What differences between PC and TPU of LGF Raw Material?

Do you know what LGF is made of? One of the most important raw materials of LGF products is the medium material of light transmission, including TPU, PC and PMMA. The light emitting effect of different materials is greatly different, due to their different physical characteristics and thickness. PC (PC-Specification.pdf) is the most commonly used as light medium for light guide film, and its light emitting effect is relatively the best one. TPU is also used as light guide film, but very rarely. This is caused by the differences between PC and TPU as follows:

ItemPC materialTPU material
HardnessAround HR140HR70-80
ColorTransparentTransparent
Price/2-3 times compared with PC
Processing dot modePrinting, molding, rollingPrinting, radium carving
Influence on hand sensation after assembling keysThe click feeling of the key decrease by 5~10%The click feeling of the key decrease by 2~6%
Transmittance>89%78%
Brightnesshigher(better)lower(worse)
Thickness of material0.1mm, 0.125mm, 0.175mm, 0.25mm, 0.38mm, 0.5mm0.1mm, 0.15mm
Resistance to chemical corrosionThe corrosion resistance is worse, but because the light guide film is a built-in component, it doesn’t come into contact with as many chemicals, so this factor is not considered as muchCorrosion resistance is better, so it is more suitable for external parts, external parts contact with chemical reagents will be more, such as watchband
Using impactPC will not have issue of yellowTPU will be became yellow after 2 years used, and it affects brightness and transmittance
Posted in LGF dome array, metal dome related | Tagged , | Comments Off on What differences between PC and TPU of LGF Raw Material?

What advantages of LGF (light guide film)?

When says light, it’s natural to think of lights (LED), so how can we use as few lights (LED) as possible to produce the best light effect?

LGF (light guide film), it has the characteristics of ultra-thin, uniform light, color changes and so on. It is a product that converts the point light source of LED into a surface light source.

The mainly advantages of LGF (light guide film) as following:

1. Good luminous effect, uniform brightness, high light intensity.

2. Light, soft, thin thickness. In the usage of mobile phones, different from the light guide plate takes up a large space.

3. Save LED quantity, save power consumption, save cost.

4. Simple structure, does not affect the overall product design (does not affect the click sound of metal dome) and feel good.

Light-guide-film-dome-array-6
Light-guide-film-dome-array-10
Posted in LGF dome array, metal dome related, Metal Domes | Tagged , | Comments Off on What advantages of LGF (light guide film)?

Happy Moon-cake Day

Today is the 15th day of August (according to the Lunar Calendar) is the Moon Cake Day, one the most important traditional festival in China (Others are Dragon Boat Festival and Spring Festival). And the official name is Mid-Autumn Festival, because it is happened in the middle of Autumn. Family member will come back from their working city to their hometown, to enjoy happy & warm time with their families, and of course will eat the moon-cake and drink the tea.

In order to thank all employees for their dedicated working and efforts, Best Technology prepared handle-made Mid-Autumn moon cakes to express our best wishes and thanks to our staffs.

All staffs from Best Technology received the delicious Moon cakes and everyone is permeated with warm and harmonious festive atmosphere. As a member of Best Tech, I felt full of happiness when received the cakes.

The moon cake not only represents the Mid-Autumn greetings and blessing to employees, but also shows the loving care from management for us. It not only brought laughter, also brought full of touching and motivation to everyone. I believe that in the future, we will cheer up, make persistent efforts, and create a more brilliant tomorrow for the company!

Best Tech is a big family and everyone is a member of this family that we love and help each other.

Since the establishment of company in 2006, Best Technology always pay highly attention to the healthy & happy life of our staffs, in every traditional festival in China, we will receive different beautiful gifts and best wishes.

Best Tech is a big family and everyone is a member of this family that we love and help each other.

Since the establishment of company in 2006, Best Technology always pay highly attention to the healthy & happy life of our staffs, in every traditional festival in China, we will receive different beautiful gifts and best wishes.

At the same time, all the people in Best Technology wish our customers a merry Mid-Autumn Festival, bliss and happiness, wish you a perfect life just like the round moon in Moon-cake Day!!

Also, Best will close for Moon-cake Day from Sept 10-12th, and resume to office on Sept 13th, if you have any inquiry, please contact us.

Posted in Chinese Culture | Tagged , | Comments Off on Happy Moon-cake Day

The Quality Inspection of the Metal Dome

Metal dome is an important part used for membrane switch, micro switch, printed circuit boards and so on. It plays a role of conducting the electricity. Thus, it is essential to ensure the quality of the domes.

Metal Domes

But what should be paid heed to when the IQC department detects the quality of the metal domes? Here are five points.

  • Appearance: to check whether there is dust, oil stain, or spot on it.
  • Burr: it can be checked by using the A4 paper to rub the edge of the dome.
  • Force test: to test the force by force tester, and the normal range of the force is ±30%.
  • Contact resistance test: the contact resistance of the stainless steel metal dome is less than 10 Ohm, while the contact resistance of the metal dome plated with nickel, silver and gold is less than 1 Ohm.
  • Lifetime: to test whether the snap dome is up to the mustard by the lifetime tester.

To sum up, in order to guarantee the quality of the metal dome, it is necessary to pay attention to these five points, including appearance, burr, force test, contact resistance test and lifetime.

So, this is the end of this article. At Best Technology, with more than 15 years of experience, we are fully equipped to handle your metal dome or dome array manufacturing requirements. In case if you have any questions, please feel free to contact us via email at sales@metal-domes.com or call us on +86-755 2909-1601/1602/1603.

Posted in metal dome related, Metal Domes | Tagged , | Comments Off on The Quality Inspection of the Metal Dome

How to Produce the 3M Adhesive Dome Array?

Namely, 3M adhesive dome array uses the 3M adhesive instead of the common adhesive used in the dome array. 3M adhesive is a little bit thick. Some of them even have the ability of high temperature resistance. So, it should be produced by opening a mold, while cannot be processed by laser. The processing steps are as follows.

The process of manufacturing the 3M adhesive dome array:

  • Cover one side of the double-side non-adhesive PET with the 3M adhesive.
  • Punch the dome holes.
  • Cover with Mylar.
  • Punch the outline.
Single and Double Layer Dome Array

And it is noteworthy that although the material used is 3M adhesive, whose viscosity is better, it is indistinguishable from appearance compared with the dome array using common adhesive on account of its transparent color.

Moreover, the model of 3M adhesive dome array can be customized depending on client’s request. But on account of the difference of the specific type and minimum order quantity, it does not necessarily fit with non-adhesive PET, hence circumstances after cases.

At Best Technology, with more than 15 years of experience, we are fully equipped to handle your metal dome or dome array manufacturing requirements. In case if you have any questions, please feel free to contact us via email at sales@metal-domes.com or call us on +86-755 2909-1601/1602/1603.

Posted in metal dome array, metal dome related | Comments Off on How to Produce the 3M Adhesive Dome Array?

The Structure of the Metal Dome Array

Metal dome array, generally, is double layer structure, but there is also single-layered.

For the double layer dome array, there are two layers, including Mylar, spacer and metal dome. The uppermost is the Mylar with the thickness of 0.05 mm, which is very thin. Then the thickness of the spacer is 0.075 mm with the tolerance of ±0.01 mm. And the underneath is the metal dome.

For this structure, the metal domes are connected by ventilation slots in the fabricated dome array. In this way, when you press the metal dome to conduct, the air can run along the ventilation slots. The purpose of it is to have a good click feeling and conduction ability.

Structure of Double Layer Dome Array

For the single layer dome array, the uppermost is Mylar. And its thickness is generally 0.05 mm or 0.075 mm. Besides, some of the Mylars in the single layer dome array will not have the ventilation slots, while some will make a small hole on it according to the customer’s requirements.

Structure of Single Layer Dome Array

Either the single layer dome array or the double layer dome array, there are release paper and protective film under the metal dome, aiming to protect the dome array. When the dome array has been torn down, the release paper and protective film will be the waste.

Therefore, the effect caused by the specifications of the release paper and protective film is not particularly large.

So, this is all about the introduction to the structure of the dome array. And if you have any questions about the dome or the dome array, you are welcome to contact us.

Posted in metal dome array, metal dome related, Metal Domes | Comments Off on The Structure of the Metal Dome Array

What are the Main Applications of Different Metal Domes?

We all know that there are four types of tactile metal domes, including four-leg, circle, triangle and oblong. And these domes play different roles in various fields, even some of them can be substitute for each other. However, they virtually have their main application fields, which is more or less an unwritten rule.

Four-leg Metal Dome

In terms of structure, the height of four-leg domes is often higher than that of three other domes, hence the click feeling is also better. And four-leg domes are now mainly concentrated on the relatively large ones ranging from 5 mm to 20 mm, which is one of its advantages. With greater click feeling and longer life, this kind of snap dome is also called membrane switch dome, for which is most commonly used in membrane switch.

Four-leg Dome Sheet

Circle Metal Dome

Contrary to four-leg snap dome, circle metal dome, or round dome, focuses on the relatively small ones like 2.5 mm-5 mm. Thus, when there is only a small space on the PCB, the circle snap dome is the best option. And because most of the domes used in the phone are round dome, it is also named mobile phone dome.

Round Domes on FPC

Triangle Metal Dome

The advantage of triangle snap dome is that it can get the maximum force under the same diameter in comparison with other domes, which means it needs to be pressed hard to be conductive, so as to avoid misoperation especially in industrial control. Therefore, triangle dome metal is extremely suitable for industrial controls, like control panel.

Triangle Domes on PCB

Oblong Metal Dome

Oblong dome is seldom used. Because of its shape, oblong dome metal, also called rectangle snap dome, can be used in a long and narrow space compared with other three domes. And it is mainly used to be mounted on printed circuit boards, and other products such as membranes, panels, and so forth.

In a word, although it is not stipulated that only one of these snap domes can be used in a field, which indicates that they may be alternatives for each other in accordance with the specific uses and requirements, they generally still have their main application fields. And we, Best Technology, are an experienced electronic company so that if you would like to know more about metal domes or snap domes, you are welcome to contact us.

Posted in Circle metal dome, Four leg metal dome, Membrane Switches, metal dome array, metal dome related, Metal Domes, Oblong Metal Dome, Triangle metal dome | Tagged | Comments Off on What are the Main Applications of Different Metal Domes?

How to assemble metal dome on PET adhesive sheet?

Normally we have three method to assemble metal dome on PET adhesive sheet. Please check details below:

  1. Assembly jig: this is the assembly method we use often currently. According to the drawing of PET adhesive sheet (dome array) to make a fixture, material is aluminum plate. The dome holes on plate is base on shape of different metal domes and qty. Like below photos, place with 8.4mm four legs metal dome with qty 69 keys.
Assembly jig (plate)
Place PET adhesive (dome array) on assembly Jig (plate)
Stick metal dome on PET adhesive
  • Through the assembly of tube fixture, this method has small tolerance and fast speed, but the cost is relatively high, suitable for relatively large quantity of production. Like below photos.
Collect metal domes in tube
Dome switch Tube in assembly machine
  • Place snap dome or metal dome on PET adhesive by manual. Usually if the customer only requires few prototype and samples, and does not want to pay the fixture fee, we will manually place metal domes of the sample. The disadvantage of this fitting method is that the fitting tolerance is relatively large, and some may tilt more severely.
Place metal dome on PET adhesive by manual

This video you will know more clearly.

If you still have any question after read, please feel free to contact us, we are here always and would solve your issue and provide our help to you.

Posted in Business, metal dome array, Metal Dome Assembly, metal dome related | Comments Off on How to assemble metal dome on PET adhesive sheet?

How to measure the diameter of triangle metal dome?

Are you wondering how to measure the diameter of triangle metal dome? If you are interesting, let me introduce it brifely.

various triangle metal dome

Method one: We know there are three vertices on each sideline of traingle dome, so we can draw a circle along the three vertices and emasure the diameter of circle to get a result, which is diameter of triangle metal dome as well.

method two to measure the diameter of triangle metal

Method two: Measure the distance from one vertice to the oppsite side to get a result and take an integer, this integer is diameter of triangle dome. For example, if you test like this and get a result as 6.51mm, then the diameter of triangle dome is 7mm.

draw a circle to measure the diameter of triangle dome

Method three: If the triangle metal dome with legs, we can simple measure the distance between two legs, and this distance is also the diameter of triangle metal dome.

metal dome

Best Technology, as the top 5 metal dome & dome array manufacturer in China, we have more than 15 years experience in snap dome, metal dome sheet and tactile membrane switch industrial, our metal dome is equivalent with Snaptron & Nicomatic metal dome,we can always provide you the best solution for your dome switch project. If you have any doubt or inquiry about the snap dome please kindly call us or email us at any time.

Posted in Business, FAQ, Inside News, metal dome array, Triangle metal dome | Comments Off on How to measure the diameter of triangle metal dome?

Do you know the differences of tooling types that making metal dome?

Normally we will use two types punching toolings to make metal dome: high speed tooling and low speed tooling, see below photos. Is there any difference in metal dome they produce? The answer is ” Yes”, there are many differences, please see below for more details.

  1. The stability of quality of dome switch is better with high speed tooling.
  2. The stamping speed is faster with high speed tooling, so lead time will be shorter. Normally 3-5 days for high speed tooling, 7-10 days for low speed tooling. Of course, we also need to depend on the production schedule and order quantity at that time.
  3. The life time is higher with high speed tooling. For example, for same diameter dome 12.2mm, 350g, the life times could be more than one million with high speed tooling, but only around 0.1 million times with low speed tooling.
  4. The high-speed molding line is on the outside and the low-speed molding line is on the inside.
  5. The burr is smaller (around 0.3mm) with high speed tooling than low speed tooling (above 0.5mm).
  6. The cost of high speed tooling is around 10,000 USD-20,000USD, but the cost of low speed tooling is around 1,000 USD-5,000 USD
  7. The price of metal dome with high speed tooling is higher than low speed tooling, because of better quality.

In a word, when we choose a metal dome, we should not only pursue the price, but also look at other aspects, such as production technology, quality, delivery time and so on.

If you want to know more about metal dome, please don’t hesitate to contact us, Best Technology. We are always here, waiting for you.

High speed tooling
Low speed tooling

Posted in Circle metal dome, metal dome array, Metal Domes | Comments Off on Do you know the differences of tooling types that making metal dome?