TWM513030U - Wet wound dressing - Google Patents

Description

Wet wound dressing

The present invention relates to a wet wound dressing, and more particularly to a wet wound dressing comprising a sheet of absorbent layer.

Due to the increased awareness of health care, wound care after surgery has received much attention. Therefore, various wound dressings that can avoid infection and protect wounds have been developed.

In order to further promote wound healing, it is usually mixed in the dressing substrate or coated on the surface to promote wound healing (for example: alginate, hyaluronic acid or its salt, hypoglycate, etc.), However, blending or coating requires not only an additional processing process, but these additional added active ingredients are prone to wear and loss and require frequent dressing changes (approximately 5 to 7 days), and may also be due to absorption of the active ingredient by the dressing substrate. Reducing the absorption of wound dressing by wound dressing has limited help for wound healing.

Accordingly, it is an object of the present invention to provide a wet wound dressing that covers the wound and that has both hydrophilicity that maintains the wound moist and promotes wound healing and that effectively absorbs wound exudate.

Therefore, the novel wet wound dressing comprises a sheet of absorbent layer The sheet-like absorbent layer is made of a hydrophilic polyurethane or a foam thereof, wherein the hydrophilic polyurethane reacts the first polyether polyol with the polyisocyanate, and then reacts with the second polyether polyol and hyaluronic acid. In the case of a star block polyurethane, the first polyether polyol contains at least three terminal hydroxyl groups.

The effect of the novel wet wound dressing is that the sheet-like absorbent layer can effectively promote wound healing and absorb wound exudate.

The novel content will be described in detail below: the star-like structure of the star-shaped block polyurethane allows the polyurethane to have a large specific surface area to enhance the water absorption characteristics of the wet wound dressing.

Preferably, the wet wound dressing of the present invention further comprises a backing and a release paper, the sheet-like absorbent layer being fixed to the backing, the release paper covering the sheet-like absorbent layer and the backing . The backing is for adhering to the skin surrounding the wound. In order to maintain the tack of the backing, the release paper is for tearing off prior to use.

Preferably, the hyaluronic acid has a weight average molecular weight ranging from 500,000 to 2,500,000. Hyaluronic acid having a weight average molecular weight higher than 2,500,000 is less favorable for promoting wound healing. In a specific embodiment of the invention, the hyaluronic acid has a weight average molecular weight of 1,000,000.

Preferably, the total of the first polyether polyol, the polyisocyanate, the second polyether polyol, and the hyaluronic acid is 100 mol%, and the content of the hyaluronic acid is in the range of 0.001 to 20 mol%. More preferably, the hyaluronic acid is contained in an amount ranging from 0.001 to 10 mol%.

Preferably, the polyisocyanate is an aliphatic polyisocyanate to avoid the risk of toxicity which may be selected from aromatic compounds. More preferably, the aliphatic polyisocyanate is selected from the group consisting of hexamethylene diisocyanate (HDI), methylene dicyclohexyl diisocyanate (H ₁₂ MDI), isophorone diisocyanate. (isophorone diisocyanate, IPDI) or a combination thereof. In a particular embodiment of the invention, the polyisocyanate is hexamethylene diisocyanate.

Preferably, the first polyether polyol is poly(propylene glycol) triol (PPG triol)

Preferably, the second polyether polyol is polyethylene glycol (PEG).

In a specific embodiment of the present invention, the hydrophilic polyurethane is obtained by reacting poly(propylene glycol) triol with the polyisocyanate to form a star-shaped prepolymer, and then crosslinking with polyethylene glycol and hyaluronic acid. Star-shaped block polyurethane.

Preferably, the polyethylene glycol has a weight average molecular weight ranging from 1,000 to 6,000. If the weight average molecular weight of the polyethylene glycol is less than 1,000, biotoxicity is generated via metabolism; if the weight average molecular weight of the polyethylene glycol is more than 6,000, the operation of the crosslinking reaction may be difficult due to the high viscosity, but if Adding a solvent to lower the viscosity allows the solvent to remain on the dressing and pose a risk of cytotoxicity.

Preferably, the pore of the hydrophilic polyurethane foam is a discontinuous closed pore, and the hydrophilic polyurethane foam is such that the hydrophilicity Polyurethane and a foaming component are obtained by foaming. This closed hole avoids the risk of new tissue growing into it during wound healing and reduces the damage that can be caused by removal.

More preferably, the foaming component comprises a blowing agent, water, a surfactant, a polyamine, and a catalyst. The polyamine is used to increase the mechanical strength of the hydrophilic polyurethane. More preferably, the polyamine is selected from the group consisting of 1,2-ethanediamine, 1,4-butanediamine, 1,6-hexanediamine, and three. Triethylenetetramine (TETA) or polyetheramine. The polyether amine selected from, but not limited to, produced by Huntsman JEFFAMINE ^®. The catalyst is used to catalyze the reaction of excess polyisocyanate with water to produce carbon dioxide. More preferably, the catalyst may be selected from zinc isooctylate, triethylene glycol diamine (TEDA, DABCO), dimethylcyclohexylamine (DMCHA). , dimethylethanolamine (DMEA), triethylamine (TEA), 1,8-dioxinbicyclo[5.4.0]undec-7-ene (DBU) or pentamethyldiethylenetriamine (PMDETA) ).

1‧‧‧Flake absorption layer

21‧‧‧Backing

22‧‧‧ release paper

Other features and effects of the present invention will be apparent from the following description of the drawings. FIG. 1 is a perspective view illustrating the sheet-like absorbent layer of the present invention; and FIG. 2 is a perspective view showing the present invention. The wet wound dressing of the novel embodiment 2.

Before the present invention is described in detail, it should be noted that in the following description, similar elements are denoted by the same reference numerals.

The present invention will be further described in the following examples, but it should be understood that these examples are for illustrative purposes only and are not to be construed as limiting.

<Preparation Example 1> Star-shaped hydrophilic polyurethane PU1

1 mol of PPG6000 triol (weight average molecular weight of 6,000) was mixed with 3 mol of HDI, and reacted at 80 ° C for 1 hour to obtain a star-shaped prepolymer, and then 1 mol of PEG 1000 (weight average molecular weight of 1,000) and 1.5 mol of PEG 2000 (weight average molecular weight) were added. 2,000) and 0.5 mol of hyaluronic acid (weight average molecular weight: 1,000,000) were subjected to a crosslinking reaction at 80 ° C for 6 hours to obtain a star-shaped hydrophilic polyurethane PU1.

<Preparation Example 2> Star-shaped hydrophilic polyurethane PU2

0.5 mol of PPG6000 triol was mixed with 2.5 mol of HDI, and reacted at 80 ° C for 1 hour to obtain a star-shaped prepolymer, and then 0.85 mol of PEG 1000, 0.85 mol of PEG 2000 and 0.1 mol of hyaluronic acid (weight average molecular weight of 1,000,000) were added. The crosslinking reaction was carried out at 80 ° C for 6 hours to obtain a star-shaped hydrophilic polyurethane PU2.

<Example 1> Wet wound dressing DR1

Referring to Fig. 1, the star-shaped hydrophilic polyurethane PU1 of Preparation Example 1 and 1 mol of HDI were mixed and stirred, and then coated on a release film, and heated at 120 ° C for 1 hour to obtain a sheet-like absorption layer 1 as shown in Fig. 1, that is, The wet wound dressing DR1 of Example 1.

<Example 2> Wet wound dressing DR2

Referring to Figures 1 and 2, 0.1 mol of sodium hydrogencarbonate (foaming agent), 0.4 mol of water, 0.5 mol of polydimethyloxane-polyoxyalkylene copolymer (interface) The active agent), 0.1 mol of ethylenediamine and 0.1 mol of zinc isooctanoate (catalyst, purchased from Taiwan Tin Sangjin Chemical Industry Co., Ltd., model TMG620) were mixed to obtain a foaming component, followed by the star of Preparation Example 2. The hydrophilic polyurethane PU2 is rapidly stirred and mixed with the foaming component to obtain a hydrophilic polyurethane foam after foam molding, and the pores of the hydrophilic polyurethane foam are discontinuous closed pores. The hydrophilic polyurethane foam is cut into a sheet-like absorbent layer 1 of an appropriate size, and fixedly adhered to a viscous backing 21, and a release paper 22 is covered on the sheet-like absorbent layer. On the backing 21, the wet wound dressing DR2 of Example 2 was obtained.

<Comparative Example 1> Wound dressing CDR1

The wound dressing CDR1 of Comparative Example 1 was a general gauze.

<Comparative Example 2> Wound dressing CDR2

The wound dressing CDR 2 of Comparative Example 2 was a soft wound dressing 3662A commercially available from 3M Company, and the material in contact with the wound was a non-woven fabric.

<Comparative Example 3> Wet wound dressing CDR3

Comparative Example wet wound dressing CDR3 3 is commercially available from AMED aqueous gel wound dressing HERADERM ^®, which material is in contact with the wound 2-hydroxyethyl methacrylate (HEMA).

<Wound healing test> A. Experimental animals:

The S. D. rats used in the experiments below were male Sprague-Dawley (S.D.) rats (8 weeks old and weighing 200 g). All experimental animals were housed in an independent air-conditioned animal room with light and dark for 12 hours, room temperature at 22 ° C and relative humidity maintained at 42%. And the water and feed are fully supplied. Animals were given at least 2 weeks to adjust to the environment prior to the experiment. The feeding environment, treatment, and all experimental procedures for experimental animals are in accordance with the National Institutes of Health (NIH) Guide for the Care and Use of Laboratory Animals.

B. Sterilization of biofiber dressings:

The wound dressings DR1, DR2 and CDR1 obtained in the above Examples 1, 2 and Comparative Example 1 were sterilized by gamma ray (dose of 40 kGy), and then subjected to the following experiment.

C. Formation of skin wounds:

The dosal part of the S.D. rat was shaved and then disinfected with tincture of iodine and 70% alcohol. Thereafter, a skin wound having an area size of about 2 cm × 2 cm and a depth of about 2 to 3 mm was cut out on the left side of the back of the S.D. rat using a surgical knife.

D. Application of dressings:

SD rats were randomly divided into 2 experimental groups and 3 control groups (ie, experimental group 1, 2 and control group 1 to 3) (n=3 in each group), in which SD rats of each group were in accordance with the above The method described in item C to form a skin wound. Next, the skin wounds of the SD rats of the experimental groups 1 and 2 were respectively administered with the sterilized wet wound dressings DR1 and DR2 prepared according to the above item B, while the SD rats of the control groups 1, 2 and 3 were administered. Skin wounds were applied separately for the sterilized wound dressing CDR1 prepared according to item B above, the wound dressing CDR2 of Comparative Example 2, and the wet wound of Comparative Example 3, respectively. Dressing CDR3. The experiment was carried out for a total of 7 days, and the wound area of each group of S.D. rats was measured at 1, 3, 5, and 7 days after the application of the dressing, and the results are shown in Table 1 below.

It can be seen from the above Table 1 that the skin wound area of the SD rats of the experimental groups 1 and 2 was significantly reduced on the 1st to 7th day after the application of the dressing, wherein the skin wound of the SD rats of the experimental group 2 was On the 7th day after the application of the dressing, it almost completely healed, while in the control group 1 to 3, the skin wounds in the SD rats were significantly slower in area, indicating that the wet wound dressings DR1 and DR2 of the experimental groups 1 and 2 were wound healing. It has more significant help than the gauze of the control group 1~3 or the commercially available dressing wound dressings CDR1~CDR3.

In summary, the wet wound dressing of the present invention can effectively promote wound healing by the sheet-like absorbent layer, and can absorb wound exudate, and can avoid removal by the closed pore of the hydrophilic polyurethane foam. The damage caused. In addition, the raw material of the present wet wound dressing does not contain a monomer or a cross-linking agent which may be toxic, so that the object of the present invention can be achieved.

However, the above is only the embodiment of the present invention, and when it is not possible to limit the scope of the present invention, all the simple equivalent changes and modifications according to the scope of the patent application and the contents of the patent specification are still This new patent covers the scope.

1‧‧‧Flake absorption layer

21‧‧‧Backing

22‧‧‧ release paper

Claims (10)

A wet wound dressing comprising a sheet-like absorbent layer made of a hydrophilic polyurethane or a foam thereof, wherein the hydrophilic polyurethane reacts a first polyether polyol with a polyisocyanate, and then A star-shaped block polyurethane obtained by reacting a second polyether polyol and hyaluronic acid, the first polyether polyol containing at least three terminal hydroxyl groups. The wet wound dressing of claim 1, further comprising a backing and a release paper, the sheet-like absorbent layer being fixed to the backing, the release paper covering the sheet-shaped absorbent layer and the back Lined up. The wet wound dressing of claim 1, wherein the hyaluronic acid has a weight average molecular weight ranging from 500,000 to 2,500,000. The wet wound dressing according to claim 1, wherein the hyaluronic acid is 100 mol% of the total of the first polyether polyol, the polyisocyanate, the second polyether polyol, and the hyaluronic acid. The content ranges from 0.001 to 20 mol%. The wet wound dressing of claim 1, wherein the polyisocyanate is an aliphatic polyisocyanate. The wet wound dressing of claim 1, wherein the first polyether polyol is poly(propylene glycol) triol. The wet wound dressing of claim 1, wherein the second polyether polyol is polyethylene glycol. The wet wound dressing of claim 7, wherein the polyethylene glycol has a weight average molecular weight ranging from 1,000 to 6,000. The wet wound dressing of claim 1, wherein the hydrophilic polyurethane The pores of the ester foam are discontinuous closed pores, and the hydrophilic polyurethane foam is obtained by foaming the hydrophilic polyurethane and a foaming component. The wet wound dressing of claim 9, wherein the foaming component comprises a blowing agent, water, a surfactant, a polyamine, and a catalyst.