ES2390854T3 - Thermoformable support products and heating means thereof - Google Patents

Abstract

A packaged product comprising a product to be heated and an absorbent material loaded with water (5) wherein said absorbent material (5) is adapted to allow the microwave energy to sense and heat the water contained in the absorbent material charged with water (5) ), and the product to be heated and the absorbent material (5) are arranged adjacent to each other but are separated by a water-impermeable barrier, transparent to microwaves (6; 7, 8; 9) characterized in that the product to be heated comprises a product body support or a member of the polymeric thermoformable body.

Description

Thermoformable support products and heating means thereof

This invention relates to the products and their packages which can be heated by microwave energy. More particularly, this invention relates to thermoplastic polymeric products used to support portions of the body and to the methods for their use. Such products include slats, molds and clamps to support members of the animal's body, for example, the trunk and / or neck of an animal's body. In the present, such products are thermoformable and can be heated to tolerable temperatures for the skin and molded around the body portion to be treated. In the present description, these thermoformable products will generally be referred to as "slats" or "splinting products".

Background

The tablets usually comprise a layer or substrate of a substantially rigid thermoplastic polymeric material such as a polycaprolactone. The polymeric substrate can carry a layer of a filler material on its body-oriented surface.

In use, the splint is heated until it is flexible enough to wrap it around and shape it according to the shape of the body portion to be treated. Then, the tablet is allowed to cool and "set."

The heating of the splint is conventionally carried out by immersion in a hot water bath. However, there are several disadvantages to this method. First, there is a danger of burning the technician and the patient with hot water. Second, if the filling material is attached to the polymeric substrate, it will get wet and, in the end, will be uncomfortable for the user until it dries completely. Since the landfill is likely to retain water, the risk of burning the patient will increase. A third disadvantage is that the provision of facilities for housing the water bath and its associated heating increases the cost of the treatment and limits the availability of the treatment to specific situations. The use of water baths further increases the likelihood that the splinting product will come into contact with risks of infection such as bacteria, particularly if the water is not renewed frequently.

Attempts at "dry heating" of the tablet, which include the use of conventional microwave devices, have been largely unsuccessful because it has been difficult to warm the product evenly in a safe manner without creating hot spots which could burn the patient.

Conventional microwave ovens that are used for heating food products operate at a frequency of 2.45 GHz since this is the optimum frequency to excite the dipole molecules of water contained in the edible material, between zero and 100 ° C . The polymeric substrate of the tablet will contain little water, if any, and may contain dipole molecules that have a relative permissiveness (E) different from that of water and therefore cannot be sufficiently heated in a microwave oven operating at 2.45 GHz. The geometry of the tablet substrate can be very complex, especially if it is composed at least partially of areas that have a network-like conformation and direct heating with microwave energy can cause the tablet areas to overheat due to to the known "Overheating phenomenon at the edges", which results in hot spots and the consequent burn of the patient.

The prior art relates to edible materials and is typified by the following:

In the description of US Patent No. 2001/043971, which is considered as the closest prior art, describes suitable microwave food containers, such as tamales, and a method related to microwave steam heating or cooking of such foods. The food package includes a non-ventilated, sealed, stretchable plastic bag that completely covers the food product and a moisture pad which is placed on the food product. The pad serves to protect the food product from direct microwave radiation, and to provide a source of steam generated by the absorption of the waves in the water of the pad.

In the description of US Patent No. 2007/029314 describes a food suitable for pre-packaged microwaves that has a steam emission source integrated into the package that allows the preparation of the food product in a wide range of microwave ovens. The food product is placed in a container. The steam source is placed in porous communication with the food product inside the package. When the container is heated, steam covers the food product. Steam has a positive effect on cooking performance and cooking time. The steam emitting source can be made of an absorbent material or a gel. The food product can be a semi-finished product, pellets, or other microwave food or snack product.

Summary of the invention

The present invention seeks to provide the means for heating thermoplastic polymer tablets, including tablets that carry a filler layer for safe and uniform contact with the skin, using a heating apparatus which does not suffer from the disadvantages associated with baths of hot water from the previous matter.

According to the present invention, a packaged product is provided comprising a product to be heated and a water-loaded absorbent material wherein said absorbent material is adapted to allow microwave energy to enter and heat the water contained in the charged absorbent material. of water; and the product to be heated and the absorbent material are arranged adjacent to each other but are separated by a water-impermeable barrier, transparent to microwaves.

An advantage of the present invention described herein is that the transfer of energy to a thermoplastic tablet is not based solely on the principle of heat energy in the form of hot steam and then condensation on the surface of the object being heated as in prior art In fact, in the present invention it is preferred that any steam generated remains within the sealed bag containing the absorbent material charged with water throughout the heating process. It has been found that the presence of an absorbent pad containing water in the proximity of the substrate product to be heated, attenuates microwave irradiation during heating and favorably changes the permissiveness values of the thermoplastic material of the nearby board and reduces the so-called "Overheating phenomenon at the edges" common in food warming. This results in greater uniformity in the heating of the substrate product and the reduction of "hot spots".

In the absence of the water-containing absorbent pad, the applicant found that the substrate that is heated suffers from severe "hot spots" and begins to burn and smell after a short time when exposed to microwave irradiation.

Therefore, according to the invention, the absorbent material charged with water acts as an attenuator and favorably regulates microwaves to prevent burning. Thus, an even more uniform distribution of heat is achieved throughout the entire product to be heated, thus avoiding "hot spots." In addition to this, cold spots are avoided through the parallel effect of heat that is transferred through the barrier or bag containing the absorbent material in those affected areas.

The utility of using the packaged product of the invention to heat substrates such as thermoplastic slats is that the substrate product can be conveniently heated easily, safely, and quickly in a microwave oven which are a familiar way of heating to Many people in developed countries.

The particularities that characterize the invention are set forth in the appended claims.

In one aspect, the product to be heated may comprise a body support product or a support product of a thermoformable polymeric body member while in another aspect, the product to be heated may comprise an edible material.

Thus, the present invention provides, in one aspect, a packaged product comprising a product to be heated in combination with a water-laden absorbent material wherein

•

said absorbent material is adapted to allow microwave energy to enter and heat the water contained in the absorbent material charged with water, and

•

the product and the absorbent material are arranged adjacent to each other but are separated by a water impermeable barrier, transparent to microwaves.

The water-laden absorbent material may be sealed in a first water-impermeable, microwave-transparent container.

In one embodiment, the invention provides a packaged product comprising a thermoformable tablet in combination with an absorbent material loaded with water sealed in a water-impermeable, microwave-transparent container where

•

said absorbent material is adapted to allow microwave energy to enter and heat the water contained in the absorbent material charged with water, and

•

the splint and the absorbent material are arranged adjacent to each other but are separated by a water-impermeable barrier, transparent to microwaves.

The water-laden absorbent material can be sealed in a second water-impermeable, microwave-transparent container, particularly in the form of a bag.

As used herein, absorbent material charged with water alone or sealed in a second container will be referred to as a "heating pad."

Throughout this description, the terms "transparent to microwaves" and "transparent to microwave energy" mean "non-reactive to microwave energy". Materials that are transparent to microwaves (ie non-reactive to microwave energy) are characterized by having a structure that lacks dipole molecules. Suitably, the microwave transparent barrier, container or bag material may comprise polyethylene. Therefore, the transparent microwave barrier, container or bag can be produced from "food grade" polyethylene.

Brief description of the drawings

Although the present invention can be used to heat many products, including edible materials, it is particularly useful for thermoformable tablets and is described and illustrated with particular reference to said products through the examples.

In the drawings:

Figure 1 schematically illustrates the general arrangement of the components of the products of the invention in one embodiment;

Figures 2, 3 and 4 schematically illustrate several modalities that have variations of the particular dispositions of the product, the heating pad and the package.

Detailed description

The thermoplastic polymers used in the present invention must be reactive to microwave energy, that is, they must contain dipole molecules. Polymers that are useful in the present invention include those based on caprolactone molecules. The polymeric material of the tablet can comprise caprolactone homopolymers or combinations of these polymers, either alone or in admixture with fillers such as fibrous lignin materials. Preferred splinting products for use in the present invention are those described in the published patent descriptions of applicant no. US 2008154164 and WO 2008041215, and among others describe a thermoformable polymeric product to support the body comprising a member formed of a composite material that includes a polycaprolactone and a lignocellulosic additive, and said composite material is formed at a formation temperature greater than ambient temperature, which is substantially rigid at room temperature and where the member has one or more through openings where at least part of these are arranged so that the flexural strength of the member in a first direction is greater than in a second address.

The most preferred splinting products are multicomponent products comprising a thermoplastic polymeric substrate that carries a skin contact filler layer on a substrate surface. Such multi-component splinting products are described in the patent descriptions published by the aforementioned applicant.

With reference to Figure 1, the thermoformable splinter (also referred to herein as splinting product) (1) comprises the thermoplastic substrate (2) attached to a layer that contacts the skin (3) which can be rightly a material spacer fabric The splint (1) is arranged immediately adjacent to the heating pad (4) which comprises a water-laden absorbent material (5) sealed in a water impermeable bag, transparent to microwaves, and aptly conductive heat (6).

Successfully, as shown in Figure 2, the board (1) and the heating pad (4) are packaged in an outer container (7) formed of a water impermeable material, transparent to microwave energy. The outer container (7) can be of rigid construction or, more preferably, is in the form of a flexible bag.

Therefore, according to this embodiment of the invention, the board (1) and the heating pad (4) are contained in a single outer container (7).

Alternatively, as shown in Figures 3 and 4, the board (1) and the absorbent material loaded with water (5) may be contained in separate bags or compartments. Preferably, a vacuum is created in each compartment or bag to ensure better contact and heat transmission.

Therefore, as shown in Figure 3, the bag 7 is provided with two compartments, separated by a membrane or partition (8) impermeable to water, transparent to microwaves, wherein the first compartment contains the absorbent material charged with water (5) and the second compartment contains the splinting product (1).

In the embodiment shown in Figure 4, the splint (splinting product) (1) is contained in a separate inner bag (9) of a water-impermeable material, transparent to microwaves. Heating pad

or absorbent material loaded with water (5) together with the splint (2) contained in the inner bag (9) are then included in the outer bag (7). Preferably, the board (1) is sealed in a vacuum inside the inner bag (9). The bags containing the slats are preferably made of a polyethylene and nylon laminate to ensure that the vacuum is maintained in the package for a long period of time, for example, at least 1 year. More preferably, the inner bags (9) are sealed by welding and made of 301 nylon / 501 low density polyethylene (LDPE) laminate.

The compartments or bags can also be provided with pressure relief means (10, 11). For example, a fragile rupture seal (10) can be provided in the bag containing only the absorbent material loaded with water (5) to vent excess steam accumulation inside the container and prevent distortion or contamination of the splinting product (one). Pressure discharge means (11) may be provided in the bag or compartment containing the splinting product (1) to allow the atmosphere inside the bag or compartment to be reduced, causing deformation of the bag or compartment walls and allowing the splinting product (1) and the absorbent material (5) to be more closely adjacent.

The compartments or bags containing the tablet (1) are also provided with means to allow rapid removal of the heated tablet. The pressure removal and release means, although operated independently, can be formed in a unit device.

The board (1) and the heating pad (4; 5) should be arranged to be located as closely adjacent to each other as possible if both components are packaged together or placed separately in the microwave heater. We have found that the presence of the heating pad (4; 5) in close proximity to the product to be heated, (for example, where the product comprises a thermoplastic tablet) will cause the microwave irradiation to attenuate during heating. This effectively favors changes in the permissiveness values of the adjacent product and decreases the so-called "edge heating phenomenon", a problem that is normally found in food heating. The geometry of the thermoplastic slats (1) is complex. For example, clamps and clamps such as those described in the aforementioned patent publications Nos. US2008154164 and WO2008041215 have areas in the form of open networks and other areas configured as ribs similar to ribs. The non-uniformity of the general shape or the cross-sectional area and the variations in the patterns of distribution of microwave radiation in microwave ovens alter the permissiveness of the product material in different places. Therefore, when directly heated, energy is absorbed more quickly in certain areas particularly where there is more abundant microwave radiation, and therefore the polymer begins to melt prematurely in these areas while other areas are slower to heat up. In these areas the polymer molecules begin to oscillate at a higher frequency (compared to the oscillation frequency when the polymer is in the solid state) and the temperature in these local areas increases dramatically, causing hot spots. Other areas of the product material may exhibit cold spots. The absorbent material loaded with water (5) adjacent but not touching the product to be heated, attenuates microwave irradiation during heating and favorably changes the permissive values of the adjacent product thus improving heat distribution across the product area adjacent heating, resulting in a more uniform heat distribution and a reduced tendency for the occurrence of hot and cold spots.

The heating phenomena at the edge can be further attenuated if the heating pad (4; 5) is placed in close proximity to the filling layer that contacts the skin of a multi-component splinting product (1). The uniform distribution of heat will reduce the occurrence of hot spots and will allow to set higher microwave energies to use and / or shorten the time for heating. The uniform distribution of heat also prevents the occurrence of "cold spots" since the water evaporated upon contact and condensation on the material areas of the bag (6, 7, 9 or partition (8) adjacent to any cold point on the substrate of the tablet polymer will heat such areas.

The water absorbing material (5) may comprise any known material that will absorb and retain water. Such materials may comprise a hydrogel such as those based on celluloses or be composed, at least in part, of hydrophilic fibers such as those known as superabsorbent polyolefins filaments. Preferably, the water absorbing material (5) comprises nonwoven fibers of an acrylic polymer or filaments. The water absorbing material (5) comprises a material that allows microwave heating of the absorbed water contained in the water absorbing material (5).

Preferably, the water absorbing material (5) contains and retains sufficient absorbed water so that there is no free water outside the water absorbing material (5). This ensures a uniform distribution of water over the cross-sectional area of the product (1) that is heated by microwave energy and therefore ensures uniform heat absorption and dissipation in the underlying substrate. Successfully, the absorbent material contains water in an amount in a range of 0.01 to 0.15 ml.cm2. Typically, the absorbent material (5) will contain approximately 0.05 ml of water per cm2 of absorbent material.

The absorbent material loaded with water (5) can be placed adjacent to the filler material that contacts the body (3) which can be part of the board (1) to ensure not only adequate and uniform heating of the thermoformable polymer (2) but also to control the amount of heat applied to the filler layer that contacts the body (3) of the splint (1). Since the permissiveness of the filler (3) will be different from that of the polymeric substrate (2) the layer of the filler that contacts the body (3) does not heat up to the same temperature as that of the substrate (2).

Depending on the power of the microwave energy used and other characteristics of the energy source, the adjustment time must be calibrated to allow heating of the thermoplastic substrate (2) at a temperature such that it becomes sufficiently flexible to roll it or form it around the body portion to be supported and still not high enough to cause discomfort or burning of the skin. For a domestic microwave oven that generates energy at a frequency of 2.54GHz we have found, for example, that a time of approximately 3 minutes is required to heat the polymer substrate (2) of a lower arm of the board to approximately 60 ° C.

The invention will be illustrated by way of example with reference to the following Example:

Example

A heating pad of 50ml of water was formed in a 125 micron PE bag containing an absorbent pad measuring 300mm x 330mm and the bag was sealed using a heat sealer. The absorbent pad was made of superabsorbent fibers of commercial grade biocomponent polyolefins.

The heating pad was placed inside a commercial microwave oven (Sharp R21AT model), at a rate of 1000 watts at 100% power setting and a thermoplastic substrate (for example a space for the lower arm of the board) that had approximately the same dimensions as the heating pad was placed on the heating pad.

The oven power was adjusted for a 60% setting (equated to 600 watts) and turned on for 3 minutes.

After 3 minutes the thermoplastic tablet was removed and found to be fully activated. The product was soft and flexible and there was no evidence of overheating, hot spots, burns or smell.

The packaged products of the invention will include any product or material to be heated to temperatures generally within the boiling range of the water contained in the water absorbing material. Such products or materials to be heated may include edible materials and thermoplastic materials in addition to the thermoformable tablets.

The packaged products of the invention are ideally suited for microwave heating but can be heated in conventional water baths as they are kept separate from the heating environment.

It will be clearly understood that the present invention is not limited to the details described herein that are given by way of example only.

Claims (14)

one.

A packaged product comprising a product to be heated and a water-loaded absorbent material (5) wherein said absorbent material (5) is adapted to allow microwave energy to enter and heat the water contained in the water-loaded absorbent material (5), and the product to be heated and the absorbent material (5) are arranged adjacent to each other but are separated by a water-impermeable barrier, transparent to microwaves (6; 7, 8; 9) characterized in that the product for being heated comprises a support product of the body or of a member of the thermoformable polymeric body.

2.

A packaged product as claimed in claim 1 wherein the packaged product comprises a first sealable, water impermeable and microwave transparent container (7).

3.

A packaged product as claimed in claim 2 wherein the microwave-impermeable water impermeable barrier comprises the first microwave-impermeable water impermeable container.

Four.

A packaged product as claimed in claim 3 wherein the water-laden absorbent material (5) is sealed in the first water impermeable container (6; 7).

5.

A packaged product as claimed in claim 2 wherein the product (1) to be heated and the absorbent material (5) are sealed within the first transparent waterproof container (7).

6.

A packaged product as claimed in any of the preceding claims, wherein one of the product (1) to be heated and the absorbent material (5) is contained in a second container (8 (7); 9) formed of a material Microwave transparent, waterproof to separate it from the other product to be heated and from the absorbent material (5).

7.

A packaged product as claimed in Claim 6 wherein the second container (9) is fully contained by the first container (7).

8.

A packaged product as claimed in Claim 6 wherein said first container (7) is separated by a partition (8) in two compartments, one of said compartments defines said second container.

9.

A packaged product as claimed in any of the preceding claims, wherein the water that is loaded from the absorbent material (5) is not more than the amount to saturate the material (5); and optionally, wherein the water absorbing material (5) is selected from the group comprising: hydrogels and hydrophilic polymeric fibers or filaments.

10.

A packaged product as claimed in any of the preceding claims wherein the water that is loaded from the absorbent material (5) is from 0.01 to 0.15 ml.cm2; optionally, wherein the water that is loaded from the absorbent material (5) is approximately 0.05 ml.cm2.

eleven.

A packaged product as claimed in any of the preceding claims, wherein said first container (7) is provided with means (10) to allow the discharge of gas pressure into said first container (7).

12.

A packaged product as claimed in claims 6 to 11 wherein said second container

(9) is provided with means (11) to allow the discharge of gas pressure into said second container (9).

13.

A packaged product as claimed in claim 1, wherein the body support product or a member of the thermoformable polymeric body (1) comprises a layer of filler material that contacts the skin (3); and optionally, the filler layer (3) is disposed adjacent to the absorbent material (5).

14.

A packaged product as claimed in claim 13, wherein the thermoformable polymeric body support product comprises a member formed of a composite material that includes a polycaprolactone and a lignocellulosic additive, said composite material is formable at a forming temperature greater than room temperature and is substantially rigid at room temperature and where the member has one or more through openings where at least part of these are disposed of

so that the flexural strength of the member in a first direction is greater than in a second direction.