Method for protecting and repairing rotten wood of ancient ship

Abstract

The application discloses a kind of ancient ship rotten wood protection repair method, for the pine, fir, camphor wood on ancient ship, after the oxidation-reduction reaction of iron and the oxidation of reduced state sulfur, cause the degradation and rotten of wood, with micro-nano lime and ethyl cellulose deacidification reinforcement;For the crack and incomplete parts of ancient ship, make into imitation wood grain paste with tung oil etc. and fill the vacancy;For broken wood block, make into rotten wood adhesive with tung oil etc. and bond;For the ancient ship protection after repair, use fluorine rubber as sealing agent, provide a good environment for cultural relics, achieve waterproof, mildewproof, insect prevention and other effects.The method of the application replaces the traditional polyethylene glycol penetration spray method, rosin paraffin hot infiltration method, polyvinyl alcohol, polyethylene glycol penetration reinforcement, spraying raw tung oil, raw lacquer, B72 and epoxy resin and other protection methods, and uses fluorine rubber as ancient ship sealing agent, achieves the purpose of traditional and modern material combination of cultural relic protection "repairing old as old, minimal intervention".

Description

Technical Field

[0001] This invention belongs to the field of wooden cultural relic protection and restoration technology, and specifically relates to the protection and restoration of unearthed ancient wooden boats. Background Technology

[0002] Before ancient wooden boat artifacts are excavated, their underwater or underground burial environment is relatively stable, placing them in a state of relative and temporary dynamic equilibrium. However, with archaeological excavation, this inherent equilibrium is disrupted, particularly by sudden changes in temperature, humidity, and light, causing a rapid abrupt change in the artifacts. Without timely rescue and protection, or if improperly protected, the ancient wooden boats may shrink, crack, warp, or deform. Wooden artifacts recovered from the ocean often contain reduced sulfur, which, under oxidizing conditions, causes acidification and degradation of the wood fibers. Furthermore, the redox reactions of iron in the wood can accelerate degradation, leading to decay. This is a common challenge faced by cultural relic conservationists.

[0003] Internationally, methods for protecting salvaged shipwreck timber include polyethylene glycol (PEG) penetrating spraying, rosin and paraffin hot-dip filtration, and sucrose penetrating. Domestic methods for protecting salvaged shipwreck timber include: spraying 5%–7% polyvinyl acetate acetone solution to treat severely decayed pieces; applying or spraying raw tung oil; using rosin and paraffin hot-dip filtration; employing polyvinyl alcohol and PEG penetrating reinforcement techniques; spraying sodium fluoride and pentachlorophenol alcohol solutions for insect and rot prevention; previously, restoration of the wood grain was generally not performed on damaged or rotten parts of the ship; bonding fragments using wood glue, epoxy resin, B72 resin, or unsaturated polyester resin; and reinforcing rotten timber with lacquer.

[0004] The above methods and techniques have a certain protective effect on cultural relics, but they also have some major defects: (1) Spraying polyvinyl acetate acetone solution and raw tung oil, although high-pressure gas sprayed from an air compressor was used to spray the chemical protective materials, and a 5% polyvinyl acetate acetone solution was selected to facilitate the penetration of the chemical protective materials into the ship material, the chemical protective materials did not completely penetrate into the ship material when the samples were taken after completion. (2) Raw tung oil dries slowly. If there is rainy and humid weather, the drying of the oil film is further delayed, resulting in mold on the surface of the ship after spraying raw tung oil. (3) Polyethylene glycol is used for protection during the dehydration stage of the archaeological wood, but the treated ancient ship is dark black and loses the color of the wood, resulting in a poor appearance. (4) Due to the corrosion of the iron nails on the ancient ship (there are 6,300 iron nails on the Song Dynasty ship in Quanzhou), the oxidation-reduction of iron promotes the degradation of the ship timber. The oxidation of reduced sulfur in the ship timber produces acid, which causes the wood to degrade and become acidic. This is the main reason for the formation of decay. Therefore, if the decayed wood of the ancient ship is not deacidified, it will be very detrimental to the stability of the ship timber. (5) Lacquer is the main material for making lacquerware, but as a lacquer for reinforcing wood, firstly, it cures slowly, and secondly, the color of the wood darkens after the reinforcement is completed, which does not meet the principle of restoring the old and preserving the old. (6) In the past, when repairing ancient ships, the wood grain of the missing pieces was not restored. This could not meet the requirements of the restoration of cultural relics to be as old as possible. (7) When repairing ancient ships, wood glue, epoxy resin, B72 resin, or unsaturated polyester resin are used to bond the fragments. Except for wood glue, the resin stress after curing is large. If the bonding is not done carefully, the joint is easy to break. Also, like wood glue, the resin will flow when bonding. (8) After the restoration of the ancient ship, no protective sealing treatment was found to mitigate the impact of fluctuations in environmental temperature and humidity on the stability of the ship. (9) No deacidification and reinforcement protection treatment methods were found for the acidified, degraded, and decayed archaeological wood. (10) At present, the difficulty and focus of the protection of ancient wooden shipwrecks after they are brought to the surface is the dehydration and shaping protection after they are brought to the surface. There are relatively mature technologies such as polyethylene glycol method and freeze-drying method, but there is still a lack of corresponding systematic protection and restoration treatment materials and processes for various diseases of wooden shipwrecks in the dry state. Summary of the Invention

[0005] The purpose of this invention is to overcome the above-mentioned defects and provide a method for the protection and restoration of decayed wood from ancient ships that combines traditional and modern materials.

[0006] The method for protecting and restoring decayed wood from ancient ships provided by this invention includes the following steps:

[0007] Step 1: First, use drills of different diameters to forcefully rotate the infusion hole to a depth of 2-4 cm at the reinforcement part of the wooden boat. Then, insert an L-shaped stainless steel needle into the infusion hole to inject the decayed wood deacidification and reinforcement agent. The decayed wood deacidification and reinforcement agent is made by mixing micro-nano lime and an ethanol solution of ethyl cellulose with a mass concentration of 1%-2% in a volume ratio of 1:1-3.

[0008] Step 2: Apply the imitation wood grain paste to the patched area of ​​the ancient ship using a caulking tool and smooth it out. Then, use the imitation wood grain tool to pull and scrape back and forth to create the wood grain. The imitation wood grain paste is made by mixing tung oil, lime, talcum powder and wood chips in a mass ratio of 1:2-3:0.5-2:1-3.

[0009] Step 3: Apply wood rot adhesive to both sides of the wood chips and fix them with rope or tape. The initial setting time is 24 hours and the final setting time is 72 hours. The wood rot adhesive is a mixture of tung oil, lime, wood chips and hemp fibers in a mass ratio of 1:2 to 3:1 to 3:1 to 2.

[0010] Step 4: After completely dissolving the fluororubber in the organic solvent, apply it to the surface of the ancient ship with a paintbrush.

[0011] In step 1 above, the preferred deacidifying and reinforcing agent for decayed wood is a mixture of micro-nano lime and an ethanol solution of ethyl cellulose with a mass concentration of 2% in a volume ratio of 1:2.

[0012] In step 2 above, the imitation wood grain paste is preferably made by mixing tung oil, lime, talc powder and sawdust in a mass ratio of 1:3:0.5:1.

[0013] In step 3 above, the preferred method is to use tung oil, lime, sawdust, and hemp fibers mixed in a mass ratio of 1:2:1:1.

[0014] In step 4 above, the mass concentration of fluororubber in the organic solvent is preferably 3% to 6%, and the fluororubber is preferably fluororubber F2311, which is a copolymer of vinylidene fluoride and trifluorochloroethylene. The organic solvent is any one of acetone, propanol, ethyl acetate, and butyl acetate.

[0015] The beneficial effects of this invention are as follows:

[0016] 1. This invention targets the pine, fir, and camphor wood found on ancient ships, which suffers from degradation due to the redox reaction of iron and the oxidation of reduced sulfur. Based on the characteristics of these defects, a wood deacidifying and reinforcing agent is used for deacidification and penetration reinforcement treatment. Its good permeability can effectively increase the pH value of the wood, while improving the material stability of the deacidified and reinforced wood, thus slowing down the acidification trend and increasing the physical strength of the wood. For example, the average pH value of the decayed wood around the nail holes after deacidification and reinforcement with the wood deacidifying and reinforcing agent was 4.85-4.95 before treatment and 6.19-8.12 after treatment; the average hardness was 33.83-3.9 before treatment and 5.1-51.67 after treatment; and the color of the wood remained basically unchanged after reinforcement, achieving the principle of preserving the original appearance of cultural relics.

[0017] 2. The wood grain imitation paste used in this invention has a clear and realistic wood grain effect, simple process, convenient and quick process, improved efficiency, and is easy to promote. Moreover, the wood grain imitation effect meets the requirements of "restoring the old as before" in cultural relic protection.

[0018] 3. The decayed wood adhesive of this invention is used for bonding fragments of ancient ships. During the bonding process, the adhesive will not flow and can be fixed with rope or tape. It initially sets in 24 hours and finally sets in 72-125 hours. The physical properties such as stress of the cured decayed wood adhesive meet the requirements for wood bonding.

[0019] 4. This invention uses fluororubber as a sealing agent for ancient ships, creating a relatively stable microenvironment for their storage. Utilizing its superior antioxidant, waterproof, anti-pollution, insect-proof, and fire-resistant properties, the sealing film provides long-lasting protection for the ancient ship, enhancing its aging resistance. The fluororubber sealant, once molded, possesses a certain degree of elasticity, thus preventing wooden artifacts from becoming brittle, hard, cracked, or peeling. As a sealing agent, fluororubber does not produce a glossy finish on the artifact's surface, preserving its original appearance; it has high self-cleaning properties, does not attract dust, and is highly reversible, requiring only acetone cleaning for removal. The process is simple, convenient, reliable, low-cost, and highly effective.

[0020] 4. This invention combines traditional materials such as tung oil with modern materials such as ethyl cellulose and fluororubber to form a new method for the protection and restoration of decayed wood from ancient ships. The method is simple, easy to operate, low in cost, and effective, meeting the requirements for the display, collection, restoration, and preservation of cultural relics, and has certain promotional value. Attached Figure Description

[0021] Figure 1 This is a diagram of the reinforcement of rotten wood from an ancient ship from the Southern Song Dynasty using a wood deacidification and reinforcement agent, as shown in Example 1.

[0022] Figure 2 These are before (left) and after (right) renderings of the wood grain imitation paste applied to the damaged parts of the ancient ship from the Southern Song Dynasty in Example 1.

[0023] Figure 3 These are before (left) and after (right) effect images of the rotten wood from the broken ancient ship of the Southern Song Dynasty in Example 1, showing the bonding effect of the wood with a rotten wood adhesive.

[0024] Figure 4 This is an illustration of the waterproof contact angle effect of fluororubber on the rotten wood of the ancient ship from the Southern Song Dynasty before (left) and after (right) sealing, as shown in Example 1. Detailed Implementation

[0025] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments, but the scope of protection of the present invention is not limited to these embodiments.

[0026] The micro-nano lime used in the examples was produced by (Bilin) ​​Zhejiang Desaibao Building Materials Technology Co., Ltd., and the tung oil was provided by Shanghai Huangshi Gongjiang Tung Oil Factory.

[0027] Example 1

[0028] Step 1: First, using drills of different diameters, forcefully rotate downwards to create infusion holes 3-4 cm deep at the rotten wood reinforcement area of ​​the ancient Southern Song Dynasty ship. Then, insert an L-shaped stainless steel needle into the infusion hole to inject a deacidifying and reinforcing agent for the rotten wood. This deacidifying and reinforcing agent is composed of 33 mL of micro-nano lime and 67 mL of a 2% (w / w) ethyl cellulose ethanol solution. For surface powdering and wood loosening caused by fiber degradation, spraying methods often fail to achieve a penetration depth of even 1 cm, based on on-site sampling. However, this step increases the reinforcement depth by approximately 5 times compared to traditional brushing, spraying, or dripping processes. Before the test, the average pH was 4.95 and the average hardness was 33.83; after four days, the pH was 6.19 and the hardness was 51.67. Figure 1 Image a shows the wood before reinforcement (left), and image b shows the wood after reinforcement (right). Depending on the degree of corrosion, the injection depth is generally 3-4 cm. Initial setting on the surface takes about 30 seconds. At 25℃, the final setting time for all the reinforcement is 12 hours, and at 0℃, it is 24 hours. Figure 1 c. It can be seen that before reinforcement, the rotten wood would shed powder severely when touched by hand. After reinforcement, once the reinforcing agent on the surface of the rotten wood has initially set, it no longer sheds powder when touched by hand (see...). Figure 1 d), Figure 1 e is the injection of the reinforcing agent using a syringe; at this point, the rotten wood is yellow. Figure 1 f is a photo of the wood block after injection reinforcement, showing the depth of the injection reinforcement. The black part of the cross-section represents the depth reached by the 3.5cm reinforcement agent, while the light yellow part represents the original wood color area that was not reinforced.

[0029] Step 2: Apply the imitation wood grain paste to the repaired area of ​​the ancient ship using a caulking tool and smooth it out. Then, use the same tool to pull and scrape back and forth to create the wood grain effect, achieving the textures, unevenness, and variations of decayed wood. This achieves the goal of "restoring the old as it was," "looking consistent from a distance," and "distinguishing features upon close inspection" in cultural relic preservation and restoration. Figure 2 The wood grain imitation paste is composed of tung oil, lime, talc powder, and sawdust mixed in a mass ratio of 1:3:0.5:1. This method of imitating wood grain takes only 5 minutes, while the original process of carving wood grain on resin over the same area took 2 hours, increasing work efficiency by 24 times.

[0030] Step 3: Apply wood adhesive to both sides of the wood chips, fix them with tape, and allow to set for 24 hours for initial setting and 72 hours for final setting. The wood adhesive is a mixture of tung oil, lime, sawdust, and hemp fibers in a mass ratio of 1:2:1:1. Results show that the physical properties, such as stress, of the cured wood adhesive meet the requirements for wood bonding. Figure 3 As can be seen, the joints of the five broken and rotten pieces of wood are large due to shrinkage and deformation. If traditional adhesives are used, the resin will flow, making bonding difficult and unsuitable for the stress of ship timber. However, the rotten wood adhesive used in this step uses hemp fibers and wood chips to adjust the consistency of the adhesive, avoiding the above defects and making the operation convenient.

[0031] Step 4: After completely dissolving 5g of fluororubber 2311 in 95g of acetone, apply the solution to the surface of the ancient ship using a paintbrush. Figure 4 It is evident that after fluororubber 2311 cures, it forms a film that creates a relatively stable microenvironment on the surface of the ancient ship. This film not only protects the wood from moisture and water but also prevents wooden artifacts from becoming brittle, hard, cracked, peeling, or developing microorganisms. It does not produce any shine or highlights on the surface of the artifact and has excellent reversibility, achieving the effect of "restoring the old as it was" without altering the original appearance of the artifact.

[0032] Example 2

[0033] Step 1: First, use drills of different diameters to forcefully rotate downwards at the rotten wood reinforcement part of the ancient ship from the Southern Song Dynasty to create an infusion hole to a depth of 3-4 cm. Then, insert an L-shaped stainless steel needle into the infusion hole to inject the rotten wood deacidification and reinforcement agent. The rotten wood deacidification and reinforcement agent is composed of 50 mL of micro-nano lime and 50 mL of ethanol solution with a mass concentration of 2% ethyl cellulose.

[0034] Step 2: Apply the imitation wood grain paste to the repaired area of ​​the ancient ship using a caulking tool and smooth it out. Then, use the imitation wood grain tool to pull and scrape back and forth to create the wood grain effect, achieving the desired texture, depth, and height of decayed wood. This achieves the goal of "restoring the old as it was," "looking the same from a distance," and "distinguishing features up close" in the preservation and restoration of cultural relics. The imitation wood grain paste is composed of tung oil, lime, talcum powder, and sawdust mixed in a mass ratio of 1:2:1:2.

[0035] Step 3: Apply wood rot adhesive to both sides of the wood chips and fix them with rope or tape. The initial setting time is 24 hours and the final setting time is 72 hours. The wood rot adhesive is made by mixing tung oil, lime, wood chips and hemp fibers in a mass ratio of 1:3:2:2.

[0036] Step 4: After completely dissolving 3g of fluororubber 2311 in 97g of ethyl acetate, apply it to the surface of the ancient ship with a paint brush.

[0037] Example 3

[0038] Step 1: First, use drills of different diameters to forcefully rotate the infusion hole to a depth of 3-4 cm at the rotten wood reinforcement part of the ancient ship from the Southern Song Dynasty. Then, insert an L-shaped stainless steel needle into the infusion hole to inject the rotten wood deacidification and reinforcement agent. The rotten wood deacidification and reinforcement agent is composed of 25 mL of micro-nano lime and 75 mL of ethanol solution of ethyl cellulose with a mass concentration of 1%.

[0039] Step 2: Apply the imitation wood grain paste to the repaired area of ​​the ancient ship using a caulking tool and smooth it out. Then, use the imitation wood grain tool to pull and scrape back and forth to create the wood grain effect, achieving the desired texture, depth, and height of decayed wood. This achieves the goal of "restoring the old as it was," "looking the same from a distance," and "distinguishing features up close" in the preservation and restoration of cultural relics. The imitation wood grain paste is composed of tung oil, lime, talcum powder, and sawdust mixed in a mass ratio of 1:2.5:2:3.

[0040] Step 3: Apply wood rot adhesive to both sides of the wood chips and fix them with rope or tape. The initial setting time is 24 hours and the final setting time is 72 hours. The wood rot adhesive is a mixture of tung oil, lime, wood chips and hemp fibers in a mass ratio of 1:2.5:3:1.5.

[0041] Step 4: After completely dissolving 6g of fluororubber 2311 in 94g of propanol, apply it to the surface of the ancient ship with a paint brush.

Claims

1. A method for the protection and restoration of decayed wood from ancient ships, characterized in that: Includes the following steps: Step 1: First, use drills of different diameters to forcefully rotate the infusion hole to a depth of 2-4cm at the reinforcement part of the wooden boat. Then, insert an L-shaped stainless steel needle into the infusion hole to inject the decayed wood deacidification and reinforcement agent. The decayed wood deacidification and reinforcement agent is made by mixing micro-nano lime and 2% ethyl cellulose ethanol solution in a volume ratio of 1:

2. Step 2: Apply the imitation wood grain paste to the patched area of ​​the ancient ship using a caulking tool and smooth it out. Then, use the imitation wood grain tool to pull and scrape back and forth to create the wood grain. The imitation wood grain paste is made by mixing tung oil, lime, talcum powder and wood chips in a mass ratio of 1:3:0.5:

1. Step 3: Apply wood rot adhesive to both sides of the wood chips and fix them with rope or tape. Initial setting takes 24 hours and final setting takes 72 hours. The wood rot adhesive is a mixture of tung oil, lime, sawdust, and hemp fibers in a mass ratio of 1:2:1:

1. Step 4: After completely dissolving the fluororubber in the organic solvent, apply it to the surface of the ancient ship with a paintbrush; the mass concentration of fluororubber in the organic solvent is 3% to 6%; the fluororubber is fluororubber F2311, which is a copolymer of vinylidene fluoride and trifluorochloroethylene; the organic solvent is any one of acetone, propanol, ethyl acetate, and butyl acetate.

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