (A B) KE (A B) KE (A B) KE (A B) KE (A B) Translucent Translucent Translucent Translucent Translucent Translucent Translucent Translucent Translucent Translucent Translucent Translucent Transparent Transparent Transparent Transparent Transparent Transparent *1 Brookfield-type rotational viscometer *2 5 minutes press-curing at 120 C(248 F) 1 hour post-curing at l50 C(302 F) 3

5 KE1990 Series These products are general-purpose silicones, available in hardness of 40, 50, and 60. They are designed primarily for use in keypad applications. KE meets the standards of UL 94HB, KE and KE are equivalents of UL 94HB. KE1955 (A B) This product is a flame resistant silicone, it meets the standards of UL V-0. KE1935 (A B), KE 1987 (A B), KE 1988 (A B) These materials are suitable for making highly transparent products. KE2010(A B), KE2011 (A B), KE1995 (A B) These products are oil resistant types, KE1995 is qualified under JIS B type C (O-rings). PIGMENTS FOR COLORING LIMS SILICONE RUBBERS The following pigments are for coloring LIMS materials, Oil-bleed pigments are also available. PIGMENTS FOR OIL BLEED PIGMENTS Products Color Products Color LIMS Color-01 Black LIMS Color-02 Black LIMS Color-03 Reddish brown LIMS Color-04 Orange LIMS Color-06 Brown LIMS Color-05 Grayish-green *Please contact us for other colors of pigments. products Highly transparent, high strength General purposes Flame resistant Items KE (A B) KE (A B) KE (A B) KE (A B) KE (A B) KE1955 (A B) Before curing After curing* 2 Liquid A Liquid B Viscosity* 1 Liquid A Pa s Liquid B Specific gravity at 23 C(73.4 F) Hardness, Durometer type A Tensile strength MPa Elongation at break % Tear strength, crescent type kn/m Compression set % Translucent Translucent Translucent Translucent Transparent Transparent Translucent Translucent Translucent Translucent Translucent Translucent Translucent Translucent Translucent Black Black Black Linear shrinkage % Volume resistivity TΩ m products Highly transparent Oil resistant Items KE1935 (A B) KE1987 (A B) KE1988 (A B) KE2010 (A B)* 4 KE2011 (A B) KE1995 (A B) Before curing After curing* 2 Liquid A Liquid B Viscosity* 1 Liquid A Pa s Liquid B Specific gravity at 23 C(73.4 F) Hardness, Durometer type A Tensile strength MPa Elongation at break % Tear strength, crescent type kn/m Compression set % Transparent Translucent Translucent Transparent Translucent Translucent Transparent Transparent Transparent Gray Gray Reddish brawn Gray Gray Reddish brawn 800 1, , Gray Gray Reddish brawn Linear shrinkage % Volume resistivity TΩ m *3 5 minutes press-curing at 120 C(248 F) 4 hours post-curing at 200 C(392 F) *4 Oil bleed type *5 According to JIS 6249 testing method (not specified values) 4

6 1. Curing Temperature Although the optimum curing temperature varies with the thickness and shape of the product, standard temperatures range from 130 C (266 F) to 200 C (392 F), but curing is possible at temperatures as low as 90 C (194 F) and as high as 210 C (410 F). 2. Injection Pressure Optimum results are obtained at a curing temperature of 130 C (266 F) C (392 F), at pressure ranging from 40 kg/cm 2 to 120 kg/cm Curing Time Products can be molded in a very short cycle, no more than 10 seconds per millimeter thickness at 150 C (302 F). 4. Apparent Viscosity Apparent viscosity varies with shear rate, the relationship is indicated by a straight line on a logarithmic graph (please refer to Figure: Viscosity on page 6). 5. Linear Shrinkage Linear shrinkage ranges from 2% to 3% at temperatures between 100 C (212 F) to 150 C (302 F). (please refer to the table of General Properties on page 3-4). 6. Pot Life Pot life after mixing the components of A and B varies with temperatures. Typically, the viscosity remains constant for 72 hours at room temperature (25 C (77 F)). To extend the pot life, a chiller (a cooling device) set in the mixing section is recommended. Curing Mechanism Curing of liquid silicone rubber occurs by an addition reaction as illustrated below. The cure rate is accelerated when the materials are heated. CH3 CH3 OSiCH2CH2Si- CH3 OSi- CH=CH2+H- Si- CH3 CH3 O CH3 CH3- Si- H+CH2=CH- SiO Pt CH3 O CH3 CH3- SiCH2CH2SiO O CH3 CH3 O CH3 CH3 OSi- CH=CH2+H- Si- CH3 CH3 OSi- CH2CH2- Si- CH3 CH3 5

7 VISCOSITY AND CURING CHARACTERISTICS OF KE (A B) Viscosity Pot Life vs. Viscosity C (77 F) Common silicone KE951-U 25 C (77 F) C(77 F) Viscosity(Pa s) C(248 F) 150 C(302 F) Viscosity(Pa s) C(41 F) 180 C(326 F) Shear rate (1/sec) days Flow Tester: l.0 X 10 mm L Curing Characteristics Molding Temperature vs. Curing Time 150 C(302 F) Torque (MPa) KE KE Curing time (sec) (T10) Time : min. 1/T (X10-3 K -1 ) 6

8 Molding machines corresponding to viscosity ranges of liquid silicone rubbers (50-2,000 poise) at room temperature, should be used. Basically, the injection molding system includes a quantitative delivery pump and a dynamic or static mixer. There are compact injection molding machines especially designed for high precision LIMS (Please contact Shin-Etsu for details). Basic Design of LIMS Molding Machine Metering discharge pump Components A and B are metered accurately at a 1:1 ratio by a pressure pump and discharged. Injector Pressure and injection velocity are set (LIMS silicones can be molded at a very low injection pressure). Material feeder pump Pails (or drums) of components A and B are set and feed into the pump. Mold Mixer The components are mixed thoroughly by a dynamic or static mixer, and injected by pressure directly into the mold. A P B P(Pigments):option Shut-off nozzle A shut-off mechanism prevents material leaking from the nozzles. Mold closing The closing and opening of the mold die are operated sequentially with the feeder pump, the metering pump and the injector. 7

9 ADVICE FOR SYSTEM DESIGN Proper selection of seals for injection machinery is essential to the ultimate performance of the system. For example, nitride steel or ceramics should be used for sliding or rotating contacts where there is a potential for metal-to-metal contact. To avoid seepage of materials, 1-3 ply Teflon packing are recommended. Because of the liquid nature of the raw materials, molds voids should be tightly sealed to prevent leakage. Abrasion resistant materials should be used for mechanical parts (mixer and mold die) to avoid wear caused by the filler in liquid silicone rubbers. It is important that there are no dead spaces where silicones can accumulate in the shut-off nozzles, clamps and molds after the mixing process occurs. Liquid silicone rubbers are compressed liquids. Flow control of each component is necessary when molding. The mold should be equipped with at least one vent for quick air release. Please contact us for the other details. MOLDING DEFECTS, CAUSES AND COUNTER-MEASURES Defects Causes Countermeasures Blisters Voids Rough surfaces Uneven color Weld marks Poor luster Poor mold releasing Leakage from nozzles Incomplete curing Incomplete curing Insufficient molding pressure Entrapped air Uneven heating Incomplete curing Insufficient air vent Entrapped air Excess temperature of metal mold Incomplete mixing Fluctuation in mixing ratio or incomplete mixing Improper molding pressure Excess injection time Poor air vent at fused part Defective gate port Incomplete curing Rough surface of metal mold Improper curing conditions Defective surface condition of metal mold Uneven distribution of surface temperature Wear and incision on nozzles Curing inhibition Improper mixing ratio Extend curing time and increase temperature Increase pressure Vent the pails completely and adjust injection velocity Adjust heating unit Extend curing time Vent the pails completely Prevent air entrapment during injection Decrease temperature of metal mold, control temperature distribution of metal mold Adjust injection velocity, and check the mixer Adjust volume mixer and injection velocity Increase the pressure and decrease the temperature Decrease injection time Provide air vent Balance gate Extend curing time, increase temperature of metal mold Use polished metal mold with hard chromium plating and apply proper quantity of release agent. Extend curing time Repair metal mold Check the heating method Check nozzles Eliminate curing inhibition materials Check the mixing system 8

10 FOR GENERAL PURPOSES Primer No. 4 Primer No. 4 is a general use primer, because of its low viscosity, it is easy to handle and has excellent drying property. How to apply Apply the primer to the metal either by brushing, dipping or spraying. Wait about 15 minutes at room temperature after the primer is applied. Pot life is 24 hours after the primer is applied. General properties of Primer No. 4 Product Primer No. 4 light yellow, transparent Viscosity mm 2 /s Specific gravity Non-volatile matter 6-8% Solvent Ligroin Pot life 24 hours Drying Air drying for l5 minutes FOR BONDING TO PLASTICS Primer X Premier X is especially good for bonding to plastics, and it can either be air dried or oven baked. How to apply It can be applied by either dipping, brushing or spraying. Primed inserts may be used after 30 minutes of air drying at room temperature. Adhesion is improved, if the inserts are baked in an oven at 80 C(176 F) C(248 F) for minutes after 30 minutes of air drying. Pot life is 24 hours after the primer is applied. Containers should be kept in a cool and dark place. The solvent used as a diluent should be handled with caution. The General Properties of Primer X Product Primer X light yellow Viscosity mm 2 /s Specific gravity Non-volatile matter 3-5% Pot life 24 hours 9

11 Quality 1. Materials such as amines, sulfur, organic phosphorus compounds or organic tin compounds may cause curing inhibition of liquid silicone rubber. A preliminary curing test is recommended. Materials that may cause curing inhibition. Chloroprene and other synthetic rubbers Sulfur compounds Plasticized polyvinyl chloride resins Amine cured epoxy resins PVC insulating tapes Resin containing soldering fluxes 2. Liquid silicone rubbers should be stored in a cool and dark place, away from rain or humidity. Safety Guide 1. When using LIMS materials in medical appliances or food equipment, users should confirm that they conform to appropriate regulations. 2. If LIMS materials contact the skin, wipe them off immediately and clean the area with soap. 3. If the materials get into eyes, wash them immediately with a large amount of water and see an eye doctor if necessary. 4. Contact of component B with alkali substance may cause the evolution of flammable hydrogen gas. Precautions should be taken to prevent this. 5. Please contact our sales division for material safety data sheets (MSDS). PACKING Products KE (A B) KE (A B) KE (A B) KE (A B) KE (A B) KE (A B) KE (A B) KE (A B) KE (A B) KE (A B) KE (A B) KE (A B) KE (A B) KE (A B) KE (A B) KE (A B) KE (A B) KE1955(A B) KE1935(A B) KE1987(A B) KE1988(A B) KE2010(A B) KE2011(A B) KE1995(A B) Packing 18-liter can 180-liter drum 18 kg 20 kg 180 kg 200 kg 10

12 Silicone Division, Overseas Planning and Administration Department 6-1, Ohtemachi 2-chome, Chiyoda-ku, Tokyo, Japan Phone : +81-(0) Fax : +81-(0) Shin-Etsu Silicones of America, Inc Damar Drive, Akron, OH 44305, U.S.A. Phone : Fax : Shincor Silicones, Inc Evans Avenue, Akron, OH 44305, U.S.A. Phone : Fax : Shin-Etsu Silicones Europe B. V. Bolderweg 32, 1332 AV, Almere, The Netherlands Phone : +31-(0) Fax : +31-(0) Shin-Etsu Silicone Taiwan Co., Ltd. 7F, No.102, Civil Boulevard, Sec.4, Taipei, Taiwan R.O.C. Phone : +886-(0) Fax : +886-(0) Shin-Etsu Silicone Korea Co., Ltd. International Insurance Bldg. 904, 120, 5-ka, Namdaemoon-ro, Chung-ku, Seoul, Korea Phone : +82-(0) Fax : +82-(0) Shin-Etsu Singapore Pte. Ltd. 150 UBI Avenue 4, #03-00, Singapore Phone : Fax : Shin-Etsu Chemical Co., Ltd. Shanghai Liaison Office 2211 Shui On Plaza, 333 Huaihai Zhong Road, Shanghai, China Phone : +86-(0) Fax : +86-(0) The data and information presented in this catalog may not be relied upon to represent standard values. Shin-Etsu reserves the right to change such data and information, in whole or in part, in this catalog, including product performance standards and specifications without notice. Users are solely responsible for making preliminary tests to determine the suitability of products for their intended use. Statements concerning possible or suggested uses made herein may not be relied upon, or be construed, as a guaranty of no patent infringement. The silicone products described herein have been designed, manufactured and developed solely for general industrial use only; such silicone products are not designed for, intended for use as, or suitable for, medical, surgical or other particular purposes. Users have the sole responsibility and obligation to determine the suitability of the silicone products described herein for any application, to make preliminary tests, and to confirm the safety of such products for their use. Users must never use the silicone products described herein for the purpose of implantation into the human body and/or injection into humans. Users are solely responsible for exporting or importing the silicone products described herein, and complying with all applicable laws, regulations, and rules relating to the use of such products. Shin-Etsu recommends checking each pertinent country s laws, regulations, and rules in advance, when exporting or importing, and before using, the products. Please contact Shin-Etsu before reproducing any part of this catalog. Copyright belongs to Shin-Etsu Chemical Co., Ltd. JAB CEARTIFICATE No.R003 JAB CEARTIFICATE No.RE006 C Shin-Etsu / B.P. Printed in Japan.