On 17 February 1938, Barrow wrote to William Ferguson, a local lawyer, asking how to patent the roller-type laminator and his restoration process. His description of the history of the laminator's invention, its timing, and his contribution to the process did not match the documented evidence cited in Chapter 8 even at this early date.
On October 9, 1936, I thought of a method for applying sheets of cellulose acetate to both sides of paper. This process consists of placing cellulose acetate, (sheeting), on each side of the paper to be laminated, preheating this thermo plastic material to a soft and plastic stage and placing it between two rolls under pressure which forces the soft cellulose acetate film into the pores of the paper giving a stronger and more durable sheet. the temperature and pressure depends on the density of the paper to be treated, the more dense requires a higher temperature and greater pressure.
I do not claim to be the first to impregnate paper with cellulose acetate film as it has been done before with steam heated hydraulic press, but believe that I am the first to use rolls in this process, (October 14, 1936) . . .
I have also discovered that by using tissue . . . sandwiched between two sheets of cellulose acetate and applying this mixture to both sides of the substance to be laminated will give greater strength to the material so treated....(Barrow 1 February 1938)
Barrow sought the legal services of Washington-based patent attorneys, Cameron, Kerkam, and Sutton, recommended by Ferguson, to press his patent application. The law firm's initial response from Loyd H. Sutton was not promising.
The additional search has developed prior art which leads me to gravely doubt the wisdom of seeking patent protection on this invention....you are aware that it was old prior to your present invention to preserve documents by coating and/or penetrating the same with cellulose acetate or equivalent acting preserving materials....No patent has been found, however, which expressly discloses the idea of using rollers for effecting this pressure, but rollers are a well known way of exerting pressure and from my past experience with the Patent Office I feel quite confident the Patent Office would see nothing patentable in using rollers rather than some other form of pressure....Moreover, . . . rollers are commonly used in applying pressure when impregnating fabrics. . . .
Therefore, I see little hope of securing worth while patent protection on your procedure. It may be possible to obtain quite specific claims on particular details of procedure not disclosed in the foregoing patents, but considering the rather narrow field in which the invention would be used and the difficulty of preventing people from using the procedure if they saw fit to disregard your patent, I gravely question the wisdom of going to the expense of taking out a patent with such little prospect of financial return therefrom. (Sutton 26 March 1938, 1)
Sutton, in the same letter, continued to instruct Barrow of the limited protection his patent would offer him even if his application succeeded.
With respect to the apparatus which you use, I understand that it is little more than a press with a pair of calender rolls attached thereto. As a piece of apparatus, the question of invention must be determined . . . there is a relatively large body of prior . . . apparatus for applying heat and pressure, . . as a piece of apparatus would be almost certainly restricted to such narrow details of structure that the patent would afford you little protection, . . . [a patent] would not prevent others from designing other pieces of apparatus employing heated pressing plates associated with calender rolls ....(Sutton 26 March 1938, 1-2)
Sutton offered the services of his law firm if Barrow would do a careful analysis of all the patents that appear to have prior claim to the process.
I cannot hold out to you much hope of securing a patent that would be of any very considerable value in so far as obtaining a monopoly that would result in financial return. If, in spite of the foregoing, you feel that the securing of a patent would be of sufficient value to you to warrant the expenditure, we shall be glad to exert our best effort to secure such patent protection as possible, and in this event we would like to have the benefit of a careful analysis by you of the cited art to show precisely wherein the patents first referred to will not accomplish what you have in mind.... (Sutton 26 March 1938, 2)
Like Emery before him, Barrow evidently thought having a lamination patent was worth the effort and expense. He began a long-lasting correspondence resulting in several attempts to patent various combinations of his process and laminator. He wrote Sutton and listed what he felt was unique about his process and laminator. First, he changed the emphasis of his claim from lamination only to the use of lamination to facilitate other kinds of restoration processes.
In my process I find some differences and would like for you to study the following and determine whether I have made sufficient discoveries to justify a patent. I find the following are not incorporated in previous patents:
1. Pre-heating the material.
2. The use of rolls when not applying an adhesive.
3. Cooling the material while not under pressure.
a. This is accomplished by using tracing cloth, or similar flexible material between the plates, this forming a double form, where other patents only mentioned one or speak of it as a form.
b. The economy is obtained by speeding the operation of applying this material and not requiring any artificial means of cooling.
4. Removal of ink.
5. Splitting of the paper and re-inforcing the center with new materials.
6. Splitting the sheet and removing the fibers while the ink remains on the thermoplastic material and transferring the ink in its original position to new paper or any other material desired. (Barrow 2 April 1938, 1)
Barrow applied the laminator to the infrequently used restoration technique of paper splitting (see Chapter 5) and further developed it using lamination so that almost all of the original paper could be removed leaving nothing of the original but the printing or writing ink. The writing or printing ink was then laminated to a new sheet of paper.
After the document has been impregnated with one sheet of tissue sandwiched between two sheets of cellulose acetate, the overlapping margins of this material are trimmed close to the edge of the document. By pulling apart the layers of film on each side of the paper it will split through the center. the fibers may be removed by scraping and soaking in water, which will enable one to remove them with greater ease. The films that hold the ink may again be split apart due to the fact that the tissue will split in the same manner as that of the old paper. The film of acetate containing the old ink and a few of the fibers of the tissue may be heated and pressed into new paper. (Barrow 2 April 1938, 1-2)
Barrow also discussed his plans for sales of his laminator in the same letter to Sutton. He felt that the field was so small and esoteric that he would not have any significant competition.
I appreciate the fact that there will only be a few libraries in this country that will be able to afford such a machine as I possess. I have had in mind having similar machines built on order and sell them to such institutions that could afford them. Provided I am not infringing on any one else's patent in doing this, I do not have a great deal of fear of any library infringing on my own, as I do not think there would be any librarian who would take a chance on a suit when they could be able to obtain the use of my process for only a small additional cost, by purchasing the press from another source. in view of the fact that this field is extremely limited, I am not contemplating competition from [others who may be] . . . manufacturing presses, as they would not know how to use them after one was built. (Barrow 2 April 1938, 2)
Barrow was intrigued by the process of transferring the ink or writing from one document to another using lamination. He consistently promoted "ink transfer", as he called the process, although to little effect. Ink transfer was one of several other lamination applications that did not succeed with his library and archives customers in spite of his promotional efforts.
On 18 April 1938, Barrow again wrote answering Sutton's original questions on how his process differed from other patents. This time Barrow took the prior patents obtained from Sutton to Scribner who examined them, and answered Sutton's complex questions in detail.
He [Scribner] was very much interested in the copies [of the patents] that you had turned over to me, due to the fact that the application of cellulose acetate film to paper originated in his laboratory. He stated that Vinyl Resin [sic] would belong to an entirely different group from cellulose acetate and cellulose derivatives. He stated that this would not in any way affect a patent of the type desired. This is patent granted, Sloan, No. 2, 013, 865, September 10, 1935. His comment on patent granted, Walsh et al., No. 2, 079,641, May 11, 1937, was that it would not affect my process, nor the method used at the National Archives because a cement or adhesive was required to make the film adhere to paper. (Barrow 18 April 1938, 1)
Barrow used Scribner's opinions to help bolster his case for originality. "[Scribner] could not see why I should not be granted a patent on the method of application that I use. I told him you stated that rolls were nothing new, neither was the application of heating and pressure to thermo-plastic materials in impregnating porous materials. He stated this was very true, but adding together a combination of ideas that had not been assembled in this order before was new and novel in the paper industry, and felt that I was deserving of a patent on this method of application" (Barrow 18 April 1938, 1).
In the same letter, Barrow continued to discuss a disagreement between him and Sutton. He again brought Scribner into the discussion as the expert.
Since the patents you sent me apparently do not affect the thermo-plastic films of cellulose and cellulose derivatives and their impregnation into paper without adhesives, do you not think it possible to obtain a patent on preheating, the use of rolls as a means of pressure, and the use of a double form....Whereas, the rolls to obtain pressure is nothing new, it is a necessary medium of pressure when preheating and double form are thus involved. If you do not agree with me I would like to suggest you call Mr. B. W. Scribner and get his view point in this matter. I feel he is one of the best informed men on paper in this country. Please do not feel that I have not the greatest regard for your ability in obtaining patents by making the above suggestion, but upon my recent visit to your office you stated we could only hope to approach each other's point of view as near as possible.
Would it be of any value for me to come to Washington at the time the patent board passes their judgement on my process? If so, I will be glad to be there at any time that you suggest, and I may also be able to get Mr. Scribner to appear with me as his opinion would no doubt carry some weight with the examiners should any question arise. (Barrow 18 April 1938, 2)
By 18 June 1938 Sutton had submitted an application for a patent of Barrow's restoration procedure and laminator. Sutton assured him that, "there seems to be no sound reason why you should not start out to exploit your invention in any way that seems desirable" (Sutton 18 June 1938).
Both NBS and GPO tested various restoration techniques including, but not limited to, lamination with tissue, silk, and cellulose acetate foil (Barrow 24 April 1938). Barrow supplied restored samples and information on current restoration techniques to the chemists who had apparently requested them: "I am enclosing sample of gelatine [sic] and the manufacturers [sic] name that I suggested you might find of value in patching parchment. This should be soaked in water for a couple of hours before heating and applied to the document while warm. After application document should be held under pressure with wax paper on each side until dry" (Barrow 25 April 1938). He also sent samples of restorations using silk and cellulose acetate to Scribner at NBS for use in a joint NBS-GPO study (Barrow 24 April 1938). Augustus E. Giegengack, Public Printer, acknowledged receipt of Barrow's samples on 27 April 1938. He assured Barrow that the laboratory at GPO would keep Barrow informed of the results of their research. Giegengack asked Barrow for "specimens of your process illustrating the points of difference from other known methods . . . in order that we may keep them in our files as an exhibit for permanent reference" (Giegengack 27 April 1938). Barrow answered this letter stressing his primary interest in product testing. "Mr. B. W. Scribner . . . has made quite an extensive study of the permanency of materials used in this process, but has not made tests of the restored documents compared with the silk . . . process. Detailed information along this line would be of a great deal of interest and value to all of us that [sic] are engaged in the restoration of rare manuscripts and documents" (Barrow 2 May 1938).
The first evidence of any paper research actually done by Barrow appeared in the spring of 1938. "I will send you in about two weeks tests that I have conducted on the effects of sulpher dioxide and sunshine on paper restored with [silk] crepeline and cellulose acetate" (Barrow 24 April 1938, 2). He was also planning further research into the factors contributing to paper deterioration, this time working closely with a local medical researcher examining the deteriorative effects on paper caused by handling. "I am planning to make tests on the two different types of restoration relative to perspiration and other secretions that are transferred from the fingers to the document. Also, saliva and particles of food that are also transferred by careless workers." Dr. W. R. Payne of this city is helping me to outline this program, and he states that one will find acidic properties [emphasis mine] in perspiration, as well as an excellent medium for bacterial growth. Any suggestions along this line that may occur to you at any time will be greatly appreciated" (Barrow 24 April 1938, 2-3). Barrow's early research was closely guided by a variety of experts, and it was strictly product development and product testing. His casual reference to "acidic properties" is evidence that he not only knew about the existing chemical research on acid hydrolysis as a primary cause of paper deterioration, but that it was not, at this time, one of his major interests.
Barrow, at this time, was concerned also with research on the strength and flexibility of cellulose acetate. He next asked Scribner's help in studying its aging characteristics: "What could be done with the document should the acetate film fail to hold up in time, and should yellow and crack? How could I cause this condition artificially on paper that has been restored in this manner? I think further restoration could be perfected, but so far under my light test and sulpher dioxide test the samples submitted have improved in folding endurance. This may be a big order, nevertheless, any suggestions will be appreciated" (Barrow 24 April 1938, 2-3). Barrow apparently did not know about or use the newer accelerated aging techniques for paper from the Swedish Model using wet or dry oven aging that were already standard in paper chemistry. He used only the older techniques using exposure to sunlight (high in ultraviolet light) that required no specialized equipment.
Barrow reported some of the results of his aging and handling study in a 2 May 1938 letter to Morris J. Kantrowitz.
Since seeing you [Kantrowitz] I have subjected to sunlight a number of specimens restored with acetate and [Japanese paper] . . . find their folding resistance stands up very well, whereas untreated specimens, and those restored with silk, showed a decrease of from twenty to forty per cent. Similar results were found when subjected to sulpher dioxide. a local physician is helping me to make plans for the study of the effect of perspiration, saliva, and food particles transmitted from the hands to paper. on a test of saliva whereas untreated specimens and those with crepeline showed a good decrease. the acetate film no doubt has a possible chance to resist the impurities that are transferred from the fingers to paper when handling. (Barrow [to Kantrowitz] 2 May 1938, 1)
In this letter, Barrow communicated his plans to visit Washington and the chemists at GPO again the following summer (Barrow [to Kantrowitz] 2 May 1938, 1-2). He also planned to use this visit to meet Sutton and discuss the progress of his patent application (Sutton 18 June 1938, 2).
On 2 May 1938, Barrow wrote to Scribner asking him about the effects of oxygen from the air on paper deterioration. The answers to these questions were both well known by chemists and well documented in the chemical literature by that time.
Since last writing you I have run into a rather peculiar condition in my light test and am anxious to know if sunlight alone will break down cellulose fibers, or does it act as a catalytic agent for the oxygen in the air. So far all treated specimens in the sun have held up very good, with the exception of one that the edges were trimmed, and this showed about a forty per cent break down in the folding indurance [sic]. This has caused me to wonder if the sunlight does not accelerate oxidation and when the samples were sealed little effect was accomplished by the sun as the fibers themselves were not exposed to air to any extent. (Barrow [to Scribner] 2 May 1938)
Scribner answered Barrow on 9 May 1938 "Relative to your inquiry on the effect of light, we do not believe that the oxygen content of paper would be very much different in cut [trimmed] and uncut [untrimmed] samples" (Scribner 9 May 1938). in fact, cellulose acetate foil, like most plastic films, is slowly permeable to gasses, but Barrow continued to describe his lamination process as "sealing" a document from the ill effects of air (Barrow develops process . . . 1939).
Barrow made further improvements in his lamination method during the spring and summer of 1938. He described these developments to Scribner on 11 July 1938. "We are working on an attachment that will bring the form back to the operator when it drops in the chute. This will be a time saver as well as less steps to be made by the operator" (Barrow 11 July 1938). Other changes are also described in this letter to Scribner.
I have found thin cardboard to be more desirable to use than metal plates in the form. They are cheaper, require less time to heat, can be handled with bare hands after applying pressure and do not impart the metallic feel to the document, but give a softer and more flexible product. There is another improvement made that is of some interest which consists of placing a strip of acetate about 25 per cent thinner than the document along the edge of the document. This makes a narrow margin which is very hard to start tearing as well as giving the margin the same thickness as the document. This also locks the acetate through the tissue fibers and gives quite an elastic edge. (Barrow 11 July 1938)
Barrow was working with both NBS and GPO, through regular correspondence and occasional visits, to develop his restoration process. He apparently felt the need to bring them together to discuss test results. He wrote Scribner on 11 July 1938:
After you and Mr. Kantrowitz have made tests on the comparative virtues of the two different processes [silking and cellulose acetate lamination], I would like to come up to Washington and discuss the matter with you and in the meantime I expect to have some information that may be of interest to you. Would it be agreeable with you to have Mr. Kantrowitz and Mr. Spencer to be [sic] present at such a time, provided they would like to join in such a discussion? I feel that such a meeting might be beneficial to all concerned and would like to know how you felt about it. (Barrow 11 July 1938)
Scribner immediately agreed to the proposed meeting (Scribner 15 July 1938). Barrow then wrote Kantrowitz at GPO on 22 July 1938: "Since you, Mr. B. W. Scribner, . . . and I are all interested in this process, may I suggest that when these tests are completed I come to Washington and we get together and have a full discussion of the various properties of this process [cellulose acetate lamination]. Should such a meeting be agreeable with you and Mr. Spencer please let me know" (Barrow 22 July 1938). Barrow may have wished to use the meeting to discuss an aspect of his patent application; in any event, there is no evidence that a joint meeting was ever held. There is no evidence either that Barrow was concerned, in 1938, with anything having to do with neutralizing or alkalizing acid paper.
Scribner wrote Barrow on 26 July 1938, giving him test results that contained bad news about his new modifications: "Apparently there does not seem to be much difference between the results obtained with the crepeline and with the cellulose acetate and tissue. It is possible that in using both acetate and tissue the paper document [sandwich] becomes so thick and heavy that it loses some of its flexibility" (Scribner 26 July 1938).
On 5 August 1938, Barrow wrote Scribner, "When I first looked over the results of crepeline and cellulose acetate I felt quite disappointed" (Barrow 5 August 1938, 1). Then he carefully explained the problems with the NBS test results that he observed.
It appears to me that either the typist or the one making the fold test unintentionally reversed the collum [sic] of figures for the untreated specimens and those restored with cellulose acetate and tissue. on this particular type of paper out of about 12 different tests, I have not found a single case in which the untreated paper had a greater fold than that restored with cellulose acetate and tissue. in most instances it increased around eight times. Also this same paper has been used in most of my light tests . . . and in no case has the laminated sheet broken down as much as the untreated paper. (Barrow 5 August 1938, 2)
Barrow even mentions that earlier published findings of NBS studies contradict this study's findings. He interacts with Scribner in this letter more like a peer than in any prior correspondence, yet he is careful to soothe any hurt that his assertions may have caused Scribner. "Please do not think I am being critical of your report but it being inconsistent with other tests already made causes me to wonder if a mistake of some type did not occur" (Barrow 5 August 1938, 3). There is no other correspondence on this particular set of data. The importance of this letter rests more upon the change in the tone Barrow used than upon test findings. After this exchange Barrow became more a colleague, a practitioner with an area of expertise of his own, and less Scribner's student.
In January 1939, Barrow wrote Scribner that he had collected samples of old paper. He offered these samples to Scribner to use when NBS investigated the chemical characteristics of old paper. in the same letter, Barrow mentioned his intention to visit NBS again, "I am anxious to accept your invitation to study some of your methods of testing paper and am in hopes that my work will permit me to do this the latter part of the spring or early summer." in the postscript, Barrow asked Scribner to send him "information relative to the detection of groundwood fiber by placing a drop of some type of solution on the paper" (Barrow 18 January 1939). This letter indicates that as late as January 1939, Barrow had concentrated on product development. He had mentioned no interest in research on paper characteristics not directly related to the development of his lamination product before 1939. He also had little knowledge of how to do that chemical research even if he had wanted to do it. There is no doubt though that Barrow was interested in learning more about testing paper characteristics, which involved learning some general techniques in chemical research. Scribner immediately answered Barrow's letter, welcomed his interest in learning test methods, accepted his samples of old paper to be used in NBS's research, and agreed to send information on the spot test for detecting groundwood in paper (Scribner 23 January 1939).
Barrow, in a 6 February 1939 letter to Scribner, revealed that he was thinking about the need for general paper permanence information. "The fiber analysis of the early Arabic manuscripts contained in your recent bulletin was most interesting. We are in need of more data of this nature to use as a yard stick in judging the permanency of paper" (Barrow 6 February 1939). at the end of February, Barrow visited Scribner to learn some standard paper testing methods (Barrow 13 February 1939).
In March, Briggs wrote Barrow requesting his participation in an upcoming NBS research project devoted to testing the characteristics of various plastics and processes then being used in lamination. Briggs asked Barrow to contribute samples of his lamination method to be tested and comment on the planned research agenda. "It seems to be desirable to obtain additional test data relative to the lamination of documents with cellulose sheetings. As a part of our work on the preservation or records, we propose to do this and are enclosing a tentative research program. We would like very much to have your opinion of this and any suggestions you may wish to make as to changes you may consider desirable" (Briggs 24 March 1939). Barrow suggested one addition to the research plan: "measure the thickness of the laminated papers before and after subjecting them to high and low humidity. Should there be a decided swelling of the papers, it would likely effect a bound volume thus laminated" (Barrow [to Briggs] 31 March 1939). This suggestion was based upon binding or craft considerations important to a practitioner, not a consideration important in chemical research or with measuring physical characteristics of paper per se. Barrow apparently continued to serve the research team in the role of practitioner, one who supplied samples and applied findings. Scribner wrote to express his thanks for Barrow's participation in the research program and added that: "The additional test which you suggest appears to be very desirable and we shall include it in our research program" (Scribner 14 April 1939).
Barrow wrote Scribner on 31 March 1939 asking for information on file folders.
I would like to know the name of a manufacturer who makes the type of paper suitable for filing folders as mentioned in one of your recent Bulletins. This type has a low content of acid as well as very little degraded cellulose and holds up well under accelerated aging. The Virginia State Library and other similar institutions who store old documents have at different times requested such information. I would also like to know the correct name of this paper in order that I might receive the correct type when ordering. (Barrow [to Scribner] 31 March 1939)
This request demonstrates that Barrow had, by 1939, learned from NBS and its publications which characteristics of paper and its testing were important for permanence, for example, acidity, degraded cellulose, and accelerated aging. in answer to his question C. G. Weber, Acting Chief of the Paper Section of NBS (during one of Scribner's brief absences) sent Barrow a copy of the "Proposed Revision of Federal Specification for File Folders" (Weber 6 April 1939).
Chapter 10 details the development of Barrow's knowledge of acid hydrolysis, the neutralization of acid through aqueous alkalization, and his incorporation of alkalization into his restoration process.