scholarly journals Effect of Plasma Surface Modification on Print Quality of Biodegradable PLA Films

2021 ◽  
Vol 11 (17) ◽  
pp. 8245
Author(s):  
Joanna Izdebska-Podsiadły
Keyword(s):  
High Surface ◽  
Argon Plasma ◽  
Strength Properties ◽  
Contact Angles ◽  
Print Quality ◽  
Plasma Surface ◽  
Plasma Activation ◽  
Printing Inks ◽  
Modification Of The Surface

PLA films, as non-absorbent materials, require modification of the surface before the printing process in order to improve the wettability of the substrate and to obtain proper ink adhesion to the substrate. In this paper, the surfaces of two kinds of PLA films were modified using plasma activation with parameters enabling high surface free energy (SFE) values, and then the films were printed on using different kinds of flexographic inks. Two gases, oxygen and argon, were used for activation, as these make it possible to obtain good hydrophilicity and high SFE values while having different effects on the roughness, or the degree of surface etching. Plasma-activated films were subsequently subjected to the measurements of: contact angle with water, diiodomethane and three printing inks, roughness, weight change, strength properties, color and gloss change, and SFE was determined. Unmodified and activated films were flexographically printed in laboratory conditions and then the quality of obtained prints was analyzed. The results showed a strong effect of activation with both oxygen and argon plasma on the SFE value of the films and the contact angles of water and inks, with the gas used for plasma activation and the type of film significantly influencing the thickness of the fused ink layer and the resultant color. Moreover, plasma activation had a especially favorable and significant effect on the quality of prints made with water-based inks, while it had little effect when printing with solvent-based inks.

scholarly journals The examination of vegetable- and mineral oil-based inks’ effects on print quality: Green printing effects with different oils

2018 ◽  
Vol 16 (3) ◽  
pp. 137-143 ◽  
Author(s):  
Cem Aydemir ◽  
Semiha Yenidoğan ◽  
Arif Karademir ◽  
Emine Arman Kandirmaz
Keyword(s):  
Soybean Oil ◽  
Color Change ◽  
Water Drop ◽  
High Surface ◽  
Film Surface ◽  
Mineral Oil ◽  
Contact Angles ◽  
Print Quality ◽  
Offset Printing ◽  
Light Fastness

Introduction: Printing inks oil selection is related to the desired nature of the varnish in the ink production. Petroleum-derived mineral oils and vegetable oils can be used in offset inks. Methods: In this study, the behaviors of vegetable- and mineral oil-based inks on uncoated and coated paper surfaces were investigated in terms of printability. Solid tone test prints were done with offset printing of these inks. Print gloss of the printed samples was measured and a light fastness test was implemented on these samples in order to determine the resistance to fading. Absorption behavior and contact angles of the ink-printed films on the test papers were measured with the sessile water drop method depending on time, and surface energies were calculated. Results: On both paper types, linseed–soybean oil-based vegetable ink gave the highest brightness value. The lowest print gloss results on the paper were obtained from soybean oil-based inks. The lowest color change was recorded with mineral oil-based inks on gloss-coated papers. According to the ink-film–surface relation, when the contact angle is high, surface energy decreases and the absorbency of the ink-film is lower. Conclusions: In this study, the behaviors of vegetable- and mineral oil-based inks on different paper surfaces, and the effect on the quality of printability as well as differences, have been evaluated, taking environmental and health factors into consideration.

Effect of ink and paperboard characteristics on flexographic print quality based on print density

TAPPI Journal ◽  
2011 ◽  
Vol 10 (9) ◽  
pp. 7-13
Author(s):  
KHODADAD MALMIRCHEGINI ◽  
FARSHAD SARKHOSH RAHMANI
Keyword(s):  
Water Absorption ◽  
Significant Influence ◽  
Particle Diameter ◽  
Print Quality ◽  
Printing Technology ◽  
Plastic Films ◽  
Printing Inks ◽  
Packaging Industry ◽  
Solids Content ◽  
Density Results

Flexography is an evolving printing technology that is suitable for printing on coated and uncoated paperboard and board, nonporous substrates including metalized and paperboard foils, and plastic films used especially in the packaging industry. This study evaluated the effect of paperboard and ink characteristics on flexographic print density in paperboard. Three commercial paperboards from different companies were prepared: brown kraft from Thailand, white kraft from Spain, and test liner from Iran. Four samples of process print inks from Iran were used in this investigation. Paperboard properties, such as roughness and water absorption, and ink characteristics, including solids content, PH and particle diameter, were measured. The inks were printed on paperboards using a roll no.15 applicator with a blade metering device, and the print densities were measured. Results showed that solids content, pH, and particle diameter of printing inks influenced print density, while the roughness and water absorption of the three types of paperboard had no significant influence on print density. Results also illustrated that two levels of ink viscosity (25–30 and 50–55 mPa·s) were insignificant to print density.

Flexographic ink-coating interactions: effects of latex variations in coating layers

TAPPI Journal ◽  
2016 ◽  
Vol 15 (4) ◽  
pp. 253-262 ◽  
Author(s):  
ERIK BOHLIN ◽  
CAISA JOHANNSON ◽  
MAGNUS LESTELIUS
Keyword(s):  
Contact Angles ◽  
High Ratio ◽  
Print Quality ◽  
Particle Sizes ◽  
Mixed Composition ◽  
Coating Surface ◽  
Covered Area ◽  
Surface Optical ◽  
Flexographic Printing ◽  
Coating Formulation

The effect of coating structure variations on flexographic print quality was studied using pilot-coated paperboard samples with different latex content and latex particle sizes. Two latexes, with particle sizes of 120 nm and 160 nm, were added at either 12 parts per hundred (pph) or 18 pph to the coating formulation. The samples were printed with full tone areas at print forces of 25 N and 50 N in a laboratory flexographic printing press using a waterbased ink. A high ratio of uncovered areas (UCAs) could be detected for the samples that contained 18 pph latex printed at a print force of 25 N. UCAs decreased with increased print force and with decreased amounts of latex in the coating formulation. The fraction of latex covered area on the coating surface was estimated to be 0.35–0.40 for the 12 pph, and 0.70–0.75 for the 18 pph samples. The ink penetration depth into the coating layer could be linked to the fraction of latex-free areas on the coating surface. Optical cross section microscopy indicated that a higher printing force did not increase the depth of penetrated ink to any greater extent. Higher printing force did increase contact between plate and substrate, leading to an improved distribution of the ink. This, in turn, increased print density and decreased UCAs. On closer inspection, the UCAs could be categorized as being induced by steep topographic changes. When appearing at other locations, they were more likely to be caused by poor wetting of the surface. To understand the wetting behavior of the coating surface, observed contact angles were compared with calculated contact angles on surfaces of mixed composition.

Lignin-Containing Photoactive Resins for 3D Printing by Stereolithography

2018 ◽  
Author(s):  
Jordan T. Sutton ◽  
Kalavathy Rajan ◽  
David P. Harper ◽  
Stephen Chmely
Keyword(s):  
Additive Manufacturing ◽  
New Products ◽  
High Surface ◽  
Fold Increase ◽  
Print Quality ◽  
Renewable Materials ◽  
Lignin Concentration ◽  
Environmentally Sustainable ◽  
Manufacturing Applications ◽  
Modified Lignin

Generating compatible and competitive materials that are environmentally sustainable and economically viable is paramount for the success of additive manufacturing using renewable materials. We report the successful application of renewable, modified lignin-containing photopolymer resins in a commercial stereolithography system. Resins were fabricated within operable ranges for viscosity and cure properties, using up to 15% modified lignin by weight with the potential for higher amounts. A four-fold increase in ductility in cured parts with higher lignin concentration is noted as compared to commercial SLA resins. Excellent print quality was seen in modified lignin resins, with good layer fusion, high surface definition, and visual clarity. These materials can be used to generate new products for additive manufacturing applications and help fill vacant material property spaces, where ductility, sustainability, and application costs are critical.

Lignin-Containing Photoactive Resins for 3D Printing by Stereolithography

2018 ◽  
Author(s):  
Jordan T. Sutton ◽  
Kalavathy Rajan ◽  
David P. Harper ◽  
Stephen Chmely
Keyword(s):  
Additive Manufacturing ◽  
New Products ◽  
High Surface ◽  
Fold Increase ◽  
Print Quality ◽  
Renewable Materials ◽  
Lignin Concentration ◽  
Environmentally Sustainable ◽  
Manufacturing Applications ◽  
Modified Lignin

Generating compatible and competitive materials that are environmentally sustainable and economically viable is paramount for the success of additive manufacturing using renewable materials. We report the successful application of renewable, modified lignin-containing photopolymer resins in a commercial stereolithography system. Resins were fabricated within operable ranges for viscosity and cure properties, using up to 15% modified lignin by weight with the potential for higher amounts. A four-fold increase in ductility in cured parts with higher lignin concentration is noted as compared to commercial SLA resins. Excellent print quality was seen in modified lignin resins, with good layer fusion, high surface definition, and visual clarity. These materials can be used to generate new products for additive manufacturing applications and help fill vacant material property spaces, where ductility, sustainability, and application costs are critical.

scholarly journals A Comprehensive Investigation on 3D Printing of Polyamide 11 and Thermoplastic Polyurethane via Multi Jet Fusion

Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2139
Author(s):  
Wei Shian Tey ◽  
Chao Cai ◽  
Kun Zhou
Keyword(s):  
Tensile Strength ◽  
Flexural Strength ◽  
Wear Rate ◽  
Mechanical Performance ◽  
Thermoplastic Polyurethane ◽  
Print Quality ◽  
Polyamide 11 ◽  
Powder Bed

Multi Jet Fusion (MJF) is a recently developed polymeric powder bed fusion (PBF) additive manufacturing technique that has received considerable attention in the industrial and scientific community due to its ability to fabricate functional and complex polymeric parts efficiently. In this work, a systematic characterization of the physicochemical properties of MJF-certified polyamide 11 (PA11) and thermoplastic polyurethane (TPU) powder was conducted. The mechanical performance and print quality of the specimens printed using both powders were then evaluated. Both PA11 and TPU powders showed irregular morphology with sharp features and had broad particle size distribution, but such features did not impair their printability significantly. According to the DSC scans, the PA11 specimen exhibited two endothermic peaks, while the TPU specimen exhibited a broad endothermic peak (116–150 °C). The PA11 specimens possessed the highest tensile strength in the Z orientation, as opposed to the TPU specimens which possessed the lowest tensile strength along the same orientation. The flexural properties of the PA11 and TPU specimens displayed a similar anisotropy where the flexural strength was highest in the Z orientation and lowest in the X orientation. The porosity values of both the PA11 and the TPU specimens were observed to be the lowest in the Z orientation and highest in the X orientation, which was the opposite of the trend observed for the flexural strength of the specimens. The PA11 specimen possessed a low coefficient of friction (COF) of 0.13 and wear rate of 8.68 × 10−5 mm3/Nm as compared to the TPU specimen, which had a COF of 0.55 and wear rate of 0.012 mm3/Nm. The PA11 specimens generally had lower roughness values on their surfaces (Ra < 25 μm), while the TPU specimens had much rougher surfaces (Ra > 40 μm). This investigation aims to uncover and explain phenomena that are unique to the MJF process of PA11 and TPU while also serving as a benchmark against similar polymeric parts printed using other PBF processes.

scholarly journals Washing treatment impact on print quality of screen printed knitted fabrics

2016 ◽  
Vol 21 (3) ◽  
pp. 817-826
Author(s):  
Mladen Stančić ◽  
Branka Ružičić ◽  
Nemanja Kašiković ◽  
Dragana Grujić ◽  
Dragoljub Novaković ◽  
...  
Keyword(s):  
Print Quality ◽  
Knitted Fabrics ◽  
Screen Printed

scholarly journals Erratum

1995 ◽  
Vol 15 (4) ◽  
pp. 719-719
Keyword(s):  
Magnetic Resonance Imaging ◽  
Blood Flow ◽  
Electrical Impedance ◽  
Neonatal Rat ◽  
Print Quality ◽  
Resonance Imaging ◽  
Excitotoxic Injury ◽  
Cereb Blood Flow ◽  
Neonatal Rat Brain

Early Evolution and Recovery from Excitotoxic Injury in the Neonatal Rat Brain: A Study Combining Magnetic Resonance Imaging, Electrical Impedance, and Histology Menno van Lookeren Campagne, Jeroen B. Verheul, Klaas Nicolay and Robert Balázs [Originally published in J Cereb Blood Flow Metab 1994;14(6):JOll-J023] The print quality of Fig. 6G in the above article was poor and the figure therefore lacked the necessary detail. The publisher apologizes for this and reprints Fig. 6 , in its entirely, with the legend below. [Figure: see text]

scholarly journals ANALYZING THE EFFECT OF DENSITY VALUE DEVIATION ON PRINT QUALITY

KREATOR ◽  
2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Soebardianto . ◽  
Septia Ardiani ◽  
Romi Setiawan
Keyword(s):  
Quality Control ◽  
Quality Parameters ◽  
Quality Level ◽  
Print Quality ◽  
Machine Material ◽  
Digital World ◽  
Quality Control Parameters ◽  
Density Values ◽  
Standard Density

The quality control activities, in particular the measurement of density values, are part of the quality control parameters carried out by each company. Companies sometimes forget about the quality parameters of the name, even though the quality can give the printed products a good guarantee in the eyes of consumers. To achieve the quality level, of course, the business does not stand idle, there are several things that need to be done or provided by the business to support the quality, namely man (human), machine (machine), material (material), and method (method). In the development of technology in an increasingly advanced digital world, companies want to continue to compete with a digital world by making inroads, this of course gives the products produced by the company a good or a good level of quality. In this discussion, there is an identification of problematic aspects arising from the deviation of density values as well as ways to obtain standard density values and factors that affect the quality of prints on book cover prints using a Heidelberg machine.Keywords—Quality Control, Density, Standart, Product, Deviation

Diameter and strength of Ethiopian pure and cross-breed sheep wool fibers

2021 ◽  
Vol 16 ◽  
pp. 155892502110469
Author(s):  
Dereje Berihun Sitotaw ◽  
Addisu Ferede Tesema ◽  
Adane Haile Woldemariam
Keyword(s):  
Relative Humidity ◽  
Strength Properties ◽  
Wool Fiber ◽  
Main Body ◽  
Body Parts ◽  
Wool Fibers ◽  
Breed Sheep ◽  
Different Parts ◽  
Sheep Wool

The wool fibers fineness and strength have a remarkable role to determine the quality of yarn and the subsequent fabrics. The fineness property of the wool fibers is a crucially important fiber property for grading, classifying, selecting for particular applications such as for suit, blanket, shirt, carpet, and so on. The fineness and strength properties of four indigenous (Menz, Wollo, Farta, Tikur), three exotic (Awasi, Dorper, Corrediale), and four cross-breed (50% Dorper, 50% Awasi, 75% Awsi, Washera/Awasi) sheep wool fibers from the four main body parts (sides, neck, back, and belly) at six teeth removed age of 11 different sheep breeds have been investigated. The samples of wool fibers have been conditioned for 24 h at 20ºC ± 1ºC temperature and 65% ± 2% relative humidity. The specimen for sampling has been determined based on ASTM D2130-01. The results revealed that the fineness and strength of whole fibers taken from different parts of sample sheep varied significantly within the breed and among the breeds. The result revealed that the strength and fineness of the wool fibers have a positive correlation and Ethiopian sheep wool fiber is suitable for numerous types of classical and technical applications.

Sign in / Sign up

Export Citation Format

Share Document