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Home Cosmetic Science Talk Formulating Preservative needed for cleaning product with pH 10?


  • Preservative needed for cleaning product with pH 10?

    Posted by StaffordshireDog on August 31, 2021 at 10:11 pm

    I am making a cleaning product that’s basically soap and water. PH comes in at about 10. 800 ml water, 8 ml soap concentrate more or less. Preservative needed? I’ve seen mixed answers to this. Thoughts are welcome. Thank you. 

    PhilGeis replied 1 year, 8 months ago 2 Members · 5 Replies
  • 5 Replies
  • PhilGeis

    September 1, 2021 at 12:15 am

    Dilute soap - any heat in prep?  If water is in control and small batches, prob not with effective cleaning and sanitization.
    If preservative needed - try benzoisothiazolinone (e.g. Proxel) or Gylcoserve (DMDM Hydantoin).

  • StaffordshireDog

    September 8, 2021 at 10:55 pm

    Hi Phil. Yes, it’s diluted soap no heat in prep. What about phenoxyenthanol?I was thinking no preservative, but then my use by dates would be unknown. I guess I can use the manufacturer guidelines to establish safe minimums that way. Thanks.

  • PhilGeis

    September 9, 2021 at 1:00 pm

    Use by date - on what would you base that and can you say more about “manufacturer guidelines.”

    In what country will you sell?

  • StaffordshireDog

    September 13, 2021 at 3:29 am

    USA. We have laws that vary by state and New York and California have strict laws for labeling. 

    The actual safe use by date for my product could be 2 years. However, the manufacturer of the preservative might have a window of 12 months to 24 months based on the percentage of solution that is preservative. The product could be safe for use for up to 24 months in this case, but the minimum time of 12 months is what I could use for the use by. 

  • PhilGeis

    September 13, 2021 at 10:28 am

    Not aware of a “safe use” or “use by” provision for household products, esp. re. micro contamination.  Can you share the regulation?  
    Household product preservation targets manufacturing contamination, not in-use contamination by consumers that is a concern for cosmetics.
    Whether appropriate and required for household product or not, use by, ex dates or the moronic PAO should not be used to excuse unstable products.    Why do you think no consumers will not be using your product one year after manufacture?