WO2018178462A1

WO2018178462A1 - Mineral composition and use thereof as an additive for the production of cardboard boxes, packaging and/or containers

Info

Publication number: WO2018178462A1
Application number: PCT/ES2018/070242
Authority: WO
Inventors: Juan Carlos LLOBREGAT AGUSTÍ; José Antonio SIVERA MARZÁ
Original assignee: Primlab Global, Sl
Priority date: 2017-03-31
Filing date: 2018-03-26
Publication date: 2018-10-04
Also published as: ES2690547B1; ES2690547A1

Abstract

The invention relates to a mineral composition of igneous rock, comprising a mixture of magnesium (between 1 and 25%), iron (between 1 and 23%), calcium oxide (between 1 and 25%), aluminium (between 0.1 and 11%) and silicon dioxide (between 16 and 75%), with a particle thickness between 50 nm and 1000 µm, which mixture is added in a percentage of 1 to 15% by weight in a process of manufacturing a paste of cellulose and polymer materials for the production of all types of packaging, containers and cardboard boxes for food, electronic and technological products, cellulose bags, hygiene products, optical products, etc., with functions of humidity absorption (stabiliser), fire resistance (limited contribution to fire) and thermal insulation, as well as antimicrobial function to preserve products in optimal conditions.

Description

DESCRIPTION

Mineral composition and its use as an additive for the manufacture of cardboard furniture, packaging and / or packaging.

OBJECT OF THE INVENTION

The present invention is indicated as an additive for the manufacture of packaging and / or containers that allows it to function as a thermal insulator, anti-humidity (stabilizing action), flame retardant (limited fire contribution) and antimicrobial. Thus the packaging, packaging (paper, cardboard and polymeric materials) and cardboard furniture made of our mineral composition derived from igneous stones, with properties that keep the products in an optimal state of humidity, temperature, flame retardant and inhibiting microbial growth, preserving the qualities of the products, minimizing the environmental impact in addition to its easy recycling.

The mineral composition is added in the mixing process in the manufacture of cellulose pulp or polymeric materials with a specific percentage (between 1% to 15% by weight), it is the most economical and ecological solution in the market .

The present invention is intended for the sectors of packaging, packaging (cardboard or plastics) and cardboard furniture.

BACKGROUND OF THE INVENTION

It is well known that the containers and packaging used today generate a great controversy at the level of environmental impact, due to the overexploitation of non-biodegradable or renewable resources. An increasing number of consumers require that packaging and packaging be recyclable and safer. Recyclable packaging is one of the public's priorities when buying products, as it is seen as a protective factor for the environment.

Consumers and legislators are increasingly aware of packaging. This trend is particularly noticeable in Europe. In Holland, for example, a tax is applied to packaging manufacturers according to the average C0 ₂ emissions of the materials they use - from 36 to 57 euro cents per kilogram of aluminum packaging, 6 cents per carton.

Cardboard is a material that is manufactured from several layers of superimposed paper. The cardboard is recycled in the blue container and in this way it can be used again. But it can also be used to create furniture. Nowadays, consumers buy all kinds of cardboard furniture for its originality and its cheaper cost.

There are four forms of water contamination in a closed container or package: 1) water vapor in the air inside the package;

2) water vapor absorbed by the materials inside the package;

3) water vapor on the walls of the package; Y

4) the water vapor that enters through the package. Currently, there are a wide variety of desiccant or absorbent products on the market, such as: montmorillonite clay, silica gel, molecular sieve or synthetic zeolite, calcium oxide (CaO), calcium sulfate (CaS0 ₄ ) etc. Among these products, the most suitable for each application should be chosen. However, due to the conservation measures of the products (temperature and relative humidity -HR) and to avoid water vapor in the form of condensation, it is necessary to keep them at an optimum level of humidity and there are no products that cover all the parameters suitable to avoid such moisture.

The most useful measure that combines temperature and RH is the dew point. The dew point is the temperature at which the water vapor content in the air exceeds saturation and the excess water is squeezed out forming water condensation. An example of condensation of air at 0 ^e C cannot maintain more than 4.84 g / m ³ of water vapor; at 40 ° C the air cannot maintain more than 50.7 g / m ³ of water vapor. An effective desiccant will absorb water vapor in the air, lowering the RH to the point that water cannot condense.

Because many products destined to the food sector need to be kept at an optimum temperature, they are usually refrigerated in industrial refrigerators. This can cause considerable deterioration of stored products, due to the increase in humidity and / or the appearance of harmful fungi (from 40% RH), such as Penicillium digitatum, fíhizopus stolonifer, Aspergillus spp. Likewise, many Bakery products and industrial bakeries are usually sold in kraft paper bags to preserve freshness and facilitate the transport of these products by the consumer, but the loss of moisture from fresh products reduces their properties. Silica gel desiccant bags, which are used for moisture absorption, are known in the market, but in addition to having high manufacturing costs, they are also known for their toxicity by the dust that creates several of their compounds, the Cobalt chloride, silica oxide, which can cause silicosis by breathing (which causes cough, fever and difficulty breathing and usually evolves into pulmonary fibrosis) and have an environmental impact, in addition to the high costs for industrial use.

EXPLANATION OF THE INVENTION

Heat and humidity are two fundamental factors for microbial growth. Currently, existing products on the market such as packaging, cellulose packaging and / or trays of polymeric materials intended to contain everyday products (eg cookie boxes, electronic packaging, medicines, fruit trays and meats etc.) none have the qualities described in the present invention. The present invention is characterized by the properties of the additive, a mineral composition in packaging, cellulose pulp containers, cardboard furniture manufacturing and polymeric materials, which make four very important properties, thermal property, fire retardant property, property anti-humidity (stabilizer), the antimicrobial property and easy recycling, respecting the environment and with a low manufacturing cost, as well as extending the product's useful life. Preferably, from homogenous igneous rocks

The main minerals of our composition are preferably from igneous rocks, sedimentary and metamorphic rocks (magnesium, iron, aluminum, calcium oxide, silicon dioxide), which are mixed in the manufacture of cellulose pulp and / or polymeric materials between percentage from 1% to 15% by weight and with a particle diameter between 50 nm and 1000 μηι.

The use of the mineral composition represents a great economic advantage for these types of packaging, containers and furniture, since by homogeneously integrating the mineral composition with cellulose pulp or polymeric materials, they make the interaction between the network of cellulose or polymeric materials and the mineral composition is uniform and regulates the humidity by the properties of the minerals of our formulation (MgFeCaOAI) ₆ S¡0 ₂ rich in Mg (between 1 and 25%), Fe (between 1 and 23%), CaO (between 1 and 25%), Al (between 0.1 and 1 1%) and Si0 ₂ (between 16 and 75%), which has a coefficient of thermal conductivity of about 0.20 W / (Km), resulting in the improvement of humidity regulation (as an absorbent, due to its nanoporous structure) inside the packaging due to chemical interactions between the mineral composition and the HR of the product. Among the polymeric materials, thermoplastics are linear polymers, which may or may not be branched, since they are not crosslinked, they are soluble polymers in some organic solvents, they are capable of being molten and are therefore recyclable. If we compare them with other types of plastics, thermoplastics are manufactured and used in very large quantities and among them the most frequent are polyethylene (PE), polypropylene (PP), polystyrene (PS), expanded polystyrene (PSE), polyvinyl chloride (PVC) etc. In fact, more than half of the total number of plastics processed corresponds to the five plastics cited.

Our mineral composition has the fire-retardant property, which applied to packaging, containers and cardboard furniture delay the consequences of product ignition, because the nature of the ingredients of our invention is derived from igneous rocks, whose chemical elements can withstand very high temperatures .

In food, one of the main problems are contamination by the emission of mycotoxins, derived from fungi (microbes). Among the most harmful are the Penicillium digitatum, fíhizopus stolonifer, Aspergillus spp, Fusarium spp etc., which grow in a high relative humidity (between 50% to 90% RH). The use of our invention counteracts the effects of moisture and heat, thereby reducing the chances of microbial growth in containers or packages primarily intended for human use.

The absorption capacity of the product with an RH between 20% and 90% ranges between 10% and 45% on its weight in water. At an ambient temperature of 22 ^e C and a RH of 40%, the absorption capacity is 20 ± 3%.

In addition, the mineral composition has the ability to regulate humidity, when the product is stored in a humid environment, the mineral composition absorbs moisture up to 50% of its weight in water. If the storage conditions of the packaged / packaged products change to a lower humidity, the mineral composition slowly releases the amount of water retained in its structure, causing the content of the stored product to maintain optimum humidity conditions. This process is due to the permeability of the porosity of the mineral compound between K <10 ^{~ 6} - 10 ^{~ 4} ms ^"1 .

PREFERRED EMBODIMENT OF THE INVENTION

The present invention relates to a composition preferably formed by mineral compositions, preferably extracted and selected from igneous rocks, (with the following mineral composition (MgFeCaOAI) ₆ S0 ₂ ) used for the production of packaging, packaging (paper , cardboard and polymeric materials), as well as cardboard furniture, with properties that keep the products in an optimal state of humidity, temperature, flame retardant protection and inhibiting microbial growth, with a percentage of our mineral compound mixed in the manufacturing process of products between 1% to 15% by weight and with a particle diameter between 50 nm and 1000 μηι. Example 1 :

As an example of said invention, mention is made of a cardboard container of approximately 200 g with 2% by weight (4 gr / U of our mineral composition) (10% Mg, 6% Fe, 10% CaO, Al at 2% and Si0 ₂ at 72%) with a particle diameter of 400 μηι of our mineral composition. This percentage is added in the manufacturing process at the wet end (in the phase - mixing tub) together with the other additives (glues, bleaching agents, fillers, fibers, etc.) following the standard industrial conditions for their manufacture. With these minerals, the products contained in said container preserve an optimum state of humidity, fire protection, inhibition of microbes and thermal insulation.

Example 2:

Another example of packaging manufacturing is kraft paper in the form of paper bags, which are used to sell the bread after being baked. 5 bags of kraft paper of 5 gr each were manufactured and our mineral composition was added (8% Mg, 8% Fe, CaO at 15%, Al at 2% and S¡0 ₂ at 67%) with a percentage of 3% by weight (150 mg / U of our mineral composition) and with a particle diameter of 200 μηι. This percentage is added in the manufacturing process at the wet end (in the phase - mixing tub) together with the other additives (glues, bleaching agents, fillers, fibers, etc.) following the standard industrial conditions for their manufacture.

A study was carried out with 10 freshly baked breads (standard industrial conditions) with a 45% RH and crispy state of the bread (it was considered very crispy to the touch, giving it a subjective assessment of 5/5), 5 loaves were introduced in bags of Kraft paper made with our mineral composition (study group) containing 3% by weight. Likewise, 5 loaves were introduced in kraft paper bags without our mineral composition (control group) to make comparisons of humidity and freshness between 12 hr and 24 hr. At 12 h it was observed in the study group that the product (bread) had a RH of 43%, averages with a trotee ^® moisture measuring device and were still crispy (4/5), compared to the control group, 41% RH and crispy (3/5) were measured. At 24 hr it was observed that the breads of the studied group had a RH of 39% and a crunchy state (2/5), compared with the control group, observing a RH of 34% and a state that could no longer be considered " Crispy "(0/5).

It was observed that the kraft bags with our mineral composition held the humidity more, compared to the control group and kept the crunchy product (bread) longer, with the bread being in the soft control group.

Example 3:

Another example of manufacturing is the use of thermoplastics that are used in trays for food products, in medicines, electrical appliances etc. As an example of thermoplastic manufacturing - polyethylene (PE), intended as a 10-gram tray for packaged meat, is added our mineral composition (15% Mg, 8% Fe, 15% CaO, Al 2 % and Si0 ₂ at 60%) with a percentage of 5% by weight (500 mg of our mineral composition) and with a particle diameter of 300 μηι.

An experiment was carried out with polyethylene (PE) trays to check the thermal property and moisture stabilization inside the tray. 5 were manufactured trays with the mineral compound and 5 without said compound.

They were packed in the 10 trays with 1 apple in each tray and all the trays were closed with transparent plastic film with an ambient temperature of 28 ^e C and an 80% RH. At 6 hours, two trays with the mineral composition and two without the mineral composition were checked, having an ambient RH of 84% and a temperature of 26 ^e C. The humidity and temperature were measured with a meter (Trotee T210), and He found that in the two trays that had the mineral compound the internal RH was 60%, while in the two trays without the mineral compound the internal RH was 79%.

At 24 h, the following six trays were analyzed (three with the mineral compound and three without the mineral compound) with an ambient temperature of 30 ^e C and an 82% RH. It was observed that the trays with the mineral compound had a RH between 57% and 59%, the other trays without the mineral compound had a RH between 78% and 80%.

In this way it was observed that the mineral compound significantly regulates the RH inside the packaging. One form of industrial application is by adding the mineral compound in the stirring process with mixing the catalyst (benzoic peroxide). Example 4:

10 biscuit-shaped cellulose tablets of 1 cm thick each were made, 5 tablets with the mineral compound (10% Mg, 6% Fe, 10% CaO, 2% Al and 72 Si0 ₂ %) at 5% by weight and a thickness of the compound of 400 μηι, with a weight of approx. of 27 gr and 5 tablets without the mineral compound with a weight approx. of 25 gr, to check the consequences of ignition of the product.

A constant flame of fire was applied for 2 min at 1600 ^e C and it was observed that the 5 tablets with the mineral compound did not burn, but only gave off smoke. The time of fire exposure to a constant flame of 5 min was increased and the result was the same, it only smoked.

A constant flame of fire was applied for 1.5 min at 1600 ^e C with the other tablets without the mineral composition. It was observed that, during this time of exposure to fire, the tablets began to burn until they consumed all the cellulose. In this way, it was observed that the mineral compound has a better behavior against fire, that is, that the material is combustible, but not flammable.

Claims

one . Mineral composition for the manufacture of packaging, packaging and cardboard furniture made of cellulose and polymeric materials whose composition comprises at least magnesium (between 1 and 25% by weight), iron (between 1 and 23%), calcium monoxide (between 1 and 25%), aluminum (between 0.1 and 1 1%) and silicon dioxide (between 16 and 75%) with a particle thickness between 50 nm and 1000 μηι.

2. Use of the composition of claim 1, for the production of packaging, containers, cardboard furniture and polymeric materials for moisture stabilization, preferably in a percentage of 1% to 15% by weight.

3. Use of the composition of claims 1, for the production of packaging, containers, cardboard furniture and thermoplastic materials for thermal insulation, preferably in a percentage of 1% to 15% by weight.

4. Use of the composition of claims 1, for the production of packaging, containers, cardboard furniture and thermoplastic materials as a flame retardant additive, preferably in a percentage of 1% to 15% by weight.

5. Use of the composition of claims 1 for the production of packaging, containers, cardboard furniture and thermoplastic materials as an anti microbial additive, preferably in a percentage of 1% to 15% by weight.