Introduction
Why do we need plasticizers?
Mechanism of action of plasticizers
Properties of plasticizers
Classification of plasticizers
Selection of plasticizers
Effect of plasticizer on permeability of film.
Effect of plasticizer on mechanical properties of film.
Effect on residual internal stress.
Effect of plasticizers on release rates of drug.
Texture of plasticized films.
Limitations.
Conclusion.
Study of characteristics of partial replacement of phenol by coconut shell fl...eSAT Journals
Abstract Phenol formaldehyde (PF) resins are usually synthetic polymer resins, based on the condensation reaction of formaldehyde with phenol. Phenol being a vital component is rarely available now and the cost of which influences the cost of the adhesive. An alternative, cheaper source of Phenol would be of great interest to all users of PF resin. World wide shortage, increase in price and future supplies of phenol for the wood based panel industries have renewed the interest in finding partial or full substitutes based on non-petroleum resources for synthetic resin adhesives. Since wood materials like flours of sal, teak, coconut etc. contain ligno cellulosic materials; can be used for the partial replacement of phenol in phenolic adhesives. In the present investigation, an attempt has been made to develop and study the characteristics of a new resin synthesized by using coconut shell flour as a partial replacement for phenol in a phenol formaldehyde resin. Coconut Shell Flour (CSF) being comparatively cheaper, indigenously available, is renewable phenolic raw material and is found to be effective for partial replacement. Resin adhesive prepared from CSF of particle size -150 +250 was found to be suitable. The effect of partial replacement on properties of the resulting resin viz. tensile strength, effect of pH on polymerization time, morphology using Wide angle X-ray diffraction, SEM images of the surface morphology of pure phenol formaldehyde resin and CSF embedded resin material were investigated by scanning electron microscopy (SEM) at 10 kV with a JEOL (Japan) JSM-840A scanning electron microscope. Investigations revealed that 40-50% of phenol can be replaced by using CSF. Keywords: Coconut Shell Flour CSF, Phenolic, Adhesive, Partial replacement, Tensile strength, Wide angle XRD.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Introduction
Why do we need plasticizers?
Mechanism of action of plasticizers
Properties of plasticizers
Classification of plasticizers
Selection of plasticizers
Effect of plasticizer on permeability of film.
Effect of plasticizer on mechanical properties of film.
Effect on residual internal stress.
Effect of plasticizers on release rates of drug.
Texture of plasticized films.
Limitations.
Conclusion.
Study of characteristics of partial replacement of phenol by coconut shell fl...eSAT Journals
Abstract Phenol formaldehyde (PF) resins are usually synthetic polymer resins, based on the condensation reaction of formaldehyde with phenol. Phenol being a vital component is rarely available now and the cost of which influences the cost of the adhesive. An alternative, cheaper source of Phenol would be of great interest to all users of PF resin. World wide shortage, increase in price and future supplies of phenol for the wood based panel industries have renewed the interest in finding partial or full substitutes based on non-petroleum resources for synthetic resin adhesives. Since wood materials like flours of sal, teak, coconut etc. contain ligno cellulosic materials; can be used for the partial replacement of phenol in phenolic adhesives. In the present investigation, an attempt has been made to develop and study the characteristics of a new resin synthesized by using coconut shell flour as a partial replacement for phenol in a phenol formaldehyde resin. Coconut Shell Flour (CSF) being comparatively cheaper, indigenously available, is renewable phenolic raw material and is found to be effective for partial replacement. Resin adhesive prepared from CSF of particle size -150 +250 was found to be suitable. The effect of partial replacement on properties of the resulting resin viz. tensile strength, effect of pH on polymerization time, morphology using Wide angle X-ray diffraction, SEM images of the surface morphology of pure phenol formaldehyde resin and CSF embedded resin material were investigated by scanning electron microscopy (SEM) at 10 kV with a JEOL (Japan) JSM-840A scanning electron microscope. Investigations revealed that 40-50% of phenol can be replaced by using CSF. Keywords: Coconut Shell Flour CSF, Phenolic, Adhesive, Partial replacement, Tensile strength, Wide angle XRD.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
MECHANICAL AND PHYSICAL PROPERTIES OF GREEN PARTICAL BOARD PRODUCE FROM CORNC...prawitjitiyakron
This research studied the potential of renewable material, corncob, as a composite with
starch binder to produce green particleboard. The starch was used as a binder in stead of
binder from formaldehyde. The corncob and starch binder composite was prepared using
compression molding at ratio between the composite was 9:1, 8:2, 7:3 and 6:4 respectively.
The increase of concentration of starch binder increased density and tensile strength of
composite. The result of water absorption of composite decreased with higher binder
content. As a natural material, it was shown that the mechanical performance of corncob and
starch binder composite could be tailored to reproduce the behavior of green particle boards
Spinning process
What is gel spinning
Gel spinning process
what are the factors affecting gel spinning
Gel spinning process polyethylene
Structure and Properties of Gel spun fiber
Applications
A powerpoint presentation focusing mainly on the material aspects of composite resins. The second part of this presentation deals with the clinical aspects
Evaluation of the physical & mechanical properties of high drug load formulations (Metformin, APAP, and Aspirin) - Wet Granulation vs. Foam technique
Indian Dental Academy: will be one of the most relevant and exciting
training center with best faculty and flexible training programs
for dental professionals who wish to advance in their dental
practice,Offers certified courses in Dental
implants,Orthodontics,Endodontics,Cosmetic Dentistry, Prosthetic
Dentistry, Periodontics and General Dentistry.
Short Description related to the rubber filler properties and Rubber filler types ( Reinforcing fillers, Semi- reinforcing fillers and Non-reinforcing fillers). e.g.:- Carbon Black, Silica, Calcium Carbonate, Clay and Miscellaneous Fillers
Composite is a tooth coloured filling material widely used in restorative dentistry, it's actual name is 'Particulate reinforced polymer matrix composite resin.'
MECHANICAL AND PHYSICAL PROPERTIES OF GREEN PARTICAL BOARD PRODUCE FROM CORNC...prawitjitiyakron
This research studied the potential of renewable material, corncob, as a composite with
starch binder to produce green particleboard. The starch was used as a binder in stead of
binder from formaldehyde. The corncob and starch binder composite was prepared using
compression molding at ratio between the composite was 9:1, 8:2, 7:3 and 6:4 respectively.
The increase of concentration of starch binder increased density and tensile strength of
composite. The result of water absorption of composite decreased with higher binder
content. As a natural material, it was shown that the mechanical performance of corncob and
starch binder composite could be tailored to reproduce the behavior of green particle boards
Spinning process
What is gel spinning
Gel spinning process
what are the factors affecting gel spinning
Gel spinning process polyethylene
Structure and Properties of Gel spun fiber
Applications
A powerpoint presentation focusing mainly on the material aspects of composite resins. The second part of this presentation deals with the clinical aspects
Evaluation of the physical & mechanical properties of high drug load formulations (Metformin, APAP, and Aspirin) - Wet Granulation vs. Foam technique
Indian Dental Academy: will be one of the most relevant and exciting
training center with best faculty and flexible training programs
for dental professionals who wish to advance in their dental
practice,Offers certified courses in Dental
implants,Orthodontics,Endodontics,Cosmetic Dentistry, Prosthetic
Dentistry, Periodontics and General Dentistry.
Short Description related to the rubber filler properties and Rubber filler types ( Reinforcing fillers, Semi- reinforcing fillers and Non-reinforcing fillers). e.g.:- Carbon Black, Silica, Calcium Carbonate, Clay and Miscellaneous Fillers
Composite is a tooth coloured filling material widely used in restorative dentistry, it's actual name is 'Particulate reinforced polymer matrix composite resin.'
characterization of ceramic green body for specific objectivesabebewolelaw6
characterization is mandatory for ceramic green bodies in order to identify there relative density, pore size and pore distribution, there morphology and thier microstructure as well
Detailed description of types of plasticizers, mode of selection, types of effects produced on polymers and optimization of plasticizers in aqueous/organic coating based systems.
Ekeeda Provides Online Engineering Subjects Video Lectures and Tutorials of Mumbai University (MU) Courses. Visit us: https://ekeeda.com/streamdetails/University/Mumbai-University
Ekeeda Provides Online Engineering Subjects Video Lectures and Tutorials of Mumbai University (MU) Courses. Visit us: https://ekeeda.com/streamdetails/University/Mumbai-University
DESIGN OF OPEN GRADED FRICTION COURSE MIX USING POLYMER MODIFIED BITUMEN(LDPE)ARUN KANNA
Generation of plastics has increased significantly. Utilization of all types of plastics is unavoidable and it will produce non-biodegradable waste materials. The waste plastics are harmful to the environment if it is not disposed properly. It is very useful in the design and development of high quality flexible road pavement. So, adding the waste plastics as additives in the mix design of the pavement was expected to give good performance when comparing with conventional mix. In this project, advantages and development of modified bitumen is to be studied. The dosage of LDPE modified binder has taken as 6%, 8% &10% in the Open Graded Frictional Course (OGFC) mix design by wet process. The result shows the performance of OGFC mix using PMB.
Encryption in Microsoft 365 - ExpertsLive Netherlands 2024Albert Hoitingh
In this session I delve into the encryption technology used in Microsoft 365 and Microsoft Purview. Including the concepts of Customer Key and Double Key Encryption.
Elevating Tactical DDD Patterns Through Object CalisthenicsDorra BARTAGUIZ
After immersing yourself in the blue book and its red counterpart, attending DDD-focused conferences, and applying tactical patterns, you're left with a crucial question: How do I ensure my design is effective? Tactical patterns within Domain-Driven Design (DDD) serve as guiding principles for creating clear and manageable domain models. However, achieving success with these patterns requires additional guidance. Interestingly, we've observed that a set of constraints initially designed for training purposes remarkably aligns with effective pattern implementation, offering a more ‘mechanical’ approach. Let's explore together how Object Calisthenics can elevate the design of your tactical DDD patterns, offering concrete help for those venturing into DDD for the first time!
A tale of scale & speed: How the US Navy is enabling software delivery from l...sonjaschweigert1
Rapid and secure feature delivery is a goal across every application team and every branch of the DoD. The Navy’s DevSecOps platform, Party Barge, has achieved:
- Reduction in onboarding time from 5 weeks to 1 day
- Improved developer experience and productivity through actionable findings and reduction of false positives
- Maintenance of superior security standards and inherent policy enforcement with Authorization to Operate (ATO)
Development teams can ship efficiently and ensure applications are cyber ready for Navy Authorizing Officials (AOs). In this webinar, Sigma Defense and Anchore will give attendees a look behind the scenes and demo secure pipeline automation and security artifacts that speed up application ATO and time to production.
We will cover:
- How to remove silos in DevSecOps
- How to build efficient development pipeline roles and component templates
- How to deliver security artifacts that matter for ATO’s (SBOMs, vulnerability reports, and policy evidence)
- How to streamline operations with automated policy checks on container images
Securing your Kubernetes cluster_ a step-by-step guide to success !KatiaHIMEUR1
Today, after several years of existence, an extremely active community and an ultra-dynamic ecosystem, Kubernetes has established itself as the de facto standard in container orchestration. Thanks to a wide range of managed services, it has never been so easy to set up a ready-to-use Kubernetes cluster.
However, this ease of use means that the subject of security in Kubernetes is often left for later, or even neglected. This exposes companies to significant risks.
In this talk, I'll show you step-by-step how to secure your Kubernetes cluster for greater peace of mind and reliability.
Builder.ai Founder Sachin Dev Duggal's Strategic Approach to Create an Innova...Ramesh Iyer
In today's fast-changing business world, Companies that adapt and embrace new ideas often need help to keep up with the competition. However, fostering a culture of innovation takes much work. It takes vision, leadership and willingness to take risks in the right proportion. Sachin Dev Duggal, co-founder of Builder.ai, has perfected the art of this balance, creating a company culture where creativity and growth are nurtured at each stage.
The Art of the Pitch: WordPress Relationships and SalesLaura Byrne
Clients don’t know what they don’t know. What web solutions are right for them? How does WordPress come into the picture? How do you make sure you understand scope and timeline? What do you do if sometime changes?
All these questions and more will be explored as we talk about matching clients’ needs with what your agency offers without pulling teeth or pulling your hair out. Practical tips, and strategies for successful relationship building that leads to closing the deal.
SAP Sapphire 2024 - ASUG301 building better apps with SAP Fiori.pdfPeter Spielvogel
Building better applications for business users with SAP Fiori.
• What is SAP Fiori and why it matters to you
• How a better user experience drives measurable business benefits
• How to get started with SAP Fiori today
• How SAP Fiori elements accelerates application development
• How SAP Build Code includes SAP Fiori tools and other generative artificial intelligence capabilities
• How SAP Fiori paves the way for using AI in SAP apps
Smart TV Buyer Insights Survey 2024 by 91mobiles.pdf91mobiles
91mobiles recently conducted a Smart TV Buyer Insights Survey in which we asked over 3,000 respondents about the TV they own, aspects they look at on a new TV, and their TV buying preferences.
LF Energy Webinar: Electrical Grid Modelling and Simulation Through PowSyBl -...DanBrown980551
Do you want to learn how to model and simulate an electrical network from scratch in under an hour?
Then welcome to this PowSyBl workshop, hosted by Rte, the French Transmission System Operator (TSO)!
During the webinar, you will discover the PowSyBl ecosystem as well as handle and study an electrical network through an interactive Python notebook.
PowSyBl is an open source project hosted by LF Energy, which offers a comprehensive set of features for electrical grid modelling and simulation. Among other advanced features, PowSyBl provides:
- A fully editable and extendable library for grid component modelling;
- Visualization tools to display your network;
- Grid simulation tools, such as power flows, security analyses (with or without remedial actions) and sensitivity analyses;
The framework is mostly written in Java, with a Python binding so that Python developers can access PowSyBl functionalities as well.
What you will learn during the webinar:
- For beginners: discover PowSyBl's functionalities through a quick general presentation and the notebook, without needing any expert coding skills;
- For advanced developers: master the skills to efficiently apply PowSyBl functionalities to your real-world scenarios.
State of ICS and IoT Cyber Threat Landscape Report 2024 previewPrayukth K V
The IoT and OT threat landscape report has been prepared by the Threat Research Team at Sectrio using data from Sectrio, cyber threat intelligence farming facilities spread across over 85 cities around the world. In addition, Sectrio also runs AI-based advanced threat and payload engagement facilities that serve as sinks to attract and engage sophisticated threat actors, and newer malware including new variants and latent threats that are at an earlier stage of development.
The latest edition of the OT/ICS and IoT security Threat Landscape Report 2024 also covers:
State of global ICS asset and network exposure
Sectoral targets and attacks as well as the cost of ransom
Global APT activity, AI usage, actor and tactic profiles, and implications
Rise in volumes of AI-powered cyberattacks
Major cyber events in 2024
Malware and malicious payload trends
Cyberattack types and targets
Vulnerability exploit attempts on CVEs
Attacks on counties – USA
Expansion of bot farms – how, where, and why
In-depth analysis of the cyber threat landscape across North America, South America, Europe, APAC, and the Middle East
Why are attacks on smart factories rising?
Cyber risk predictions
Axis of attacks – Europe
Systemic attacks in the Middle East
Download the full report from here:
https://sectrio.com/resources/ot-threat-landscape-reports/sectrio-releases-ot-ics-and-iot-security-threat-landscape-report-2024/
Welocme to ViralQR, your best QR code generator.ViralQR
Welcome to ViralQR, your best QR code generator available on the market!
At ViralQR, we design static and dynamic QR codes. Our mission is to make business operations easier and customer engagement more powerful through the use of QR technology. Be it a small-scale business or a huge enterprise, our easy-to-use platform provides multiple choices that can be tailored according to your company's branding and marketing strategies.
Our Vision
We are here to make the process of creating QR codes easy and smooth, thus enhancing customer interaction and making business more fluid. We very strongly believe in the ability of QR codes to change the world for businesses in their interaction with customers and are set on making that technology accessible and usable far and wide.
Our Achievements
Ever since its inception, we have successfully served many clients by offering QR codes in their marketing, service delivery, and collection of feedback across various industries. Our platform has been recognized for its ease of use and amazing features, which helped a business to make QR codes.
Our Services
At ViralQR, here is a comprehensive suite of services that caters to your very needs:
Static QR Codes: Create free static QR codes. These QR codes are able to store significant information such as URLs, vCards, plain text, emails and SMS, Wi-Fi credentials, and Bitcoin addresses.
Dynamic QR codes: These also have all the advanced features but are subscription-based. They can directly link to PDF files, images, micro-landing pages, social accounts, review forms, business pages, and applications. In addition, they can be branded with CTAs, frames, patterns, colors, and logos to enhance your branding.
Pricing and Packages
Additionally, there is a 14-day free offer to ViralQR, which is an exceptional opportunity for new users to take a feel of this platform. One can easily subscribe from there and experience the full dynamic of using QR codes. The subscription plans are not only meant for business; they are priced very flexibly so that literally every business could afford to benefit from our service.
Why choose us?
ViralQR will provide services for marketing, advertising, catering, retail, and the like. The QR codes can be posted on fliers, packaging, merchandise, and banners, as well as to substitute for cash and cards in a restaurant or coffee shop. With QR codes integrated into your business, improve customer engagement and streamline operations.
Comprehensive Analytics
Subscribers of ViralQR receive detailed analytics and tracking tools in light of having a view of the core values of QR code performance. Our analytics dashboard shows aggregate views and unique views, as well as detailed information about each impression, including time, device, browser, and estimated location by city and country.
So, thank you for choosing ViralQR; we have an offer of nothing but the best in terms of QR code services to meet business diversity!
GDG Cloud Southlake #33: Boule & Rebala: Effective AppSec in SDLC using Deplo...James Anderson
Effective Application Security in Software Delivery lifecycle using Deployment Firewall and DBOM
The modern software delivery process (or the CI/CD process) includes many tools, distributed teams, open-source code, and cloud platforms. Constant focus on speed to release software to market, along with the traditional slow and manual security checks has caused gaps in continuous security as an important piece in the software supply chain. Today organizations feel more susceptible to external and internal cyber threats due to the vast attack surface in their applications supply chain and the lack of end-to-end governance and risk management.
The software team must secure its software delivery process to avoid vulnerability and security breaches. This needs to be achieved with existing tool chains and without extensive rework of the delivery processes. This talk will present strategies and techniques for providing visibility into the true risk of the existing vulnerabilities, preventing the introduction of security issues in the software, resolving vulnerabilities in production environments quickly, and capturing the deployment bill of materials (DBOM).
Speakers:
Bob Boule
Robert Boule is a technology enthusiast with PASSION for technology and making things work along with a knack for helping others understand how things work. He comes with around 20 years of solution engineering experience in application security, software continuous delivery, and SaaS platforms. He is known for his dynamic presentations in CI/CD and application security integrated in software delivery lifecycle.
Gopinath Rebala
Gopinath Rebala is the CTO of OpsMx, where he has overall responsibility for the machine learning and data processing architectures for Secure Software Delivery. Gopi also has a strong connection with our customers, leading design and architecture for strategic implementations. Gopi is a frequent speaker and well-known leader in continuous delivery and integrating security into software delivery.
GraphRAG is All You need? LLM & Knowledge GraphGuy Korland
Guy Korland, CEO and Co-founder of FalkorDB, will review two articles on the integration of language models with knowledge graphs.
1. Unifying Large Language Models and Knowledge Graphs: A Roadmap.
https://arxiv.org/abs/2306.08302
2. Microsoft Research's GraphRAG paper and a review paper on various uses of knowledge graphs:
https://www.microsoft.com/en-us/research/blog/graphrag-unlocking-llm-discovery-on-narrative-private-data/
Dev Dives: Train smarter, not harder – active learning and UiPath LLMs for do...UiPathCommunity
💥 Speed, accuracy, and scaling – discover the superpowers of GenAI in action with UiPath Document Understanding and Communications Mining™:
See how to accelerate model training and optimize model performance with active learning
Learn about the latest enhancements to out-of-the-box document processing – with little to no training required
Get an exclusive demo of the new family of UiPath LLMs – GenAI models specialized for processing different types of documents and messages
This is a hands-on session specifically designed for automation developers and AI enthusiasts seeking to enhance their knowledge in leveraging the latest intelligent document processing capabilities offered by UiPath.
Speakers:
👨🏫 Andras Palfi, Senior Product Manager, UiPath
👩🏫 Lenka Dulovicova, Product Program Manager, UiPath
Dev Dives: Train smarter, not harder – active learning and UiPath LLMs for do...
Thick film paste
1. WHITE PAPER SERIES
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Tel: (858) 558-6666
Three Roll Mill and Thick Film Paste
1. Introduction
Thick Film Materials is ink paste produced through mixing, kneading, and dispersing of
metal powders, glass powders, and inorganic oxides with organic solvent in a three-roll
mill. The think film pastes are screen-printed on ceramic boards or green sheets as circuit
patterns, and then burned. They are mainly used for various electronic components such
as multilayer chip capacitors, chip resistors, etc. These components are used in volume in
personal computers, mobile phones, etc. Depending on the application, the paste can act
as conductive materials, resistor materials and insulate materials. In conductor
compositions, the conductive phase is generally a precious metal or mixture of precious
metals. In resistor compositions the conductive phase is generally a metallic oxide. In
dielectric compositions, the functional phase is generally a glass or ceramic.
2. Ingredients of thick film paste
A thick film ink comprises main functional powder, glass frit, transitional metal oxide,
dispersing agent, and organic medium, which is typically solvent and organic binder,
serves as a vehicle to disperse the main functional powder.
There are three critical parameters of the paste that related to screen printing: (1) the ratio
of the solid contents, (2) the particle size distribution, and (3) viscosity.
The solids content (active element and adhesion element) as a ratio of the total weight of
the paste will dramatically affect the ability of the paste to be screened and also the
density of the fired film. If the solids content is high, the fired film will be dense, but will
also be difficult to screen. A typical value for thick-film conductors is 85-92%.
The particle size distribution of a thick film paste is a compromise between screenability
and the properties of the fired film. For screenability, it is desired to have very small
particles, but very small particle size in thick film resistors produce parameters that are
skewed and not suitable for most circuit applications. Larger particles will obviously be
more difficult to screen and may actually block one or more screen opening. Particle size
distribution may be measure in a manufacturing environment by the use of a fineness-of-
grind (FOG) gauge.
Viscosity is related to the molecular attraction within the body of the liquid and is the
ratio of the shear rate of the fluid (in sec-1
) to the shear stress (in force per unit area). The
viscosity measurement is usually employed by spindle method.
2.1 Functional ingredients
2.1.1 Conductive compositions
Any of the noble metals, their alloys or mixture may be used as the conductive phase.
Noble metals such as Ag, Pt, and Pb can be used and their alloys can be Pt/Au, Pd/Ag,
2. WHITE PAPER SERIES
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Tel: (858) 558-6666
Pd/Au and Ag/Pt/Pd. The particle size of conductive phase should be in the range 0.5-1.0
μm and a surface area of 1-12 m2
/g. The more preferable amount is 50-75 wt % of the
compositions, excluding the organic medium.
2.1.2 Resistor compositions
The thick film resistor composites generally comprise a mixture of electrically
conductive materials finely dispersed in an insulative glassy phase matrix. The
compositions should provide a wide range of sheet resistance (0.5 Ω/□ and higher than
1×109
Ω/□ and any intermediate resistance value)
The viscosity will be in the range of about 15-50 pascal-seconds (Brookfield RVT, 10
rpm, #5 spindle)
2.1.3 Dielectric composition
The main functional phase of the dielectric paste is ceramic compositions from Al2O3,
SiO2, CaO and MgO or the mixtures.
.
2.2 Glass frit
The glass fit powder is essential to the composition to promote adhesion to the substrate
and densification of the composition upon processing. The glass frit should be 3 to 4 wt%
of the whole ink amount. The glass frits most preferably used are the borosilicate frits,
such as lead borosilicate frit, bismuth, cadmium, barium, calcium or other alkaline earth
borosilicate frits. The preparation of such glass frits is well-known and consists in
melting together the constituents, and pouring such molten composition into water to
form the frit. The main materials are the transition metal oxide generally comprising zinc
oxide, titanium oxide, chromium (III) oxide, cadmium oxide and nickel (II) oxide. To
obtain the above desired oxide, the bath ingredients could be any compounds that yield
the desired oxides under the usual condition of frit production. For example, boric oxide
will be obtained form boric acid, silicon dioxide will be produced from flint, barium
oxide will be produced from barium carbonate, etc. The desirable amount is from 0.5 to
2.0 wt%.
2.3 Organic medium
Organic medium is the solution of organic binder solved into the solvent. The organic
solvent amount composing the vehicle should be 0.04 to 0.18 by weight to the whole
powder amount.
The solvent system is required to primarily dissolve the polymeric resin system (i.e.
organic binder) as well as adequately wet the substrate during the screen-printing
operation.
The solvent usually boils within the range of 130-350 ℃. Suitable solvents include
kerosene, mineral spirits, dibutylphthalate, butyl carbitol, butyl carbitol acetate, hexylene
glycol and high-boiling alcohols and alcohol esters. Various combinations of these and
3. WHITE PAPER SERIES
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Tel: (858) 558-6666
other solvents are formulated to obtain the desired viscosity, volatility and compatibility
with dielectric tape.
The primary function of organic binder is to bind together the main functional materials
such as conductive particles or resistor particles. In general, these consist of polyesters,
acrylics, vinyl or polyurethane polymers and may be combined to obtain optimum
properties.
The most frequently resin is ethyl cellulose. However, resins such as ethylhydroxyethyl
cellulose, wood rosin, mixtures of ethyl cellulose andphenolic resions,
polymerthacrylates of lower alcohols, and monobutyl ether or ethylene glycol
monoacetate can also be used. The weight-average molecular weight of the organic
binder is preferably 100,000 to 1,300. The content of the organic binder is preferably 2 to
15 wt% in the whole ink.
In additional, the thixotropic agents and wetting agents are also added into the solvent.
Thixiotropic agents are commonly hydrogenated castor oil, its derivatives and ethyl
cellulose. Of course, it is not always necessary to incorporate a thixotropic agent since
the solvent/resin properties couple with the shear thinning inherent in any suspension
may alone be suitable in this regard. The wetting agents include phosphate esters and
soya lecithin.
2.4 Other additives
Additives may also be employed to fine-tune viscosity for good screen printing
characteristics enabling accurate and reproducible production, or to modify the binder
system acting as, for example, a plasticizer to enhance flex properties. The additives
account for 0.05 to 5.0 wt% in the whole ink.
3. Process thick film paste
The ingredients (the particulate inorganic solids and the organic medium) of the paste are
first weighed together in a container. The components are then vigorously mixed to form
a uniform blend and then passed through three-roll mill to achieve a good dispersion of
particles. A Three Roll Mill is composed of three horizontally positioned rolls rotating at
opposite directions and different speeds (Fig. 1). When material is passed through the
first nip, between the feed roll and the center oil, it is subjected to high shear force
resulting in mixing, refining, dispersing and/or homogenizing of the material. When the
material passed through the second nip, between the center roll and the discharge roll, it
is again subjected to high shear force resulting in further mixing, refining, dispersing
and/or homogenizing of the material. Milled material is removed from the apron roll by a
knife that runs against the roll. The cycle can be repeated to improve dispersion until
equilibrium is reached. A Hegman gauge is used to determine the state of dispersion of
the particles in the paste. The satisfactory dispersion will give a fourth scratch point
of 10-18 μm. The viscosity of the paste is typically within the following ranges when
4. WHITE PAPER SERIES
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measured at room temperature on Brookfield viscometers at low, moderate and high
shear rates (showed in Table 1).
Figure 1 Schematic drawing of three-roll mill: (1) feed roll, (2) center roll, (3) discharge
roll, (4) discharge blade, (5) first nip, (6) second nip, and (7) apron
Table 1 Typical viscosity range of thick film paste
Shear Rate (Sec-1
) Viscosity (Pa.s)
0.2 100-5000 -
300-2000 Preferred
600-1500 Most preferred
4 40-400 -
100-250 Preferred
140-200 Most preferred
384 7-40 -
10-25 Preferred
12-18 Most preferred
4. Examples
4.1 Conductive paste
Examples are showed in Table 2-4 [1].
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Table 2 (Copper ink)
Copper (mean particle size 1.0 μm) 79 (parts by weight)
Glass frit (Nippon Electric Glass Co. GA-9 which
has the composition PbO.B2O3.SiO2)
3
ZnO (Kanto Chemical Co.) 1
i-BMA, α-MeSt resin (Sekisui Chemical Inc.
IBS-6) Weight average molecular weight 4750
10
solvent (Kanto Chemical Co., butylcarbitol
acetate)
6.6
Dispersing agent (alkyl-substituted
polyoxyethylene phosphate or alkylallyl-
substituted polyoxyethylene phosphate
0.4
Table 3 (Gold ink)
Gold (mean particle size 1.0 μm) 79 (parts by weight)
Glass frit (Nippon Electric Glass Co. GA-9 which
has the composition PbO.B2O3, SiO2)
3
ZnO (Kanto Chemical Co.) 1
i-BMA, α-MeSt resin (Sekisui Chemical Inc.
IBS-6) Weight average molecular weight 1360
9
solvent (Kanto Chemical Co., butylcarbitol
acetate)
7.6
Dispersing agent (alkyl-substituted
polyoxyethylene phosphate or alkylallyl-
substituted polyoxyethylene phosphate
0.4
Table 4 (Silver ink)
Silver (mean particle size 2.0 μm) 79 (parts by weight)
Glass frit (Nippon Electric Glass Co. GA-9) 3
ZnO (Kanto Chemical Co.) 1
i-BMA, α-MeSt resin (Sekisui Chemical Inc.
IBS-6) Weight average molecular weight 32060
10
solvent (Kanto Chemical Co., butylcarbitol
acetate)
6.6
Dispersing agent (alkyl-substituted
polyoxyethylene phosphate or alkylallyl-
substituted polyoxyethylene phosphate
0.4
6. WHITE PAPER SERIES
www.threerollmill.com
Tel: (858) 558-6666
4.2 Resistor paste
Table 5 Example of resistor paste [2]
Example 1 Example 2
TiSi2 29.2% 12%
Ti5Si3 0% 18%
Al2O3 2.6% 0%
Glass I 68.2% 35%
Glass II 0% 35%
The first glass: 5-10% SiO2, 30-50% BaO, 40-60% B2O3 and 1 to 5% CuO
The Second glass” 50 to 70% B2O3, 25 to 40% SrO, and 2 to 10% SiO2
4.3 Dielectric paste
Table 6 Example of dielectric paste [3]
Compositions
SiO2 B2O3 Al2O3 BaO Na2O K2O Li2O
Glass 1 60 30 5 3 1 0.6 0.4
Al2O3 SiO2 CaO MgO
Ceramic 1 100 0 0 0
Ceramic 2 95 5 0 0
Note: Sample 1 is ceramic 1 + glass 1 with ration of 50/50, Sample 2 is ceramic 2 + glass
2 with ration of 50/50
5. Conclusion
The three-roll mill has been used in thick film materials manufactures. The mills with
different sizes are good for laboratories and small production run to large batch
production. Our products [4] provide a great deal of flexibility in designing a machine
that best meets the customers’ specific application. We pursue our products to reach the
most precise requirements for dispersing, refining, shearing, particle size reduction,
homogenizing, blending, mixing and de-aearting. We continue to seek out unique
applications with our high quality product and service.
Reference:
1. Satoru Fujii, Hirotoshi Watanabe, Conductive ink composition and method of
forming a conductive thick film pattern, 1992, US Patent 5366760
2. Charles C. Y. Kuo, Thick film Resistive Paint and Resistors made therefrom,
1985, US Patent 4639391
3. Satorn Yuhaku, Seiichi Nakatani, Tsutomu Nishimura, and Toru Ishida, Dielectric
paste and method of manufacturing the paste, 1986 US Patent 4812422
4. www.threerollmill.com