Plastic injection button moulding

In addition, our company has established cooperative relationships with plastic raw material suppliers, printing manufacturers, etc. to ensure the supply of raw materials and printing quality. Through our rich experience and perfect supply chain, our company can provide customers with high-quality customized plastic injection button moulding products to meet their specific needs. At the same time, we have 10 years of professional foreign trade service experience, understand the foreign trade process, and better serve our customers. For plastic injection button moulding products, we can make corresponding plastic parts, which is mainly done through injection molds.

The molding process for plastic injection-molded buttons exemplifies the high demands for precision and aesthetics. Although small, buttons integrate structural design, precision molds, material science, and meticulous craftsmanship, placing extremely high demands on manufacturers' comprehensive capabilities.

The following is a detailed molding process for button injection molding, specifically highlighting the differences and key areas of focus compared to large-scale injection molding.

Plastic Injection Button Molding Process

Phase 1: Design & Material Selection

This is the foundation for determining the button's feel, appearance, and functionality.

Key Product Design Points:

Uniform wall thickness: Typically 1.2mm - 2.0mm. Uneven wall thickness can lead to shrinkage, warping, and internal stress.

Draft angle: Adequate draft angle (typically 0.5° - 1.5°) is required to facilitate ejection and prevent surface damage.

Preload travel and latch: The design should include sufficient travel space and a cushioning structure for button depressing, and a reliable latch for secure installation.

Sprue (Gate) Location: Must be located on a non-exterior surface or in a concealed location, typically on the bottom or side of the button. Never on the front of the button.

Material Selection:

ABS: The most commonly used material, offering excellent overall performance, easy dyeing, and a surface that can be electroplated or painted. It's used for most appliance buttons.

PC (Polycarbonate): High strength and transparency, suitable for buttons requiring high impact resistance or a transparent window.

PMMA (Acrylic): Extremely transparent and glossy, suitable for high-end light-guiding buttons.

TPE/TPU (Soft Rubber): Used for overmolded buttons or non-slip surfaces that provide a soft touch, typically using a secondary injection molding (overmolding) process.

POM (Polyoxymethylene): Excellent wear resistance and self-lubricating properties, suitable for buttons requiring long life and high-frequency operation (such as keyboard keys).

Phase Two: Mold Design & Manufacturing

Button molds are a hallmark of precision molds, and their machining accuracy directly impacts button quality.

High-Precision Cavity:

The cavity must be mirror-polished to achieve the highest possible finish (e.g., VDI grade A0-A1), ensuring a flawless, glossy button surface.

For matte, frosted (e.g., leather grain), CD grain, and other effects, etching (skinning) is required.

Miniaturization and Precision Machining:

Precision wire-cut and mirror-finish EDM processes are used to create tiny ribs, buckles, and text patterns.

Text and logos on buttons are typically engraved (concave) into the mold, resulting in a raised, wear-resistant finish on the molded product.

Hot Runner System:

A needle-valve hot nozzle is commonly used, which controls the timing of injection molding, ensuring a high-quality appearance and eliminating gate marks.

For multi-cavity molds, hot runners ensure consistent filling of each cavity and uniform size and color across all buttons.

Exhaust System:

Precise exhaust grooves (typically 0.015-0.02mm deep) must be created. Otherwise, trapped air can cause localized burning (yellowing, black spots) or incomplete filling of the button.

Ejector System:

Ejector pins must be extremely small and located in concealed locations (such as the inner wall of the button or under the ribs). No ejection marks on the front surface are permitted. Sleeve ejectors or gas-assisted ejection are sometimes used to avoid defects.

Stage 3: Injection Molding Process

The goal of process tuning is to achieve a product with perfect appearance, dimensional stability, and low internal stress.

Material Handling:

Thorough drying is essential! Materials such as ABS and PC must be dried at 80°C-100°C for 2-4 hours before injection molding to prevent silver streaks (material smear) and moisture.

Injection Molding Parameters:

High mold temperature: Using a higher mold temperature (e.g., 60°C-80°C for ABS) helps replicate the mold surface gloss, minimize weld marks, and reduce internal stress.

High-Speed, High-Pressure: High-speed injection is used to quickly fill the mold cavity with the melt, perfectly replicating the high-gloss or etched effects on the mold surface.

High Back Pressure: High back pressure is applied during the screw's backward rotation, ensuring more uniform plasticization and consistent color mixing, thus preventing color shifts.

Low Holding Pressure: A lower holding pressure and time are used. Because buttons are thin, excessive holding pressure can lead to excessive internal stress and even mold sticking.

Phase 4: Post-Processing & Quality Control

Post-Processing:

Gate: A worker or robot precisely trims the gate and smoothes it out, leaving no residue.

Secondary Processing: Some buttons may require UV coating (for wear resistance), electroplating (for a metallic finish), or silk-screen/laser engraving (for character printing).

Quality Inspection (Extremely Rigorous):

100% Appearance Inspection: Under specific lighting conditions, each button is inspected visually or using an automated visual inspection (AOI) system for minor defects such as material blemishes, black spots, scratches, shrinkage, air marks, and color unevenness. This is a necessary step in button production.

Dimensional Inspection: Key dimensions such as diameter, height, and latch dimensions are inspected using a 2D image measuring instrument or microscope.

Feel and Function Testing: Samples are tested for button feel, ensuring even pressure, smooth springback, and proper interaction with the tactile switches on the PCB.

Lifespan Testing: Batch samples are tested for button lifespan (e.g., tens of thousands to millions of presses) to ensure durability.

Environmental Testing: Materials are ensured to comply with environmental standards such as RoHS and REACH.

We are a plastic injection button moulding manufacturer, providing high-quality plastic injection button moulding manufacturing. As long as you want to customize/develop plastic injection button moulding products, you can find us. We have professional injection mold design and mature manufacturing technology, providing you with one-stop service, from product design-mold making-product production-product packaging-product transportation, we can help you in every link. As long as you come to us, we will provide you with the ultimate service and satisfy you in terms of product quality, production time, information dialogue, etc.

Plastic Injection Mould making

Plastic molding specifications

Mold design:

Transaction process:

Mold testing:

Product packaging

Factory

We are Custom Plastic Mold factory. Our factory is plastic injection mold maker. we has 17 years of experience in professional custom plastic mold and 10 years of foreign trade experience. We are custom Plastic Mold supplier. We can provide custom Plastic Mold service. Our factory can make the Injection molded plastic parts, and the quality of the products will satisfy you.

We have more than 50 high-end machines and hundreds of engineers and designers. We can provide one-stop service, from product design - mold making - product production - product packaging - transportation. We have a complete production chain. We can meet all your requirements.

Services we provide:

Professional custom mold service, Plastic mold design and manufacturing .plastic product production, product design, mold design, blow mold customization, rotational mold customization, die-casting mold customization. 3D printing services, CNC manufacturing services, product packaging, customized packaging, shipping services.

We always adhere to the principles of quality first and time first. While providing customers with the highest quality products, try to maximize the production efficiency and shorten production time. We are proud to tell every customer that our company has not lost any customer since its establishment.If there is a problem with the product, we will seek a solution actively and take responsibility to the end.

FAQ

Q1: Are you trading company or manufacturer ?

A: We are manufacturers.

Q2. When can I get the quotation?

A: We usually quote within 2 days after we get your inquiry.

If you are very urgent, please call us or tell us in your email so that we can quote for you first.

Q3. How long is the lead-time for mold?

A: It all depends on the products' size and complexity. Normally, the lead time is 25 days.

Q4. I have no 3D drawing, how should I start the new project?

A: You can supply us a molding sample, we will help you finish the 3D drawing design.

Q5. Before shipment, how to make sure the products quality?

A: If you don't come to our factory and also don't have the third party for inspection, we will be as your inspection worker.

We will supply you a video for production process detail include process report, products size structure and surface detail, packing detail and so on.

Q6. What is your payment terms?

A: Mold Payment: 40% deposit by T/T in advance, 30% second mold payment before sending out the first trial samples, 30% mold balance after you agree the final samples.

B:Production Payment: 50% deposit in advance, 50% before sending out the final goods.

Q7: How do you make our business long-term and good relationship?

A:1. We keep good quality and competitive price to ensure our customers benefit for best quality products.

2. We respect every customer as our friend and we sincerely do business and make friends with them, no matter where they come from.