Aluminum Packaging Research Articles

Detection of aluminium residue in sauces packaged in aluminium pouches

The interactions between food and aluminium packaging can be a potential source of aluminium release which can contribute to aluminium ingestion in the human body. Hence, it is important to identify the possible effects of such an interaction. The purpose of this study was to compare the aluminium content and the pH levels of three different types of sauces, packaged in aluminium packaging at two different temperatures and at two different periods in time. A three way analysis of variance test was utilized and the samples were stored at 22 °C (ambient room temperature) and at 50 °C. Stored samples showed minor changes in the aluminium contents when compared with fresh samples. Negligible changes in pH levels over the entire length of the study were observed for all three samples. The results of this study suggest that there is little cause for concern about possible aluminium accumulation in sauces packaged in aluminium packaging.

Clariant expands range of high-performance stabilizers

Polymer laminated aluminum packaging (PLAP) materials are very useful in high strength flexible packaging applications. Despite the advantages they can offer, there are several difficulties to recycle PLAP into its original metallic form. This study focuses on the effect of different polymeric laminates on the quality of the Al surface recycled by the thermal disengagement technology (TDT). Three different types of flexible PLAP materials have been thermally disengaged in an inert and air atmosphere in 5–30 min at 450 °C, 500 °C, 550 °C, and 600 °C. Released gases during the degradation of the polymers have been continuously monitored. After the thermal disengagement of the PLAP material, the surface oxidation was compared with the non-laminated aluminum surfaces that have gone through the same treatment process in the oxygen-enriched atmosphere for 20 min. Complete degradation of the polymers and the dissociation of the volatiles from the PLAP materials was achieved at 550 °C within 20 min of the heating process. IR gas analyzer detected hydrogen as the main component from the off gases along with some other greenhouse (CO, CO2) and hydrocarbon (CH4) gases. FTIR, XRD, SEM with EDS mapping, and XPS analysis of the disengaged aluminum (DAl) surfaces demonstrate the rate of oxidation on the non-laminated aluminum is 70–90% higher compared to recycled aluminum from the PLAP materials. A proper selection of TDT parameters minimizes the surface oxidation by the decomposition of the laminated polymers and provides optimum protection against oxidation of the aluminum by the polymers at the initial stage and its degradation components at the final stage by creating a barrier between the Al and surrounding atmosphere. This research shows a pathway to recycle complex packaging materials into less contaminated aluminum without any metal loss. Moreover, highly efficient fuel gas (mainly H2) and free carbon can also be isolated upon further processing of the off-gases and polymer degraded carbonaceous residue.

Structured LiI scintillator for thermal neutron imaging

We are currently developing high-resolution high-efficiency microcolumnar LiI films for thermal neutron imaging. The films are produced by the vapor deposition of LiI on a fiber-optic substrate and hermetically sealed in a specially designed aluminum package. Our work has produced up to 1.2-mm-thick films with column diameters of approximately 30 /spl mu/m. We have also performed imaging studies by optically coupling some of these films to a fiber-optic taper-based charge-coupled device. The imaging performance of the system was experimentally evaluated at Radiation Monitoring Devices, Inc., as well as at the thermal neutron port of the University of Massachusetts Lowell Research Reactor. The LiI films exhibited excellent scintillation characteristics with a spatial resolution as high as 4.5 lp/min (line pairs per millimeter). This paper outlines the film characterization and performance evaluation conducted during the course of the study. The new sensor described here is expected to usher in the development of large-area high-resolution digital thermal neutron detectors with improved detection efficiency and dynamic range and faster readout times than the current sensors.

The RECAL Foundation Programme; an example of ecological education in Poland

Abstract The issue of municipal waste management is becoming more and more topical in Poland due to its increasing volume, the current lack of an efficient waste management system and the low public awareness of the situation. In 1995 the Foundation of Aluminium Package Recovery (RECAL) was established to promote better methods of aluminium recycling. RECAL comprises the ‘School Can Programme’ and provides technical and educational assistance to municipalities. The Foundation supplies schools and municipalities with informative educational materials on waste management (aluminium recycling included), carton containers and bags for aluminium cans, selection magnets and lists of local collecting depots. The RECAL Programme has succeeded in raising public awareness and increasing in aluminium tonnage for recycling purposes in various regions of Poland. The details of the programme, its impact and effectiveness on the public will be discussed in this paper.

Microwave technology and foods

This chapter provides an overview of microwave applications in the food industry. Microwave and microwavable food today constitute an important segment of the food market in Japan, the US and increasingly in Western Europe. The growing number of microwave ovens and microwave foods greatly influenced the food packaging industry. Requirements of microwave compatibility changed the way in which the food industry selects food packaging. For prepared foods, microwave-transparent plastic and paperboard packaging has grown at the expense of aluminum packaging. A vast number of packaging designs, specific to microwave heating, have been developed. The most striking example is the so-called susceptor package, in which an extremely thin metalized film on a PET film is heated by the microwaves to temperatures sufficient to crisp or brown pizza or pie crusts, or to pop pop-com. The food technology differences between microwave and conventional heating are manifested by differences in development of food flavor and aroma and of food texture and appearance. Thus, modified recipes and special "microwave-adapted" food ingredients have been developed by the industry to overcome at least in part some of the quality problems of microwave-heated foods. This very substantial development of foods, packaging and ingredients for microwave heating has given an increased general knowledge about microwave heating in the industry.

Increased acquired dyschromatopsia among solvent-exposed workers: an epidemiology study on 249 employees of an aluminum-foil printing factory.

To analyze the effects on color vision of chronic exposure to mixtures of solvents including ethyl acetate, ethanol, and ketones among the workers of a large factory specializing in the manufacture of photoengraved aluminum packaging. We analyzed a group of 129 subjects who had been exposed to solvents for more than 3 years (mean age 40 years, range 25 59 years) and a nonexposed group of 120 subjects (mean age 41 years, range 21-57 years). The two groups had a similar length of service (17 and 19 years on average, respectively). The exposed subjects consumed more tobacco and alcohol than the nonexposed workers. The study involved administration of the Lanthony D-15 desaturated test. The subjects were classified as having or not having dyschromatopsia on the basis of Lanthony's criteria and the chromatic confusion index (CCI) was calculated according to Bowman's method. After observation of the work stations and analysis of an occupational questionnaire the findings were used to construct a cumulative exposure index covering the whole of each subject's working life. Air samples were taken at each work station and in each production sector to determine current exposure. The average cumulative exposure index was 194 (median 174, range 27-513). The average hygienic effect index (according to ACGIH recommendations), regularly used for atmospheres containing mixtures of products, varied between 12% and 27% of the occupational limit values permitted under French legislation. As regards color vision, 23% of the exposed group had dyschromatopsia, as did 13% of the nonexposed group, with the odds ratio (OR) adjusted for age and consumption of tobacco and alcohol being 1.99 (1.02, 3.89). The analysis of the dose-response relationship according to the cumulative exposure index showed an OR of 1.59 for the lowly exposed group (index < 174) and an OR of 2.40 for the highly exposed group (index > 174) as compared with the nonexposed group. Subjects with complex color vision loss (n=23) had a significantly higher cumulative exposure index than those with blue-yellow loss (n=23; 232 versus 155; P=0.04). The CCI was on average higher in the exposed group, but the difference between the two groups was not significant. The results of this study are in favor of an increased risk for impairment of chromatic discrimination among workers exposed to mixtures of solvents including mainly ethyl acetate, ethanol, and ketones.

Analysis of image retention in alternating-current thin-film electro- luminescent devices

Image retention can limit the upper operational frequency of ZnS-based alternating-current thin-®lm electro-luminescent (ACTFEL) devices. We studied the impact of indium-tin-oxide (ITO) electrodes pro®le, ZnS deposition conditions, the moisture content of the source material, and the drive conditions on image retention. Layer-by-layer etching and scanning electron microscopy (SEM) crosssectioning techniques were used for the investigation of this phenomenon. The failure was found to start at the column electrode edges of the pixel. Some peculiarities of the image-retention phenomenon are discussed, on the basis of an equivalent electrical scheme of the device and via crystalline properties of the active layer. The conditions for producing displays with a reduced occurrence of image retention are also discussed. ZnS:Mn-based alternating-current thin-®lm electroluminescent devices (ACTFEL) are being widely applied as high-contrast, lightweight, and rugged displays. Additional signi®cant advantages of these devices are their wide viewing angle, suf®ciently low power consumption, the capability to operate in wide temperature ranges, long life, and potentially high legibility in almost all ambient light conditions [1]. Many reports exist in the literature on the growth techniques of ACTFEL devices and the different ways to improve the ef®ciency of the structure [2, 3]. Much less attention has been paid to the appearance of destructive defects and aging phenomena, such as image retention or differential aging, which limit the operating potential of the device and ultimately hold back the exploitation of the displays. The available information is limited mostly by studies on domain electro-luminescence [4], localized destructive breakdown phenomenon [5], and the effect of moisture presence on some characteristics of the devices [6]. The appearance of the differential aging is usually explained by improper driving methods [7]. In this letter, we concentrate on the failure analysis of ZnS:Mn based ACTFEL devices, and present some important results that expand the understanding of image retention in ACTFEL devices. The typical ACTFEL structure, consisting of the glass substrate, indium-tin-oxide patterned layer, 6000 AE ZnS:Mn active layer sandwiched between two dielectrics, back aluminum electrode and packaging oxide layer, was used for this study. The dielectrics are typically yttrium oxide (Y2O3), aluminum oxide (Al2O3), and silicon oxi-nitride (SiON). The in uence of growth conditions, such as growth rate and substrate temperature Tsub, as well as the ITO shoulders pro®le and ZnS moisture content, were analyzed to clarify the origin of image retention. Before environmental and electrical testing, each structure was stabilized by a burn-in procedure. The optical and SEM studies of cross-sectioned and layer-by-layer etched samples were used as basic failure and structural analysis techniques in this series of experiments. The layer-by-layer etching technique was used to clarify the position of the damage region in the stack. All reactants were properly prepared to attack only each individual layer, without touching the adjacent one. The image retention can be described as undesirable and unrecoverable changes in driven areas of the device, leading to the appearance of the remaining image in non-energized displays (Fig. 1). It was found that the image retention can be brought on by aggressive drive conditions, such as high voltage (V . 180 V for device with threshold voltage 130 V), square wave-form pulse, and=or high frequency (.1 kHz). The ®rst two drive parameters result in the current overshooting at the onset of the pulse. The high frequency of the addressing signal leads to additional stress on the insulator= semiconductor interfaces (ISI), as well as extra heat energy release. Fig. 2a shows the typical ACTFEL ITO electrode pro®le. We suggest that in the case of a steep pro®le, electrode edges are too sharp to provide a uniform thickness distribution of the phosphor layer. As a result, the ZnS layer becomes thinner along the column edges. This results in a higher electric ®eld

Oxytocin and desamino-oxytocin tablets are not stable under simulated tropical conditions.

This study is part of a programme on reduction of postpartum haemorrhage. Buccal oxytocin and desamino-oxytocin administration with a favourable effect on both blood loss and maternal morbidity and mortality were regarded as possible treatments for use in tropical countries. The stability of buccal oxytocin and desamino-oxytocin under tropical conditions was unknown and therefore tested in this study. The 'experimental shelf lives' of buccal oxytocin and desamino-oxytocin were examined by exposing the tablets to seven artificially controlled conditions. Samples were analysed by high performance liquid chromatography to determine the content of oxytocin and desamino-oxytocin at nine different times during the period of 1 year. Oxytocin and desamino-oxytocin are fairly stable under refrigeration. Instability for both drugs was detectable after 20 weeks' storage under humid conditions, independent of temperature. Desamino-oxytocin is more sensitive to light exposure; its concentration declines to 55.6% of the stated amount after 1 year of exposure to light compared to 85% in the case of oxytocin. Oxytocin packaged as supplied by the manufacturer were stable for 21 weeks when exposed to simulated humid (75% relative humidity) conditions. At 40 degrees C and 25% relative humidity there is no difference in stability between tablets in sealed aluminium packs as supplied by the manufacturer and unpackaged tablets. Tropical conditions make oxytocin and desamino-oxytocin tablets unstable, with humidity as the most adverse factor. The oxytocin tablets were partially protected from the harmful effect of humidity by sealed aluminium package.

Performance and analysis of an aluminium nitride isolation resistor

An essential requirement of optimised microwave resistor operation is good thermal loss. In this application the thermal conductivity of the ceramic substrate base is as important as its complex permittivity. A good thermally conducting aluminium nitride resistor has been constructed for beamformer isolation purposes in corporate feed networks. Its microwave performance has been measured and found to be in good agreement with that of a conventional alumina package. An efficient and flexible quasi-static finite-element solver is also developed to model this class of structure. Numerical calculations accurately predict impedance measurements for both types of resistor. Stripline power divider measurements are included for completeness. >

Utilisation de l’impédancemétrie dans l’industrie de l’emballage

The short term prediction of the long term behavior of packaging systems is one of the main concern of the packaging world. The electrochemical impedance spectroscopy is a powerful tool to achieve such a goal. Corrosion rates of metal and delamination of organic coatings could be evaluated in real media. It is possible to quantify such intrinsic parameters of the organic protection like the thicknesses of varnishes and surface treatment layers, hydration level of natural oxide layer on aluminium thin foils. Examples concerning both steel and aluminium packaging are given.

Capacitive layers based on lead magnesium niobate buried in a multilayer substrate

Abstract 0·95PbMg 1/3 Nb 2/3 O 3 -0·05PbTiO 3 -0·03PbO green sheets were buried in a low firing alumina package using screen-printed silver electrodes. Capacitances of 30 nF/cm 2 with a loss tangent of 6% were obtained after co-firing at 860°C. The interaction mechanisms between the different materials were studied.

Paper Versus Polystyrene: A Complex Choice

As today's public and governments become more environmentally conscious we are increasingly concerned about the environmental component of product and service options available in our affluent society. Our choices are often made instinctively, from necessity, since a detailed analysis of the relative environmental merits of using canned versus fresh versus frozen foods, or glass versus paper versus steel versus aluminum packaging would simply be too time consuming for each purchase. If, however, the environmental merit question is restricted to a small enough purchase sector it is possible to conduct a complete analysis of relative merit from the initial resource through the manufacturing stages, use attributes, and recycle options through to final use or disposal of the item. Many environmentally appropriate choices of products can only be made after such an analysis. An outline of one such analysis, that of paper versus polystyrene foam as the material of construction for hot drink containers in fast food or other single use applications, is given here.

A New Laser Hermetic Sealing Technique for Aluminum Package

A new laser hermetic sealing technique which combines nickel plating with laser welding has been developed for aluminum packages. Laser welding has proved to be the most promising hermetic sealing technique for the aluminum packages. However, laser welding of the package has been difficult because of aluminum's tendency to suffer centerline cracks in the weld zone. Nickel was added in the weld zone by laser welding nickel-plated aluminum to strengthen the weld metal and prevent centerline cracks. With this aim, the optimum plating method and plating thickness were investigated. Consequently, electroless Ni-1wt%B, 5 µm in thickness was found to be best suited to the new technique, because the laser weld zone of the package exhibits a high joint strength almost equal to the tensile strength of the parent metal, and a package leakage of less than 10-9atm · cm3/s. The reliability of the hermetically sealed package was tested in accordance with MIL-STD-202F. It was confirmed that the new technique is suitable for the aluminum package for use in space, in the stratosphere and in salt-laden air.

Spectrophotometric determination of aluminum(III) using the color reaction between o-hydroxyhydroquinonephthalein and aluminum(III) in the presence of a combination of surfactants, and its application.

The color reaction between o-hydroxyhydroquinonephthalein (Qnph) and aluminum (III) was examined in the presence of various surfactants alone or in combination (cationic, anionic, nonionic and amphoteric surfactants) in weakly acidic media. A simple, rapid and sensitive spectrophotometric determination of aluminum (III) (0-2.0 μg of aluminum (III) in a final volume of 10 ml, at 555 nm) was developed by using the Qnph-aluminum (III) complex in a mixed micelle system of zephiramine (tetradecyldimethylbenzylammonium chloride) as a cationic surfactant and Brij 35 (poly (oxyethylene) dodecylether) as a nonionic surfactant. This proposed method (apparent molar absorptivity of 2.1×105 l·mol-1·cm-1) showed good reproducibility, and the influence of foreign ions was reduced to 1/4-1/10 of that in the previous method with Qnph alone in weakly basic media. The method was used for the determination of aluminum (III) in pharmaceutical preparations (aspirin aluminum). Further, since aluminum may leach out of aluminum packaging of the kind widely used for instant foods, this proposed method was applied to the assay of aluminum (III) in biological specimens (calf serum and human urine), and in leaching solution used on aluminum foil. The recovery was good, and it was found that the leaching solution contained significant amounts of aluminum (III).

Nursing attitudes toward oral liquid unit dose packaging

Nurses' attitudes toward three types of oral liquid unit dose packages--glass, plastic and aluminum--were determined. Thirty nurses who previously had not used unit dose packaging on their units were asked to evaluate the three types of packaging. The nurses preferred both aluminum and plastic over the glass containers; there was no significant difference in attitude toward the plastic and aluminum packages.

豚精液の凍結保存に関する研究

It was reported3, 4, 6) that boar spermatozoa were very sensitive to glycerol, so that glycerol should be used at low level as the freeze protective agent of boar semen. In the previous report2), it was suggested that rapid freezing and rapid thawing were necessary conditions when glycerol level was low. However, it is difficult to thaw the large volume of frozen semen rapidly. To solve this problem, aluminum which has good thermal conductivity was tried as a material of packaging container for freezing boar semen.Schematic representation of the aluminum foil and packaging container was presented in Figure 1. The package was stable against freezing and thawing process. Semen was frozen in the shape of thin plate, hence rapid thawing was expected ecause of its large surface area as well as the good thermal conductivity of aluminum.Semen was diluted with honey-yolk diluent1). Frozen semen was thawed at 38°C through the three experiments.In experiment 1, effects of aluminum packaging container on post thawing motility were examined comparing with glass ampule and pellet (Table 1). The samples (Al-package and glass ampule) were frozen with Linde BF-3R biological freezer. The post thawing motility of spermatozoa frozen in the aluminum package was superior to the glass ampule and as good as the pellet.In experiment 2, different freezing methods were compared (Table 2).The best result was obtained in the samples frozen by placing the aluminum package on horizontal dry ice.In experiment 3, the influences of semen volume in aluminum package on post thawing motility were examined (Table 3). The motility decreased as the volume of semen was increased.From these data it is concluded that aluminum package is available for the container of freezing boar semen.

豚精液の凍結保存に関する研究

It was reported3, 4, 6) that boar spermatozoa were very sensitive to glycerol, so that glycerol should be used at low level as the freeze protective agent of boar semen. In the previous report2), it was suggested that rapid freezing and rapid thawing were necessary conditions when glycerol level was low. However, it is difficult to thaw the large volume of frozen semen rapidly. To solve this problem, aluminum which has good thermal conductivity was tried as a material of packaging container for freezing boar semen.Schematic representation of the aluminum foil and packaging container was presented in Figure 1. The package was stable against freezing and thawing process. Semen was frozen in the shape of thin plate, hence rapid thawing was expected ecause of its large surface area as well as the good thermal conductivity of aluminum.Semen was diluted with honey-yolk diluent1). Frozen semen was thawed at 38°C through the three experiments.In experiment 1, effects of aluminum packaging container on post thawing motility were examined comparing with glass ampule and pellet (Table 1). The samples (Al-package and glass ampule) were frozen with Linde BF-3R biological freezer. The post thawing motility of spermatozoa frozen in the aluminum package was superior to the glass ampule and as good as the pellet.In experiment 2, different freezing methods were compared (Table 2).The best result was obtained in the samples frozen by placing the aluminum package on horizontal dry ice.In experiment 3, the influences of semen volume in aluminum package on post thawing motility were examined (Table 3). The motility decreased as the volume of semen was increased.From these data it is concluded that aluminum package is available for the container of freezing boar semen.