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Sunday, September 29, 2013

Tissue Softness Comparison


Tissue softness and optical properties such as brightness and color share similar characteristics. Many years ago, most considered the best tool for evaluating optical properties to be the human eye. Modern tools like the spectrophotometer today help us quantify what the human eye perceives. For tissue, the human hand has long been considered the best tool for determining tissue softness. The difficult reality is that any subjective evaluation creates uncertainty and uncertainty leads to variation. Variation is the enemy of consistency and quality.


Simply put, the Emtec Tissue Softness Analyzer (TSA) is a tool that quantifies the otherwise subjective hand feel or “softness” evaluation of tissue.



Many aspects of tissue production have long been considered “art” rather than science. The subjective nature of hand feel is a perfect example. Anyone can rank order tissue samples in order of perceived softness, but can you get a group of people (especially papermakers) to agree? The Emtec Tissue Softness Analyser (TSA) quantifies different components associated with “hand feel” or softness perception into a single numerical value that can be used as an indication of “tissue softness.”



Why is the TSA beneficial?

1.   The TSA is fast and easy to use. Anyone can learn to use the TSA to determine a measurement value indicative of tissue softness. That measure is the tissue softness index.

2.   With quantified measurements, process parameters such as crepe or furnish can be optimized to improve softness.

3.   With a measurement tool, benchmarking becomes easier. The graph (below) illustrates benchmark results for several different retail brands of bath tissue.

4.   With the TSA, customer feedback or feedback from “Hand Feel” panels can be quantified, and from that feedback, product specifications are improved.



With meaningful product specifications, I have historically seen more stable production. Stability and consistency are hallmarks of higher quality. If you want to improve the quality of your tissue products, try the Emtec TSA or consider sending in samples of your current tissue.

Thursday, September 26, 2013

Service Technician Needed for South US

Technidyne is in the process of hiring a Service Technician located in the southern US.  We have posted notices with CareerBuilder in Atlanta, GA - Shreveport, LA and Jackson, MS.  If you or a colleague would like to be a part of the Technidyne family, please go to our link.

Tuesday, September 24, 2013

Visit to China

September 17th, Paul Crawford (Business Director - Asia) and I spent time with Mr. Max Liu, General Manager, of Jiu Mao International Trading Co. our agent in China and Taiwan.  Jiu Mao offers high quality testing equipment from around the world as well as technical support and complete after-sales services to the Pulp, Paper and Printing Industries.

Sunday, September 22, 2013

ISO vs. TAPPI Opacity: What are the differences?

In the Paper Industry, there are two different standards for opacity measurement.  ISO 2471 and TAPPI T425 are the relevant standards here.

The differences between the two are:


ISO
TAPPI
Geometry
d/0°
15°/d
White Backing
R
R0.89
Wavelength
557nm
572nm

Opacity is the characteristic ability of a material to hide from view a non-active backing materialWhen reading a book, one prefers to read one page at a time, rather than read all of the pages at once.  Each page must have sufficient opacity to obscure the printing on the subsequent pages.  If the intended use of the paper is to allow the objects placed behind it to be seen, such as glassine, then transmittance measurements should be utilized rather than opacity measurements.  To simulate viewing conditions a ratio means of opacity measurement has been adopted by the paper industry and has been used for many years.

ISO (Printing Opacity) =  R0 / R


TAPPI (Contrast Ratio) = R0 / R0.89 

Differences in the measurements can be seen here. 

GEOMETRY

ISO 2471 utilizes the diffuse illumination and 0° viewing geometry (d/0°) which is the same as the ISO Brightness geometry.  TAPPI T425 uses 15° illumination and diffuse viewing (15°/d) originally developed by Bausch & Lomb in the 1930's.

BACKING
Both methods use a contrast between the sheet to be measured backed with a black backing (R0) and the same sheet backed with 'white'. The difference is what each uses as the 'white' backing.  ISO 2471 uses an infinite pad (R) as the white backing.  TAPPI T425 uses an 89% white body backing (R0.89).

WAVELENGTH
ISO 2471 specifies a response of YC , which has an effective wavelength of 557 nm.  In TAPPI T425, the specified response is YA , which has an effective wavelength of 572 nm.  Unlike brightness, which is measured in the blue portion of the spectrum, opacity is predominately measured in the green or greenish yellow portion of the spectrum with some response throughout the entire visible spectrum.  The objective is to measure opacity using a spectral response that correlates closely with human observation.

FOOTNOTE
Many of the geometric and spectral variables are less critical for opacity measurements than for brightness and color because opacity is a ratio measurement.  For example if a sample being measured is glossy, nearly the same amount of gloss will be present in the numerator and denominator of the ratio causing most of the gloss effect to be canceled out. Similarly the effect of fluorescence on opacity is minimized by the ratio calculated that is inherent in the determination of opacity.


This is not a full discussion of opacity, but a quick synopsis.  Keep in mind that:

TAPPI Opacity is measured using:
  • Technidyne BNL-3
  • Technidyne PROFILE/Plus TAPPI Opacity
  • Technidyne Model 425
  • Brightimeter Micro S-5

ISO Opacity is measured using:
  • Technidyne Color Touch, Color Touch 2 and PC
  • Technidyne PROFILE/Plus Color Touch
  • Technibrite TB-1 and Micro TB-1C

Thursday, September 19, 2013

Visit to Department of Science Service - Thailand

On Friday, September the 13th (it really wasn't scary at all), Paul Crawford (Business Director - Asia), and I visited long-time friend and customer, Dr. Poovadee Tuchinda.  Ms. Tuchinda is a Researcher at the Department of Science Service in Thailand. Her primary responsibilities are in the area of Forest & Paper Products.

We talked about the current economy in Thailand which seems to be declining a bit.  Also, we discussed the government's approach to the industry, budgets and priorities.  We also discussed some issues related to ISO TC6.  It was great to get some insight on the status of business in Thailand.

We wish Ms. Tuchinda the best for the remainder of 2013! Thanks for letting us catch up on things.

Wednesday, September 18, 2013

Visit to Thailand

September 13th, Paul Crawford (Business Director - Asia) and I spent time with Mr. Ankrin  Kaewpralom, General Manager, of Certified Lab Consulting or CLC, our agent in Thailand.  CLC is offers total solutions, high quality products from around the world including technical support and complete after-sales services to Film & Plastic, Pulp & Paper, Packaging& Wrapping, Ink & Printing and Textile & Nonwoven industries in Southeast Asia at a reasonable cost.

We discussed the current market in Thailand, Malaysia and Vietnam.  As seen in the picture above, CLC has committed to sending technicians to Technidyne's headquarters for in-depth service training.  CLC has done a great job with service for its customers in this region, and we were able to thank them personally for their efforts.


Tuesday, September 17, 2013

Visit to Indonesia

September 9-11, Paul Crawford (Business Director - Asia), and I visited our agent in Indonesia, PT Pintu Mas Mulia Kimia.  PT Pintu Mas Mulia Kimia (PMMK) was established in 1981. It is a privately owned company, engaged in the business of chemicals, machinery & parts, and laboratory testing instruments supply to a number of industries.
The Executive Director, Mr. Wirawan Hongga, led our discussion with the staff of PMMK.  We discussed a number of projects throughout Indonesia. We also looked at the resources of PMMK and plans for the future.  Technidyne has worked with PMMK in Indonesia for over 20 years.  The relationship allows customers in Indonesia to use the latest technology in the Paper Industry with extremely good, local technical support and service.  PMMK has invested in service training at Technidyne's headquarters and keeps in close contact with the Technical Service personnel at Technidyne.

At the end of our stop, we were given a tour of Taman Mini Indonesia Indah or 'Little Indonesia'.  This is huge park!  With 13,000 islands and 27 provinces, it's hard to see all of Indonesia. Taman Mini Indonesia is a park filled with famous buildings from all parts of Indonesia and authentic examples of the various cultures through Indonesia. The park includes a sky-car tour, IMAX theatre, dances, and cultural events. The name translates as Beautiful Indonesia Miniature Park.  It was a great conclusion to our time in the Jakarta area.

Thanks to the people of PT Pintu Mas Mulia Kimia for their continued good work, hospitality and professionalism.

Sunday, September 15, 2013

TAPPI Brightness for High OBA Samples

TAPPI Optical Properties Committee is running a round robin on a new verification standard that will be used with high OBA samples.

When the TAPPI directional (45 degree illumination/0 degree viewing) geometry was introduced in the 1930's, it included the effects of fluorescence in its measurements. However, it did not have the ability to measure the effectiveness of these additives.  As optical brighteners and fluorescing agents became more common and more expensive, they needed to be measured and controlled. It wasn't until the 1980's that the TAPPI geometry brightness tester was equipped with the ability to measure the fluorescent component of brightness.  Fluorescent component is the additional brightness obtained from the use of optical brighteners. It is determined by measuring the sample with and then without the effect of UV energy on the sample.

Once this capability was added to the directional geometry instrument, the TAPPI Test Method T452 was updated with this information.  Even today this can be found in Appendix C.

As the use, effectiveness and cost of OBA and FWA continue to increase, it has become more important to accurately measure samples with very high levels of these additives.  The round robin within TAPPI will help establish:
  1. A procedure for this process
  2. A way to verify the calibration
  3. Tolerances of brightness at these very high levels of OBA and/or FWA
If you are still using TAPPI, directional geometry equipment, we would like to know. Please contact me at toddp@technidyne.com and let me know what device you may be using, what properties you measure (color, brightness, fluorescence, whiteness) and how often you use this device.  You may be able to assist in the process of updating this Test Method.

Sunday, September 8, 2013

Smoothness: Increasing & Decreasing

The biggest factors affecting smoothness of paper tend to be mechanical, rather than chemical. In particular, the type and extent of calendering usually causes the largest change in paper smoothness and density as the sheet passes through the system. Smoother paper can be achieved by increasing the nip pressures in calendering and by wetting the sheet with a mist spray or wet-box application before the web passes through a nip. Increased refining also tends to yield a smoother sheet.

Since calendering makes paper denser at the same time that it makes the paper smoother, papermakers are continually wrestling with issues of trying to separate these two variables. A common approach is to try to bulk up the paper, decreasing its apparent density, so that it then can be calendered back to the desired final smoothness and caliper. Wet-end additives that have been found to be most effective for lowering the density of paper include thermomechanical pulp (TMP) fibers and structured fillers such as scalenohedral (rosette shaped) precipitated calcium carbonate (PCC) filler.

Very high levels of smoothness can be achieved by conventional water-based mineral coatings, usually applied with a blade. Uncoated products can approach similar levels of smoothness and gloss only when using specialized equipment such as supercalenders, soft-nip calendered, or highly polished Yankee cylinder dryers.

To achieve rougher paper it is first necessary to back off on calendering. One might also consider increasing the amount of coarse fibers, such as softwood TMP or kraft fibers having a low degree of refining.

References
Smook, G. A., Handbook for Pulp and Paper Technologists, Angus Wilde Pub., Vancouver, 1992, ISBN 0-9694628-1-6. [Calendering practices]

Vreeland, J. H., Ellis, E. R., and Jewett, K. B., "Substrata Thermal Molding. Part 1. A Breakthrough in the Understanding and Practice of the Hot Calendering of Paper," Tappi J. 72 (11): 139 (1989); and "Part . Putting Theory into Practice," Tappi J. 72 (12): 201 (1989).

Sunday, September 1, 2013

Case Study: Reduce Roll Rejects



One of the worst things to happen in manufacturing is when your customer rejects your product. A paper mill that manufactures a coated paper was being plagued by product rejects on a specific grade. The end user complained of printability issues. The print would not hold ink across sections of the paper. The problem was not always there, but often enough that they were losing confidence in the mill's ability to provide a consistent product. The paper mill tried many things over the course of a year to figure out what was causing the issue. Retesting the rejected product did show an issue with the surface coating, however, the paper mill was unable to detect the problem during the manufacturing process.


This paper mill performed manual testing. Several spots across the web would be tested for various properties. Unfortunately, the areas with the issue were often missed. Fortunately the paper mill installed a Technidyne PROFILE/Plus System. Finally, the paper mill was able to see a true, high-frequency profile of the data across the web for the first time. It was always exciting to watch a customer get excited using your product to resolve a long standing issue.


Quickly the paper mill was questioning their long-standing paper making process. Based on the profile data which provided more data points across the web, they began tweaking the process to tighten up specs across the machine. With the data from the PROFILE/Plus automated testing system, they could identify the spots across the paper machine and offline coaters that had issues:

  • caliper problems 44 inches from the front side
  • surface scratch due to worn doctor blades 150 inches from the front side
  • loose roller sections on offline coaters at specific locations

Within two months the customer happily reported that they were producing a higher quality product. They attributed this to the higher frequency automated testing provided by the PROFILE/Plus. The ability to quickly and easily see a full profile of data helped this paper mill reduce roll rejects and other customer issues. The paper mill was doing a good job before, but now are doing a great job.


Learn more about automated testing and see a video of PROFILE/Plus and automated Tensile.

This case study was submitted by PROFILE/Plus Specialist, Mike L.