Suppliers of membrane switches highlight selections with added features to cater to various requirements in consumer electronics and industrial applications.

Piggybacking on robust demand and a broadening application base, makers of membrane switches in China are enhancing product features to establish a foothold in target markets. Suppliers are adding anti-UV and water-resistant capability, embedded LED, EL backlight, electric shielding layer, and window and lens coating. Switches with high temperature capacity are also offered on request.

Besides consumer electronics and home appliances such as microwave ovens, releases from China are used in industrial setups. Models are designed for testing and medical equipment, industrial controllers, and textile manufacturing, building safety and train operation control systems. Entries for the last can withstand harsh environments and resist abrasion, solvents, moisture and UV radiation.

In addition to enhancing features and functions, makers are improving production techniques to match buyers’ requirements. Advanced equipment is utilized to speed up processes and cut labor costs. Enterprises use machines for computerized color matching, precision screen-printing, finishing, die cutting and assembly. Beijing Membrane Switch Manufacturer Co. Ltd reduced outlay by 30 to 50 percent after acquiring high-precision digital printing and laser cutting machinery.

Growing adoption of the component boosted China makers’ sales by more than 10 percent in 2010. Tada Membrane Switch Co. Ltd posted at least 30 percent jump in revenue, and anticipates another 20 percent rise this year. It will increase workforce by 20 percent to meet growing orders.

Meanwhile, Shenzhen M-Tech Co. Ltd, which registered 20 percent growth, plans to add a new production line with a Heidelberg printing equipment. It will likewise set up a dust-resistant workshop this year.

The country’s manufacture pool is made up of about 100 players, with nearly 80 percent based in Shenzhen, Guangdong province. The city’s mature support chain continues to attract enterprises.

The other hubs are Shanghai and Beijing, and the provinces of Zhejiang, Fujian and Jiangsu. Makers focus on
OEM transactions, which typically comprise small and midsize orders. Manufacturers such as Shenzhen Lunfeng and Shenzhen Xin Jie Jia have started to export their selections to take advantage of rising global demand. They are also taking part in trade fairs abroad to boost market presence. Shanghai Shanben participates at the China Sourcing Fair in Hong Kong every year to showcase latest models, which cater to overseas partners such as Ericsson, GE, Tyco and Nokia. The enterprise also provides large-scale membrane switches to BaoSteel, Foxconn and Delta.

Several mainland China providers are venturing into other markets, among which is Beijing MembraneSwitch. The supplier plans to attend seminars and exhibitions in North America this year under efforts to draw orders from the area.

Tactile, nontactile membrane switches

Membrane switches from China can be classified into tactile and nontactile or 28flat based on production technique. For the first, there are metal and poly dome types, with the last boasting greater durability.

Tactile variants are more commonly used, while nontactile kinds are suitable for applications requiring large, hidden or irregularly shaped keys at lower costs. Shenzhen Lunfeng’s szlf60-007 model is a nontactile membrane switch with metal domes.

Mainstream variants have a thickness of 0.1, 0.15, 0.175, 0.2, 0.25, 0.3, 0.5, 0.7 or 1mm.

Releases with touch panels or LCD screens are becoming popular. Tada has such categories, which can integrate LED backlighting and PC layers on request. The dielectric withstand voltage is typically 250V rms at 50/60Hz for 1min, while the contact bounce is 5ms. Flat types can last 5 million cycles, and tactile varieties 1 million.

EL backlight and storelight membrane switches constitute Shenzhen M-Tech’s selection. These are used in dark environments, lamplights and keyboards. The company’s MS-09-1 model delivers 35VDC operating voltage and 100mA operating current, and can withstand 250V rms dielectric voltage at 50/60Hz. The 11.5×8.5×0.01in unit has less than 100Mohm at 100VDC and 10 to 500ohm insulation and contact resistance, respectively.

Membrane switches from China can come with FPC and ESD/EMI shielding layers. Types integrating the former can be easily soldered and designed with a smaller pin distance.

Graphic panels can incorporate a variety of subpanels, including PCB, and aluminum and plastic boards. Switches featuring the first can support more complex circuit designs.

Silicone rubber membrane switches are applied in mobile phones. The embossed keys are available in various shapes or as specified by clients. Logos, meanwhile, adopt a diamond or zebra cut.

China manufacturers ensure that models comply with RoHS.

The different parts of membrane switches entail various materials. For the overlay or top layer, which contains the printed user interface, makers employ PET, PC or PVC. Types featuring the first offer a longer life span, more actuations and better resistance. The input is sourced from DuPont or Bayer. While PC is less expensive, it may compromise durability.

Metal or poly domes make up the top circuit. For the former, there are gold and stainless steel. Gold-plated domes, which can be substituted with nickel or silver, provide better contact performance.

Manufacturers use aluminum or PC subpanel for the backing layer, and bond them through adhesive. For the rear adhesive, suppliers adopt inputs from 3M or Nikko. The electronic circuit sheet can be in PET, PCB and FPC, while the tail may feature clear or green mask.

Companies obtain LED, PCB, FPC, EL and touch panels from local partners. For the last, four or five-wire resistive units or capacitive versions are employed in high-end models. Connectors can be ZIF, female and male types.

The other materials are color and UV dielectric ink, which can be sourced from Jujo Chemical, Bayer or Acheson.

Suppliers purchase 90 percent of raw materials from overseas providers. Costs increased 5 to 10 percent in 2010.

A number of enterprises produce components in-house. Shenzhen Lunfeng turns out FPCs, stickers and touchscreens, while Tada manufactures touch panels in its Zhejiang province factory.

Prices of membrane switches are projected to remain stable, although some makers plan to raise quotes by 1 to 5 percent.

Taiwan: Membrane switch line targets office automation, ICT applications

Taiwan’s membrane switch makers are focusing on models suitable for office automation and ICT applications. They are turning out flat, pillow, spherical and rim embossed, and poly, metal and Mylar dome kinds. Selections find use in mobile and landline phones, PDAs, medical equipment, industrial apparatuses and ATMs.

More than 90 percent of rollouts are customized. Manufacturers are integrating new features to satisfy buyers’ requirements, with touchscreen currently the most popular add-on.

There are about 30 to 40 membrane switch providers in Taiwan, most of them small and midsize businesses. The key players include CKT Tek Co. Ltd, In-Mould Technology Co. Ltd, MKS Corp., ShunOn and Win Industry Co. To broaden reach and deal with stiff price competition, suppliers offer related products such as rubber keypads, nameplates, touch panels, flexible PCBs and in-mold decoration by roller.

Makers in the island source PET and conductive ink from local partners or US and Japan. Ink deliveries from the last, however, could be affected by the recent earthquake.

Taiwan enterprises have set up factories in mainland China’s south and eastern areas, particularly Guangdong province, to be accessible to buyers. The Greater China region is the main market for low-end membrane switches targeted at mobile phones and portable electronic devices. Japan, meanwhile, absorbs the bulk of upscale variants typically employed in medical equipment.

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