Some Features of the Adhesive Sealant

The stability of the adhesive sealant

The stability adhesive emulsion is related to color fastness. Emulsion particles should be controlled in the 0.2μm, and its particle size distribution should be uniform, and there are not both the big particles and small particles, or the friction fastness will be reduced, and the method to determine the quality of adhesive sealant is to observe the appearance of the emulsion, and the particles in the white emulsion illustrate are larger, which are at least 5 μm or more, the emulsion with the described yellow particles is very uneven, generally the particles are at least more than 2μm, and the emulsion with blue particles is around 1μm, and the ideal adhesive should be blue translucent emulsion, which is not milky, indicating the size of the particles are in the 0.2-1μm, and the particle size distribution range is narrow.



Improve the adhesive rubbing fastness

The rubbing fastness of pigment printing is the most troublesome. In the used printing paste, some factories add organic silicon, but the effect was not significant. Some people think that this is caused by the uneven coating particle size, it was also considered to be caused by the adhesive, use polyurethane adhesive rubbing fastness of the same coating can be qualified and unqualified acrylate adhesive, and the use of different matching adhesive its situation is different. Of course, the coating particles bring some affects, when the particle diameter is large, and the crystal form and particle size distribution uneven course rubbing fastness will reduce, but under the same circumstances in the coatings, Heat Sink Paste play a decisive role. The main factors affecting rubbing fastness is the coefficient of friction of the coating, and the rich than a low content of the smoothness of the film to its friction with high fastness, and the fastness of polyacrylate adhesive with the high content of the soft monomer is poorer than the one with less content.

Three ways to solve the rubbing fastness

The aids increasing friction fastness are added in the paste, which is a silicone elastomer, or an oxidized polyethylene emulsion, the amount is greater than 5%, less ineffective, its purpose is added the substance with the smoothing effect to the film. It can be used together with the polyurethane adhesive to improve the performance of the film by the polyurethane. The new copolymer which is made of acrylate and silicone monomer is the existing product.

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Flame retardant RTV silicone, yellow glue, white glue thermal conductive silicone (silicon) , thermal silicon grease (thermal paste), SMT placement glue, the screw glue, LED module potting glue, circuit board 3 –resisting glue, fast drying, two-component sealing glue, epoxy AB glue, lead-free solder paste, lead-free reducing slag, lead-free disposable flux and other electronic industrial adhesives and dispensing equipments.

This article is come from:http://www.metal-tinbox.com/index.php/some-features-of-the-adhesive-sealant.htm

The Impact Factors of Electronic Adhesive

The electronic glue viscosity is an important performance indicator, such as the high demand of the bare chip (COB) technology to the glue cured heap and potting glue long plastic rheology requirements are the Heat Sink Paste degree requirements.



Generally, the electronic adhesive with the higher viscosity has relativly large molecular mass with good heat resistance and the initial adhesion strength is high. The products with high viscosity and low solid help to reduce the cost of product. However, in practical applications, the high viscosity of the electronic adhesive will often lead to mutual dissolution of the components in the production process more difficult, so that the rheology of the glue is poor.

Factors affecting the viscosity of the electronic glue First, it is convenient for filler in regulating electronic adhesive degree. After choosing the filler according to the performance need, you can adjust the viscosity of the adhesive through the appropriate choice of particle size and mass fraction, to meet the construction process. Second, the system viscosity obtained from the different types of the prepolymer is different, and in the precondition of satisfing the basic performance, we can make the appropriate choice of the prepolymer based on the needs of the electronic adhesive degrees with the thermal paste substitute, and by adjusting the mass fraction of the prepolymer, to meet the viscosity of the system and optimum performance requirements. Since the adjustment of the system viscosity is not very clear wehn the prepolymer mass fraction is more than 50%, therefore, in order to reduce costs, the mass fraction of the prepolymer generally will not exceed 50%.

Third, a coupling agent has the amphiphilic structure, which can improve the dispersion state of the inorganic powder in the matrix, in order to improve the rheology of the system, and an amount of 2% of the coupling agent is more appropriate. Fourth, stirring allows system mixing, uniformity of performance, and we should choose the appropriate stirring rate and mixing time, in order to meet the desired physical properties. Fifth, adhesive curing process is actually the process of e-adhesive degree change, and the mass fraction of the curing agent affects adhesive gel point balance from the system to the time (valid), so the amount of curing agent should be appropriate. We should keep these points in mind to make the better research in the electronic glue to take more shares in the market.

Thanks to the seven-year arduous pioneering, www.zscnr.com has marched into the stage of rapid development. Confronting to the domestic competition of adhesive, the company takes slow and steady efforts to catch up and now it has created a well-known brand among the domestic adhesive industry. The whole company will tenaciously strive to enter into the top 100 of the domestic adhesive industry.

This article is come from: http://www.soundspeakers.cn/index.php/the-impact-factors-of-electronic-adhesive.htm

The Development Trend of Pigment Printing Binding Agent

Requirements on pigment printing adhesive

In order to solve the core issues of the feel, color fastness and environment of pigment printing, the environmentally friendly printing binder is synthesized. Heat Sink Paste must meet the following requirements: the formed film is colorless and transparent and it will not become yellow after heating. The nature of the film is sturdy with good elasticity, adhesion, washable and dry cleaning and resistant to the sun and aging; film-forming is soft, feel good and not tacky after the treatment of fabric. The color fastness of printing fabric is not less than the dye printing standards.



The important role of heat sink paste

Pigment printing process is simple, saves energy, with chromatography and no wastewater discharge. Mixed colors and spline are convenient, printing outline is clear, genuine rate is high, reproducibility is strong and general light fastness is good. In recent years, many new materials can be used in pigment printing process, especially with the development of synthetic fiber and blended fabric, the superiority and the importance of the pigment printing are more prominent. Today's global pigment printing takes the average share of the total printing market share of 45% and it takes the largest proportion of all printing. Among them, ratio of upholstery fabrics is 38%. However, pigment printing printed fabric has low rubbing fastness and it will release odor in the operating environment. Although countries in the world have spared no effort to improve and develop new coatings for many years and make great progress in their supporting new additives, such as adhesive sealant, it is difficult to get the overall balance in feel, fastness, seepage, environmental protection and other aspects.

Development and status quo of the pigment printing binder

In the 1950s, the rapid rise in petrochemical and polymer science has spawned a wide variety of synthetic polymer binder. As the shortcomings of complex traditional dyeing process, various rejects, high cost and long processing cycle, foreign countries put forward pigment dyeing and printing. From the direction of development to improve the fastness, improve feel, and reduce energy consumption, foreign adhesives mainly have gone through four stages: the first generation of adhesives is not cross-linked polymer film-forming substances. The second generation was added -CN,-OH,-NH2,-COOH reactive group; the third generation was added self-crosslinking monomer in the binder component in order to improve fastness, reduce curing temperature and shorten the baking time. The fourth-generation printing binder - low-crosslinking binder appeared soon. The crosslinking molecular structure has a strong reactive group, and can react with the hydroxyl group or an amino group at 100 degrees Celsius and can improve the deposition, but also greatly save energy. China also made a lot of research in improving the adhesive application performance and exploring new synthesis process.

www.zscnr.com

Thanks to the seven-year arduous pioneering, Conor has marched into the stage of rapid development. Confronting to the domestic competition of adhesive, the company takes slow and steady efforts to catch up and now it has created a well-known brand among the domestic adhesive industry.

This article is come from: http://www.zscnr.com/news/12.htm

Green Revolution of Packaging - DN-90 Quick-Drying Starch Adhesive

Confusing SMT Adhesives Market

With the development of market economy, China's small and medium-sized cardboard box factory is everywhere, due to the relevant departments for a long time is not clearly sodium silicate binder materials, cannot be used on the domestic packaging carton, the carton standard adhesives do not clearly defined. Currently, it is popular on the market a "the carton treasure", "starch glue, its prices are less than ideal performance, cause confusion to the market, allowing users to select glue caused psychological barriers, for many small carton factory crude the easy way, so the use is more than 100 years of traditional products sodium silicate carton adhesive material, not knowing that there are many drawbacks to do with sodium silicate binder, experts called to reiterate carton production should be eliminated sodium silicate, and requires a Starch smt adhesive.

Drawbacks of the Sodium Silicate Adhesive

Sodium silicate is an aqueous solution of sodium silicate, is a strong base, weak acid salt, showed a strong alkaline, the free base is 6% to 7%. The sodium silicate is able to penetrate the carton surface, corrosion contents, does not meet the packaging requirements of food hygiene, and foreign trade. In a humid environment, the sodium silicate absorbent deliquescence, loss of adhesion, carton paper softened and deliquescence efflorescence, affecting printed effect help cartons appearance. As we all know, the use of sodium silicate, as an adhesive material cartons is hygroscopic, toxic, endangering human health and ecological environment seriously affect the quality of packaging products and merchandise sales, our packaging solved cut key issues, the paper and packaging industry tilted the period of waiting for a new generation of adhesives speedy advent! Developed capitalist countries in the 1950s are out of the sodium silicate in 1984, China began to limit and prohibit the use of sodium silicate in the export and food packaging.

New Multi-functional Starch Adhesive

In May 1991, the State Economic and Trade Commission, Bureau of Technical Supervision, the Ministry of Foreign Trade again noticed "disabled since 1992 all packaging plant sodium silicate adhesive material". But what suffers is that unable to find a substitute. And some foreigners even ridiculed: Chinese have the first class products, but the packaging is not inflow, such as the Heat Sink Paste. Especially in the current paper packaging industry trends, all require the use of green packaging, so as to protect the environment, and in particular the accession to the WTO will be higher on the packaging requirements of environmental protection. There should be a new generation of patented products in order to meet the requirements of the times and the binder demand and trends, so the DN-90 series multi-functional starch adhesives came into being, it is a new type of solid powder adhesive material as the main raw material.

This article is come from: http://www.power-supplier.info/digital-screen/green-revolution-of-packaging-dn-90-quick-drying-starch-adhesive.htm

Thermal Heat Sink Paste Information

Features of Heat Sink Paste

Heat sink paste is made of Polysiloxane and the high thermal conductive filler, featuring non-toxic, tasteless and non-corrosive. Its chemical and physical properties are stable with excellent electrical insulation and excellent thermal conductivity. Heat sink paste like smt adhesive is resistant to high and low temperature with the temperature range of -600℃ to 250℃. After long-term working it will not be air-dried, hardening or melting. It is mainly used to fill the gap between the heating body and heat sink, improving the cooling effect.

Detailed Information on Heat Sink Paste

Heat sink paste is often called thermal grease, but actually should be named silicon paste for it is made of silicone oil. The silicone oil is a kind of polysiloxane. From a structural point of view, heat sink paste is a long chain consisting of a lot of silane with thousand to millions of molecular. They feature excellent heat resistance, electrical insulation, thermal conductivity, damping, and its viscosity is not sensitive to temperature. Their chemical property is stable, less volatile, non-toxic and tasteless. The silicon paste filler is the very fine powder through grinding with zinc oxide / alumina / boron nitride / silicon carbide / aluminum as their ingredients. Silicone oil ensures a certain amount of mobility, and fillers help fill the tiny gap between the CPU and heat sink to ensure thermal conductivity. Due to low sensitivity of silicone oil to temperature sensitivity, it won’t become thick under low temperature or become diluted under high temperature, and it features non-volatile, so available to be used for a long time. How to transfer heat between heat the heat sink and CPU? Well it mainly relies on conducting method – directly connecting the heat sink paste and CPU. The purpose of using the thermal grease is to fill the gap between them, making the connection perfect. If the grease is used in excess, there would form a grease layer between the CPU and heat sink, so the cooling path turns out to be CPU --- grease --- heat sink.

Notes When Using Heat Sink Paste
Some high-grade thermal grease uses the silver powder or aluminum powder as its filler, for these metals have high thermal conductivity. But metal particles have big sizes with poor filling effects, so the performance of heat sink paste cannot be improved greatly. Even though grease features electric conductivity, short circuit would lead if not use appropriately.

This article is come from: http://cell.battery-products.com/heat-sink-paste/thermal-heat-sink-paste-information.htm