HK1082707B - Moisture barrier resins - Google Patents

Description

Moisture barrier resins

Technical Field

The present invention relates to moisture barrier resins. More particularly, the present invention relates to moisture barrier resins made from film-forming, crosslinkable, partially hydrolyzed polymers. The invention also relates to a method for producing these moisture barrier resins.

The moisture barrier resins of the present invention are useful in coating compositions for a variety of encapsulation processes including microencapsulation and macroencapsulation. The latter two encapsulation processes are generally distinguished by the size of the particles, substances or other core materials being encapsulated.

In light of the above disclosure, the present invention will be described with particular reference to the use of these moisture barrier resins in microencapsulated coating compositions for phosphor particles. However, it is to be understood that the present invention may be used in coating compositions for encapsulating other particles (e.g., drugs, inorganic solvents, inorganic solids, pigments, dyes, epoxy resins, and inorganic salts), for coating electronic components (e.g., printed circuit boards, hybrid integrated circuit boards, high voltage power supplies, wires, and cables), for coating metal substrates (e.g., steel reinforcements for concrete, structural steel, automotive parts, and decorative metals), and for coating glass and film products (e.g., motion picture films, glass substrates, prints, and transparencies).

Background

Encapsulated particles are well known in the art. U.S. Pat. No. 3,674,704(1972) to Bayless et al discloses a process for the co-production of microcapsules in a liquid manufacturing carrier, wherein the capsules contain water or an aqueous solution. This patent discloses a specific method of making a microcapsule wherein the wall material is poly (ethylene-vinyl acetate) which is hydrolyzed to a narrowly specified degree (38-50% hydrolysis).

U.S. Pat. No. 4,107,071(1978) to Bayless discloses microcapsules in which the capsule core material is surrounded by a relatively impermeable dense protective wall, and also discloses a process for making such microcapsules.

General encapsulation methods for providing capsule wall materials for encapsulating a capsule core material to be encapsulated using liquid-liquid phase separation are disclosed in U.S. patent 3,155,590 to Miller et al; U.S. patent 3,415,758 to Powell et al; and Wagner et al, U.S. patent 3,748,277.

Other prior art references disclose encapsulation of electroluminescent phosphors, see U.S. Pat. No. 5,968,698(1999) to Budd. Furthermore, the prior art discloses methods for coating luminescent powders with coatings comprising silica, see U.S. Pat. No. 5,744,233(1998) to Opitz et al.

Phosphors have a variety of applications, such as flat panel displays and ornaments, cathode ray tubes, fluorescent lighting, and the like. Application of heat (thermoluminescence), light (photoluminescence), high energy radiation (e.g., x-rays or electron beams), or an electric field (electroluminescence) can excite the phosphor particles to fluoresce or emit light.

For various reasons, the prior art fails to provide resin coatings having the desired properties of resistance to moisture penetration. Accordingly, there is a need in the industry for resin coating layers with significantly improved properties.

Summary of The Invention

In short, the present invention provides moisture barrier resins that have increased resistance to the adverse effects of moisture and that can function over extended periods of time (i.e., extended release capacity). The invention also provides methods of making these resins.

The above-mentioned advantages of the moisture barrier resins of the present invention are apparent when compared to prior art resins.

The following terms used in this application have the definitions set out below:

"moisture permeation resistance" -the ability to prevent or substantially eliminate moisture absorption and thus avoid the side effects of moisture.

"improved" -in comparison to the resins disclosed in the prior art.

As will be seen from the more detailed description that follows, the moisture barrier resins of the present invention have other properties that are equivalent to or significantly improved over the corresponding properties of the prior art resins.

It is therefore an object of the present invention to provide moisture barrier resins.

It is another object of the present invention to provide moisture barrier resins formed from film-forming, crosslinkable, partially hydrolyzed polymers.

It is another object of the present invention to provide moisture barrier resins having improved resistance to moisture penetration.

It is another object of the present invention to provide moisture barrier resins having extended release capabilities.

It is another object of the present invention to provide a moisture barrier resin for use in coating compositions for encapsulation processes.

It is another object of the present invention to provide moisture barrier resins for use in coating compositions for microencapsulation and macroencapsulation processes.

It is a further object of the present invention to provide a method of making a moisture barrier resin.

It is a further object of the present invention to provide a process for making moisture barrier resins from film-forming crosslinkable partially hydrolyzed polymers.

It is a further object of the present invention to provide a method of making a moisture barrier resin having improved moisture permeation resistance.

It is a further object of the present invention to provide a method of making a moisture barrier resin having extended release capabilities.

It is a further object of the present invention to provide a method of making a moisture barrier resin for a coating composition for use in an encapsulation process.

It is a further object of the present invention to provide a method of making a moisture barrier resin for use in coating compositions for microencapsulation and macroencapsulation processes.

Brief Description of Drawings

The effect of exposure (in hours) on the brightness of the microencapsulated electroluminescent phosphor and on the brightness of the non-microencapsulated electroluminescent phosphor is shown in the graph of figure 1.

Referring to fig. 1, when tested in a humidity chamber for 1,000 hours, the lamps containing phosphors that were microencapsulated using the moisture barrier resin of the present invention showed only 34% degradation, which is 60% less than the degradation exhibited by electroluminescent lamps containing phosphors that were not microencapsulated using the moisture barrier resin of the present invention.

Furthermore, when electroluminescent and incandescent lamps of microencapsulated phosphors using the moisture barrier resin of the present invention were tested as racetrack lamps, the electroluminescent lamps did not produce halos or glare and were still visible at distances nearly three times as far as the incandescent lamps. The same results were observed in cold conditions.

Fig. 2 is a graphical representation of the relationship between capsule mass and percent hydrolysis of partially hydrolyzed poly (ethylene-vinyl acetate). For reasons not fully understood, the mass change as a function of the percentage hydrolysis is quite significant. At a degree of hydrolysis of less than about 38%, the separated phase prepared according to known liquid-liquid phase separation techniques is not sufficiently viscous to form a useful capsule wall, which is viscous and often difficult to control in an attempt to separate the capsules. Capsules made with materials having a degree of hydrolysis of less than 38% have a tendency to aggregate during the microencapsulation process, since the absence of vinyl alcohol groups prevents sufficient crosslinking through hydroxyl groups.

At a degree of hydrolysis greater than 55%, the separated phase is too viscous and a viscous, abrupt phase exists as a semisolid. The change from "good" to "not good" is abrupt and appears to be completed within a few percent.

When the hydrolysis degree is between 38% and 43%, the quality of the capsule can be improved, and when the hydrolysis degree is close to 43%.

At hydrolysis degrees between 43% and 53%, the quality of the capsules is excellent for the present invention, and the capsules are particularly suitable for containing phosphors, polar liquids and other substances for extended periods of time.

At a hydrolysis degree of between 53% and 54% or 55%, the capsule quality rapidly decreases, and at a hydrolysis degree of 56%, quality capsules can no longer be successfully produced.

As shown in fig. 2, the quality of the capsules is best for the present invention at a degree of hydrolysis between 44% and 46%. Although an accurate capsule mass value within this hydrolysis range cannot be specifically determined, as shown in fig. 2, the capsule mass is significantly improved compared to the capsule mass below this hydrolysis range.

Detailed Description

The present invention relates to moisture barrier resins comprising a film-forming, crosslinkable, partially hydrolyzed polymer and a crosslinking agent.

The particles, substances or other core materials encapsulated with the moisture barrier resin according to the present invention have improved resistance to moisture penetration compared to particles, substances or other core materials encapsulated with other film forming polymers according to the prior art.

As mentioned above, the present invention will be described in detail with particular reference to phosphor particles, but the moisture barrier resins of the present invention can also be effectively used to encapsulate and/or coat other particles, substances and core materials.

The phosphor microencapsulated using the moisture barrier resin of the present invention comprises a core material, typically in the form of particles, formed of a phosphor, and a film-like shell surrounding and enclosing the core material. The envelope comprises a partially hydrolysed cross-linked polymer (according to the invention) which is sufficiently impermeable to moisture (particularly water) to protect the phosphor from damage by exposure to moisture, but the cross-linked polymer is sufficient to allow the transfer of luminescent energy to excite the phosphor to a luminescent state. These microcapsules are therefore particularly suitable for use in light-emitting applications.

Generally, the phosphor particles are mixed with the moisture barrier resin of the present invention and a liquid carrier which is a solvent for the resin but not for the phosphor particles. The mixture is stirred to dissolve the resin in the liquid carrier and to disperse the phosphor particles throughout the solution. A coacervation process is performed to induce phase separation of the solution, thereby separating the resin from the liquid carrier, and a film-like shell of the resin is applied to the phosphor. The polymer shell around the phosphor is crosslinked to harden the resin and render the resin shell sufficiently impermeable to protect the phosphor from damage from exposure to moisture conditions. The resin-encapsulated phosphor particles are recovered from the solution, washed and dried.

After the phosphor is recovered from the process, the resin shell is preferably contacted with a halogenated hydrocarbon to coat the resin shell on the phosphor, thereby improving the water resistance of the resin shell. Preferred halogenated hydrocarbons are 1, 1, 2-trichloro-1, 2, 2-trifluoroethane and dibromotetrafluoroethane.

Film-forming, crosslinkable, partially hydrolyzed polymers

The polymer should be substantially insulating, preferably having a dielectric constant of less than about 2.2, preferably in the range of about 1.8 to 2.2. Various polymers may be employed to form the protective film-like shell of the microcapsules. For some applications, the polymer should be thermally decomposable.

The polymeric capsule wall material can be any film-forming polymeric material that wets the phosphor core material. The capsule wall material is preferably a partially hydrolyzed poly (ethylene-vinyl acetate) containing 60 to 88 mole percent ethylene, some of the vinyl acetate groups of which are hydrolyzed to form vinyl alcohol groups that provide reactive sites for subsequent crosslinking. The degree of hydrolysis of the poly (ethylene-vinyl acetate) can range broadly from about 38% to about 55%, preferably from about 44% to about 46%.

Thus, a partially hydrolyzed copolymer of ethylene and vinyl acetate includes an ethylene group, a vinyl acetate group, and a vinyl alcohol group, and may be represented by the following general formula:

wherein x, y and z represent the mole fractions of ethylene, vinyl alcohol and vinyl acetate, respectively. The molar ratio of vinyl alcohol groups to the sum of vinyl alcohol groups and vinyl acetate groups is about 0.15 to 0.7 in terms of the degree of hydrolysis. The amount of vinyl groups present is also important and can range from about 60 to 88 mol%. In other words, the molar ratio of vinyl groups to the sum of vinyl groups, vinyl alcohol groups, and vinyl acetate groups is from about 0.6 to about 0.88.

The partially hydrolyzed poly (ethylene-vinyl acetate) suitable for practicing the present invention has a molecular weight of about 50,000 and a melt index (2160 g force at 190 ℃,10 minutes) of about 5 to 70, preferably about 35 to 45. The molecular weight of the polymer is not very critical, but in case the molecular weight is too high, the polymer will be relatively insoluble in the liquid carrier optionally constituting the main part of the microcapsule system. If the molecular weight of the polymer is too low, it may be difficult to cause phase separation during microencapsulation. Other suitable polymeric wall materials are poly (ethylene-formal) polymers, poly (vinyl-butyral) polymers, alkylated celluloses (e.g., ethyl cellulose), acylated celluloses (e.g., cellulose acetate butyrate), and the like.

Preferred polymers of the present invention are poly (ethylene-vinyl acetate) having a melt index of about 35 to about 37 and having from about 44% to about 46% of vinyl acetate groups hydrolyzed to vinyl alcohol groups. This polymer has an ethylene content of about 70%, a vinyl alcohol content of about 10% to 14% (most preferably about 12.5% to 13%), and a vinyl acetate content of about 16% to about 20% (most preferably about 17% to about 18%).

In the (ethylene-vinyl acetate) of the present invention, the melt index will be too high or too low if the ethylene content is too high or too low, respectively. Furthermore, if the content of vinyl alcohol is too high, these polymers become too hygroscopic. Further, if the vinyl acetate content is too high, the properties of the polymer are reduced.

Use of solvents

Although not essential to the invention, the moisture barrier resin may optionally be a solvent-based mixture. Generally, the desired thickness of the coating layer will determine whether a solvent is beneficial, with thinner coatings made from a mixture of resin and crosslinker, based on the solvent. Preferably, the solvent employed is an organic non-polar solvent.

Typical exemplary water-immiscible liquids that can be used as the liquid carrier for the moisture-lined resin are solvents for the polymerized wall material, including liquid aromatic hydrocarbons such as toluene, xylene, benzene, chlorobenzene, and the like; and liquid halogenated hydrocarbons such as trichloroethylene, tetrachloroethylene, carbon tetrachloride, methyl chloride, and the like. Other suitable solvents are for example cyclohexanol, methyl isobutyl ketone, 1-methyl-2-pyrrolidone, butanol, etc.

Microencapsulated particles of a substance

A detailed description of phosphors that can be microencapsulated (i.e., coated) using the moisture barrier resins of the present invention can be found in the applicants' co-pending U.S. patent application serial No. 09/989,359 entitled "microencapsulated particles and methods for making same" filed on year 2001, 11/20, the disclosure of which is incorporated herein. Pending application serial No. 09/989,359 also discloses a method of microencapsulating phosphor particles, which includes phase separation of the solution, the disclosure of which is also incorporated herein.

Crosslinking of film-forming crosslinkable partially hydrolyzed polymers

Suitable cross-linking agents for hardening the microcapsules according to the invention include diisocyanates or polyisocyanates, such as toluene diisocyanate, with or without the presence of a catalyst. Particularly preferred is a toluene diisocyanate-trimethylolpropane adduct, which is typically dissolved in an aliquot of the liquid carrier. Other suitable crosslinking agents are diacid-based halides such as malonyl chloride, oxalyl chloride, sulfonyl chloride, thionyl chloride, and the like; and bifunctional hydrides. Examples of other classes of suitable crosslinking agents are alkali metal alkoxides such as sodium, potassium, lithium and cesium methoxide, ethoxide, propoxide, and the like.

To achieve the desired chemical hardening of the formed shell and thus provide a protective capsule wall, the cross-linking or hardening agent may be dissolved in an aliquot of the liquid carrier or other compatible solvent and then added to the suspension of the capsule core covered with shell. The crosslinking is then carried out at a temperature of from about 0 ℃ to about 50 ℃ for a crosslinking time of from about 5 minutes to about 20 hours, depending on the crosslinker employed. When a diacid halide is employed, the crosslinking time may be from about 5 to about 15 minutes, while when a diisocyanate is employed, the crosslinking time may be from about 5 to about 15 hours, depending on the reaction conditions.

The shell of the microcapsules may be hardened or cross-linked by exposing the shell to high energy ionizing radiation such as accelerated electrons, X-rays, gamma rays, alpha rays, neutrons, and the like.

The permeability of the protective wall of the microcapsules depends to a large extent on the degree of crosslinking that has been achieved and that the protective wall can be made to have as required by the end use.

For the film-forming, crosslinkable, partially hydrolyzed polymers of the present invention, the ratio of polymer to crosslinker is from about 1:0.2 to about 1:1, preferably from about 1:0.3 to 1: 1. It was found that at this ratio close to 1:1, the properties of the moisture barrier continued to increase, but at a lower rate, while the flexibility of the polymer tended to decrease.

Capsules of various sizes can be prepared using the moisture barrier resins of the present invention, and these sizes can range from an average diameter of about 1 micron or less to about several thousand microns or more. The typical size of the resulting capsules is about 1 micron to 15,000 microns in average diameter, with a preferred average diameter range of about 5 microns to about 2,500 microns. Similarly, capsules having varying amounts of core material may be manufactured, wherein the core material comprises up to about 99% or more of the total weight of each capsule. Preferably, the core material comprises from about 50% to about 97% of the total weight of each capsule.

To illustrate the process of the present invention, a solution of a liquid carrier, such as toluene, and a film-forming polymeric material comprising a partially hydrolyzed ethylene vinyl acetate copolymer (HEVA) having from about 38% to about 55%, preferably from about 44% to about 46%, of the vinyl acetate groups hydrolyzed to form vinyl alcohol groups is prepared at an elevated dissolution temperature suitably above 70 ℃, preferably from about 75 ℃ to about 100 ℃. The resulting solvent is then ready to receive the phosphor core material. Preferably, the solvent is allowed to cool to a dispersion temperature of about 30 ℃ to about 65 ℃ (the cooling step may be performed at room temperature or may be accelerated with cold air, ice, etc.). The phosphor particles having an average diameter in the range of about 5 to about 50 microns are then added to the HEVA-toluene solvent under vigorous stirring to disperse the phosphor throughout the phosphor particles in the HEVA-toluene solution.

Then, a phase separation inducing agent such as cottonseed oil is added to cause liquid-liquid phase separation of the HEVA copolymer from the toluene solvent, and the resulting mixture is then cooled to a phase separation temperature in the range of from about 15 ℃ to about 50 ℃, preferably from about 20 ℃ to about 30 ℃, while continuing to stir to maintain the particles dispersed (the cooling step may be carried out at room temperature, or cooling may be accelerated using cold air, ice, or the like). However, the phase separation inducer may also be added earlier than the phosphor core material, for example. When phase separation begins in the system, the wall-forming HEVA copolymer material separates out as another discontinuous phase (i.e., a third phase) that wets the phosphor core and forms an outer shell or capsule wall. This third phase is a concentrated solution or gel of polymeric material, more viscous than the continuous phase, and has a viscosity high enough to maintain a substantially continuous shell around the dispersed phosphor core despite the shear forces associated with the force required to maintain overall dispersibility.

Next, a cross-linking agent, such as Toluene Diisocyanate (TDI) adducted with trimethylolpropane in toluene, is added to the cooled mixture to cross-link the HEVA shell deposited around the phosphor core as a result of the addition of the phase separation inducer cottonseed oil. After the addition of the TDI adduct, the resulting mixture was further cooled to a temperature ranging from about 0 ℃ to about 20 ℃ with continued stirring and then warmed to room temperature. Stirring was continued until crosslinking was complete. Thereafter, the produced microcapsules are recovered, washed and dried.

Thereafter, the microcapsules are contacted with the halogenated hydrocarbon, if desired, by suspending the microcapsules in 1, 1, 2-trichloro-1, 2, 2-trifluoroethane. This washing shrinks the shell or wall of the microcapsules and prevents the microcapsules from aggregating. Finally, the microcapsules are dried, preferably by treating them with silica gel in the form of micron-sized particles to prevent aggregation of the microcapsules.

The present invention is further illustrated by the following examples, which are intended to be exemplary of certain embodiments which are intended to teach one of ordinary skill in the art how to practice the invention and which are representative of the best mode contemplated for carrying out the invention.

Example 1

60g of partially hydrolyzed ethylene-vinyl acetate copolymer (HEVA, sold under the trademark Japan8 by Mitsui corporation) having 44-52% of the vinyl acetate groups hydrolyzed to vinyl alcohol groups and having a melt index of 35-37 was added to 2400ml of toluene in a 41 beaker equipped with a 4-inch turbine paddle on a variable speed agitator motor. The solution was heated to 85 ℃ and stirred for 15 minutes to dissolve the HEVA copolymer in toluene. The heat source was then removed and the temperature was reduced to 58 ℃. At this point, 900g of green phosphor particles having an average particle diameter in the range of 10 to 40 microns were added to a solution of HEVA in toluene with vigorous stirring using a stirrer at a stirring speed of up to 480rpm to substantially uniformly disperse the phosphor particles throughout the toluene solution. At approximately the same time cottonseed oil (in an amount sufficient to form an 11% by weight solution of cottonseed oil) was added to the toluene solution to induce liquid-liquid phase separation. At 42 ℃, the stirrer was decelerated to 430rpm and the beaker was placed in an ice bath. The resulting mixture is then cooled to about 22 ℃ with sufficient agitation to keep the phosphor particles in suspension dispersed.

To the cooled mixture was then added a solution of 71.4g of toluene diisocyanate adducted with trimethylolpropane (sold by Mobay Chemicals under the trademark Desmodur CB-75N) dissolved in toluene to effect crosslinking and thus harden the HEVA shell deposited around the core material as a result of the addition of cottonseed oil. After the addition of the diisocyanate, the resulting mixture was further cooled to about 10 ℃ and then allowed to warm to ambient temperature while continuing to stir. Stirring was continued until crosslinking was complete.

The resulting microcapsules were recovered by filtration, washed with toluene, and then suspended in 1250ml of 1, 1, 2-trichloro-1, 2, 2-trifluoroethane for 5 to 10 minutes to shrink the wall to improve the water resistance of the wall and prevent aggregation of the microcapsules during filtration and drying. The suspension is repeated 3 more times, after which the microcapsules are filtered off and washed again with a small amount of 1, 1, 2-trichloro-1, 2, 2-trifluoroethane. The capsules are then mixed with ground silica gel (sold under the trade mark Syloid 74, w.r.grace co.) to help prevent aggregation of the microcapsules. The Syloid/microcapsule mixture was passed through a 500 micron sieve and then through a 106 micron sieve, and then dispersed on trays for drying. The yield was about 80%.

Example 2

The process of example 1 was successfully repeated using 900g of blue phosphor particles having an average diameter in the range of about 10 microns to about 40 microns.

Example 3

The process of example 1 was successfully repeated using 600g of yellow phosphor particles having an average diameter in the range of about 10 microns to about 40 microns.

Example 4

The process of example 1 was successfully repeated using a hydrolyzed ethylene vinyl acetate polymer having 44-46% of the vinyl acetate groups hydrolyzed to vinyl alcohol groups.

Example 5

The partially hydrolyzed poly (ethylene-vinyl acetate) of example 4, present in a mixture formed with toluene and a crosslinking agent, was applied to the surface (without the dispersed internal phase) and allowed to cure. The obtained protective cross-linked film can be applied to substrates of various sizes meeting the basic requirements of packaging technology.

Crosslinked, partially hydrolyzed poly (ethylene-vinyl acetate) can be applied with various coating materials such as paints.

The present invention has been described with particular reference to certain embodiments thereof, however, various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the following claims.

Claims (44)

1. A moisture barrier resin comprising a mixture of (a) a film-forming, crosslinkable, partially hydrolyzed polymer and (b) a crosslinking agent, wherein the polymer has a degree of hydrolysis of from 44% to 46%.

2. A moisture barrier resin as defined by claim 1 wherein the film-forming, cross-linkable, partially hydrolyzed polymer is poly (ethylene-vinyl acetate).

3. A moisture barrier resin as defined by claim 1 wherein the cross-linking agent is a diisocyanate or polyisocyanate.

4. A moisture barrier resin as defined by claim 1 wherein the cross-linking agent is toluene diisocyanate.

5. A moisture barrier resin as defined by claim 1 wherein the cross-linking agent is a toluene diisocyanate-trimethylolpropane adduct.

6. A moisture barrier resin as defined by claim 1 wherein the polymer comprises poly (ethylene-vinyl acetate) having a melt index of 35 to 37 and 44 to 46 percent of the vinyl acetate groups in the poly (ethylene-vinyl acetate) are hydrolyzed to vinyl alcohol groups.

7. The moisture barrier resin of claim 6 wherein the polymer has an ethylene content of from 60 mol% to 88 mol%.

8. A process for the manufacture of a moisture barrier resin, wherein the process comprises reacting a film-forming, crosslinkable, partially hydrolyzed polymer and a crosslinking agent, wherein the polymer has a degree of hydrolysis of from 44% to 46%.

9. The method of claim 8, wherein the film-forming, crosslinkable, partially hydrolyzed polymer is poly (ethylene-vinyl acetate).

10. The method of claim 8, wherein the crosslinker is a diisocyanate or polyisocyanate.

11. The method of claim 8, wherein the crosslinker is toluene diisocyanate.

The method of claim 8, wherein the crosslinker is a toluene diisocyanate-trimethylolpropane adduct.

13. An encapsulated material having improved moisture penetration resistance wherein the material is encapsulated with a composition comprising a moisture barrier resin comprising a mixture of (a) a film-forming, cross-linkable, partially hydrolyzed polymer having a degree of hydrolysis of from 44% to 46%, and (b) a cross-linking agent.

14. An encapsulated substance as defined by claim 13 wherein the film-forming, cross-linkable, partially hydrolyzed polymer is poly (ethylene-vinyl acetate).

15. An encapsulated substance as defined by claim 13 wherein the cross-linking agent is a diisocyanate or polyisocyanate.

16. An encapsulated substance as defined by claim 13 wherein the cross-linking agent is toluene diisocyanate.

17. An encapsulated substance as defined by claim 13 wherein the cross-linking agent is a toluene diisocyanate-trimethylolpropane adduct.

18. An encapsulated substance as defined by claim 13, wherein the substance is a phosphor.

19. A substrate coated with a moisture barrier resin, wherein the moisture barrier resin comprises a mixture of (a) a film-forming, cross-linkable, partially hydrolyzed polymer and (b) a cross-linking agent, and the polymer has a degree of hydrolysis of from 44% to 46%.

20. The coated substrate of claim 19, wherein the substrate comprises a drug.

21. The coated substrate of claim 19, wherein the substrate comprises an inorganic solvent.

22. The coated substrate of claim 19, wherein the substrate comprises an inorganic solid.

23. The coated substrate of claim 19, wherein the substrate comprises a pigment.

24. The coated substrate of claim 19, wherein the substrate comprises a dye.

25. The coated substrate of claim 19, wherein the substrate comprises an epoxy.

26. The coated substrate of claim 19, wherein the substrate comprises an inorganic salt.

27. The coated substrate of claim 19, wherein the substrate comprises particles of a drug, an inorganic solvent, an inorganic solid, a pigment, a dye, an epoxy resin, or an inorganic salt.

28. The coated substrate of claim 19, wherein the substrate comprises an electronic component.

29. The coated substrate of claim 19, wherein the substrate comprises a printed circuit board.

30. The coated substrate of claim 19, wherein the substrate comprises a hybrid integrated circuit board.

31. The coated substrate of claim 19, wherein the substrate comprises a high voltage power supply.

32. The coated substrate of claim 19, wherein the substrate comprises a wire.

33. The coated substrate of claim 19, wherein the substrate comprises a cable.

34. The coated substrate of claim 19, wherein the substrate comprises a metal substrate.

35. The coated substrate of claim 19, wherein the substrate comprises concrete rebar.

36. The coated substrate of claim 19, wherein the substrate comprises structural steel.

37. The coated substrate of claim 19, wherein the substrate comprises an automotive part.

38. The coated substrate of claim 19, wherein the substrate comprises a decorative metal.

39. The coated substrate of claim 19, wherein the substrate comprises glass.

40. The coated substrate of claim 19, wherein the substrate comprises a film product.

41. The coated substrate of claim 19, wherein the substrate comprises a motion picture film.

42. The coated substrate of claim 19, wherein the substrate comprises a film print.

43. The coated substrate of claim 19, wherein the substrate comprises a slide.

44. The coated substrate of claim 19, further comprising a second coating formed on the moisture resistant resin.

45. A crosslinked film formed from a moisture barrier resin, wherein the moisture barrier resin comprises a mixture of (a) a film-forming, crosslinkable, partially hydrolyzed polymer and (b) a crosslinking agent, and the polymer has a degree of hydrolysis of from 44% to 46%.